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39423 DRAINAGE/ENGINEERS - a ~ Drainage Report, R.A. Bonucce----i Marietta at SSpokane County, Was--'Iington .J~. J L ~ ri ~T sPwj~ EC) U:..1:Y O; FiCE k PnniLtiT V(f ~ Stateme FiET'tJHIN 10 CJi.lNt'Y EstiG1NEER The following report was prepared under my direction. The contents are engineeri.ng opinions derived using procedures that meet industry and professional standards. This document was not prepared as a construction document. Alan E. Gav Professional Engineer Printed Nanae Title Civil EnLyineer June 28, 2000 . • Title Date , - ~ E.~~ F wASy ~ ~~s RECE)VED JllN M 2960 r JP"' ~'G ~ 29 194 ; SPOKANE COUNTY ENGINEER O CIS'TF?/ ql.. ~ ' ExPIRES .13 5 ' - TECHCON, INC. Professional Engineers • Certified Emironmental Specialists • Project tiianagers • Steel Detailers DRAINAGE REPORT ROBERT A. BONUCCELLI MARIETTA AT SULLI VAN INDUSTRIAL DEVELOPMENT SPOKANE COUNTY, WASHINGTON Proposed improvements to the site at the extension of Marietta Road west of Sullivan Road, triggcr the need foi- stonn water runoff disposal irnprovements by Spokane County regulation. The calculation sheets following this narrative include details of the analysis showing that the proposed drainage improvements are adequate to control runoff on the site for a 10-year event, and safely discharge runoff for larger events at a rate equivalent to or less than the discharge rate in the pre-developed condition for the site. Key assuinptions made for the site include assuming that the soils are Garrison gravely loam and Garrison very stony loam with an effective permeability equal to or greater than 0.36 inch per hour (0.36"/hr.). Another key assumption is that the intensity-duration-frequency (IDF) curves for t11e site conform to the IDF curves for Spokane as published in Chart 34 of the Washington State Department of Transportation (WSDOT) Hydraulics Manual. Tlle drainage areas in the development are designated by parcel and roadway. Parcel basins are shown as Parcel 1 through'9, with Parcel 4B being held in reserve for drainage. Roadway basins are designated as Marietta West, Marietta Middle and Marietta East. These drainages are shown with these designations on the drainage and grading plans presented with this report, as well as the times of concentratian for Marietta Wcst, Marietta Middle and Marietta East. The Bowstring method was used to assure that thE roadside swales will have adeguate volume to contain a ten year storm event The existing hydrologic conditions for the site arc undeveloped. The calculated peak runoff for the existing site, using the SCS method, folloNvs: Q=(P - 0.2S)2 / (P + 0.8 S), whcre: Q= runoff in cfs, P= total stonn rainfaU, S= potential abstraction in inches S= 1000/CN -10 CN = cutve nuinber In this case, the CN = 70, since the soil group is Garrison, an "B" hydrologic soil. Thc land use is approximately the same as pasture in fair condition, thus the 70 rating. S= 4.29 P= 3.04 inches in 24 hours for a 100 year storm. Q= 0.737 inches over tlle site. The site drainage basin is approximately the 19.3 acres of the site, since the drainage is bounded .1 on the west by the old Cominco property, which slopcs to the west, the north edge of the site is the rohnson Mathey property with its own hydrologic controls, the south edge of the site is the old Milwaukee Railroad right-of-way, and drains toward the south, and the east edge is Sullivan Road. Therefore the total pre-developed runoff from a 100 year event is predicted to be 620,000 cubic feet. For the peak runoff, the hydraulic length is 1234 feet, which equates to an equivalent area of 19.3 acres. Using the Type II storm curve, the estimated peak runoff for a CN70 is 11 cfs/in of ninoff. This equates to 8.1 cfs allowable peak runoff. For a 10 year storm, P= 2.12, and Q= 0.287 inches over the site; therefore the allowable peak runoff is 3.16 cfs for a 10 year storm. The predicted peak amount is 0 cfs for the SW and SE basins, unless a runoff-over- ice condition develops that fills over 7000 cubic feet of storage, in which case up to 3 cfs would be discharged through the overflow pipe in the southwest corner of the SW swale. 6onuccelli Development Marietta & Sullivan 28-Jun-00 Stormwater Disposal Entire Site is One Parcel Drain to Indivitlual Parcel 208 swales Areas Required: Resulting Landscaping Area: TOTAL TOTAL NET NET MAX, UNBUILD- MIN LOADING REQ. Sublot # Type III Type IV AREA ACRES AREA ACRES BUILDING ABLE PARKING DOCK AVAIL? SWALE Imp.Area acres 1 2892.5 0 83135 1.908517 80242.5 1.842114 32422.65 44094.76 1800 OK 6158.994 73907.93 1,696693 2 3499 0 229719 5.273623 226220 5.193297 137831,4 0 56235.15 3600 OK 16003.59 192043 4.408702 3 993.6 0 106456 2.443893 105462.4 2,421084 63873.6 26060.4 2700 OK 7502.33 90027.96 2.066758 4 203.1 0 78459 1.801171 78255.9 1.796508 47075.4 19206.74 1800 OK 5513.456 66161.47 1.518858 5 993.6 0 93875 2.155073 92881.4 2.132264 56325 22980.58 1800 OK 6567.293 78807.52 1.809172 6 950 950 94052 2.159137 92152 2.115519 56431.2 23023.91 1800 OK 6579.393 78952.72 1.812505 7 1003.05 1250 50000 1.147842 47746.95 1,096119 20000 27199.97 360 OK 3736.665 44839.98 1.029384 8 700 0 35000 0.803489 34300 0.78742 14000 19039.98 360 OK 2624.665 31495.98 0.723048 9 1973.55 0 38135 0.875459 36161.45 0.830153 14872.65 20226.78 360 OK 2786.396 33436.76 0.767602 ROADUVAY 0 0 37708 0.865657 37708 0.865657 0 0 0 NA 3142.333 37708 0.865657 SWSwale: 3255 0 74739 1.715771 71484 1.641047 0 0 o a TOTAL: 921278 21.14963 TOTAL: 60615.11 SQ. FT. 15.17952 Bonuccelli Development Marietta & Sullivan 28-Jun-00 Stormwater Disposal Bowstring Method Calculation, Roadside Swale Capacity, Marietta Area 1: West End, Marietta Swale Area: 1600.588 square feet Volume: 1997.27 625.5295 1997.52 1113.059 217.3236 cu.ft. 1997.77 1600.588 556.5295 cu.ft. Pond Infiltration Rate: 0.005213 cfs Drywell Infiltration Rate: 0.3 cfs (Garrison Gravelly loam) No. of Drywells: 2 Drywell Volume: 108.9 cubic feet Total Available Storage Volulme: 665.4295 cubic feet Use Bowstring Method to check adequacy of Swale: Time increment; 5 min. Time of Concentration: 5.5 min. Storage req.: Outflow (c.f.s.) 0.61 cfs 208.6178 cf. Design year flow 10 year Area (acres) 0.36 Developed C factor: 0.848902 Area x C 0.31 No.1 No.2 No.3 No.4 No.S No.6 No.7 Time Inc. t Intensity Q dev. V in V out Storage No. 1 x 60 (in./hr) A*C*No.3 Out * No.2 5 300 3.18 0.970601 390.1816 181.5638 208.6178 10 600 2.24 0.683694 411.4948 363.1276 48.36711 15 900 1.77 0.54024 487.2264 544.6915 -57.46508 20 1200 1.45 0.44257 531.9111 726.2553 -194.3441 25 1500 1.21 0.369317 554.6657 907.8191 -353.1534 30 1800 1.04 0.317429 571.9662 1089.383 -517.4167 35 2100 0.91 0.277751 583.7956 1270.947 -687.1511 This is the worst-case area; no further analysis is necessary. Bonuccelli Development Industrial Development at Sullivan and Marielta 28-Jun-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Use conservative 5 min. intensity i= 3.2 in/hr Disposal Capacity: Garrison Gravelly LoamNery Stony Loam Soil Estimated TurF Infiltration Capacity q= 0.36 in/hr Ratio of i/q 8.888889 Maximum Storage Depth: 6 in. 10 year, one hour intensity: 3.2 in/hr 10 year, 24 hour total: 2.12 in. Parcel 1 Drain Basin Total Improved Impervious Surface Area: 73907.93 square feet . Asphalt Impervious Surface Area: new: 39281 square feet Roo(: direct: 32422.65 square feet Sidewalk: new: 2204.738 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overilow. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 9227.066 square feet Depressed Infiltration Area: 6158.994 square feet cultivated surface Additional available infiltration volume on side slopes: Perimeter 6" above bottom 470.8756 square feet additional on slopes Total Available for Infiltration: 6629.87 square fee = 3197216 ft3 Total Required Under County Standard: 1636.689 ft3 OK Hydrology Check: • Rational Method: Peak Runoifi, 10-year storm, Q=CIA Impervious Surface C- 09 Pervious Surface C: 0.25 10-year intensity. 3.2 in/hour Time of concentration: 3.65 min. Area Impervious: 73907.93 square feet Area Pervious• 9227.066 square feet Peak Q: 5.06 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale: 2597.196 square feet Peak Q. perv, non-swale: 0.05 cfs Infiltration capacity, perv, non swale. 0.02 cfs Engcalc 1-G-1 Bonuccelli Development Industrial Development at Sullivan and Marielta 28-Jun-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Peak Q, remainder: 5.03 cfs Swale Infiltration Capacity: 0.0552 cfs drywell infiltration cap : 0.3 cfs each (1 total) Storage Required, 5 minute Storm: 1403.71 cubic feet Storage Available, Swale Only: 3197.216 cubic feet Plus Drywells: 54.45 cubic feet Total: 3251.67 cubic feet OK Peak Runoff, 50-year storm: (5 minute) 50-year intensity: 5.1 in/hour Peak Q: 8.06 cfs Storage Required: 2394.30 cubic feet Swale Plus Drywell: 3251.67 cubic feet OK Parcel 2 Drain Basin Total Improved Impervious Surface Area: 192043 square feet Asphalt Imperoious Surface Area: new: 51400 square feel Roof: direct: 137831.4 square feet Sidewalk: new: 2811.758 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include slorage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 37675.96 square feet Depressed Infiltration Area: 16003.59 square feet cultivated surface Additional available infiltration volume on side slopes: Perimeter 6" above bottom 759.0317 square feet additional on slopes Total Available for Infiltration. 16762.62 square fee = 8191.551 f13 Total Required Under County Standard: 2141.662 ft3 OK Hydrology Check: Rational Method, Peak Runoff, 10-year storm, Q=CIA Imperoious Surface C: 0.9 Pervious Surface C: 0.25 10-year intensity: 1.95 in/hour Time of concentralion: 13 min. Area Imperwous: 192043 square feet Area Pervious: 37675.96 square feet Peak Q. 8.16 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale: 20913.34 square feet Engcalc1-G-2 i • Bonuccelli Development Industrial Development at Sullivan and Manetta 28-Jun-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Peak Q, perv, non-swale: 0.23 cfs Infiltration capacity, perv, non swale. 0.17 cfs Peak Q, remainder: 7.98 cfs Swale Infiltration Capacity: 0.1397 cfs drywell infiltration cap.. 0.3 cfs each (1 total) Storage Required, 13 minute Storm: 5865.06 cubic feet Storage Available, Swale Only: 8191.551 cubic feet Plus Drywells: 54.45 cubic feet Total: 8246.006 cubic feet OK Peak Runoff, 50-year storm. (13 minute) 50-year intensity: 2.7 inlhour Peak Q: 11.30 cfs Storage Required: 8751.66 cubic feet Swale Plus Drywell: 8246.006 cubic feet NG Storage Available, 12": 16762.62 cubic feet OK Parcel 3 Drain Basin Total Improved Impervious Surface Area: 90027.96 square feet Asphalt Impervious Surface Area: new: 24851 square feet Roof. direct: 63873.6 square feet . Sidewalk: new: 1303.02 square feet Ulilize biofittration swale (grassy) for disposal. Assume antecedant safurated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 16428.04 square feet Depressed Infiltration Area: 7502.33 square feet cultivated surface Additional available infiltration volume on side slopes: Perimeter 6" above bottom 519.696 square feet additional on slopes Total Available for Infiltration: 8022.026 square fee = 3881.089 ft3 Total Required Under County Standard: 1035.473 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year intensity: 3.2 in/hour Time of concentration: 4.6 min. Area Impervious: 90027.96 square feet Area Pervious: 16428.04 square feet • Engcalcl-G-3 Bonuccelli Development Industrial Development at Sullivan and Manetta 28-Jun-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Peak Q: 6.25 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale: 8406.011 square feet Peak Q, perv, non-swale: 0.15 cfs Infiltration capacity, perv, non swale: 0.07 Cfs Peak Q. remainder: 6.18 cfs Swale Infiltration Capacity: 0.0669 cfs drywell infiltration cap.: 0.3 cfs each (1 total) Storage Required, 5 minute Storm: 1745.12 cubic feet Storage Available, Swale Only: 3881.089 cubic feet Plus Drywells: 54.45 cubic (eet Total: 3935.543 cubic feet OK Peak Runoff, 50-year storm: (5 minute) 50-year intensity: 51 in/hour Peak Q: 9.97 cfs Storage Required• 2967.11 cubic feet Swate Plus Drywell: 3935.543 cubic feet OK Parcel 4 Drain Basin Total Improved Impervious Surface Area: 66161.47 square feet Asphalt Impervious Surface Area: new: 18126 square feet Roof: direct: 47075.4 square feet Sidewalk: new: 960.3372 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 12297.53 square feet Depressed Infiltration Area. 5513.456 square feet cultivated surface Additional available infiltration volume on side slopes- Perimeter 6" above bottom 445.5159 square feet additional on slopes Total Available for Infiltration: 5958 972 square fee = 2868.107 ft3 Total Required Under County Standard: 755.2388 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA tmpervious Surface C: 0.9 Pervious Surface C: 0.25 Engcalc1-G-4 Bonuccelli Development Industrial Development at Suilivan and Marietta 28-Jun-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). 10-year infensity: 2.5 in/hour Time of concentration: 8 min. Area Imperoious: 66161.47 square feet Area Pervious: 12297.53 square feet Peak Q: 3.59 cfs Peak Infillration Rate: 0.36 in/hour Pervious Surface, non-swale: 6338.559 square feet Peak Q, perv, non-swale: 0.09 cfs Infiltration capacity, perv, non swale: 0.05 cfs Peak Q, remainder: 3.54 cfs Swale Infiltration Capacity: 0.0497 cfs drywell infiltration cap.: 0.3 cfs each (1 total) Storage Required, 8 minute Storm: 1531.87 cubic feet Storage Available, Swale Only: 2868.107 cubic feet Plus Drywells: 54 45 cubic feet , Total: 2922.561 cubic feet OK Peak Runoff, 50-year storm• (8 minute) 50-year intensity. 3.65 in/hour Peak Q: 5.25 cfs Storage Required: 2481.68 cubic feet Swale Plus Drywell: 2922.561 cubic feet OK Parcel 5 Drain Basin Total Improved Impervious SurFace Area: 78807.52 square feet Asphalt Impervious Surface Area: new: 21333 square feet Roof: direct. 56325 square feet Sidewalk: new: 1149.029 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacily. Available Grassy Area: 15067.48 square feet • Depressed Infiltration Area: 6567.293 square feet cultivated surface Additional available infiltration volume on side slopes: Perimeter 6" above bottom 486.233 square feet additional on slopes Total Available for Infiltration: 7053.526 square fee = 3405 205 ft3 Tolal Required Under County Standard: 888.8954 ft3 OK Hydrology Check: Engcalc1-G-5 Bonuccelli Development Industnal Development at Sullivan and Marietta 28-Jun-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Ralional Method. Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0 25 10-year intensity: 2.6 inlhour Time of concentration: 7.5 min Area Impervious: 78807.52 square feel Area Pervious: 15067.48 square feet Peak Q: 4.46 cfs Peak Infiltration Rate. 0.36 in/hour Pervious Surface, non-swale: 8013.954 square feet Peak Q, perv, non-swale: 0.12 cfs Infiltration capacity, perv, non swale: 0.07 cfs Peak Q, remainder. 4 39 cfs Swale Infiltration Capacity. 0.0588 cfs drywell infiltration cap.: 0.3 cfs each (1 total) Storage Required, 7.5 minute Storm: 1814.73 cubic feet Storage Available, Swale Only: 3405.205 cubic feet Plus Drywells: 54.45 cubic feet Total: 3459.659 cubic feet OK Peak Runoff, 50-year storm: (7.5 minute) 50-year intensity. 3.8 inJhour Peak Q• 6.52 cfs Storage Required: 2897.59 cubic feet Swale Plus Drywell: 3459.659 cubic feet OK Parcel 6 Drain Basin Total Improved Impervious Surface Area: 78952.72 square feet Asphalt Impervious Surface Area: new: 21370 square feet Roof: direct: 56431.2 square feet Sidewalk: new• 1151.195 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include slorage volume of drywells as well as drywelt infiltration capacity. Available Grassy Area: 15099.28 square feet Depressed Infiltration Area: 6579.393 square feet cultivated surface Additional available infiltration volurne on side slopes: Perimeter 6" above bottom 486.6807 square feet additional on slopes Total Available for Infiltration: Engcalcl-G-6 Bonuccelli Development Industrial Development at Sullivan and Marietta 28-Jun-00 TechCon, Inc. Prepared by Alan E. Gay, P E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). 7066.074 square fee = 3411.367 ft3 Total Required Under County Standard: 890 43 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year intensity: 2.6 inlhour , Time of concentration: 7.5 min. Area Impervious: 78952.72 square feet Area Pervious: 15099.28 square feet Peak Q: 4 47 cfs Peak Infiltration Rate: 0.36 inlhour Pervious Surface, non-swale: 8033.21 square feet Peak Q, perv, non-swale: 0.12 cfs Infiltration capacity, perv, non swale: 0.07 cfs Peak Q, remainder: 4.40 cfs Swale Infiltration Capacity: 0.0589 cfs drywell infiltration cap.: 0.3 cfs each (1 total) Storage Required, 7.5 minute Storm: 1818.34 cubic feet Storage Available, Swale Only: 3411.367 cubic feet Plus Drywells- 54.45 cubic feet Total: 3465.821 cubic feet OK Peak Runoff, 50-year storm: (7.5 minute) 50-year inlensity: 3.8 inlhour Peak Q: 6.53 cfs Storage Required: 2903.03 cubic feet Swale Plus Drywell: 3465.821 cubic feet OK Parcel 7 Drain Basin Total Improved Impervious Surface Area: 44839.98 square feet Asphalt Impervious Surface Area: new: 23480 square feet Roof. direct: 20000 square feet Sidewalk: new: 1359.999 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 5160.024 square feet Depressed Infiltration Area: 3736.665 square feet cultivated surface Engcalc1-G-7 Bonuccelli Development Industrial Developrnent at Sullivan and Marietta 28-Jun-00 TechCan, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Additional available infiltration volume on side slopes: Perimeter 6" above bottom 366.7696 square feet additional on slopes Total Available for Infiltration: 4103.434 square fee = 1960.025 ft3 Total Required Under County Standard: 978.3324 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year intensity: 3.2 in/hour Time of concentration: 3 min. ' Area Impervious: 44839.98 square feet Area Peroious: 5160.024 square feet Peak Q: 3.06 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale: 1056.59 square feet Peak Q, perv, non-swale: 0.02 cfs Infiltration capacity, perv, non swale: 0 01 cfs Peak Q, remainder: 3.05 cfs Swale Infiltration Capacity• 0.0342 cfs drywell infiltration cap.: 0.3 cfs each (1 total) Storage Required, 5 minute Storm• 814.92 cubic feet Storage Available, Swale Only 1960.025 cubic feet Plus Drywells: 54.45 cubic feet Total: 2014.479 cubic feet OK Peak Runoff, 50-year storm: (5 minute) 50-year intensity: 5.1 in/hour Peak Q: 4.88 cfs Storage Required: 1439.70 cubic feet Swale Plus Drywell: 2014.479 cubic feet OK Parcel 8 Drain Basin Total Improved Impervious Surface Area: • 31495.98 square feet Asphalt Impervious Surface Area: new: 16544 square feet Roof: direct: 14000 square feet Sidewalk: new: 951.999 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated sod conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Engcalcl-G-8 Bonuccelli Development Industrial Development at Sullivan and Marietta 28-Jun-00 TechCon, Inc. Prepared by Alan E. Gay, P E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Available Grassy Area: 3504.017 square feet Depressed Infiltration Area: 2624.665 square feet cultivated surface Additional available infiltration volume on side slopes: Perirneter 6" above bottom 307.3889 square feet additional on slopes Total Available for Infiltration: 2932 054 square fee = 1389.18 ft3 Total Required Under County Standard: 689.3327 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious SurFace C: 0.9 Pervious Surface C: 0.25 10-year intensity: 3.2 in/hour Time of concentration: 5 min. Area Impervious: 31495.98 square feet Area Pervious: 3504.017 square feet Peak Q: 215 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale: 571.963 square feet Peak Q, perv, non-swale: 0.01 cfs Infiltration capacity, perv, non swale: 0.00 cfs Peak Q, remainder. 2.14 cfs Swale Infiltration Capacity: 0.0244 cfs drywell infiltration cap : 0.3 cfs each (1 total) Storage Required, 5 minute Storm: 545.26 cubic feet Storage Available, Swale Only: 1389.18 cubic feet Plus Drywells: 54.45 cubic feet Total: 1443.634 cubic feet OK Peak Runoff, 50-year storm: (5 minute) 50-year intensily. 5.1 in/hour Peak Q: 3 42 cfs Storage Required: 1003.34 cubic feet Swale Plus Drywell: 1443.634 cubic feet OK Parcel 9 Drain Basin Total Improved Impervious Surface Area: 33436.76 square feet Asphalt Impervious Surface Area: new: 17553 square feet Roof. direct: 14872.65 square feet Sidewalk: Engcalc1-G-9 Bonuccelli Development Industrial Development at Sullivan and Marietta 28-Jun-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). new: 1011.339 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell inflltration capacily. Available Grassy Area: 4698.245 square feet Depressed Infiltration Area* 2786.396 square feet cultivated surface Additional available infiltration volume on side slopes: Perimeter 6" above boltom 316.718 square feet additional on slopes Total Available for Infiltration: 3103.114 square fee = 1472.378 ft3 Total Required Under County Standard- 731.3653 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year intensity: 32 in/hour Time of concentration: 5 min. Area Impervious: 33436.76 square feet Area Pervious: 4698.245 square feet Peak Q: 2.30 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale: 1595.13 square feet Peak Q, perv, non-swale: 0.03 cfs Infiltration capacity, perv, non swale: 0 01 cfs Peak Q, remainder: 2.28 cfs Swale Infiltration Capacity: 0.0259 cfs drywell infiltration cap.: 0.3 cfs each (1 total) Storage Required, 5 minute Storm: 587 35 cubic feet Storage Available, Swale Only: 1472.378 cubic feet Plus Drywells: 54.45 cubic feet Total. 1526.832 cubic feet OK Peak Runoff, 50-year storm• (5 minute) 50-year intensity: 5.1 inlhour Peak Q: 3.66 cfs Storage Required: 1075.18 cubic feet Swale Plus Drywell: 1526.832 cubic feet OK Roadway Basins: West End, North and South Sides: (Mirror Images) Total Improved Impervious Surface Area: 7030.648 square feet Asphalt Impervious Surface Area: Engcalcl-G-10 . . Bonuccelli Development Industrial Development at Sullivan and Marietta 28-Jun-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). new: 5544.86 square feet Roof: new: 0 square feet Sidewalk: new: 1485.785 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: 1 Drywell necessary Available Grassy Area: 800.2942 square feet Depressed Infillration Area- 312.7647 square feet cultivated surface Additional available infiltration volume on side slopes: Assume 3:1 slopes 1.5 feet wide strip around depression Swale: 487.5295 square feet: up to 6" available for storage on 3:1 slopes Total Available for Infiltration: North: 8002942 square fee = 231.8873 ft3 Total Required Under County Standard: 231.0359 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year intensity: 3.2 in/hour Time of concentration: 1 min. Area Impervious• 7030.648 square feet Area Peroious: 800.2942 square feet Peak Q: 0.48 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale: 0 square feet Peak Q, perv, non-swale: 0.00 cfs Infiltration capacity, perv, non swale: 0.00 cfs Peak Q, remainder. 0.48 cfs Swale Infiltration Capacity: 0.0067 cfs Orywell infiltratin cap.: 0.3 cfs Storage Required, 5 minute Storm. 51.86 cubic feet Storage Available, Swale Only: 231.8873 cubic feet Plus Drywell. 54.45 cubic feet Total: 286.3416 cubic feet OK Peak Runoff, 50-year storm. (5 minute) 50-year intensity: 5.1 inlhour Peak Q: 0.76 cfs Storage Required: 137.28 cubic feet OK ' Roadway Basins: Middle, North and South Sides: (Mirror Images) Engcalc1-G-11 Bonuccelli Development Industrial Development at Sullivan and Marietta 28-Jun-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Total Improved Impervious Surface Area: 5200 square feet Asphalt Impervious Surface Area: new: 4000 square feet Roof: new: 0 square feet Sidewalk: new: 1200 square feet Utilize bioflltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: no drywell necessary Available Grassy Area: 456 square feet Depressed Infiltration Area: 228 square feet cultivated surface Additional available infiltration votume on side slopes: Assume 3:1 slopes 1.5 feet wide strip around depression Swale: 228 square feet: up to 6° available for storage on 3:1 slopes 7otal Available for Infiltration: North: 456 square fee = 171 ft3 Total Required Under County Standard: 166.6667 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C. 0.25 • 10-year intensity: 3.2 inlhour Time of concentration: 2 min. Area Impervious: 5200 square feet Area Pervious: 456 square feet Peak Q: 0.35 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale: 0 square feet Peak Q, perv, non-swale: 0.00 cfs Infiltration capacity, perv, non swale: 0.00 cfs Peak Q. remainder: 0.35 cfs Swale Infiltration Capacity: 0.0038 cfs Drywell infiltratin cap.: 0 cfs Storage Required, 5 minute Storm: 104.51 cubic feet Storage Available, Swale Only: 171 cubic feet Plus Drywell: 0.00 cubic feet Total: 171 cubic feet OK Peak Runoff, 50-year storm: (5 minute) 50-year intensity: 5.1 inlhour Peak Q: 0.56 cfs Storage Required: Engcalcl-G-12 Bonuccelli Development Industnal Development at Sullivan and Marietta 28-Jun-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). 167.24 cubic feet OK Roadway Basins: East End, North and South Sides: (Mirror Images) Total Improved Impervious Surface Area: 4314.18 square feet Asphalt Impervious Surface Area: new: 3319 square feet Roof• new: 0 square feet Sidewalk: new: 995.58 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: 1 Drywell Available Grassy Area: 1200 square feet Depressed Infiltration Area: 600 square feet cultivated surface Additional available infiltration volume on side slopes: Assume 3:1 slopes 1.5 feet wide strip around depression Swale: 600 square feet: up to 6" available for storage on 3.1 slopes Total Available for Infiltration: North. 1200 square fee = 450 113 Total Required Under County Standard: 138 275 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Irnpervious Surface C. 0.9 Pervious Surface C: 0.25 10-year intensity: 3.2 in/hour Time of concentration: 1 min. Area Impervious: 4314.18 square feet Area Pervious: 1200 square feet Peak Q: 0.31 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale: 0 square feet Peak Q, perv, non-swale: 0.00 cfs Infillration capacity, perv, non swale: 0.00 cfs Peak Q, remainder: 0.31 cfs Swale Infiltration Capacity: 0.0100 cfs Drywell infiltratin cap.: 0 cfs Storage Required, 5 minute Storm: 91.04 cubic feet Storage Available, Swale Only: 450 cubic feet Plus Drywell: 0.00 cubic feet Total: 450 cubic feet OK Peak Runoff, 50-year storm: (5 minute) Engcalcl-G-13 , . Bonuccelli Oevelopment Industrial Development at Sullivan and Marietta 28-Jun-00 TechCon, Inc. Prepared by Alan E. Gay, P E. Site Hydrology Study Design to 10 year slorm (for review by Spokane County Engineers). 50-year intensity* 5.1 in/hour Peak Q: 0.49 cfs Storage Required• 145.78 cubic feet OK Existing Pre-developed Site Total Improved Impervious Surface Area: . 0 square feet Asphalt Impervious Surface Area: new• 0 square feet Roof: new: 0 square feet Sidewalk: new: 0 square feet Available Grassy Area: 921278 square feet Depressed Infiltration Area: 0 square feet cultivated surface Additional available infiltration volume on side slopes: Assume 3:1 slopes 0 feet wide strip around depression Swale: 0 square feet: up to 6" available for storage on 3:1 slopes Total Available for Infiltration: North: 0 square fee = 0 ft3 Total Required Under County Standard: 0 ft3 OK Hydrology Check: Rational Method: SCS Method . Peak Runoff, 10-year storm, Q=CIA 24 hour storm Impervious Surface C: 0.9 Tc = 25.26 minutes Pervious Surface C: 0.25 Total Area 21.15 acres 10-year intensity: 0.9 inlhour Time of concentration: 36.2 min. Area Impervious: 0 square feet SCS curve No. 61 Area Pervious: 921278 square feet 10-year 24 hour storm. Peak Q: 4.76 cfs 2.12 inches SCS Type II Storm Peak Infiltration Rate: 0.36 in/hour SCS 100 Hydrograph Pervious Surface, non-swale: 921278 square feet simulate capacity of drywell as Peak Q, perv, non-swale: 0.75 foot diameter orifice (no drywell) 4.76 cfs Infiltration capacity, perv, non swale: Capacity is adequate. 7.68 cfs Hydraulic Capacity of Drywell is Peak Q, remainder: 0 cfs 0.00 cfs Peak flow: 0.08 cfs Swale Infiltration Capacity: 0.0000 cfs Engcalcl-G-14 ~ ~ - Drainage Report, R.A. Bonucce--i Marietta at Su----ivan Deve--opment Spokane County, Was---iington Stateme t The following report was prepared under my direction. The contents are engineering opinions derived using procedures that meet industry and professional standards. This document was not prepared as a canstruction document. Alan E. Gav Professional Engineer Printed Naine Title Civil EnLyineer June 28, 2000 Title Date , N E. S C~'~ ~ ~ ~~J~~'r~ •2. .s~,,, ~ li~(►~ R`rCEIVED ~ Ju N 212000 ~ IT'-~iJ4 cSS 4 E^'~"' f V `Al- SPO NE COUNIY ENGINEER {EXPiFtE.ri 7--/f' C'(' 13 -~5 lp TECHCOnT, I~TC. Professional Engineers & Certified Cnvironmental Specialists • i'roject Managers Steel Detailers ~ . Dl.2.AINAGE REPORT ROBER7, A. =BONUCCELLI MARIETTA AT SULLIVAN INDUSTRIAL DEV.CLOPMENT . SPOKANE COUNTY, WASHINGTON Proposed improvements to the site at the extension of Marietta Road west of Sullivan Road, trigger the neeci for storm water runoff disposal improvernents by Spokane County regulation. The calculation sheets following this narrative include details of the analysis showing that the proposed drainage improvements are adequatc to control ninoff on the site for a 10-year event, and safely discharge runoff for larger events at a rate equivalent to or less than the discharge rate in the pre-developed condition for the site. Key assumptions made for the site include assuming that the soils are Garrison gravely loam and Garrison very stony loain with an effective permeability equal to or greater than 0.36 inch per hour (0.36"/hr.). Another key assumption is that the intensity-duration-frequency (IDF) curves for the site conform to the IDF curves for Spokane as published in Chart 34 of the Washington State Department of Transportation (WSDOT) Hydraulics Manual. The drainage areas in the development are designated by parcel and roadway. Parcel basins are shown as Parcel 1 through 9, with Parcel 4B being held in reserve for drainage. Roadway basins are designated as Marietta West, Marietta Middl e and Marietta East. These drainages are shown with these designations on the drainage and grading plans presented with this report, as well as the times of concentratian for Marietta West, Marietta Middle and Mai-ietta East. The Bowstring method was used to assure that the roadside swales will have adequate volwne to contain a ten year stornl event The existing hydrologic conditions for the site are undeveloped. The calculated peak runoff for the existing site, using the SCS method, follows: Q=(P - 0.25)2/ (P + 0.85), wherc: Q= runoff in cfs, P= total storm rainfall, S= potential abstraction in inches S= 1000/CN -10 CN = curve number In this case, the CN = 70, since the soil group is Garrison, an "B" hydrologic soil. The land use is approximately the same as pasture in fair condition, thus the 70 rating. S= 4.29 P= 3.04 inches in 24 hours for a 100 year ston-n. Q= 0.737 inches over the site. The site drainage basin is approximately the 19.3 acres of the site, since the drainage is bounded , , on the west by the old Caminco praperty, whi.ch slopes to tlie west, the north edge of the sitc. is the J'ohnson Nfathey praperty with its own hydralogic controls, the south edgc of the site is the ald Milwaukee Railroad right-of--way, aiid drains toward the south, and the east edge is SullivC111 Road. Therefore the total pre-developed runoff from a1OU year event is predicted to be 620,000 cubic feet. For the peak runoff, the hydraulic length is 1234 feet, which equates to ari equivalent area of 19.3 acres, Using t~e Typc TI stal7ax curve, the estlinated, peak runaff for a CN70 is 11 cfslin ofirunoff. This equates to 8.1 cfs allowable peak runo{'f. For a 10 year starm, F' _2. l2, and Q =0.287 inches aver the site; therefore the allowable peak runaff is 3.16 cfs for a1Dyear starrn. The predicted peak ailiaunt is 0 cfs for the SW and SE basins, unless a runoff-over- ice condition develops that fi Hs over 7400 cubic feet Qf stvrage, in which case up t0 3efs would be discharged thi-ough the overflow pi,pe in the soutbwest comer of the SW svvale. Bonuccelli Development Marietta & Sullivan 28-Jun-00 Stormwater Disposal Entire Site is One Parcel Drain to Individual Parcel 208 swales Areas Required: Resulting Landscaping Area: TOTAL TOTAL NET NET MAX. UNBUILD- MIN LOADING REQ. Sublot # Type III Type IV AREA ACRES AREA ACRES BUILDING ABLE PARKING DOCK AVAIL? SWALE Imp.Area acres 1 2892.5 0 83135 1,908517 80242.5 1.842114 32422.65 44094.76 1800 OK 6158.994 73907.93 1.696693 2 3499 0 229719 5,273623 226220 5.193297 137831.4 0 56235.15 3600 OK 16003.59 192043 4.408702 3 993.6 0 106456 2,443893 105462.4 2.421084 63873.6 26060.4 2700 OK 7502.33 90027.96 2,066758 4 203.1 0 78459 1.801171 78255.9 1.796508 47075.4 19206.74 1800 OK 5513.456 66161.47 1.518858 5 993.6 0 93875 2,155073 92881.4 2.132264 56325 22980.58 1800 OK 6567.293 78807.52 1.809172 6 950 950 94052 2,159137 92152 2.115519 56431.2 23023.91 1800 OK 6579.393 78952.72 1.812565 7 1003.05 1250 50000 1,147842 47746.95 1.696119 20000 27199.97 360 OK 3736.665 44839.98 1.029384 8 706 0 35000 0.803489 34300 0.78742 14000 19039.98 360 OK 2624,665 31495.98 0.723048 9 1973.55 0 38135 0.875459 36161.45 0.830153 14872.65 20226.78 360 OK 2786,396 33436.76 0.767602 ROADWAY 0 0 37708 0.865657 37708 0.865657 0 0 0 NA 3142.333 37708 0.865657 SWSwale: 3255 0 74739 1.715771 71484 1.641041 0 0 0 0 TOTAL: 921278 21.14963 TOTAL: 60615.11 SQ. FT. 15.17952 r ; Bonuccelli Development Marietta & Sullivan 28-J u n-00 Stormwater Disposal Bowstring Method Calculation, Roadside Swale Capacity, Marietta Area 1: West End, Marietta Swale Area: 1600.588 square feet Volume: 1997.27 625.5295 1997.52 1113.059 217.3236 cu.ft. 1997.77 1600.588 556.5295 cu.ft. Pond Infiltration Rate: 0.005213 cfs Drywell Infiltration Rate; 0.3 cfs (Garrison Gravelly loam) No. of Drywells: 2 Drywell Volume: 108.9 cubic feet Total Available Storage Volulme: 665.4295 cubic feet Use Bowstring Method to check adequacy of Swale: Time increment; 5 min. Time of Concentration: 5.5 min. Storage req.: Outflow (c.f.s.) 0.61 cfs 208.6178 cf. Design year flow 10 year Area (acres) 0.36 Developed C factor: 0.848902 Area x C 0.31 No.1 No.2 No.3 No.4 No.S No.6 No.7 Time Inc. t Intensity Q dev. V in V out Storage No. 1 x 60 (in./hr) A*C*No.3 Out * No.2 5 300 3.18 0.970601 390.1816 181.5638 208.6178 10 600 2.24 0.683694 411.4948 363.1276 48.36711 15 900 1.77 0.54024 487.2264 544.6915 -57.46508 20 1200 1.45 0.44257 531.9111 726.2553 -194.3441 25 1500 1.21 0.369317 554.6657 907.8191 -353.1534 30 1800 1.04 0.317429 571.9662 1089.383 -517.4167 35 2100 0.91 0.277751 583.7956 1270.947 -687.1511 This is the worst-case area; no further analysis is necessary. Bonuccelli Development Industrial Development at Sullivan and Marietta 28-Jun-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Use conservative 5 min. intensity i= 3.2 in/hr Disposal Capacity: ' Garrison Gravelly LoamNery Stony Loam Soil Estimated TurF Infiltration Capacity q= 0.36 m/hr Ratio of i/q 8.888889 Maximum Storage Depth: 6 in. 10 year, one hour intensity: 3.2 inlhr 10 year, 24 hour total: 2.12 in. Parcel 1 Drain Basin Total Improved Impervious Surface Area: 73907.93 square feet Asphalt Impervious Surface Area: new: 39281 square feet Roof: direct: 32422.65 square feet Sidewalk: new: 2204.738 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 9227.066 square feet Depressed Infiltration Area: 6158.994 square feet cultivated surface Additional available infiltration volume on side slopes: Perimeter 6" above bottom 470.8756 square feet additional on slopes Total Available for Infiltration: 6629.87 square fee = 3197.216 ft3 Total Required Under County Standard: 1636.689 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year slorm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C. 0.25 10-year intensity: 3.2 in/hour Time of concentration: 3.65 min. Area Impervious: 73907.93 square feel Area Pervious. 9227.066 square feet Peak Q: 5.06 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale: 2597.196 square feet Peak Q, perv, non-swale: 0.05 cfs Infiltration capacity, perv, non swale: 0.02 cfs Engcalcl-G-1 Bonuccelli Development Industrial Development at Sullivan and Marietta 28-Jun-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Peak Q, remainder: 5.03 cfs Swale Infiltration Capacity: - 0.0552 cfs drywell infiltration cap.: 0 3 cfs each (1 total) Storage Required, 5 minute Storm: 1403 71 cubic feet Storage Available, Swale Only: 3197.216 cubic feet Plus Drywells: 54.45 cubic feet Total: 3251.67 cubic feet OK Peak Runoff, 50-year storm: (5 minute) 50-year intensity: 5.1 inlhour Peak Q: 8.06 cfs Storage Required: 2394.30 cubic feet Swale Plus Drywell: 3251.67 cubic feet OK Parcel 2 Orain Basin Total Improved Impervious Surface Area: 192043 square feet Asphalt Impervious Surface Area: new: 51400 square feet Roof. direct: 137831.4 square feet Sidewalk: new: 2811.758 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 37675.96 square feet Depressed Infiltration Area: 16003.59 square feet cultivated surface Additional available infiltration volume on side slopes: Perimeter 6" above bottom 759.0317 square feet additional on slopes Total Available for Infiltration: 16762.62 square fee = 8191.551 fl3 Total Required Under County Standard: 2141.662 ft3 OK Hydrology Check: Rational Method, Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C. 0.25 10-year intensity- 1.95 in/hour Time of concentration: 13 min. Area Impervious: 192043 square feet Area Pervious: 37675.96 square feet Peak Q: 8.16 cfs Peak Infiltration Rate: 0.36 inlhour Pervious Surface, non-swale. 20913.34 square feet Engcalcl-G-2 Bonuccelli Development Industrial Development at Sullivan and Marietta 28-Jun-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Peak Q, perv, non-swate: 0.23 cfs Infiltration capacity, pero, non swale: 0.17 cfs Peak Q, remainder: 7.98 cfs „ Swale Infillration Capacity: 0.1397 cfs drywell infiltration cap.: 0.3 cfs each (1 total) Storage Required, 13 minute Storm: 5885.06 cubic feet Storage Available, Swale Only: 8191.551 cubic feet Plus Drywells: 54.45 cubic feet Total: 8246.006 cubic feet OK Peak Runoff, 50-year storm: (13 minute) 50-year intensity: 2.7 inlhour Peak Q- 11.30 cfs Storage Required: 8751 66 cubic feet Swale Plus Drywell: 8246.006 cubic feet NG Storage Available, 12": 16762.62 cubic feet OK Parcel 3 Drain Basin Total Improved Impervious Surface Area- 90027.96 square feet Asphalt Impervious Surface Area: new: 24851 square feet Roof: direct: 63873.6 square feet , Sidewalk: new: 1303.02 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 16428.04 square feet Depressed Infiltration Area 7502.33 square feet cultivated surface Addiiional available infiltration volume on side slopes: Perimeter 6" above bottom 519.696 square feet additional on slopes Total Available for Infiltration: 8022.026 square fee = 3881.089 ft3 Total Required Under Counly Standard: 1035.473 ft3 OK Hydrology Check. Rational Method: Peak Runoff, 10-year storm, Q=CIA Irnpervious Surface C: 0.9 Pervious Surface C: 0.25 10-year intensity: 3.2 in/hour Time of concentration: 4.6 min. Area Impervious: 90027.96 square feet Area Pervious: 16428.04 square feet Engcalcl-G-3 Bonuccelli Developmeni Industrial Development at Suilwan and Marietta 28-Jun-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Peak Q: 6.25 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale: 8406.011 square feet Peak Q, perv, non-swale. 0.15 cfs Infiltration capacity, perv, non swale: 0.07 cfs Peak Q, remainder: 6_18 cfs Swale InfiltraLion Capacity: 0.0669 cfs drywell infiltration cap.: 0.3 cfs each (1 total) Storage Required, 5 minute Storm: 1745.12 cubic feet Storage Available, Swale Only: 3881.089 cubic feet Plus Orywells: 54.45 cubic feet Total: 3935.543 cubic feet OK Peak Runoff, 50-year storm: (5 minute) 50-year intensity: 5.1 in/hour Peak Q: 9.97 cfs Storage Required: 2967.11 cubic feet Swale Plus Drywell 3935.543 cubic feet OK Parcel 4 Drain Basin Total Improved Impervious Surface Area: 66161.47 square feet Asphalt Impervious Surface Area: new: 18126 square feet Roof: direct: 47075.4 square feet Sidewalk: new: 960.3372 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 12297.53 square feet Depressed Infiltration Area: 5513.456 square feet cultivated surface Additional available infiltration volume on side slopes. Perimeter 6" above bottom 445.5159 square feet additional on slopes Total Available for Infiltration: 5958.972 square fee = 2868.107 ft3 Total Required Under County Standard: 755.2388 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 Engcalc 1-G-4 Bonuccelli Development Industrial Development at Sullivan and Marietta 28-Jun-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). 10-year intensity: 2.5 in/hour Time of concentration. 8 min Area Impervious: 66161.47 square feet Area Pervious: 12297.53 square feet Peak Q. 3.59 cfs Peak Infiltration Rate: 0.36 inlhour Pervious Surface, non-swale: 6338.559 square feet Peak Q, perv, non-swale: 0.09 cfs Infiltration capacity, perv, non swale: 0.05 cfs Peak Q, remainder: ' 3.54 cfs Swale Infiltration Capacity: 0.0497 cfs drywell infiltration cap.: 0.3 cfs each (1 total) Storage Required, 8 minule Storm: 1531.87 cubic feet Storage Available, Swale Only: 2868.107 cubic feet Plus Drywells: 54.45 cubic feet Total: 2922.561 cubic feet OK Peak Runoff, 50-year storm: (8 minute) 50-year intensity: 3.65 in/hour Peak Q: 5.25 cfs Storage Required: 2481.68 cubic feet Swale Plus Drywell: 2922.561 cubic feet OK Parcel 5 Drain Basin Total Improved Impervious Surface Area: 78807.52 square feet Asphalt Impervious Surface Area: new: 21333 square feet Roof: direct. 56325 square feet Sidewalk: new: 1149 029 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 15067.48 square feet Depressed Infiltration Area: 6567.293 square feet cultivated surface Additional available infiltration volume on side slopes: Perimeter 6" above bottom 486.233 square feet additional on slopes ' Total Available for Infiltration: 7053.526 square fee = 3405.205 0 Total Required Under County Standard: 888.8954 ft3 OK Hydrology Check: Engcalc1-G-5 Banuccelli Development Industrial ❑euelopment at Sullivan and Marietka 28 -J u n-40 TechCon, Inc. Prepared by Alan E. Gay, P E ' Site Nydrology Study Qesign ko 10 year skarm (for review by 5pokane County Engineers). Raiional Method: Peak Runoff, 10-year storrri, Q=CfA Imperviaus Surface C: 0.9 I'ervious Surface C: 0.25 10-year infensity: 2.6 inlhour Z'ime of concentration: 7.5 min. Area Imperv~ous- 78807_52 square feet Area Pervious: 15067_48 square feet Peak 0: 4.46 cfs Peak Infdtration Rate: 0,36 irilhour Pervious Surface. nan-swale: 8011954 square feet Peak Q, perv, nan-swale; 0.12 cfs Irrfiltratian capacity, perv, nan swaCe: 0. DT cfs Peak Q, rernsinder 4,39 cfs 5wale Infilkration Capacity: O.f1588 cFs drywell infltra#iQn cap_• 0_3 efs each (1 totai) Storage Required, 7.5 minute Storm: 1814. 73 cubic feet Statage Available, Swale Qnly: 3405.205 cubic feet Plus mrywells- 54.45 cubic feet Tc,tal- 3459.659 cuhic feet OK f'eak RunoTf, 50-year storarti; (7.5 minute) 50-year intensity: 3,8 inlhour Peak 6,52 cfs Sforage Required; 289769 cubic feet Swale Plus Dryavelf: , 3459,659 cubic feet OIC Parcel 6 Drain Basin Tokal lrnpeaved Impervious Surface Area: 78952_72 square feet Asphalt lmpervious Surface Area: new~ 21370 square feet Rovf, direci: 56431.2 square feet Sidew~lk, new• 1151.195 square feet l.Ffilize biofiltra tidn swa le (grassy) far disposa l. Assu me an#ecedant saturated soiE cpndition5; Uttlize Spokane Counfy Type A drywelis for overFlow. Include storage volume of drywe3ls as well as dryvrelE infiitratian capacity. Available Grassy Area; 15099.28 square feet Depressed Infltratic►n Area: 6579.393 square feet cultiVated surface Additional avaiEable infl'tration valume on side slopes: PeffTnetef 6'~ ab41+E b4ttpfT1 486.6807 square feet additional on slopes Total Available for InfFlkration: Engcalcl-G-15 Bonuccelli Development Industrial Development at Sullivan and Marietta 28-Jun-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). 7066.074 square fee = 3411.367 ft3 Total Required Under County Standard: 890.43 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year intensity- 2.6 inlhour , Time of concentration: 7.5 min. Area Impenrious: 78952.72 square feet Area Pervious: 15099.28 square feet Peak Q: 4.47 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale: 803321 square feel Peak Q, perv, non-swale: 0.12 cfs Infiltration capacity, perv, non swale: 0.07 cfs Peak Q, remainder: 4 40 Cfs Swale Infiltration Capacity: 0.0589 cfs drywell infiltration cap.: 0.3 cfs each (1 total) Storage Required, 7.5 minute Storm: 1818.34 cubic feet Storage Available, Swale Only: 3411.367 cubic feet Plus Drywells: 54.45 cubic feet Total: 3465.821 cubic feet OK Peak Runoff, 50-year storm: (7.5 minute) 50-year intensity: 3.8 inlhour Peak Q: 6.53 cfs Storage Required: 2903.03 cubic feet Swale Plus Drywell: 3465.821 cubic feet OK Parcel 7 Drain Basin Total Improved Impervious Surface Area: 44839.98 square feet Asphalt Impervious Surface Area: new: 23480 square feet Roof: direct: 20000 square feet Sidewalk: new: 1359.999 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions. Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 5160.024 square feet Depressed Infiltration Area: 3736.665 square feet cultivated surface Engcalc1-G-7 4 , BOnUCCelli Development Industrial Qevelopment at Sulliwan and Marietta 28-Jun-O0 TechCfln, Enc. Prepared by Alan E Gay, P.E. Site Hydralagy Skudy Design ta 14 year starm (for review by Spokane County F-nginee rs)- PadditGOnai available Gnfiltration wolume on side siopes; , Perimeter 6" above botlom 366 7696 square feet additianai an slapes Tatal Available fnr InFiltration: 4103.434 square fee = 1960.025 ft3 Total Required Ursder Caunty Standard: 978.3324 ft3 Olf Nydroingy Check: Rational Mekhod: Peak RunofP, 1 Q-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface G: 0.25 10-year in tensity: 3_2 inlhour Time af concenttation. 3 min. Area Irnpervious~ 44839.98 square feet Area Pervious; 5160.024 square feet Peak 0; 106 cfs Re2k Infilkration Rate- 0-36 inlhour Pervious Surface, nan-swale: 105659 square feet Pea4c Q, perv, non-swale: 002 cfs Infiltration capacity, Perv, non swale. 0.[}1 cfs Peak Q, remainder, 3.05 cfs 5wale Infiltration Capacity: 0_0342 crs drywell infiltration cap.: 0.3 efs each (111 total) Storage Required, 5 rninute Starm: 814_92 cubic feek S#orage AvaiCable, Swale flnly: 196{}.025 cubic feet Plus [7rywelis- 54_45 cubic feet Total, 2014,479 cubic feet OK Peak Runoff, 50-year starm: (5 mmute) 50-year intensity: 5.1 inlhour Peak Q' 4 88 cis Stvrage Requ~red; 1439.70 cubic Fee# Swale Plus arywefl: 2074_479 cubic fee# OK Parc$I 8 Drain Basin Total Improwed Irnpervious Surfaae Area; • 31495.98 square feet Asphalt Impervious Surface Area: new: 16544 square feet . F2nof: direct: 14044 square feet Sidewalk: new, 951,999 square feet Utilize 6iofiEtration swale (grassy) fordisposal. Assume anxecedant saturated saif corditions: Utilize Spokane County Type A drywells for overflQw. lnclude storage volume of drywefls as well as drywell infiltration capacwty. E ngca Ic l-G-B Bonuccelli Development Industrial Development at Sullivan and Marietta 28-Jun-00 TechCon, Inc Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Available Grassy Area. 3504.017 square feet Depressed Infiltration Area: 2624.665 square feet cultivated surface Additional available infiltration volume on side slopes: Perimeter 6" above bottom 307.3889 square feet additional on slopes Total Available for Infiltration: 2932.054 square fee = 1389.18 1`13 Total Required Under County Standard: 689.3327 ft3 OK Hydrology Check: Rational Method. Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year intensity: 3.2 in/hour Time of concentration: 5 min. Area Impervious: 31495.98 square feet Area Pervious: 3504.017 square feet Peak Q: 2.15 cfs Peak Infiltration Rate: 0.36 inlhour Pervious Surface, non-swale: 571.963 square feet Peak Q, perv, non•swale: 0 01 cfs Infiltration capacity, perv, non swale. 0.00 cfs Peak Q, remainder: 2.14 cfs Swale Infiltration Capacity: 0.0244 cfs drywell infiltration cap.- 0.3 cfs each (1 total) Storage Required, 5 minute Storm: 545.26 cubic feet Storage Available, Swale Only: , 1389 18 cubic feet Plus Drywells: 54.45 cubic feet Total: 1443.634 cubic feet OK Peak Runoff, 50-year storm: (5 minute) 50-year intensity: 5.1 in/hour Peak Q: 3.42 cfs Storage Required: 1003.34 cubic feet Swale Plus Drywell. 1443.634 cubic feet OK Parcel 9 Drain Basin Total Improved Impervious Surface Area: 33436.76 square feet Asphalt Impervious Surface Area: new: 17553 square feet Roof: direct: 14872.65 square feet Sidewalk: Engcalc1-G-9 Bonuccelli Development Industrial Development at Sullivan and Marietta 28-Jun-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). new: 1011.339 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as • well as drywell infiltration capacity. Available Grassy Area. 4698.245 square feet Depressed Infiltration Area: 2786.396 square feet cultivated surface Additional available infiltration volume on side slopes: Perimeter 6" above bottom 316.718 square feet addilional on slopes Total Available for Infillration: 3103.114 square fee = 1472.378 0 Total Required Under County Standard: 731.3653 ft3 OK Hydrology Check: Rational Method. Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year intensity: 3.2 in/hour Time of concentration: 5 min. Area Impervious• 33436.76 square feet Area Pervious: 4698245 square feet Peak Q: 2.30 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale: 1595.13 square feet Peak Q, pero, non-swale. 0 03 cfs Infiltration capacity, perv, non swale: 0.01 cfs Peak Q, remainder: 2.28 cfs Swale Infiltration Capacity: 0.0259 cfs drywell infiltration cap : 0.3 cfs each (1 total) Storage Required, 5 minute Storm: 587.35 cubic feet Storage Available, Swale Only: 1472.378 cubic feet Plus Drywells: 54.45 cubic feet Total: 1526.832 cubic feet OK Peak Runof#, 50-year storm: (5 minute) 50-year intensity: 5.1 inlhour Peak Q: 3.66 cfs Storage Required: 1075.18 cubic feet Swale Plus Drywell• 1526.832 cubic feet OK Roadway Basins: West End, North and South Sides: (Mirror Images) Total Improved Impervious Surface Area: 7030.648 square feet Asphalt Impervious Surface Area: Engcalcl-G-10 Bonuccelli Development Industrial Development at Sullivan and Marietta 28-Jun-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study ' Design to 10 year storm (for review by Spokane County Engineers). new: 5544.86 square feet Roof: new: 0 square feet Sidewalk: new: 1485.785 square feet Utilize biofillration swale (grassy) for disposal. Assume antecedant saturated soil conditions: 1 Drywell necessary Available Grassy Area: 800.2942 square feet Depressed Infiltration Area: 312.7647 square feet cultivated surface Additional available infiltration volume on side slopes. Assume 3:1 slopes 1.5 feet wide strip around depression Swale. 487.5295 square feet: up to 6" available for storage on 3:1 slopes Tolal Available for Infiltration: North: 800 2942 square fee = 231.8873 ft3 Total Required Under County Standard: 231.0359 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year intensity: 3.2 in/hour Time of concentration: 1 min. Area Impervious: 7030.648 square feet Area Pervious. 800.2942 square feet Peak Q: 0.48 cfs Peak Infiltration Rate: 0.36 inlhour Pervious Surface, non-swale. 0 square feet Peak Q, perv, non-swale: 0.00 cfs Infiltration capacity, perv, non swale: 0.00 cfs Peak Q, remainder: 0.48 cfs Swale Infiltration Capacity: 0.0067 cfs Drywell infiltratin cap.: 0.3 cfs Storage Required, 5 minute Storm: 51.86 cubic feet Storage Avadable, Swale Only: 231.8873 cubic feet Plus Drywell: 54.45 cubic feet Total: 286.3416 cubic feet OK Peak Runoff, 50-year storm: (5 minute) 50-year intensity: 5.1 in/hour Peak Q: 0.76 cfs Storage Required: 137.28 cubic feet OK ' Roadway Basins: Middle, North and South Sides: (Mirror Images) Engcalcl-G-11 Bonuccelli Development Industrial Development at Sullivan and Manetta 28-Jun-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Total Improved Impervious Surface Area: 5200 square feet Asphalt Impervious Surface Area: new: 4000 square feet Roof: new: 0 square feet Sidewalk: new: 1200 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: no drywell necessary Available Grassy Area: 456 square feet Depressed Infiltration Area: 228 square feet cultivated surface Additional available infiltration volume on side slopes: Assume 3:1 slopes 1.5 feet wide strip around depression Swale: 228 square feet: up to 6" available for storage on 3:1 slopes Total Available for Infiltration: North: 456 square fee = 171 ft3 Total Required Under Couniy Standard- 166.6667 ft3 OK Hydrology Check: Rational Melhod: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Peroious Surface C: 0.25 10-year iniensity: 3.2 in/hour Time of concentration: 2 min. Area Imperoious: 5200 square feet Area Pervious: 456 square feet Peak Q: 0.35 cfs Peak Infiltration Rate. 0.36 in/hour Pervious Surface, non-swale: 0 square feet Peak Q, perv, non-swale: 0.00 cfs Infiltration capacity, perv, non swale: 0.00 cfs Peak Q, remainder. 0.35 cfs Swale Infiltration Capacity: 0.0038 cfs Drywell infiltratin cap.: 0 cfs Storage Required, 5 minute Storm: 104.51 cubic feet Storage Available, Swale Only: 171 cubic feet Plus Drywell: 0.00 cubic feet Total: 171 cubic feet OK Peak Runoff, 50-year storm: (5 minute) 50-year intensity: 5.1 in/hour Peak Q: 0.56 cfs Storage Required: Engcalcl-G-12 Bonuccelli Development Industrial Development at Sullivan and Marietta 28-Jun-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). 167.24 cubic feet OK Roadway Basins: East End, North and South Sides: (Mirror Images) Total Improved Impervious Surface Area. 4314.18 square feet Asphalt Impervious Surface Area: new: 3319 square feet Roof: new: 0 square feet Sidewalk: new: 995.58 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: 1 Drywell Available Grassy Area: 1200 square feet Depressed Infiltration Area: 600 square feet cultivated surface Additional available infiltration volume on side slopes: Assume 3:1 slopes 1.5 feet wide strip around depression Swale: 600 square feet: up to 6" available for storage on 3:1 slopes Total Available for Infiltration: North: 1200 square fee = 450 ft3 Total Required Under County Standard: 138.275 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year intensity: 3.2 in/hour Time of concentration: 1 min. Area Impervious: 4314.18 square feet Area Pervious: 1200 square feet Peak Q: 0.31 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale: 0 square feet Peak Q, perv, non-swale: 0.00 cfs Infiltration capacity, perv, non swale: 0.00 cfs Peak Q, remainder: 0.31 cfs Swale Infiltration Capacity: 0.0100 cfs Drywell infiltratin cap.: 0 cfs Storage Required, 5 minute Slorm: 91.04 cubic feet Storage Available, Swale Only: 450 cubic feet Plus Drywell: 0.00 cubic feet Total: 450 cubic feet OK Peak Runoff, 50-year storm: (5 minute) Engcalc1-G-13 a Bonuccelli Development Industrial Development at Sullivan and Marietta 28-Jun-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). 50-year intensity: 5.1 in/hour Peak Q: 0.49 cfs Storage Required: 145.78 cubic feet OK Existing Pre-tieveloped Site Total Improved Impervious Surface Area: 0 square feet Asphalt Impervious Surface Area: new: 0 square feet Roof: new: 0 square feet Sidewalk: new: 0 square feet Available Grassy Area: 921278 square feet Depressed Infiltration Area: 0 square feet cultivated surface Additional available infiltration volume on side slopes: Assume 3:1 slopes 0 feet wide strip around depression Swale: 0 square feet: up to 6" available for storage on 3:1 slopes Total Available for Infiltration: NoRh: 0 square fee = 0 ft3 Total Required Under County Standard: 0 ft3 OK Hydrology Check: Rational Method: SCS Method : Peak Runoff, 10-year storm, Q=CIA 24 hour storm Impervious Surface C: 0.9 Tc = 25.26 minutes Pervious Su►face C: 0.25 Total Area 21.15 acres 10-year intensity: 0.9 in/hour Time of concentration: 36.2 min. Area Impervious: 0 square feet SCS curve No. 61 Area Pervious: 921278 square feet 10-year 24 hour storm: Peak Q: 4.76 cfs 2.12 inches SCS Type II Storm Peak Infiltration Rate: 0.36 in/hour SCS 100 Hydrograph Pervious Surface, non-swale: 921278 square feet simulate capacity of drywell as Peak Q, perv, non-swale: 0.75 foot diameter orifice (no drywell) 4.76 cfs Infiltration capacity, perv, non swale: Capacity is adequate. 7.68 cfs Hydraulic Capacity of Drywell is Peak Q, remainder: 0 cfs 0.00 cfs Peak flow: 0.08 cfs Swale Infiltration Capacity: 0.0000 cfs Engcalcl-G-14 / v '2~~ ~ CL~s-'IENT PLANNiNG oI!lISi()pq Drainage Report, R.A. Bonucce-----i Marietta at Su----ivanDe've--opment Spokane County, Washington Statement The following report was prepared under my direction. The contents are engineerinb opinions derived using procedures that meet industry and professional standards. This document was not prepared as a construction document. Alan E. Gav Prafessional En2ineer Printed 1Waine Title Civil En2ineer Mav 16, 2000 Title Date p', d~~h~_ ; ~ .r ~ { I~~~u •Y•+~ ~'1f.'iy~~' ~y•t ~ f t~ % I'O. ~C,~'~ F1 tv~ . .,^,•T'^ 4 ~~,•~Y •;i~ spO "7~ * f.~.,i ' ~ ~ `~r~ ~ • C~,~~ rCj~, rs~i~.~~• ~ ! t;K s S•IONAL E Y f'I R FS ~I ~J U` '~f14~~ ( ~ TECI-ICON, INC. Professional Engineers • Certified Cnvironmental Specialists • I'roject Managers • Steel Detailers . } DRAINA.GE REPORT ROBERT A. BON UCCELLI MARIETTA AT SULLTVAN INDUSTitIAL DEVELOPMENT SPOKANE COUNTY, WASHINGTON Proposed improvements to the site at the extension of Marietta Road west of Sullivan Road, trigger the need for stornl water runoff ciisposal improvements by Spokane County regulation. The calculation sheets following this narrative inclucle details of the analysis showing that the proposed drainage improvements are adequate to control runoff on the site for a 10-year event, and safely discharge runoff for larger events at a rate equivalent to or less than the discharge rate in thc prc-developed condition for the site. Key assumptions made for the site include assuming that the soils are Garrison gravely loaln with an effective permeability equal to or greater than 0.36 inch per hour (0.36"/hr.). Another key assumption is that the intensity-duration-frequency (IDF) curves for the site conforin to the rDF curves for Spokane as published in Chart 34 of the Washington State Departrnent of Transportation (WSDOT) Hydraulics Manual. The two drainage areas in the developmcnt are designated "Southwest (SW)", and "Southeast (SE)". Tliese drainages are shown with thesc designations on the drainage and grading plans presented with this report. The SCS TR55 method analysis was performed using SMADA software produced by the University of Central Florida. In both of the swales, the controlling volumc requit-ement is derived from the SCS method. Both of the basin swales meet or exceed the Spokanc County's minimum requirement for 208 infiltration area and on-site storage volume. The existing hydi-ologic conditions for thc site are undeveloped. The calculated peak runoff for the existing site, using the SCS method, follows: Q=(P - 0.2 S)Z /(P + 0. S S), where: Q= runoff in cfs, P= total stonn rainfall, S= potential abstraction in inches S= 1000/CN -10 CN = curve number In this case, the CN = 70, since the soil group is Garrison, an "B" hydrologic soil. The land use is approxiYnately the same as pasture in faii• condition, thus the 70 rating. S= 4.29 P= 3.04 inches in 24 hours for a 100 yeat• stortn. Q= 0.737 inches over the site. . w The site drainage basin is approximately the 19.3 acres of tlle site, since the drainage is boundeci on the west by the old Cominco property, which slopes to the west, the north edge of the site is the Johnson Mathey property with its own hydrologic controls, the south edge of the site is the old Milwaukee Railroad right-of-way, and drains toward the south, and the east edge is Sullivan Road. Therefore the total pre-developed runoff from a 100 year event is predicted to be 620,000 cubic feet. For the peak runoff, the hydraulic length is 1234 feet, which eyuates to an equivalent area of 19.3 acres. Using the Type II storm curve, thc estimated peak runoff for a CN70 is 11 cfs/in of runoff. This equates to 8.1 cfs allowable peak runoff. For a 10 year stonn, P= 2.12, and Q= 0.287 inches over the site; therefore the allowable peak runoff_ is 3.16 cfs for a 10 year storni. The predicted peak amounfi is 0 cfs for the SW and SE basins, unless a runoff-over- ice condition develops that fills over 7000 cubic f.eet of storage, in which case up to 3 cfs would be discharged through the overflow pipe in the southwest corner of the SW swale. • } Bonuccelli Development Industrial Development at Sullivan and Marietta 16-May-00 TechCon, Inc. • Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Use conservative 5 min. intensity i= 3.2 in/hr Disposal Capacity: Garrison Gravelly Loam Soil ' Estimated Turf Infiltration Capacity q= 0.36 in/hr Ratio of i/q 8.888889 Maximum Storage Depth: 6 in. 10 year, one hour intensity: 3.2 in/hr 10 year, 24 hour total: 2.12 in. New Drain Basin SouthWest: Total Improved Impervious Surface Area: 597193.3 square feet Asphalt Impervious Surface Area: new: 195728 square feet Roof: direct: 347135 square feet Sidewalk: new: 54330.18 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 113226.8 square feet Depressed Infiltration Area: 47801 square feet cultivated surface Additional available infiltration volume on side slopes: Perimeter 6" above bottom 1471.5 square feet additional on slopes Total Available for Infiltration, 49272.5 square fee, = 24268.38 ft3 Total Required Under County Standard: 8155.337 ft3 OK Hydrology Check: Rational Method: SCS Method : Peak Runoff, 10-year storm, Q=CIA 24 hour storm Impenrious Surface C: 0.9 Tc = 11.70 minutes Pervious Surface C: 0.25 Total Area 16.309 acres 10-year intensity: 3.2 in/hour Time of concentration: 5.94 min. Area Impervious: 597193.3 square feet SCS curve No. 92 Area Pervious: 113226.8 square feet 10-year 24 hour storm: Peak Q: 41.56 cfs 2.12 inches SCS Type II Storm Peak Infiltration Rate: 0.36 in/hour SCS 100 Hydrograph Pervious Surface, non-swale: 63954.28 square feet simulate capacity of drywell as Peak Q, perv, non-swale: .75 foot diameter orifice 1.17 cfs Engcalcl-G-1 . dr Bonuccelli Developmenl Industrial Development at Sullivan and Marietta 16-May-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Infiltration capacity, perv, non swale: Capacity is adequate. 0.53 cfs Hydraulic Capacity of Drywell is Peak Q, remainder: 1.2 cfs 41.03 cfs Peak flow: 9.66 cfs Swale Infiltration Capacily: Greatest Depth: 1.1 feet 0.4106 cfs OK drywell infiltration cap.: 0.3 cfs each (4 total) Storage Required, 5 minute Storm: 12095.93 cubic feet Storage Available, Swale Only: 24268.38 cubic feet Plus Drywells: 217.82 cubic feet Total: 24486.19 cubic feet OK Peak Runoff, 50-year storm: (5 minute) 50-year intensity: 5.1 in/hour Peak Q: 66.24 cfs Storage Required: 19589.39 cubic feet Swale Plus Drywell: 24486.19 cubic feet OK New Drain Basin SouthEast Total Improved Impervious Surface Area: 149426.8 square feet Asphalt Impervious Surface Area: parking: 51113 square feet Roof: new: 95696.89 square feet Sidewalk: new: 2616.547 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 23730.14 square feet Depressed Infiltration Area: 7607 square feet cultivated surface Additional available infiltration volume on side slopes: Assume 3:1 slopes 1.5 feet wide strip around depression ' Swale: 779.715 square feet: up to 6" available for storage on 3:1 slopes Total Available for Infiltration: North: 8386.715 square fee, = 3998.429 ft3 Total Required Under County Standard: 2129.724 ft3 OK Hydrology Check: Rational Method: SCS Method : Peak Runoff, 10-year storm, Q=CIA 24 hour storm Impervious Surface C: 0.9 Tc = 5.94 minutes Pervious Surface C: 0.25 Total Area 3.975 acres 10-year intensity: 3.2 in/hour Time of concentration: 1.67 min. Area Impervious: 149426.8 square feet SCS curve No. 93 Engcalc1-G-2 . , Bonuccelli Development Industrial Development at Sullivan and Marietta 16-May-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Area Pervious: 23730.14 square feet 10-year 24 hour storm: Peak Q: 10.32 cfs 2.12 inches SCS Type II Storm Peak Infiltration Rate: 0.36 in/hour SCS 100 Hydrograph Pervious Surface, non-swale: 15343.42 square feet simulate capacity of each drywell as Peak Q, perv, non-swale: .75 foot diameter orifice 0.28 cfs Infiltration capacity, perv, non swale: Capacity is adequate. 0.13 cfs Hydraulic Capacity of Drywell is Peak Q, remainder: 0.6 cfs 10.19 cfs Peak flow: 3.94 cfs Swale Infiltration Capacity: Greatest Depth: 1.28 feet - 0.0699 cfs OK Drywell infiltratin (ea): 0.3 cfs (two Type A drywells) Storage Required, 5 minute Storm: 2945.26 cubic feet Storage Available, Swale Only: 3998.429 cubic feet Plus Drywells: 108.91 cubic feet Total: 4107.337 cubic feet OK Peak Runoff, 50-year storm: (5 minute) 50-year intensity: 5.1 in/hour Peak Q: 16.44 cfs Storage Required: 4782.66 cubic feet Storage Available, 12": 8565.159 cubic feet OK Roadway Basins: West End, North and South Sides: (Mirror Images) Total Improved Impervious Surface Area: 12466.72 square feet Asphalt Impervious Surface Area: new: 9567 square feet Roof: new: 0 square feet Sidewalk: new: 2899.32 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: no drywell necessary Available Grassy Area: 2575.32 square feet Depressed Infiltration Area: 1164.8 square feet cultivated surface Additional available infiltration volume on side slopes: Assume 3:1 slopes 1.25 feet wide strip around depression Swale: 918.9625 square feet: up to 6" available for storage on 3:1 slopes Total Available for Infiltration: North: 2083.763 square fee, = 676.7839 ft3 Total Required Under County Standard: 398.6417 ft3 OK Hydrology Check: Rational Method: SCS Method : Engcalc1-G-3 . , Bonuccelli Developmenl Industrial Development at Sullivan and Marietta 16-May-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Peak Runoff, 10-year storm, Q=CIA 24 hour storm Impervious Surface C: 0.9 Tc = 5.80 minutes Pervious Surface C: 0.25 Total Area 0.345 acres 10-year intensily: 3.2 inlhour Time of concentration: 1 min. Area Impervious: 12466.72 square feet SCS curve No. 92 Area Pervious: 2575.32 square feet 10-year 24 hour storm: Peak Q: 0.87 cfs 2.12 inches SCS Type II Storm Peak Infiltration Rate: 0.36 in/hour SCS 100 Hydrograph Pervious Surface, non-swale: 491.5575 square feet simutate capacity of drywell as Peak Q, perv, non-swale: 0.75 foot diameter orifice 0.01 cfs Infiltration capacity, perv, non swale: Capacity is adequate. 0.00 cfs Hydraulic Capacity of Drywell is Peak Q, remainder: 0.3 cfs 0.87 cfs Peak flow: 0.34 cfs Swale Infiltration Capacity: Greatest Depth: 0.5 feet 0.0174 cfs OK Drywell infiltratin cap.: 0.3 cfs . Storage Required, 5 minute Storm: 112.14 cubic feet Storage Available, Swale Only: 676.7839 cubic feet Plus Drywell: 54.45 cubic feet Total. 731.2381 cubic feet OK Peak Runoff, 50-year storm: (5 minute) 50-year intensity: 5.1 iNhour Peak Q: 1.39 cfs Storage Required: 267.38 cubic feet OK - Roadway Basins: East End, North and South Sides: (Mirror Images) Total Improved Impervious Surface Area- 5887.7 square feet Asphalt Impenrious Surface Area: new: 4529 square feet Roof: new: 0 square feet Sidewalk: new. 1358.7 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: • no drywell necessary Available Grassy Area: 1358.7 square feet Depressed Infiltration Area: 566.125 square feet cultivated surface Additional available infiltration volume on side slopes: Assume 3:1 slopes 1.5 feet wide strip around depression Swale: 566.125 square feet: up to 6" available for storage on 3:1 slopes Total Available for Infiltration: Engcalc1-G-4 . , Bonuccelli Development Induslrial Development at Sullivan and Marietta 16-May-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). North: 1132.25 square fee = 424.5938 ft3 Total Required Under Couniy Standard: 188.7083 ft3 OK Hydrology Check: Rational Method: SCS Method : Peak Runoff, 10-year storm, Q=CIA 24 hour storm Impervious Surface C: 0.9 Tc = 5.50 minutes Pervious Surface C: 0.25 Total Area 0.166 acres 10-year intensity: 3.2 in/hour Time of concentration: 1 min. Area Impervious: 5887.7 square feet SCS curve No. 91 Area Pervious: 1358.7 square feet 10-year 24 hour storm: Peak Q: 0.41 cfs 2.12 inches SCS Type II Storm Peak Infiltration Rate: 0.36 in/hour SCS 100 Hydrograph Pervious Surface, non-swale: 226.45 square feet simulate capacity of drywell as Peak Q, perv, non-swale: 0.75 foot diameter orifice 0.00 cfs Infiltration capacity, perv, non swale: Capacity is adequate. 0.00 cfs Hydraulic Capacity of Drywell is Peak Q, remainder: 0.3 cfs 0.41 cfs Peak flow: 0.16 cfs Swale Infiltration Capacity: Greatest Depth: 0.5 0.0094 cfs OK Drywell infiltratin cap.: 0.3 cfs Storage Required, 5 minute Storm: 30.87 cubic feet Storage Available, Swale Only: 424.5938 cubic feet Plus Drywell: 54.45 cubic feet Total: 479.048 cubic feet OK Peak Runoff, 50-year storm: (5 minute) 50-year intensity: 5.1 in/hour Peak Q: 0.66 cfs Storage Required: 104.65 cubic feet OK Existing Pre-developed Site Total Improved Impervious Surface Area: 0 square feet Asphalt Impervious Surface Area: new: 0 square feet Roof: new: 0 square feet Sidewalk: new: 0 square feet Available Grassy Area: 921278 square feet Depressed Infiltration Area: 0 square feet cultivated surface Additional available infiltration volume on side slopes: Engcalc1-G-5 . r gonuccelli ❑evelopment Industrial Qevelopment at 8ullivan and Mariefta 1G-May-a0 TechGon, Inc_ Arepared by Alan EGay, PZ. Siie Hydrology Skudy _ Design to 10 year storm {for reuiew by 5pokane County Engirreers}, Assume 31 sfopes 0 fee# wide strip arvund depressic n Swale: 0 square feet: L,p to fi" available for starage an 3:1 slopes Total Available #or Infil#ration: Nvrth: b square fee = 0 ft3 Tokal Required Under Counky Standard: 0 fl3 OK .Hydrology Check: Rational Method: 5CS dUiethod : Peak Runoif, 10-year storm, Q-C1,4 24 hoaar skorm impervious Surface C: 0,9 Tc = 25.25 rninukes Penrious Surface C- 0.25 Total Area 21.15 acres iQ-year intensity: 0.9 inlhaur Time vf concentra#ion: 36.2 min. Area fmpervivus: 0 square feet SC5 curve No. 69 Area Perviaus: 921279 square feet 10-year 24 hour storm- Peak Q: 4.76 cfs 2.12 inches SCS Type ll Skorm Peak Infiftration Rate: 0.36 infhour SCS 100 Hydrograph Pen+iQUS Surface, non-swafe- 921278 square feet simulake capacity af drywell as Peak Q, perv, non-swale: 0.7 5 foot diameter orifice (no d rywa fl) 4.76 cfs Infiltration capacity, perv, non swale: Capacity is adequate. 7.68 cfs Hydraulic Capacity af Orywefl is Peak Q, rerriainder: 0 cfs 0.00 cfs Peak flaw: (}.08 cfs Suaale Infltratian Capacity: 0.0000 cfs En9cafcl-C-6 Bonuccelli Development Marietta & Sullivan 16-May-00 Stormwater Disposal Entire Site is One Parcel Drain fo Two Centrai 208 swales Areas Required: Resulting Landscaping Area: TOTAL TOTAI NET NET MAX. UNBUILD- MIN LOAOING REQ. Sublot # Type III Type IV AREA ACRES AREA ACRES BUILDING ABLE PARKING DOCK AVAIL? SWALE Imp,Area acres 1 2892,5 • 4 83135 1.908517 80242.5 1.842114 32422.65 44094.76 1800 OK 6159.994 73907.93 1.696693 2 3499 0 229719 5.273623 226220 5.193297 137831.4 26345,37 56235.15 3600 OK 16003.59 192043 4.448702 3 993.6 0 106456 2.443893 105462.4 2.421084 63873.6 260604 2700 OK 7502.33 90027.96 2.066758 4 203.1 0 78459 1.801171 78255.9 1.796508 47075.4 19206.74 1800 OK 5513.456 66161.41 1.518858 5 993.6 0 93875 2.155073 92881.4 2132264 56325 22980 58 1800 OK 6567.293 78807.52 1.849172 6 950 950 94052 2.159137 92152 2.115519 56431.2 23023.91 1800 OK 6579.393 78952.72 1.812505 7 1003.05 1250 50000 1.147842 47746.95 1,096119 20000 21199.97 360 OK 3736.665 44839.98 1.029384 8 700 0 35000 0.803489 34300 0.78742 14000 19039.98 360 OK 2624.665 31495.98 0.723048 9 1973.55 0 35135 0.875459 36161.45 0.830153 14872.65 20226.78 360 OK 2186.396 33436.76 0.767602 ROADWAY 0 0 37708 0.865657 37708 0.865657 0 0 0 NA 3142.333 37708 0.865657 SWSWALE 3255 0 74739 1715771 71484 1.641047 SESWALE 0 0 ROADSWA 0 0 TOTAL: 921278 21.14963 TOTAL: 60615.11 SQ. FT. 15.17952 = 1.391532 Acres TO SWSWALE: 49533,82 SQ. FT. TO SESWALE: 11081.29 SQ. FT. SW AVAII: 52831.5 SQ. FT. ROUTE TO SE; 7783.613 SQ. FT. 5W5wale Basin Areas: TOTAL Landscape Parking Total Imperoious Rational scs cN Tatal Area: ACRES Area Landscape building paved loading unused' sf, acres 10-year 13.70967 98 1 44640.69 1.024809 2022 2342 17220 21077.79 954 1024.9 40174.2 0.922273 2.656145 0.883397 61 2 95056.37 2.182194 950 2339.354 57337.16 21054.18 1497.582 11878.09 90579.21 2.079412 5.988708 14.59307 95.76019 3 106456 2.443893 993.6 2606.04 63873.6 23454.36 2700 12828.4 101573.5 2.331807 6.715605 All siles-sife4 4 78459 1.801171 203.1 1920.674 47075.4 17286.07 1800 10173.76 75317.85 1.72906 4.979693 11.98461 98 5 93875 2.155073 993.6 2298.058 56325 20682.52 1800 11775.82 89405.76 2,052474 5.911125 0.811286 61 6 94052 2.159137 1900 2302,391 56431.2 20721.52 1800 10896.89 88159.92 2.037647 5.868424 12.7919 95.65339 7 50000 1.147842 2253.05 2719.997 20000 24479.98 360 186.9772 45008.26 1.033247 2.975752 Sites 6,7,8,9+Road 8 35000 0.803489 700 1903.998 14000 17135.98 360 900.019 32306 0.741644 2.135934 7.59633 98 9 38135 0.875459 1973.55 2022,678 14872.65 18204.11 360 702.0162 34068.57 0.782107 2.252467 0.5966 61 0 8,192931 95.3057 Toials: 635674.1 14.59307 11988.9 20455.19 347135 184096.5 11631.58 60366.87 597193.3 13.70967 39.48385 SITE2 2.919236 98 1.0559 61 Engcalc1-E-1 Bonuccelli Development Marielta & Sullivan 16•May-00 Stormwater Disposal SESwale Basin Areas: TOTAL Landscape Parking Total Imperoious Rational 3.975136 88.17183 Tolal Area• ACRES Area Landscape building paved loading unused' sf, acres 10-year Sites 6,7,8 (112) 1 38494.31 0.883708 8705 2067.476 15202.65 18607,49 846 900.1899 35466.32 0.814195 2.34488 3.441717 98 2 134662.6 3.091429 2549 3284,162 80494.24 29557,45 2102.418 16675,36 127161.9 2.919236 8.407401 0.267047 61 Toials: 173156.9 3.975136 3419.5 5351.638 95696.89 48164.95 2948.418 17575.55 162628.2 3,733431 10.75228 3.708724 95.33621 SITE5 Roadway Basin Area: Total Area, ACRES Area Landscape building paved laadmg unused* sf. acres 10-year ROADWAY 37708 0.865657 0 0 0 37708 0 0 37708 0.865657 2.493091 SS MH 1 SS MH 2 SS MH3 2.052474 98 Drain No. 1.: Drain No. 2.: Drain No. 3: 0.1026 61 2.155073 96.23849 0.7821067 acres Site 9 2.075201 acres upstream (Orain No.1) 7.59633 acres upstream (Drain No. 2) 0.3708219 acres Site 8 3.441717 acres Sites 6, 7, 8 2.331807 acres Site 3 0.9222727 acres Site 1 2.079412 acres Site 2 2.052474 acres Sde 5 20752013 total imperv. 7.59633 iotal imperv. 11,98061 tofal imperv. 6.2668989 Rational Flow, cfs 22.64108 Rational Flow, cfs 35.54261 Rational Flow, cfs 2.3020131 total area 8.192931 iotal area 12,7919 total area na TR55 FLOW, cis 5,182 TR55 FLOW, cfs 6.77 TR55 FLOW, cfs Required Pipe: Required Pipe: Required Pipe: 1.2208469 cfs 8.9634 cfs 7.339686 cfs 12 inches 18 inches 18 inches 0,035 slope 0.006204 slope 0.00416 slope 0.012 =n 0 012 =n 0.012 =n Inlets ta MH 1(S) Orain No. 4: 0.9222727 acres Site 1 0 additional 0.9222727 total imperv, 2.7873922 Rational Flow, cfs 1.0248092 total area na TR55 FLOW, cfs ' Required Pipe: 8.6305628 cfs 12 inches 0.05 slope 0.012 =n Inlets fa MH 1(N) Intets ta MH 2(S) Inlets 1o MH 2(N) Drain No. 7.: Drain No. S.: Drain No.9.: 1.1529286 acres Siles 9,8 0 acres upstream 0 acres upstream Engcalcl-E-2 . Bonuccelli Revelopment Marietfa & 5u11ivan 16-May-00 Sformwaler Dispqsal 0 addikiona! 2,919236 acres 5ite 2 3 441717 acres Sites 6,7,8 1.9529285 tofal imperv. 2,999236 tqial imperu 3,441717 fotal imperv, 3.4795067 Rafional Flow, cfa 9,75$953 Rafional Flow, ef5 14.25391 Ftation2l Flow, cfs 1.2772039 total area 3.915936 tvtal area, site 2 3,708724 tatal area, sitas 8,7,8 na 7R55 FLOW, cfs 2.475 TR55 FLOW, cfs 2,917 TR55 FLpW, cfs Required Pipe: Required Pipe. Required Pipe: 3.859705 cfs 8815788 Cfs 10.17839 C#s 12 inches 12 inches 1$ inches 0,41 slope 0,052174 slape 0.008 slape 0.012 =n 0.012 =n 0.012 =n Curb mk'et STA 0+43(N) Curb inlet 5TA 0+45(S) Inlets to MH 3(PI) Drain Na. 10: Orain No 51.: Dr2in No.12,: Q 1293159 2cres Ro2dway 0,129316 acres Roadway 0 acres upsfream Q addifianal Q additipnal 2,052474 acres Site 6 0.1293159 tatal impQrv. Q 129316 total imperv, 2 052474 tofal imperv. 4.372429$ Rational Flow, cfs 0,37243 Rationa! Ffow, cfa 6,042452 Rational Flow, cfs 0.9293159 total area 0 129376 total area 2155073 tofal area, sike 5 na 7R55 FLOW, cfs na TR55 FLOW, cis 9.706 7R55 FLOW, cfs Required Pipe: 7,366522 cfs 18 inches 0.00419 SCope 0.012 =n Grass Ghannnel def. 9114 fo inlet toMH1 Grass Channnel def 10141o inlef toMH1 Grass Channnel det 7/4 la Inlel 1aMFi2 Crain No. 13: Orain N4, 94; Drain No. 15: 1.1529286 acres Sifes 9,8 0.922273 acres Site1 3441717 acre5 Sites 87,8 p additional 0 additional 0 additional 7,1529286 tatal imperv, 0.922273 total impenr 1441717 total imperv. 3,4795067 Rational Flow, cis 2.7$7392 Rafional Flaw, cfs 10.25391 Rational Flow, cfs 1.2772439 tolal area 1.024849 total area 3708724 to#al area na TR55 FLOW, cfs na TR55 FL{7W, ef5 2 917 TR55 FLQW, cfS Required Ghannel: 30°lo FREE Required Channei, 30°lo FREE Required Channel: 30°la FREEBOARD: 5.7890535 efs 8.894291 4.946369 cfs 5.515433 10.99912 cfs 9-652008 95 inches battam width Llse- 12 incbes bottam width Use, 21 inches bottam width Use; 5.3033009 inches depth 1 4.242649 inches depth 05 7.424621 inches depth 1 O.005 slope 0A12 slopa 0,003 slvpe 0.025 =n 0.025 =n 0,025 -n 4.6533664 -v 5.824621 -v 6,996537 =v Grass Channnel def. 814 to inlet tvMFi2 Grass Channnel det 414&514 fo in€et toMH3 Grass Channnel det 614 fp inlei 1oS end SUVSw21e drain No. 18; Drain No. 17: Drain No. 1$- 2.9152363 acres Sile 2 2.052474 acres Sife 5 Q 554915 acre Site 3 Engcalc1-E-3 Bonuccelli Develapmenl Marietta 8 Sullivan 16-May-00 Slormwaler Disposal 0 additional 0 additional 0 addilianal 2.9192363 total imperv. 2.052474 iotal imperv. 0.554915 total imperv. 9.7589526 Ralional Flow, cfs 6.042452 Rational Flow, cfs 1.632297 Raiional Flow, cfs 3.9751364 total area 2.155073 total area 0.581589 total area 2.475 TR55 FLOW, cfs 1.106 TR55 FLOW, cfs na TR55 FLOW, cfs Required Channel: 30% FREE Required Channel: 30% FREE Required Channel: 30% FREEBOARD: 12.280437 cfs 6.894291 6.281895 cfs 5.515433 6.995222 cfs 5.515433 15 inches bottom width Use. 12 inches bottom width Use: 12 inches bottom width Use: 5.3433009 inches depth 1 4.242641 inches deplh 0,5 4.242641 inches depth 0.5 0.0225 slape 0.019355 slope 0.024 slope 0.025 =n 0,025 =n 0.025 =n 3.3099755 =v 3.56491 =v 3.410898 =v Grass Channnel of area 4 to inlet to Swale Pipe from Site 4 to SWSwale Drain No, 19: Orain No. 20: 1.7290599 acres Site 4 1.72906 acres Sile 4 0 addiGonal 0 additional 1.7290599 loial imperv. 1.72906 total imperv. 5.0719945 Rational Flow, cfs 5.071994 RaUonal Flow, cfs 1.8011708 total area 1.801171 total area na TR55 FLOW, cfs na TR55 FIOW, cfs Required Channel: 30% FREE Required Pipe; 8.7273266 cfs 6.894291 5 05354 cis 15 inches batfom width Use: 12 inches 5.3433009 inches depth 1 0.017143 slape 0.0113636 slope 0.012 =n 0.025 =n 6.783102 =v Complete TR55 SWDRAINAGE: 9.66 TR55 FLOW, cfs MAXIMUM DEPTH: 1.1 FEE7 SWSWALE DESIGN: BOTTOM AREA: 47801.7 cum. depth area storage Cum. slor. Gallons storagelaf 0 47801.7 0 0 0 0 0,5 48786,19 24146.97 24146.97 180643.5 0,554338 1 49770.67 24639.21 48786.19 364969.4 1.119977 1.5 50755.16 25131.46 73917.64 552977.9 1.696916 2 51739.64 25623.7 99541,34 744668,8 2.285155 Grass Channnel det 1214 to inlet to SESwale Orain No. 21: Engcalcl-E-4 Bonuccelli Development Marietta & Sullivan 16-May-00 Stormwater Disposal 3.7334308 acres Sifes 1,2 0 addilional 3.7334308 tolal imperv. 11.061664 Rational Flotiv, cfs 3.9751364 total area 3.94 TR55 FLOW, cfs Required Channel: 30% FREEBOARD: 5.7890535 cfs 6.894291 inches 15 inches bottom width Use, 5.3033069 inches depth 0.58 fooi 0.005 slope 0.025 =n 5.2692135 =v SESWALE DESIGN: BOTTOM AREA: 7608 cum. depth area acres storage Cum, stor. Gallons storagelaf 0 7608 0.174656 0 0 0 0 0.5 8181 0.18781 3947.25 3947 25 29529 38 0.090616 1 8754 0.200964 4233.75 8181 61202.06 0.18781 1.5 9327 0.214118 4520.25 12701.25 95018.05 0.291581 2 9900 0.227273 4806.75 17508 130977.3 0.401928 MAXIMUM DEPTH: 1.28 FEET ROADWAY SWALE DESIGN: BOTTOM AREA: 3409.336 cum. depth area acres storage Cum. s1or. Gallons sforagelaf 0 3409.336 0.078268 0 0 0 0 0.25 5795.872 0.133055 1150.651 1150.651 8608 02 0.026415 0.5 8182.407 0,187842 1747.285 2897.936 21679 46 0.066527 MAXIMUM DEPTH: 0.65 FEET (w!4 dr)Awells) Inlet Calculations: Catch Basin Inlet CalculaUons Catch Basin Inlet Capacity: (worst case, inlel taking entire flow) Inlet Depression, Type 1 Catth Basin: 01 ft. Flow: 0.37243 cfs = Q maximum allowable ponding: 0.16666 feet = h: maximum widlh of gutter Flow = 8,33 (eef each side; 20' fravel = head for weir of inlet grate widlh is lefi Required area of 1" wide slotted inlets: Cw= 3 Engcalc1-E-5 . 8oriuCCelEi G2veldpment Marieffa & Sullivan 16-May-DQ , 5t4fmwaf0f DiSpoSal Q=Cw'Lh"{3J2} L=Q1(Cw"h"(3J2)) L= 1.824635 feet Therefore a 23° by 99" grated inlet with 1" wide slofs and a grated perimeter lvier (3sides) of 61 inches = 5-9" will be adequafe. Worsl Case fnlet Depression, Type 1 Inlet: O.t ft, , Flow: 2.917 cfs = Q (use TR55 flQw calc where applir,able) maximLim aflpwable ponding; 0.4 feet = h ~ head for weir pf in€et grale Required area 4f 1" wide 51otted inlets: Cw= 3 Q=Cw"Lh"(3I2) L=QJ(Cw*h^(3!2)) L= 3.843485 feef 7herefore a 23" by 19" grated inlet wtth 1" wide slots and a graletl fotal perimeler wier (4sides) of 84 inches = 7'-0" will be adequate. Pipe'Inlet frpm N(o MH1, 12° Oie, HpPE N-12. Plow: 3,479507 cis = Q (u5e TR55 flow calc where applicable) calcufated depth: 5.303301 inches = 0,441942 {eet Depth available at inlet; 0 6G6667 feet Treat as inlet weir w! 6.441942 feef head Use weighted valus betvueen low 2nd high head weir formulas: Cw= 3 Q=Cw*Lh"(312) L=Cll(G1w"h1(312)) L= 3.947743 feet Cw= 0.67 Q-Cw'A*sqr1(2gH) A=Q!{Cuv"sqrt(3gH)} A- 0 973458 square feet A prpvided 1,10'5417 square feet Perimeter. 4,695 feet OK Pipe Inlef from N tv MH3, 18" Qia. HDPE N-12: Flow: 6.042452 cfs = Q (use 7R55 flaw calc where applicable) calculated depth; 4242641 incheS = 0,353553 feet Repih available at inlet; 1,5 feei Treat as inlet weir w! 0.353553 feet head Use wei9 hted value between low and higli head weir fflrmulasEngcalcl-E-6 Bonuccelli Development Marietta & Sullivan 16-May-00 Sformwater Disposal Cw= 3 Q=Cw"Lh^(3/2) L=Q/(Cw'h^(312)) L= 9.580969 feet Cw= 0.67 Q=Cw`A"sqrt(29H) A=QI(Cw'sqrt(2gH)) A= 1.890027 squarefeel A provided 3.044063 square feet Perimeter: 9.55125 feet OK Pipe Inlet from N to CulveR to SWSwaleMH3,12" Dia. HDPE N•12: Flow: 5.071994 cfs = Q (use TR55 flow calc where applicable) 16.14466 fps calculated depth: 7.5 inches = 0.625 feet Deplh available al inlet: 1 feet Treat as inlet weir w! 0.625 feet head Use weighted value between low and high head weir formulas: Cw= 3 Q=Cw'Lh^(3/2) L=QI(Cw"h^(312)) L= 3.421665 feet Cw= 0.67 Q=Cw"A*sqrt(2gH) A=Q!(Cw'sQrt(29H)) A= 1,193221 square feet A provided 1 105417 square feet Perimeter 4,695 feet OK Outfall Protection Calculations Outfalls to SWSwale For 18" Storm sewer ouifall, Vavg = 3.831036 fps This ouffall does not drop, B= 1.25 Therefore Vss = B`Vavg = 4.788795 fps Since the slope is level, Using Figure 34 from ihe Spokane County Guidelines for Stormwater Management: Mean stone size: 0115 feel, = 2,1 inches;say 3 inches (embedded stone) Riprap area dimensions: Worst case is unsubmerged discharge; use Figure 46 from Spokane County Gwdelines for Siormwater Man. La =1.80IDo^(3I2) +7Do (TW < Dol2) = 17.13322 feet, say 17 feet W = 3Do + 0.4La = 11.35329 feet, say 11 feet Engcalc1-E-7 . . n ~ Sonuccelli Develapment Nlarietta & Sullivan 16-May-00 $f4PfilWafQf d15p052l ror 12" fram Culvert under gravel driveway to west af cul-de-sac: v8vg = $.457$64 This outfall does drap, B= 1.5 Therefore Vss - B*Vavg = 9.6$6796 fps The slope is 3;1, UsiRg Figure 34 from t h e Sppkane Counfy Guideline5 for Stormwater Management: Mean 5tone size: 0,9 feek, _ 10,8 inches;say 11 (empedded 5tone) US0 rpund0d St4n2 Riprap area dimensipns; Warst case is unsubmerged discharge, use Figure 46 fro m Spoka ne Cqunly Guidelines far Sfarmwafer N1an. La = 1.8QlDa11(312) +PDa (TW > Qo12) - 16.12959 feet, say 16 fee# W=3do+0.4La = 9,451836 feet, say 9 feet SE Swa1e For 12" Gtass Channel from norlh and siEes 1 and 2: Vavg = 5.269214 This outfall daes nat drap, B= 1,25 Therefore Vss = B'Vavg = 6.586517 fps The slope is 3:1, Using Figure 34 from the Spakane Caunty Guidefines fpr 8kormwater Management: Mean stone size: 4.33 feet, = 3.96 inches;say 4 (embedded stone) Riprep area dimensions: Worst case is unsubmerged discharge, use Figure 46 from 5pokane Counky Guidelines far Skormwater Man. La =1.8QlDa"(312) +7Do (7W > Qo12} . = 15,06608 feet, s2y 15 feet IN = 3Do + 0.4La = 9 77643 feet, say 19 feet Engcale1-E-8 . TR-55 WORKSHEET 3 Time of Concenfiration or Travel Time Project : Bonuccelli Mari etta&Sullivan IBy : AEG Date : 2-11-98 Location: Watershed draining to SW swaleChecked: Date : Circle One: Present Developed Circle One: Tc Tt through subarea Notcs: Space for as many as two segments per flow type can be used for each worksheet. Inlcude a map, schematic, or description of flow scgments. SHEET FLOW (Applicable to Tc only) Segment ID Parcel 11 1. Surface Description (table 3-1) asphalt 2. Manning's roughncss coeff.,n (table 3-1)...... .02 0. 3. Flow Length, L(total L<= 300 ft) ft 200 4. 'ren-yr 24-hr rainfall, P2 in 2.12 0. 5. Land slope,s ...............................ft/ft 0.009 0. 6. Tt = 0.007(nL)^.8/P2^.5 s^.4 Computc Tt.... hr 0.0959 0. 0.0959 SHALLOW CONCENTRATED FLOW Seginent ID NEchannel 7. Surface Description (paved or unpaved) grass 8. Flow Lcngth, L ft 332 9. Watercoursc Slopc, s ........................ftlft 0.01 0. 10. Average Velocity, v(from figure) ............ft/s 1.5 0. 11. Tt = L(3600V) Compute Tt.... hr 0.0615 0. 0.0615 CHANNEL FLOW Seg7nent ID NCpipe CDSpipe 12. Cross Sectional Flow Area, .................ft^2 0.8 0.8 13. Wetted Perimeter, Pw ft 3.1 3.1 14. Hydraulic Radius r= a/Pw ft .3 .3 15. Channel Slope, s ............................ft/ft 0.02 0.004 16. Manning's roughness coeff.,n .015 0.015 17. V=1.49 r^2/3 s^1 /2 / n Compute V..........ft/s 5.57 2.49 18. Flow Length, L ft 472 122 19. Tt = L(3600V) Compute Tt.... llr 0.0235 0.0136 0.0371 20. Watershed or subarea Tc or Tt add Tc in steps 6,11, and 19 hr 0.195 c:\clientslbonuceli1tr55sw2.txt ' SAiADR 6.0 for 67indows watershed InEormation F7atershed Tota]. Azea (acres) :16.3090 Impervious Area (acres) :13.7100 Time of Concentration (min) :11.7 % Impervious Directly Connected :100.00 Additional Abstraction Over Pervious Area (inches) :0.10 Over Impervious Area (inches) :0.01 Infiltration Characteristics: P9ax Infiltration Capacity (a.n) :999.00 SCS Curve Number foz Pervious :61 Initial Abstraction Eactor :0.20 e:\clients\bonuceli\scaswale2.shd I r ~ Watershec'- Hydrograph FlOW 6 - - (cfs) , 4 ~ ~ 0 o - ~ l 'o 1 15 2'0 ~ 3'0 Time (hours) ' t[ydrCgraph Type :SCS 100 Hydrograph Time Time Rain C Rain Infiltration Er.cess Er.cess Outtlow (hr) HHMM (in) (in) (in) (in) (cfs) (cfs) 0.250 00015 0.009 0.004 0.000 0.000 0.000 0.000 0.500 00030 0.006 0.010 0.000 0.000 0.028 0.005 0.750 00095 0.006 0.017 0.000 0.005 0.398 0.072 1.000 00100 0.006 0.023 0.000 0.005 0.398 0.132 1.250 00115 0.006 0.029 0.000 0.005 0.348 0.189 1.500 00130 0.006 0.036 0.000 0.005 0.348 0.230 1.750 00145 0.006 0.042 0.000 0.005 0.346 0.267 2.000 00200 0.006 0.048 0.000 0.005 0.348 0.298 2.250 00215 0.006 0.055 0.000 0.005 0.348 0.321 2.500 00230 0.006 0.061 0.000 0.005 0.348 0.338 2.750 00295 0.006 0.067 0.000 0.005 0.348 0.346 3.000 00300 0.006 0.073 0.000 0.005 0.348 0.398 3.250 00315 0.006 0.080 0.000 0.005 0.348 0.348 3.500 00330 0.006 0.086 0.000 0.005 0.348 0.348 3.750 00345 0.006 0.092 0.000 0.005 0.398 0.348 4.000 00900 0.008 0.101 0.000 0.007 0.964 0.371 9.250 00915 0.008 0.109 0.001 0.007 0.964 0.391 9.500 00930 0.008 0.116 0.001 0.007 0.464 0.409 9.750 00445 0.008 0.126 0.001 0.007 0.464 0.424 5.000 00500 0.008 0.134 0.001 0.007 0.464 0.437 5.250 00515 0.008 0.143 0.001 0.007 0.464 0.497 5.500 00530 0.008 0.151 0.001 0.007 0.464 0.455 5.750 00545 0.008 0.160 0.001 0.007 0.969 0.961 6.000 00600 0.006 0.169 0.001 0.007 0.469 0.964 6.250 00615 0.011 0.178 0.002 0.009 0.580 0.987 6.500 00630 0.011 0.189 0.002 0.009 0.580 0.507 6.750 00695 0.010 0.199 0.002 0.009 0.560 0.525 7.000 00700 0.011 0.210 0.002 0.009 0.560 0.540 7.250 00715 0.010 0.220 0.002 0.009 0.580 0.553 7.500 00730 0.011 0.231 0.002 0.009 0.580 0.563 7.750 00795 0.011 0.291 0.002 0.009 0.580 0.571 8.000 00800 0.010 0.252 0.002 0.009 0.580 0.577 8.250 00815 0.013 0.265 0.002 0.011 0.697 0.602 8.500 00830 0.015 0.279 0.002 0.012 0.813 0.646 8.750 00895 0.015 0.299 0.002 0.012 0.813 0.683 9.000 00900 0.015 0.309 0.002 0.012 0.813 0.716 9.250 00915 0.017 0.325 0.003 0.019 0.929 0.767 9.500 00930 0.017 0.342 0.003 0.014 0.929 0.810 9.750 00945 0.019 0.361 0.003 0.016 1.045 0.869 10.00 01000 0.019 0.380 0.003 0.016 1.045 0.918 10.25 01015 0.021 0.401 0.003 0.018 1.161 0.979 10.50 01030 0.025 0.426 0.009 0.021 1.393 1.074 10.75 01045 0.032 0.458 0.005 0.026 1.791 1.221 11.00 01100 0.038 0.996 0.006 0.032 2.090 1.415 11.25 01115 0.044 0.540 0.007 0.037 2.438 1.650 11.50 01130 0.055 0.594 0.009 0.046 3.018 1.964 11.75 01145 0.218 0.823 0.035 0.184 12.073 3.990 12.00 01200 0.580 1.392 0.092 0.487 32.040 9.655 12.25 01215 0.092 1.985 0.019 0.078 5.126 9.453 12.50 01230 0.059 1.543 0.009 0.050 3.276 8.807 12.75 01245 0.048 1.592 0.007 0.041 2.699 8.009 13.00 01300 0.038 1.630 0.006 0.032 2.117 7.060 13.25 01315 0.031 1.661 0.005 0.027 1.767 6.037 13.50 01330 0.027 1.688 0.004 0.023 1.539 9.974 13.75 01395 0.023 1.711 0.003 0.020 1.300 3.883 14.00 01900 0.021 1.732 0.003 0.018 1.183 2.801 19.25 01915 0.019 1.751 0.003 0.016 1.065 1.869 14.50 01930 0.017 1.768 0.002 0.019 0.948 1.940 14.75 01445 0.015 1.783 0.002 0.013 0.830 1.238 15.00 01500 0.015 1.798 0.002 0.013 0.831 1.099 15.25 01515 0.015 1.812 0.002 0.013 0.831 1.002 15.50 01530 0.013 1.825 0.002 0.011 0.713 0.913 15.75 01595 0.013 1.837 0.002 0.011 0.713 0.848 16.00 01600 0.013 1.850 0.002 0.011 0.719 0.801 16.25 01615 0.013 1.863 0.002 0.011 0.714 0.769 16.50 01630 0.013 1.875 0.002 0.011 0.715 0.746 16.75 01645 0.010 1.866 0.001 0.009 0.596 0.709 17.00 01700 0.010 1.896 0.001 0.009 0.596 0.680 17.25 01715 0.010 1.907 0.001 0.009 0.596 0.657 17.50 01730 0.010 1.917 0.001 0.009 0.597 0.638 17.75 01745 0.010 1.928 0.001 0.009 0.597 0.625 18.00 01800 0.008 1.936 0.001 0.007 0.978 0.591 18.25 01815 0.008 1.945 0.001 0.007 0.978 0.563 18.50 01830 0.008 1.953 0.001 0.007 0.978 0.539 18.75 01895 0.008 1.961 0.001 0.007 0.978 0.520 19.00 01900 0.008 1.970 0.001 0.007 0.979 0.507 19.25 01915 0.008 1.978 0.001 0.007 0.479 0.496 19.50 01930 0.008 1.987 0.001 0.007 0.479 0.488 19.75 01995 0.008 1.995 0.001 0.007 0.979 0.982 20.00 02000 0.006 2.001 0.001 0.005 0.359 0.456 20.25 02015 0.006 2.008 0.001 0.005 0.359 0.935 20•.50 02,030 0.006 2.014 0.001 0.005 0.360 0.917 20.75 02045 0.006 2.020 0.001 0.005 0.360 0.401 21.00 02100 0.006 2.026 0.001 0.005 0.360 0.388 21.25 02115 0.006 2.033 0.001 0.005 0.360 0.378 21.50 02130 0.006 2.039 0.001 0.005 0.360 0.369 21.75 02145 0.006 2.095 0.001 0.005 0.360 0.364 22.00 02200 0.006 2.052 0.001 0.005 0.360 0.361 22.25 02215 0.006 2.056 0.001 0.005 0.360 0.360 22.50 02234 0.006 2.069 0.001 0.005 0.360 0.360 22.75 02295 0.006 2.071 0.001 0.005 0.360 0.360 23.00 02300 0.006 2.077 0.001 0.005 0.361 0.360 23.25 02315 0.006 2.083 0.001 0.005 0.361 0.360 23.50 02330 0.006 2.089 0.001 0.005 0.361 0.360 23.75 02345 0.006 2.096 0.001 0.005 0.361 0.361 29.00 00000 0.004 2.100 0.001 0.009 0.241 0.337 24.25 00015 0.000 2.100 0.000 0.000 0.000 0.270 24.50 00030 0.000 2.100 0.000 0.000 0.000 0.210 24.75 00045 0.000 2.100 0.000 0.000 0.000 0.158 25.00 00100 0.000 2.100 0.000 0.000 0.000 0.713 25.25 00115 0.000 2.100 0.000 0.000 0.000 0.075 25.50 00130 0.000 2.100 0.000 0.000 0.000 0.096 2.100 0.307 1.768 1.767 Totals for 6•7atershed in inches over 16.31 acres Rational Coef£zcient = 0.859 Peak FlOw (cfs) = 09.66 e:\clients\bonuceli\swswale2.hyd Stage 'Storage Weir 1 Q 4deir 2 Q Discharge (tt) (ac-ft) (cfs) (cfs) (cfs) 0.00 0.00 0.00 0.00 0.00 0.50 0.55 0.00 0.00 0.00 1.00 1.12 0.66 0.66 1.33 1.50 1.70 3.75 3.75 7.50 2.00 2.29 10.33 10.33 20.67 Weir Numberl Type : Circular Orifice Equation : Q = C*A*2g^.5*H^n 6Jeir Invert (ft) . 0.50 C: 0.60 n: 0.50 Orifice Diameter (ft) . 1.50 Weir Number2 Type : Circular Orifice Equation : Q = C*A*2g^.5*H^n weir Invert (ft) . 0.50 C: 0.60 n: 0.50 Orifice Diameter (ft) . 1.50 e:\cli.ents\bonuceli\swswale2.pnd outln~ . R- p on ,o - ~ ~ ~ ~and ~low In . ~ ° / $ ~ - ~ ~ , 6 ~ ~ _ _ , . F1Q~ ~ ~ - - - - ~ oU~ C~S 1 ` J~ ' P°n~ Flp~ ~ ~ ~ ~ ~ r- - 2 ~ ~ ~ 3~ ~ ~ . . ~ - - - ~Q 2 ~ , 15 o , h~ur } 0~''~~ 5 S T lYne Time ` Inflow Outflow Stage Storage (hr) (cfs) (cfs) ' (ft) (ac-tt) 0.25 0.00 0.00 0.00 0.00 0.50 0.01 0.00 0.00 0.00 0.75 0.07 0.00 0.00 0.00 1.00 0.13 0.00 0.00 0.00 1.25 0.1.8 0.00 0.00 0.00 1.50 0.23 0.00 0.00 0.00 1.75 0.27 0.00 0.00 0.00 2.00 0.30 0.00 0.00 0.00 2.25 0.32 0.00 0.00 0.00 2.50 0.34 0.00 0.00 0.00 2.75 0.35 0.00 0.00 0.00 3.00 0.35 0.00 0.00 0.00 3.25 0.35 0.00 0.00 0.00 3.50 0.35 0.00 0.00 0.00 3.75 0.35 0.00 0.00 0.00 4.00 0.37 0.00 0.00 0.00 4.25 0.39 0.00 0.00 0.00 4.50 0.41 0.00 0.00 0.00 4.75 0.42 0.00 0.00 0.00 5.00 0.49 0.00 0.00 0.00 5.25 0.45 0.00 0.00 0.00 5.50 0.95 0.00 0.00 0.00 5.75 0.96 0.00 0.00 0.01 6.00 0.46 0.00 0.01 0.01 6.25 0.99 0.00 0.01 0.01 6.50 0.51 0.00 0.01 0.01 6.75 0.52 0.00 0.01 0.01 7.00 0.54 0.00 0.01 0.02 7.25 0.55 0.00 0.02 0.02 7.50 0.56 0.00 0.02 0.02 7.75 0.57 0.00 0.02 0.03 8.00 0.58 0.00 0.03 0.03 8.25 0.60 0.00 0.03 0.03 8.50 0.65 0.00 0.04 0.04 8.75 0.68 0.00 0.04 0.04 9.00 0.72 0.00 0.05 0.05 9.25 0.77 0.00 0.05 0.06 9.50 0.81 0.00 0.06 0.07 9.75 0.87 0.00 0.07 0.08 10.00 0.92 0.00 0.08 0.09 10.25 0.98 0.00 0.09 0.10 10.50 1.07 0.00 0.10 0.11 10.75 1.22 0.00 0.12 0.13 11.00 1.92 0.00 0.14 0.15 11.25 1.65 0.00 0.16 0.18 11.50 1.96 0.00 0.19 0.21 11.75 3.99 0.00 0.25 0.28 12.00 9.66 0.00 0.41 0.46 12.25 9.95 0.21 0.58 0.64 12.50 8.E1 0.60 0.73 0.81 12.75 8.00 0.93 0.85 0.95 13.00 7.06 1.21 0.96 1.07 13.25 6.04 1.75 1.03 1.16 13.50 4.97 2.34 1.08 1.21 13.75 3.88 2.58 1.10 1.24 19.00 2.80 2.56 1.10 1.24 14.25 1.87 2.36 1.08 1.22 14.50 1.94 2.10 1.06 1.19 19.75 1.29 1.85 1.09 1.17 15.00 1.10 1.62 1.02 1.15 15.25 1.00 1.41 1.01 1.13 15.50 0.91 1.30 0.99 1.11 15.75 0.85 1.26 0.93 1.09 16.00 0.80 1.22 0.96 1.08 16.25 0.77 1.18 0.95 1.06 16.50 0.75 1.14 0.93 1.09 16.75 0.71 1.10 0.92 1.02 17.00 0.68 1.06 0.90 1.01 17.25 0.66 1.02 0.89 0.99 17.50 0.64 0.99 0.87 0.97 17.75 0.62 0.95 0.86 0.96 18.00 0.59 0.91 0.84 0.94 18.25 0.56 0.88 0.83 0.93 18.50 0.54 0.84 0.82 0.91 18.75 0.52 0.81 0.80 0.90 19.00 0.51 0.77 0.79 0.88 19.25 0.50 0.74 0.78 0.87 19.50 0.99 0.71 0.77 0.86 19.75 0.98 0.68 0.76 0.84 20.00 0.96 0.65 0.74 0.83 20.25 0.93 0.62 0.73 0.82 20.50 0.92 0.59 0.72 0.81 20.75 0.90 0.56 0.71 0.79 ~1.00 ' 0.39 0.53 0.70 0.78 21.25 0.38 0.51 0.69 0.77 21.50 0.37 0.96 0.68 0.76 21.75 0.36 0.96 0.67 0.75 22.00 0.36 0.43 0.66 0.79 22.25 0.36 0.91 0.65 0.73 22.50 0.36 0.39 0.65 0.72 22.75 0.36 0.37 0.64 0.71 23.00 0.36 0.35 0.63 0.70 23.25 0.36 0.33 0.62 0.69 23.50 0.36 0.31 0.62 0.69 23.75 0.36 0.29 0.61 0.68 24.00 0.39 0.28 0.60 0.67 24.25 0.27 0.26 0.60 0.66 29.50 0.21 0.24 0.59 0.65 24.75 0.16 0.21 0.58 0.65 25.00 0.11 0.19 0.57 0.69 25.25 0.08 0.17 0.56 0.62 25.50 0.05 0.14 0.55 0.61 25.75 0.00 0.11 0.54 0.60 26.00 0.00 0.09 0.53 0.59 26.25 0.00 0.07 0.53 0.58 26.50 0.00 0.04 0.52 0.57 26.75 0.00 0.02 0.51 0.56 Max: 9.66 2.58 1.10 1.24 Initial Pond volume . 000.000 ac-ft + Total Intlow Volume . 002.902 ac-ft Total Outfloca Volume . 000.995 ac-ft Total Percolation Volume : 000.846 ac-ft Final Pond Volume (stage): 000.564 ac-ft Einal Pond Volume (calc) : 000.560 ac-ft Difference (error) . 000.003 ac-ft e:\clients\bonuceli\swswale2.rte TR-55 WORKSHEET 3 Time of Concentration or Travel Time Pi-oject : Bonuccelli Marietta & SullivanBy : AEG Date : 2-11-98 Location: SESwale watcrshed Checked: Date : Circle One: Present Developed Circle One: Tc Tt through subarea Notes: Space for as many 1s two segments pcr flow type can be used for each worksheet. Inlcudc a map, schematic, or description of flow segments. SHEET FLOW (Applicable to Tc only) Segment ID I'arcel 9 1. Surf.ace Description (table 3-1) asphalt 2. Manning's roug}uless coeff.,n (fiable 3-1)...... .02 0. 3. Flow Length, L(total L<= 300 ft) ft 55 4. Ten-yr 24-hr rainfall, P2 in 2.12 0. 5. Land slope,s ...............................ftlf.t 0.0064 0. 6. Tt = 0.007(nL)^.8/P2^.5 s^.4 Compute Tt.... hr 0.0391 0. 0.0391 SHALLOW COrICENTRATED FLOW Scgment ID chane19 channe13 7. Surface Description (paved or unpaved) grass grass 8. Flow Length, L ft 55 141 9. Watercourse Slope, s ........................ftlft 0.01 0.018 10. AveragE Velocity, v(from figure) ............ft/s 0.75 1. 11. Tt = L(3600V) Compute Tt.... h.r 0.0204 0.0391 0.0595 CHANNEL FLOW SegYnent ID 12. Cross Sectional Flow Area. ft^2 0. 0. 13. Wetted Perimeter, Pw f.t . . 14. Hydraulic Radius r= a/Pw ft . . 15. Channel Slope, s ............................fuft 0. 0. 16. Manning's roughness coeff.,n . 0. 17. V=1.49 r^2/3 s^ 1/2 / n Compute V.......... ftls 0. 0. 18. Flow Length, L ft 19. Tt = L(3600V) Compute Tt.... hr 0. 0. 0. 20. Watershed or subarea Tc or Tt add Tc in steps 6,11, and 19 hr 0.099 c:\cl ients\bonuceli\tr55 se.txt ' SP'rAAA 6.0 for y7indows watershEd Information Watezshed Total Area (acres) :3.9700 Imperva.ous Area (acres) :3.4300 Time of Concentrata.on (min) :5.9 ° $ Impervious Direct].y Connected :100.00 Additional Abstraction Over Pervious Area (inches) :0.10 Over Impervious Area (i.nches) :0.01 Infiltration Characteristics: Max Tnfa.ltration Capacity (in) :999.00 SCS Curve Number foz Pervious :61 Initial Abstraction Factor :0.20 e:\clients\bonuceli\seswale.shd Watershed Hydrograp--'I 4 - ~ 3 Flow (CfS) 2 , - - 0 OJ~~~ 10 11 5 2'0 2~5 Time (hours) Hydrograph Type :SCS 100 Hydrograph Time Time Rain C•Rain Infiltration Excess Excess Outflow (hr) HHMM (in) (in) (in) (in) (cfs) (cfs) 0.250 00015 0.009 0.009 0.000 ' 0.000 0.000 0.000 0.500 00030 0.006 0.010 0.000 0.000 0.007 0.002 0.750 00045 0.006 0..017 0.000 0.005 0.087 0.033 1.000 00100 0.006 0.023 0.000 0.005 0.087 0.057 1.250 00115 0.006 0.029 0.000 0.005 0.087 0.074 1.500 00130 ' 0.006 0.036 0.000 0.005 0.087 0.085 1.750 00145 0.006 0.092 0.000 '0.005 0.087 0.089 2.000 00200 0.006 0.093 0.000 0.005 0.087 0.087 2.250 00215 0.006 0.055 0.000 0.005 0.087 0.087 2.500 00230 0.006 0.061 0.000 0.005 0.087 0.087 2.750 00245 0.006 0.067 ' 0.000 0.005 0.087 0.087 3.000 00300 0.006 0.073 0.000 0.005 0.087 0.087 3.250 00315 0.006 0.080 0.000 0.005 0.087 0.087 3.500 00330 0.006 0.086 0.000 0.005 0.087 0.087 3.750 00345 0.006 0.092 0.000 0.005 0.087 0.087 4.000 00900 0.008 0.101 0.000 • 0.007 0.116 0.097 4.250 00915 0.008 0.109 0.001 0.007 0.116 0.106 9.500 00430 0.008 0.118 0.001 0.007 0.116 0.111 4.750 00445 0.008 0.126 0.001 0.007 0.116 0.115 5.000 00500 0.008 0.134 0.001 0.007 0.116 0.117 5.250 00515 0.008 0.143 0.001 0.007 0.116 0.116 5.500 00530 0.008 0.151 0.001 0.007 0.116 0.116 5.750 00545 0.008 0.160 0.001 0.007 0.116 0.116 6.000 00600 0.008 0.168 0.001 0.007 0.116 0.116 6.250 00615 0.011 0.178 0.001 0.009 0.145 0.126 6.500 00630 0.011 0.189 0.001 0.009 0.145 0.135 ' 6.750 00645 0.010 0.199 0.001 0.009 0.145 0.141 7.000 00700 0.011 0.210 0.001 0.009 0.145 0.149 7.250 00715 0.010 0.220 0.001 0.009 0.145 0.146 7.500 00730 0.011 0.231 0.001 0.009 0.145 0.145 7.750 00745 0.011 0.241 0.001 0.009 0.145 0.195 8.000 00800 0.010 0.252 0.001 0.009 0.145 0.145 8.250 00815 0.013 0.265 0.002 0.011 0.174 0.156 8.500 00830 0.015 0.279 0.002 0.013 0.203 0.174 8.750 00845 0.015 0.299 0.002 0.013 0.203 0.188 9.000 00900 0.415 0.309 0.002 0.013 0.203 0.198 9.250 00915 0.017 0.325 0.002 0.015 0.232 0.213 9.500 00930 0.017 0.342 0.002 0.015 0.232 0.222 9.750 00945 0.019 0.361 0.003 0.016 0.261 0.238 10.00 01000 0.019 0.380 0.003 0.016 0.261 0.250 10.25 01015 0.021 0.901 0.003 0.018 0.290 0.268 10.50 01030 0.025 0.426 0.003 0.022 0.399 0.299 10.75 01095 0.032 0.458 0.009 0.027 0.436 0.354 11.00 01100 0.036 0.496 0.005 0.033 0.523 0.424 11.25 01115 0.044 0.540 0.006 0.038 0.610 0.506 11.50 01130 0.055 0.594 0.007 0.047 0.755 0.619 11.75 01145 0.218 0.813 0.030 0.189 3.020 1.490 12.00 01200 0.580 1.392 0.079 0.501 8.016 3.939 12.25 01215 0.092 1.985 0.012 0.080 1.282 3.931 12.50 01230 0.059 1.593 0.008 0.051 0.818 2.703 12.75 01245 0.048 1.592 0.006 0.092 0.674 1.911 13.00 01300 0.038 1.630 0.005 0.033 0.526 1.076 13.25 01315 0.031 1.661 0.004 0.028 0.441 0.445 13.50 01330 0.027 1.688 0.003 0.024 0.383 0.971 13.75 01395 0.023 1.711 0.003 0.020 0.324 0.399 14.00 01400 0.021 1.732 0.003 0.018 0.295 0.399 14.25 01415 0.019 1.751 0.002 0.017 0.266 0.305 14.50 01430 0.017 1.768 0.002 0.015 0.236 0.271 14.75 01445 0.015 1.783 0.002 0.013 0.207 0.291 15.00 01500 0.015 1.798 0.002 0.013 0.207 0.223 15.25 01515 0.015 1.812 0.002 0.013 0.207 0.212 15.50 01530 0.013 1.825 0.002 0.011 0.176 0.197 15.75 01545 0.013 1.837 0.001 0.011 0.178 0.168 16.00 01600 0.013 1.850 0.001 0.011 0.178 0.183 16.25 01615 0.013 1.863 0.001 0.011 0.178 0.179 16.50 01630 0.013 1.875 0.001 0.011 0.178 0.177 16.75 01695 0.010 1.886 0.001 0.009 0.198 0.167 17.00 01700 0.010 1.896 0.001 0.009 0.148 0.159 17.25 01715 0.010 1.907 0.001 0.009 0.199 0.153 17.50 01730 0.010 1.917 0.001 0.009 0.149 0.149 17.75 01745 0.010 1.928 0.001 0.009 0.149 0.148 18.00 01800 0.008 1.936 0.001 0.007 0.119 0.138 18.25 01815 0.008 1.945 0.001 0.007 0.119 0.130 18.50 01830 0.008 1.953 0.001 0.007 0.119 0.129 18.75 01845 0.006 1.961 0.001 0.007 0.119 0.120 19.00 01900 0.006 1.970 0.001 0.007 0.119 0.118 19.25 01915 0.008 1.978 0.001 0.007 0.119 0.119 19.50 01930 0.008 1.987 0.001 0.007 0.119 0.119 19.75 01945 0.008 1.995 0.001 0.007 0.119 0.119 20.00 02000 0.006 2.007. 0.001 0.006 0.089 0.109 20.25 02015 0.006 2.008 0.001 0.006 0.089 0.100 20~50 02030 0.006 2.019 0.001 0.006 0.089 0.099 20.75 02045 0.006 2.020 0.001 0.006 0.090 0.090 21.00 02100 0.006 2.026 0.001 0.006 0.090 0.089 21.25 02115 0.006 2.033 0.001 0.006 0.090 0.090 21.50 02130 0.006 2.039 0.001 0.006 0.090 0.090 21.75 02195 0.006 2.095 0.001 0.006 0.090 0.090 22.00 02200 0.006 2.052 0.001 0.006 0.090 0.090 22.25 02215 0.006 2.058 0.001 0.006 0.090 0.090 22.50 02230 0.006 2.069 0.001 0.006 0.090 0.090 22.75 02295 0.006 2.071 0.001 0.006 0.090 0.090 23.00 02300 0.006 2.077 0.001 0.006 0.090 0.090 23.25 02315 0.006 2.083 0.001 0.006 0.090 0.090 23.50 02330 0.006 2.089 0.001 0.006 0.090 0.090 23.75 02395 0.006 2.096 0.001 0.006 0.090 0.090 24.00 00000 0.009 2.100 0.000 0.009 0.060 0.079 24.25 00015 0.000 2.100 0.000 0.000 0.000 0.050 24.50 00030 0.000 2.100 0.000 0.000 0.000 0.027 24.75 OOOAS 0.000 2.100 0.000 0.000 0.000 0.011 2.100 0.262 1.815 1.815 Totals for watershed in inches over 3.97 acres Rational Coefficient = 0.875 Peak Flo4a (cfs) = 03.94 e:\clients\seswale.hyd Stege Storage tleir 1 Q weir 2 Q Discharge (ft) (ac-ft) (cfs) (cfs) (cfs) 0.00 0.00 0.00 0.00 0.00 0.50 0.09 0.00 0.00 0.00 1.00 0.19 0.33 0.33 0.66 1.50 0.29 1.68 1.68 3.37 Weir Numberl Type : Circular Orifice Equat-ion . Q = C+A*2g^.5*H^n Weir Invert (ft) . 0.50 C: 0.60 n: 0.50 Orifice Diameter (ft) . 0.75 4deir Number2 Type : Circular Ora.fice Equation : Q = C*A*2g^.5tH^n 4Jeir Invert (ft) . 0.50 C: 0.60 n: 0.50 Orifice Diameter (ft) . 0.75 e:\clients\bonuceli\seswale.pnd Pond Routing 4- 3--- - i, Pond Flow In Flow (CfS) 2---- -.~g ~ Pond Flow Out / ~ ~ i - f ~`i~ • \ , - - O ` I - Y 0 5 10 15 20 25 Time (hours) Time 'Inflow Outflow Stage Storage (hr) (cfs) (cfs) (ft) (ac-ft) 0.25 0.00 0.00 0.00 0.00 0.50 0.00 0.00 0.00 0.00 0.75 0.03 0.00 0.00 0.00 1.00 0.06 0.00 0.00 0.00 1.25 0.07 0.00 0.00 0.00 1.50 0.08 0.00 0.00 0.00 1.75 0.09 0.00 0.01 0.00 2.00 0.09 0.00 0.01 0.00 2.25 0.09 0.00 0.01 0.00 2.50 0.09 0.00 0.01 0.00 2.75 0.09 0.00 0.02 0.00 3.00 0.09 0.00 0.02 0.00 3.25 0.09 0.00 0.02 0.00 3.50 0.09 0.00 0.03 0.00 3.75 0.09 0.00 0.03 0.01 4.00 0.10 0.00 0.03 0.01 9.25 0.11 0.00 0.04 0.01 9.50 0.11 0.00 0.09 0.01 4.75 0.12 0.00 0.05 0.01 5.00 0.12 0.00 0.05 0.01 5.25 0.12 0.00 0.06 0.01 5.50 0.12 0.00 0.07 0.01 5.75 0.12 0.00 0.07 0.01 6.00 0.12 0.00 0.08 0.01 6.25 0.13 0.00 0.08 0.02 6.50 0.13 0.00 0.09 0.02 6.75 0.14 0.00 0.10 0.02 7.00 0.14 0.00 0.11 0.02 7.25 0.15 0.00 0.12 0.02 7.50 0.15 0.00 0.13 0.02 7.75 0.15 0.00 0.14 0.02 8.00 0.15 0.00 0.15 0.03 8.25 0.16 0.00 0.16 0.03 8.50 0.17 0.00 0.17 0.03 6.75 0.19 0.00 0.18 0.03 9.00 0.20 0.00 0.20 0.04 9.25 0.21 0.00 0.21 0.09 9.50 0.22 0.00 0.23 0.04 9.75 0.24 0.00 0.25 0.05 10.00 0.25 0.00 0.27 0.05 10.25 0.27 0.00 0.29 0.05 10.50 0.30 0.00 0.32 0.06 10.75 0.35 0.00 0.35 0.06 11.00 0.42 0.00 0.39 0.07 11.25 0.51 0.00 0.44 0.08 11.50 0.61 0.00 0.50 0.09 11.75 1.99 0.18 0.64 0.12 12.00 3.94 0.64 0.98 0.18 12.25 3.43 1.77 1.20 0.23 12.50 2.70 2.16 1.28 0.25 12.75 1.91 2.05 1.26 0.24 13.00 1.08 1.63 1.18 0.23 13.25 0.45 1.11 1.08 0.21 13.50 0.97 0.81 1.03 0.19 13.75 0.90 0.65 0.99 0.19 19.00 0.39 0.60 0.95 0.18 14.25 0.30 0.55 0.92 0.17 14.50 0.27 0.50 0.68 0.16 19.75 0.24 0.46 0.85 0.16 15.00 0.22 0.92 0.82 0.15 15.25 0.21 0.38 0.79 0.15 15.50 0.20 0.35 0.76 0.14 15.75 0.19 0.32 0.74 0.14 16.00 0.18 0.29 0.72 0.13 16.25 0.18 0.27 0.70 0.13 ' 16.50 0.18 0.25 0.69 0.13 16.75 0.17 0.23 0.67 0.12 17.00 0.16 0.21 0.66 0.12 17.25 0.15 0.19 0.65 0.12 17.50 0.15 0.18 0.63 0.12 17.75 0.15 0.16 0.62 0.12 18.00 0.14 0.15 0.62 0.11 18.25 0.13 0.14 0.51 0.11 18.50 0.12 0.13 0.60 0.11 18.75 0.12 0.12 0.59 0.11 19.00 0.12 0.11 0.58 0.11 19.25 0.12 0.10 0.58 0.11 19.50 0.12 0.10 0.57 0.10 19.75 0.12 0.09 0.57 0.10 20.00 0.11 0.08 0.56 0.10 20.25 0.10 0.08 0.56 0.10 20.50 0.09 0.07 0.55 0.10 20.75 0.09 0.06 0.55 0.10 21.00 ` 0.09 0.06 0.54 0.10 21.25 0.09 0.05 0.54 0.10 21.50 0.09 0.05 0.54 0.10 21.75 0.09 0.09 0.53 0.10 22.00 0.09 0.09 0.53 0.10 22.25 0.09 0.09 0.53 0.10 22.50 0.09 0.09 0.53 0.10 22.75 0.09 0.03 0.53 0.10 23.00 0.09 0.03 0.52 0.10 23.25 0.09 0.03 0.52 0.10 23.50 0.09 0.03 0.52 0.10 23.75 0.09 0.03 0.52 0.10 24.00 0.08 0.03 0.52 0.09 24.25 0.05 0.02 0.52 0.09 29.50 0.03 0.01 0.51 0.09 24.75 0.01 0.00 0.50 0.09 25.00 0.00 0.00 0.50 0.09 Max: 3.94 2.16 1.28 0.25 Initial Pond Volume . 000.000 ac-ft + Total Inflow Volume . 000.600 ac-ft Total Outflow Volume . 000.374 ac-ft Total Percolation Volume : 000.136 ac-ft Final Pond volume (stage): 000.090 ac-ft Final Pond Volume (calc) : 000.090 ac-ft Difference (error) . 000.000 ac-ft e:\clients\bonuceli\seswale.rte ' +TR-55 4JORKSHEET 3 Time of Concentration oz Travel Time Project : Bonuccelli's Marietta & SullivBy : AEG Date : 5-16-00 Location: West End, Marietta Checked: Date : Circle One: Present Developed Circle One: Tc Tt through subarea Notes: Space for as many as two segments per f.low type can be used for each worksheet. Inlcude a map, schematic, or description of floca segments. SHEET FLOv7 (Applicable to Tc only) Segment ID CuldeSac 1. Surface Description (table 3-1) asphalt 2. Manning's roughness coeff.,n (table 3-1)...... .02 0. 3. Flow Length, L(total L<= 300 ft) ft 134 4. Ten-yr 29-hr rainfall, P2 in 2.1 0. 5. Land slope s ...............................ft/ft 0.004 0. 6. Tt = 0.007(nL)^.8/P2^.5 s^.4 Compute Tt.... hr 0.0966 0. 0.0966 SHALLOW CONCENTRATED ELOW Segment ID 7. Surface Description (paved or unpaved) 8. Flota Length, L ft 9. Watercourse Slope, s ........................ft/ft 0. 0. 10. Average Velocity, v(from figure) ............ft/s 0. 0. 11. Tt = L(3600V) Compute Tt.... hr 0. 0. 0. CHANNEL FLOW Segment ID 12. Cross Sectional Flow Area, .................ft"2 0. 0. 13. Wetted Perimeter, Pw ft . . 14. Hydraulic Radius r= a/Pw ft . . 15. Channel Slope, s ............................ft/ft 0. 0. 16. Manning's roughness coeEf.,n . 0. 17. V=1.49 r^2/3 s^1/2 / n Compute V ft/s 0. 0. 18. Flow Length, L ft 19. Tt = L(3600V) Compute Tt.... hr 0. 0. 0. 20. Watershed or subarea Tc or Tt add Tc in steps 6,11, and 19 hr 0.097 e:\clients\bonucelli\wguttr55.txt ~ SMhDA 6.0 for Windows Watershed Information Watershed Total Area (acres) :0.3450 Zmpervious Area (acres) :0.2860 Time of Concentration (min) :5.8 b Impervious Directly Connected :100.00 Additional Abstraction Over Pervious Area (znches) :0.10 Over Impervious Area (inches) :0.01 Infiltration Characterisiics: Max Infiltration Capacity (in) :999.00 SCS Curve Number for Pervious :61 Initial Abstraction Factor :0.20 e:\clients\bonuceli\wroadway.shd . ; Waters--led Hydrograph 0.4 y 0.3 - - - - Flow (CfS) 0.2 - - - . - ~ : . 0.1 ~ 0.0 O~ 5 1~0 1'5 2'0 2f5 ~ Time (hours) ~ Hydrograph Type :SCS 100 Hydrograph Time Time Rain C Rain Infiltration Excess Excess Outflow (hr) HHMt9 (in) (in) (in) (in) (cfs) (cfs) 0.250 00015 0.009 0.009 0.000 0.000 0.000 0.000 0.500 00030 0.006 0.010 0.000 0.000 0.001 0.000 0.750 00045 0.006 0.017 0.000 0.005 0.007 0.003 1.000 00100 0.006 0.023 0.000 0.005 0.007 0.005 1.250 00115 0.006 0.029 0.000 0.005 0.007 0.006 1.500 00130 0.006 0.036 0.000 0.005 0.007 0.007 1.750 00145 0.006 0.042 0.000 0.005 0.007 0.007 2.000 00200 0.006 0.048 0.000 0.005 0.007 0.007 2.250 00215 0.006 0.055 0.000 0.005 0.007 0.007 2.500 00230 0.006 0.061 0.000 0.005 0.007 0.007 2.750 00245 0.006 0.067 0.000 0.005 0.007 0.007 3.000 00300 0.006 0.073 0.000 0.005 0.007 0.007 3.250 00315 0.006 0.080 0.000 0.005 0.007 0.007 3.500 00330 0.006 0.086 0.000 0.005 0.007 0.007 3.750 00345 0.006 0.092 0.000 0.005 0.007 0.007 9.000 00400 0.008 0.101 0.000 0.007 0.010 0.008 4.250 00915 0.008 0.109 0.001 0.007 0.010 0.009 4.500 00930 0.008 0.118 0.001 0.007 0.010 0.009 4.750 00945 0.008 0.126 0.001 0.007 0.010 0.010 5.000 00500 0.008 0.139 0.001 0.007 0.010 0.010 5.250 00515 0.008 0.193 0.001 0.007 0.010 0.010 5.500 00530 0.008 0.151 0.001 0.007 0.010 0.010 5.750 00545 0.008 0.160 0.001 0.007 0.010 0.010 6.000 00600 0.008 0.168 0.001 0.007 0.010 0.010 6.250 00615 0.011 0.178 0.002 0.009 0.012 0.011 6.500 00630 0.011 0.189 0.002 0.009 0.012 0.011 6.750 00645 0.010 0.199 0.002 0.009 0.012 0.012 7.000 00700 0.011 0.210 0.002 0.009 0.012 0.012 7.250 00715 0.010 0.220 0.002 0.009 0.012 0.012 7.500 00730 0.011 0.231 0.002 0.009 0.012 0.012 7.750 00795 0.011 0.241 0.002 0.009 0.012 0.012 8.000 00800 0.010 0.252 0.002 0.009 0.012 0.012 8.250 00815 0.013 0.265 0.002 0.010 0.015 0.013 8.500 00830 0.015 0.279 0.003 0.012 0.017 0.015 8.750 00845 0.015 0.299 0.003 0.012 0.017 0.016 9.000 00900 0.015 0.309 0.003 0.072 0.017 0.017 9.250 00915 0.017 0.325 0.003 0.014 0.019 0.018 9.500 00930 0.017 0.342 0.003 0.014 0.019 0.019 9.750 00995 0.029 0.361 0.003 0.016 0.022 0.020 10.00 01000 0.019 0.380 0.003 0.016 0.022 0.021 10.25 01015 0.021 0.401 0.004 0.017 0.029 0.022 10.50 01030 0.025 0.926 0.009 0.021 0.029 0.025 10.75 01095 0.032 0.958 0.005 0.026 0.036 0.030 11.00 01100 0.038 0.496 0.006 0.031 0.044 0.036 11.25 01115 0.049 0.590 0.008 0.037 0.051 0.043 11.50 01130 0.055 0.594 0.009 0.095 0.063 0.052 11.75 01145 0.218 0.813 0.037 0.181 0.252 0.127 12.00 01200 0.560 1.392 0.099 0.480 0.668 0.336 12.25 01215 0.092 1.985 0.016 0.077 0.107 0.291 12.50 01230 0.059 1.593 0.010 0.049 0.068 0.227 12.75 01295 0.098 1.592 0.008 0.041 0.056 0.157 13.00 01300 0.038 1.630 0.006 0.032 0.044 0.084 13.25 01315 0.031 1.661 0.005 0.027 0.037 0.031 13.50 01330 0.027 1.688 0.004 0.023 0.032 0.038 13.75 01345 0.023 1.711 0.009 0.020 0.027 0.033 14.00 01900 0.021 1.732 0.003 0.018 0.025 0.028 19.25 01915 0.019 1.751 0.003 0.016 0.022 0.025 14.50 01430 0.017 1.768 0.003 0.014 0.020 0.023 14.75 01445 0.015 1.783 0.002 0.012 0.017 0.020 15.00 01500 0.015 1.798 0.002 0.012 0.017 0.019 15.25 01515 0.015 1.812 0.002 0.01.2 0.017 0.018 15.50 01530 0.013 1.825 0.002 0.011 0.015 0.016 15.75 01545 0.013 1.837 0.002 0.011 0.015 0.016 16.00 01600 0.013 1.850 0.002 0.011 0.015 0.015 16.25 01615 0.013 1.863 0.002 0.011 0.015 0.015 16.50 01630 0.013 1.875 0.002 0.011 0.015 0.015 16.75 01695 0.010 1.886 0.002 0.009 0.012 0.014 17.00 01700 0.010 1.896 0.002 0.009 0.012 0.013 17.25 01715 0.010 1.907 0.002 0.009 0.012 0.013 17.50 01730 0.010 1.917 0.002 0.009 0.012 0.013 17.75 01745 0.010 1.928 0.002 0.009 0.012 0.012 18.00 01800 0.008 1.936 0.001 0.007 0.010 0.012 18.25 01815 0.008 1.995 0.001 0.007 0.010 0.011 18.50 01830 0.008 1.953 0.001 0.007 0.010 0.010 18.75 01845 0.008 1.961 0.001 0.007 0.010 0.010 79.00 01900 0.008 1.970 0.001 0.007 0.010 0.010 19.25 01915 0.008 1.978 0.001 0.007 0.010 0.010 19.50 01930 0.008 1.987 0.001 0.007 0.010 0.010 19.75 01945 0.008 1.995 0.001 0.007 0.010 0.010 20.00 02000 0.006 2.001 0.001 0.005 0.008 0.009 20.25 02015 0.006 2.006 0.001 0.005 0.008 0.008 20.50 02d30 0.006 2.014 0.001 0.005 0.008 0.008 20.75 02095 0.006 2.020 0.001 0.005 0.008 0.008 21.00 02100 0.006 2.026 0.001 0.005 0.008 0.007 21.25 02115 0.006 2.033 0.001 0.005 0.008 0.008 21.50 02130 0.006 2.039 0.001 0.005 0.008 0.008 21.75 02195 0.006 2.095 0.001 0.005 0.008 0.008 22.00 02200 0.006 2.052 0.001 0.005 0.008 0.008 _ 22.25 02215 0.006 2.058 0.001 0.005 0.008 0.008 22.50 02230 0.006 2.069 0.001 0.005 0.008 0.008 22.75 02245 0.006 2.071 0.001 0.005 0.008 0.008 23.00 02300 0.006 2.077 0.001 0.005 0.008 0.008 23.25 02315 0.006 2.083 0.001 0.005 0.008 0.008 23.50 02330 0.006 2.089 0.001 0.005 0.008 0.008 23.75 02345 0.006 2.096 0.001 0.005 0.008 0.008 24.00 00000 0.004 2.100 0.001 0.004 0.005 0.007 24.25 00015 0.000 2.100 0.000 0.000 0.000 0.009 24.50 00030 0.000 2.100 0.000 0.000 0.000 0.002 29.75 00095 0.000 2.100 0.000 0.000 0.000 0.001 2.100 0.330 1.745 1.745 Totals for Watershed in inches over 0.34 acres Rational Coefficient = 0.843 Peak Flow (cfs) = 00.34 e:\clients\bonuceli\wroadway.hyd 6 4TR-55 wORKSHEET 3 Time of Concentzation or Travel Time Project : Bonuccelli's Marietta & Sullivsy : AEG Date : 5-16-00 Location: East End Marietta Checked: Date : Circle One: Present Developed Circle One: Tc Tt through subarea Notes: Space tor as many as two segments per flow type can be used for each worksheet. Inlcude a map, schematic, or description of flow segments. SHEET FLOw (Applicable to Tc only) Segment ID Entrance 1. Surface Description (table 3-1) asphalt 2. Manning's roughness coefF.,n (table 3-1)...... .02 0. 3. Flow Length, L(total L<= 300 ft) ft 226 4. Ten-yr 24-hr rainfall, P2 in 2.1 0. 5. Land slope s ...............................ft/ft 0.0128 0. 6. Tt = 0.007(nL)^.8/P2^.5 s^.4 Compute Tt.... hr 0.0929 0. 0.0924 SHALL047 CONCENTRATED FLOW Segment ID 7. Surface Description (paved or unpaved) 8. Elow Length, L ft 9. S-7atercourse Slope, s ........................ft/ft 0. 0. 10. Average Velocity, v(from figure) ............Et/s 0. 0. 11. Tt = L(3600V) Compute Tt.... hr 0. 0. 0. CHANNEL FLOYI Segment ID 12. Cross Sectional Flow Area, .................ft^2 0. 0. 13. Wetted Perimeter, Pw €t . . 19. Hydraulic Radius r- a/Pw ft . . 15. Channel Slope, s ............................ft/ft 0. 0. 16. Manninq's roughness coeff.,n . 0. 17. V=1.99 r^2/3 s^1/2 / n Compute V ft/s 0. 0. 18. Flow Length, L ft 19. Tt = L(3600V) Compute Tt.... hr 0. 0. 0. 20. Watershed or subarea Tc or Tt add Tc in steps 6,11, and 19 hr 0.092 e:\clients\bonuceli\eguttr55.txt ~ SMADA 6.0 for Windows water.shed Information Watershed Total Area (acres) :0.1660 Impervious Area (acres) :0.1350 Time oF Concentration (min) :5.5 % Impervious Directly Connected :100.00 Additional Abstraction Over Pervious Area (inches) :0.10 Over Impervious Area (inches) :0.01 Infiltration Characteristics: Max Infzltzation Capacity (in) :999.00 SCS Curve Number for Pervious :61 Initzal Abstraction Factor :0.20 e:\clients\bonuceli\eroadway.shd 0 . , Watershed Hydrograph 0.20 ~ 0.15- - - - - ~ Flow ~ (Cfs) 0.10 - - 0.05 ~ 0.00 0 5 10 1'5 T 2~0 2i5 Time (hours) • Y Hydrograph Type :SCS 100 Hydzogranh Time Time Rain C Rain Infiltration Excess E}:cess Outflow (hr) HHMM (in) (in) (in) (in) (cfs) (cfs) 0.250 00015 0.004 0.009 0.000 0.000 0.000 0.000 0.500 00030 0.006 0.010 0.000 0.000 0.000 0.000 0.750 00045 0.006 0.017 0.000 0.005 0.003 0.001 1.000 00100 0.006 0.023 0.000 0.005 0.003 0.002 1.250 00115 0.006 0.029 0.000 0.005 0.003 0.003 1.500 00130 0.006 0.036 0.000 0.005 0.003 0.003 1.750 00145 0.006 0.042 0.000 0.005 0.003 0.003 2.000 00200 0.006 0.098 0.000 0.005 0.003 0.003 2.250 00215 0.006 0.055 0.000 0.005 0.003 0.003 2.500 00230 0.006 0.061 0.000 0.005 0.003 0.003 2.750 00245 0.006 0.067 0.000 0.005 0.003 0.003 3.000 00300 0.006 0.073 0.000 0.005 0.003 0.003 3.250 00315 0.006 0.080 0.000 0•.005 0.003 0.003 3.500 00330 0.006 0.086 0.000 0.005 0.003 0.003 3.750 00395 0.006 0.092 0.000 0.005 0.003 0.003 4.000 00400 0.008 0.101 0.000 0.007 0.005 0.004 9.250 00415 0.008 0.109 0.002 0.007 0.005 0.004 9.500 00430 0.008 0.1.18 0.002 0.007 0.005 0.009 9.750 00495 0.008 0.126 0.002 0.007 0.005 0.005 5.000 00500 0.008 0.139 0.002 0.007 0.005 0.005 5.250 00515 0.008 0.143 0.002 0.007 0.005 0.005 5.500 00530 0.008 0.151 0.002 0.007 0.005 0.005 5.750 00545 0.008 0.160 0.002 0.007 0.005 0.005 6.000 00600 0.008 0.168 0.002 0.007 0.005 0.005 6.250 00615 0.011 0.178 0.002 0.009 0.006 0.005 6.500 00630 0.011 0.189 0.002 0.009 0.006 0.005 6.750 00645 0.010 0.199 0.002 0.009 0.006 0.006 7.000 00700 0.011 0.210 0.002 0.009 0.006 0.006 7.250 00715 0.010 0.220 0.002 0.009 0.006 0.006 7.500 00730 0.011 0.231 0.002 0.009 0.006 0.006 7.750 00745 0.011 0.241 0.002 0.009 0.006 0.006 8.000 00800 0.010 0.252 0.002 0.009 0.006 0.006 8.250 00815 0.013 0.265 0.002 0.010 0.007 0.006 8.500 00830 0.015 0.279 0.003 0.012 0.008 0.007 8.750 00845 0.015 0.294 0.003 0.012 0.008 0.007 9.000 00900 0.015 0.309 0.003 0.012 0.008 0.008 9.250 00915 0.017 0.325 0.003 0.019 0.009 0.008 9.500 00930 0.017 0.342 0.003 0.014 0.009 0.009 9.750 00995 0.019 0.361 0.009 0.015 0.010 0.009 10.00 01000 0.019 0.380 0.004 0.015 0.010 0.010 10.25 01015 0.021 0.901 0.004 0.017 0.011 0.011 10.50 01030 0.025 0.926 0.005 0.020 0.014 0.012 10.75 01045 0.032 0.958 0.006 0.026 0.017 0.014 11.00 01100 0.038 0.996 0.007 0.031 0.021 0.017 11.25 01115 0.044 0.590 0.008 0.036 0.024 0.020 11.50 01130 0.055 0.599 0.010 0.094 0.030 0.024 11.75 01145 0.218 0.813 0.041 0.178 0.119 0.060 12.00 01200 0.580 1.392 0.108 0.471 0.315 0.160 12.25 01215 0.092 1.985 0.017 0.075 0.051 0.136 12.50 01230 0.059 1.543 0.011 0.098 0.032 0.109 12.75 01245 0.048 1.592 0.009 0.040 0.027 0.069 13.00 01300 0.038 1.630 0.007 0.031 0.021 0.037 13.25 01315 0.031 1.661 0.005 0.026 0.017 0.023 13.50 01330 0.027 1.688 0.005 0.023 0.015 0.019 13.75 01345 0.023 1.711 0.004 0.019 0.013 0.016 14.00 01900 0.021 1.732 0.004 0.017 0.012 0.019 14.25 01415 0.019 1.751 0.003 0.016 0.011 0.012 19.50 01430 0.017 1.768 0.003 0.014 0.009 0.011 14.75 01445 0.015 1.783 0.002 0.012 0.008 0.010 15.00 01500 0.015 1.798 0.002 0.012 0.006 0.009 15.25 01515 0.015 1.812 0.002 0.012 0.008 0.008 15.50 01530 0.013 1.825 0.002 0.011 0.007 0.008 15.75 01595 0.013 1.837 0.002 0.011 0.007 0.007 16.00 01600 0.013 1.850 0.002 0.011 0.007 0.007 16.25 01615 0.013 1.863 0.002 0.011 0.007 0.007 16.50 01630 0.013 1.875 0.002 0.011 0.007 0.007 16.75 01645 0.010 1.886 0.002 0.009 0.006 0.007 17.00 01700 0.010 1.896 0.002 0.009 0.006 0.006 17.25 01715 0.010 1.907 0.002 0.009 0.006 0.006 17.50 01730 0.010 1.917 0.002 0.009 0.006 0.006 17.75 01745 0.010 1.928 0.002 0.009 0.006 0.006 18.00 01800 0.008 1.936 0.001 0.007 0.005 0.005 18.25 01815 0.008 1.945 0.001 0.007 0.005 0.005 18.50 01830 0.008 1.953 0.001 0.007 0.005 0.005 18.75 01845 0.008 1.961 0.001 0.007 0.005 ' 0.005 19.00 01900 0.008 1.970 0.001 0.007 0.005 0.005 19.25 01915 0.008 1.978 0.001 0.007 0.005 0.005 19.50 01930 0.008 1.987 0.001 0.007 0.005 0.005 19.75 01945 0.008 1.995 0.001 0.007 0.005 0.005 20.00 02000 0.006 2.001 0.001 0.005 0.004 0.004 20.25 02015 0.006 2.008 0.001 0.005 0.009 0.004 20.50 02630 0.006 2.014 0.001 0.005 0.004 0.004 20.75 02045 0.006 2.020 0.001 0.005 0.009 0.004 21.00 02100 0.006 2.026 0.001 0.005 0.009 0.004 21.25 02115 0.006 2.033 0.001 0.005 0.004 0.009 21.50 02130 0.006 2.039 0.001 0.005 0.004 0.009 21.75 02145 0.006 2.095 0.001 0.005 0.004 0.009 22.00 02200 0.006 2.052 0.001 0.005 0.004 0.004 22.25 02215 0.006 2.058 0.001 0.005 0.004 0.009 22.50 02230 0.006 2.069 0.001 0.005 0.004 0.004 22.75 02245 0.006 2.071 0.001 0.005 0.004 0.009 23.00 02300 0.006 2.077 0.001 0.005 0.004 0.009 23.25 02315 0.006 2.083 0.001 0.005 0.009 0.004 23.50 02330 0.006 2.089 0.001 0.005 0.009 0.004 23.75 02395 0.006 2.096 0.001 0.005 0.004 0.004 29.00 00000 0.004 2.100 0.001 0.004 0.002 0.003 29.25 00015 0.000 2.100 0.000 0.000 0.000 0.002 24.50 00030 0.000 2.100 0.000 0.000 0.000 0.001 24.75 00045 0.000 2.100 0.000 0.000 0.000 0.000 2.100 0.360 1.713 1.713 Totals for Watershed in inches over 0.17 acres Rational Coefficient = 0.829 Peak Flow (cfs) = 00.16 e:\clients\bonuceli\eroadway.hyd ~ 4TR-55 GJORKSHEET 3 Time of Concentration or Travel Time Project : Bonuccelli's Marietta & Su1livBy : AEG Date : 5-16-00 Location: PreDev Site Checked: Date : Circle One: Present Developed Circle One: Tc Tt through subarea Notes: Space for as many as two segments per flow type can be used for each worksheet. Inlcude a map, schematic, or description of flow segments. SHEET FL0W (Applicable to Tc only) Segment ID NorthEast 1. Surtace Description (table 3-1) Meadow 2. Manning's roughness coeff.,n (table 3-1) .03 0. 3. Flow Length, L(total L<= 300 ft) ft 300 9. Ten-yr 24-hr rainfall, P2 in 2.1 0. 5. Land slope s ...............................ft/ft 0.013 0. 6. Tt = 0.007(nL)^.8/P2^.5 s^.9 Compute Tt.... hr 0.1591 0. 0.1591 SHALLOWI COPtCENTRATED FLOW Seqment ID Shal.low Ch 7. Surface Description (paved or unpaved) Meadow 8. Flow Length, L ft 708 9. 6•latercourse Slope, s ........................ft/tt 0.013 0. 10. Averaqe Velocity, v(from figure) ............ft/s 0.75 0. 11. Tt = L(3600v) Compute Tt.... hr 0.2622 0. 0.2622 CHANNEL FLOW Segment ID 12. Cross Sectional E'low Area, .................ft^2 0. 0. 13. 6vetted Perimeter, Pw ft . . 19. Hydraulic Radius r= a/Pw ft . . 15. Channel Slope, s ............................ft/ft 0. 0. 16. Manning's roughness coeff.,n . 0. 17. V=1.99 r^2/3 s^1/2 / n Compute v.......... ft/s 0. 0. 18. Flow Length, L ft 19. Tt = L(3600V) Compute Tt.... hr 0. 0. 0. 20. Watershed oz subazea Tc or Tt add Tc in steps 6,11, and 19 hr 0.421 e:\clients\bonuceli\exsttr55.txt ~ SMADA 6.0 for Windows WatErshed Tnformation water.shed Total Area (acres) :21.1500 zmpervious Area (acres) :0.0000 Time of Concentration (min) :25.3 % Impervzous Directly Connected :100.00 Additional Abstraction Over Pervious Area (inches) :0.10 Over Impervious Area (inches) :0.01 Infiltration Characteristics: Max Infiltration Capacity (in) :999.00 SCS Curve Number for Pervxous :58 Initial Abstraction Factor :0.20 e:\clients\bonuceli\exst.shd ~ w Watershed Hydrograph 0.10 0.08 Flow 0.06 ~ - (cfs) 0.04 ~ - . 0.02 ~ - - - , 0.00 0 5 1'0 2'0 2'5 30 Time (hours) 4Hyd~:cltraph Type :SCS 100 Hydrograph Time Time Rain C Rain Infiltration Excess Excess Outflow (hr) HHMM (in) (in) (in) (in) (cfs) (cfs) 0.250 00015 0.009 0.004 0.000 0.000 0.000 0.000 0.500 00030 0.006 0.01.0 0.000 0.000 0.000 0.000 0.750 00045 0.006 0.017 0.000 0.000 0.000 0.000 1.000 00100 0.006 0.023 0.000 0.000 0.000 0.000 1.250 00115 0.006 0.029 0.000 0.000 0.000 0.000 1.500 00130 0.006 0.036 0.000 0.000 0.000 0.000 1.750 00145 0.006 0.042 0.000 0.000 0.000 0.000 2.000 00200 0.006 0.098 0.000 0.000 0.000 0.000 2.250 00215 0.006 0.055 0.000 0.000 0.000 0.000 2.500 00230 0.006 0.061 0.000 0.000 0.000 0.000 2.750 00245 0.006 0.067 0.000 0.000 0.000 0.000 3.000 00300 0.006 0.073 0.000 0.000 0.000 0.000 3.250 00315 0.006 0.080 0.000 0.000 0.000 0.000 3.500 00330 0.006 0.086 0.000 0.000 0.000 0.000 3.750 00345 0.006 0.092 0.000 0.000 0.000 0.000 9.000 00400 0.008 0.101 0.001 0.000 0.000 0.000 4.250 00415 0.008 0.109 0.008 0.000 0.000 0.000 4.500 00930 0.008 0.116 0.008 0.000 0.000 0.000 9.750 00945 0.008 0.126 0.008 0.000 0.000 0.000 5.000 00500 0.008 0.139 0.008 0.000 0.000 0.000 5.250 00515 0.008 0.193 0.008 0.000 0.000 0.000 5.500 00530 0.008 0.151 0.008 0.000 0.000 0.000 5.750 00545 0.008 0.160 0.008 0.000 0.000 0.000 6.000 00600 0.008 0.166 0.008 0.000 0.000 0.000 6.250 00615 0.011 0.178 0.011 0.000 0.000 0.000 6.500 00630 0.011 0.189 0.011 0.000 0.000 0.000 6.750 00695 0.010 0.199 0.010 0.000 0.000 0.000 7.000 00700 0.011 0.210 0.011 0.000 0.000 0.000 7.250 00715 0.010 0.220 0.010 0.000 0.000 0.000 7.500 00730 0.011 0.231 0.011 0.000 0.000 0.000 7.750 00795 0.011 0.241 0.011 0.000 0.000 0.000 " 8.000 00800 0.010 0.252 0.010 0.000 0.000 0.000 8.250 00815 0.013 0.265 0.013 0.000 0.000 0.000 8.500 00830 0.015 0.279 0.015 0.000 0.000 0.000 8.750 00845 0.015 0.294 0.015 0.000 0.000 0.000 9.000 00900 0.015 0.349 0.015 0.000 0.000 0.000 9.250 00915 0.017 0.325 0.017 0.000 0.000 0.000 9.500 00930 0.017 0.342 0.017 0.000 0.000 0.000 9.750 00995 0.019 0.361 0.07.9 0.000 0.000 0.000 10.00 01000 0.019 0.380 0.019 0.000 0.000 0.000 10.25 01015 0.021 0.401 0.021 0.000 0.000 0.000 10.50 01030 0.025 0.426 0.025 0.000 0.000 0.000 10.75 01045 0.032 0.458 0.032 0.000 0.000 0.040 11.00 01100 0.036 0.496 0.038 0.000 0.000 0.000 11.25 01115 0.044 0.590 0.044 0.000 0.000 0.000 11.50 01130 0.055 0.599 0.055 0.000 0.000 0.000 11.75 01145 0.218 0.813 0.218 0.000 0.000 0.000 12.00 01200 0.580 1.392 0.580 0.000 0.000 0.000 12.25 01215 0.092 1.485 0.092 0.000 0.000 0.000 12.50 01230 0.059 1.543 0.059 0.000 0.000 0.000 12.75 01295 0.048 1.592 0.098 0.000 0.022 0.001 13.00 01300 0.038 1.630 0.037 0.001 0.055 0.005 13.25 01315 0.031 1.661 0.031 0.001 0.071 0.011 13.50 01330 0.027 1.688 0.026 0.001 0.079 0.017 13.75 01345 0.023 1.711 0.022 0.001 0.080 0.024 19.00 01900 0.021 1.732 0.020 0.001 0.083 0.030 19.25 01415 0.019 1.751 0.018 0.001 0.083 0.036 19.50 01930 0.017 1.768 0.016 0.001 0.080 0.092 14.75 01445 0.015 1.783 0.014 0.001 0.075 0.097 15.00 01500 0.015 1.798 0.019 0.001 0.080 0.052 15.25 01515 0.015 1.812 0.014 0.001 0.089 0.056 15.50 01530 0.013 1.825 0.012 0.001 0.076 0.060 15.75 01545 0.013 1.837 0.012 0.001 0.079 0.064 16.00 01600 0.013 1.850 0.012 0.001 0.063 0.067 16.25 01615 0.013 1.863 0.012 0.001 0.086 0.070 16.50 01630 0.013 1.875 0.012 0.001 0.089 0.079 16.75 01695 0.010 1.886 0.010 0.001 0.077 0.076 17.00 01700 0.010 1.896 0.010 0.001 0.079 0.077 17.25 01715 0.010 1.907 0.010 0.001 0.081 0.079 17.50 01730 0.010 1.917 0.010 0.001 0.084 0.080 17.75 01745 0.010 1.928 0.009 0.001 0.086 0.081 18.00 01800 0.008 1.936 0.008 0.001 0.070 0.081 18.25 01815 0.008 1.995 0.008 0.001 0.072 0.060 18.50 01830 0.008 1.953 0.008 0.001 0.073 0.080 18.75 01845 0.008 1.961 0.008 0.001 0.075 0.079 19.00 01900 0.008 1.970 0.008 0.001 0.076 0.079 19.25 01915 0.008 1.978 0.007 0.001 0.077 0.078 19.50 01930 0.008 1.987 0.007 0.001 0.079 0.078 19.75 01995 0.008 1.995 0.007 0.001 0.080 0.078 20.00 02000 0.006 2.001 0.006 0.001 0.061 0.077 20.25 02015 0.006 2.008 0.006 0.001 0.062 0.076 20.t0` '02t30 0.006 2.014 0.006 0.001 0.063 0.079 20.75 02095 0.006 2.020 0.006 0.001 0.063 0.073 21.00 02100 0.006 2.026 0.006 0.001 0.069 0.072 21.25 02115 0.006 2.033 0.006 0.001 0.065 0.071 21.50 02130 0.006 2.039 0.006 0.001 0.066 0.070 21.75 02195 0.006 2.045 0.006 0.001 0.066 0.069 22.00 02200 0.006 2.052 0.006 0.001 0.067 0.069 22.25 02215 0.006 2.058 0.006 0.001 0.068 0.068 22.50 02230 0.006 2.064 0.005 0.001 0.069 0.068 22.75 02245 0.006 2.071 0.005 0.001 0.069 0.068 23.00 02300 0.006 2.077 0.005 0.001 0.070 0.068 23.25 02315 0.006 2.083 0.005 0.001 0.071 0.068 23.50 02330 0.006 2.089 0.005 0.001 0.072 0.068 23.75 02345 0.006 2.096 0.005 0.001 0.073 0.068 24.00 00000 0.004 2.100 0.009 0.001 0.099 0.067 24.25 00015 0.000 2.100 0.000 0.000 0.000 0.063 24.50 00030 0.000 2.100 0.000 0.000 0.000 0.057 29.75 00045 0.000 2.100 0.000 0.000 0.000 0.051 25.00 00100 0.000 2.100 0.000 0.000 0.000 0.046 25.25 00115 0.000 2.100 0.000 0.000 0.000 0.090 25.50 00130 0.000 2.100 0.000 0.000 0.000 0.036 25.75 00145 0.000 2.100 0.000 0.000 0.000 0.031 26.00 00200 0.000 2.100 0.000 0.000 0.000 0.027 26.25 00215 0.000 2.100 0.000 0.000 0.000 0.023 26.50 00230 0.000 2.100 0.000 0.000 0.000 0.019 26.75 00245 0.000 2.100 0.000 0.000 0.000 0.016 27.00 00300 0.000 2.100 0.000 0.000 0.000 0.013 27.25 00315 0.000 2.100 0.000 0.000 0.000 0.010 27.50 00330 0.000 2.100 0.000 0.000 0.000 0.008 27.75 00345 0.000 2.100 0.000 0.000 0.000 0.006 28.00 00400 0.000 2.100 0.000 0.000 0.000 0.004 28.25 00915 0.000 2.100 0.000 0.000 0.000 0.002 28.50 00930 0.000 2.100 0.000 0.000 0.000 0.001 28.75 00995 0.000 2.100 0.000 0.000 0.000 0.001 29.00 00500 0.000 2.100 0.000 0.000 0.000 0.000 2.100 1.961 0.039 0.039 Totals for Watershed in inches over 21.15 acres Rational Coefficient = 0.066 Peak F].ow (cfs) v 00.08 e:\clients\bonuceli\exst.hyd l a ~ a. S I~ O K A N E U l,l" T Y DN[SIOIV OF EiVGWEERING AND ROADS A DIVISION OF THE PUBLIC WORKS DEPARTMENT William A. Johns, P.E., County Engineer July 10, 2000 Alan Gay, P.E. TechCon 1230 E. Front Ave. Spokane, WA 99202 SUBJECT: BSP 64 - Marietta at Sullivan (Bonucelli) l" Submittal Gentlemen: We have conducted a cursory review of your June 29, 2000 subnuttal of Design Documents for this project, and we have found that the submittal generally does not conform to the requirements of the Spokane County Standards for Road and Sewer Construction or the Guidelines for StormwateY Management. We are, therefore, unable to accept your submittal for review at this time. The attached comment list contains the items of concern which we discovered, and it is not to be construed as being comprehensive. If you have any questions about this review, please contact Ed Parry at 477-3600. Thank you. Sincerely, William A. Johns, P. E. Spokane County Engineer Edwar J. arry, P.E. Plan Review Engineer encl.: Design Documents - plans & calculaiions Comments (1 page) cc: project file reviewer (comments only) Sponsor: Bob Bonucelli P.O. Box 141449, Spokane, WA 99214 1026 W. Broadway Ave. 9 Spokane, WA 99260-0170 •(509) 477-3600 FAX: (509) 477-7655 (2nd Floor) 477-7478 (3rd Floor) • TDD: (509) 477-7133 r` . Alan Gay, P.E. BSP 64 - Marietta at Sullivan (Bonucelli) 0 Submittal July 10, 2000 Page 2 of 2 , Items needed: Plans 1) Need to provide a cul-de-sac profile, around the curbline. One of the curb return points is typically taken as the start of the profile, and the curbline is then "unrolled' around to the other curb return point on the opposite side of the road. See attached sketch 2) Is the pipe at the west end of Marietta needed to convey road drainage? If so, the pipe invert (1996.6 at west end of cul-de-sac) needs to be coordinated with the pond floor elevation at the drywells at 0+61 (1997.27). 3) Need to indicate cwb cut stations for the cutb cuts near station 5+00 4) Top-of-berm elevations are needed. Berms should be provided to develop ponding in the vicinity of the drywells at 3+66 5) The 3% road grade requires that intermediate berms will be needed to develop the water quality ("208") treatment volume intended along Marietta. Only if a swale is less than 100 feet long is a slope up to 1% considered "flat". Other conditions require that the volume be adjusted for the slope of the swale 6) Need to provide elevations at beginning, middle, and end of cwb returns. Need to indicate stations of curb PT at cul-de-sac 7) Is the large swale at the southwest end of the site needed, if the various parcels are to manage their own drainage? If so, maintenance access is needed, as well as some means to dispose of the volume. A Property Owners' Association will be need to be formed so that there will be an entity responsible for maintenance. Otherwise, 8) If infiltration through the pond floor is proposed, a Design Deviation Request needs to be submitted to the County Engineer for approval. If infiltration is still intended as the disposal mechanism, a Design Deviation Request form is attached as requested. 9) "Curb cut to swale" detail - needs to conform to County Standard Plan B-8 10) "Swale" details - need to indicate side slopes Calculatioas l) Drainage calcs need to show how the required 208 volume is provided for the contributing roadway area 2) Drainage calculations need to show how the weighted "C" factor is obtained 3) Drainage calculations are needed for the easterly basins on Marietta (drywells at 3+66), and for the middle Marietta basin. 4) A basin map needs to be included with the drainage caiculations. The map needs to clearly show the basins associated with the drywells. 5) The outflow rate for the westerly basin can combine both drywells, if the drywells are piped together, or if the swale floor between the two drywells is at the same elevation. Otherwise, each drywell serves a discrete drainage basin 6) Cwb opening capacity calculations are needed Typical Section Data MARIETfA WEST OF SULLIVAN Roadway half width 20 ft. Road Name: Marietta Left or Right: Right Curb Type: Type R, Spokane County Cufi Ht: 4 inches (through STA 5+66) Station Interval: 25 feet Curb Ht: 6 inches (STA 5+66 to STA 6+00) • "W" MINIMUM MAXIMUM E/P TO CENTER % SLOPE EDGE DIST. % SLOPE DIST. CURB EL. CURB EL. SELECTED GUTTER SELECTED LINE CENTER PAVEMENT C/L TO C/L TO E/P FROM E/P (-4.5% from (•2% from CURB DESIGN TOP CURB GUTTER STATION ELEVATION LINE ELEVATION E/P E/P % SLOPE TO CURB E/P + CURB HT) E/P + CURB Hl) ELEVATION % GRADE % GRADE ELEVATION STATION 66.38 1998.19 na 1997.82 (GUTTER) TOC ELEV= 1998.12 66,38 75 1998,45 3.02 1996.08 18.50 -2.00 3.02 1.50 1998.35 1998.38 1998.38 -0.21 3.02 1998.05 75 100 1999.19 2.96 1998.82 18.50 -2.00 2.96 1.50 1999.09 1999.12 1999.12 -0.21 2.96 1998.79 100 125 1999.95 3.04 1999.58 18.50 -2.00 3.04 1.50 1999.85 1999.88 1999.88 -2.00 3.04 1999.55 125 150 2000.10 3.00 2000.33 18.50 -2.00 3.00 1.50 2000.60 2000.63 2000.63 -2.00 3.00 2000.3 150 175 2001.45 3.00 2001.06 18.50 -2.00 3.00 1.50 2001.35 2001,38 2001.38 -2.00 3.00 2001.05 175 200 2002.20 3.00 2001.83 18.50 -2.00 3.00 1.50 2002.10 2002,13 2002.13 -2.00 3.00 2001.8 200 225 2002.95 3.00 2002.58 18.50 -2.00 3.00 1.50 2002.85 2002,88 2002.88 -2.00 3.00 2002,55 225 250 2003.70 3,00 2003.33 18.50 -2.00 3.00 1,50 2003.60 2003,63 2003,63 -2.00 3.00 2003.3 250 275 2004.45 3.00 2004.08 18.50 -2.00 3.00 1.50 2004,35 2004.38 2004.38 -2.00 3.00 2004.05 275 300 2005.19 2.96 2004.82 18.50 -2.00 2.96 1.50 2005.09 2005.12 2005.12 -2.00 2.96 2004.79 300 325 2005.94 3.00 2005,57 18.50 -2.00 3.00 1,50 2005.84 2005.87 2005.87 -2.00 3,00 2005.54 325 350 2006.69 3.00 2006.32 18.50 -2.00 3.00 1.50 2006.59 2006.62 2006.62 -2.00 3.00 2006.29 350 375 2007.44 3.00 2007.07 18.50 -2.00 3,00 1.50 2007.34 2007.37 2007.37 -2,00 3.00 2007.04 375 400 2008.19 3.00 2007,82 18.50 -2.00 3.00 1.50 2008,09 2008.12 2008.12 -2.00 3.00 2007.79 400 425 2008.51 1.28 2008.14 18.50 -2.00 128 1.50 2006.41 2008,44 2008.44 •2.00 1.28 2008.11 425 450 2008.84 1,32 2008,47 18.50 -2,00 1.32 1.50 2006.74 2008.77 2008.77 -2,00 1.32 2008.44 450 475 2009.16 1.28 2008.79 18.50 -2.00 1.28 1.50 2009.06 2009,09 2009.09 -2.00 1.28 2008.76 475 500 2009.48 1.28 2009.11 18,50 -2.00 1.28 1.50 2009.38 2009,41 2009.41 -2.00 1.28 2009.08 500 525 2009.57 0.36 2009,20 18.50 -2,00 0.36 1.50 2009.47 2009,50 2009.50 -2.00 0.36 2009.17 525 550 2009.67 0.40 2009,30 18.50 -2.00 0.40 1.50 2009.57 2009,60 2009.60 -2,00 0,40 2009.27 550 575 2009.76 0.36 2009,39 18.50 -2.00 0.36 1.50 •2009.82 2009.86 2009.69 -2.00 0,36 2009,19 575 600 2009.78 0,08 2009.41 18.50 -2.00 0.08 1.50 2009.84 2009.88 2009.71 -2.00 0.08 2009.21 600 NOTES: 1. AT STA 6+00, THE EXISTING CURB CONSISTS OF SPOKANE COUNTY TYPE "B" AS CONSTRUCTED ON SULLIVAN ROAD. • . p,N EG Q.v oF wASy ~ AITv ~ ,Yy y , O Z 4 v ~29144 ~ - ~Sf~NAL~G f ExPiRES Bonuccelli Development Marietta & Sullivan 04-Jun-9f Roadway Design Pavement Design Calculations for Marietta: Soil Type: Garrison Gravely Loam GgA GM Average Daily Traffic (ADT) Based on Parameters for Pavement Desigr Given by Spokane Coun- - Actual 9 Comm/Ind Sites, avg. 137.5' frontage, avg. 200-600 vehicles per day ESAL . Number factor total Semi Trucks 30 2.87 86 - E. Refuse +1/7 1.03 0 Q,v oF wASDelivery Tr. 20 1 20 •,~c~ Automobiles 700 0.42 294 total: 400 ESAL ~ Required by Spokane County Design Matix for Local Acces: 29194 2" asphalt ACP Class A 2" asPhalt ACP Class E NAL~G 8" crushed gravel base course EXPIRES Confirm using The Asphalt Institute Design Manuaf MS-1: Traffic EAL: 400 = 4.00E+02 Mr of soil: 10000 psi or greater (Soil report for similar site in Garrison Gravely Lc Assume 2" asphalt surface (ACP Class A) From Design Chart VI-1: 3 inch minimum of total Asphalt required, 4" Untreated Aggregate Base Cc Therefore, Design is conservative. TECHCON, INC. ~ v TECHIVICAL CONSULTANTS ~ June 28, 2000 Mr. Ed Perry RECE~VED Spokane County Engineers j U~ L 9 2000 1026 W. Broadway Spokane, WA 99260 SpOONE CouIvr-r ENGiNEER RE: Certification of Soil for BSP 64-98 Dear Mr. Perry: As you requested, this letter certifies that the soils on site at Robert Bonuccelli's Marietta and Sullivan Development, known as BSP 64-98, are consistent with the description for Garrison soils in the USDA Soil Conservation Service (SCS) Spokane County Soils report published in 1968. This certification is based on my observations of the trench used for construction of the sewer on the site on June 12 and 13, 2000. In that trench I observed a high proportion of cobbles and sand. Fines were either sand or silt loam with nearly no clay. I performed a field test of the soil by moistening the soil and attempting to roll it into a bead. The bead did not hold shape at all, indicating low plasticity and therefore a low clay content. The drai_nage report accompanying this submittal includes a copy of the soils map that shows the subject site. This soils map shows the site is underlain by Garrison Very Stony Loam and Garrison Gravely Loam. If you have any questions or comments regarding this analysis or any other engineering aspect of the proposed project, please contact me to address them. Sincerely, . ~ ~ Alan E. Gay, P.E. Project Manager East 12-10 M ront Averiuc, 5pol:ane, Washington, 99202-2148 - Tel (509) 536-0406 - Fax (509) 536-0565 Professional Lnbineers •(:ertiticd Hm•ironmenkal Specialists • Project 11•Ianagers ~ A. - CONTRACT CIVIL ENGINEERING SERVICES Requirements: Construction Phase Review Civil Engineering Project Location: Marietta Avenue west of Sullivan Road, Spokane, Washington Client Name: Robert A. Bonuccelli Purpose: Provide construction phase civil engineering review of construction for development of commercial and industrial lots, including drainage improvements, pavement, and utility trenches. 1. Cost Estimate: The cost for the professional services (billed at $75/hour) are estimated to be a maximum oF $3, 0110. 00. Services in addition to those in this contract will be incurred only with prior authorization at a rate of $75 per hour plus expenses. Limited travel to/from site is covered under this contract. 2. Terms: Lump Sum total 15 days after receipt of invoice. To be progress billed at the end of each calendar month for work performed to the date of invoice. 3. Scope of work: See letter dated September 11, 1997. If the client requests implementation of any additional work, said work shall follow standard engineering practice. 4. Project Schedule: TechCon will begin work on the project upon notification by the owner or the owner's representative. Work will be completed within two weeks of completion of construction, unless delayed by actions outside the control of TechCon. 5. Clienf Requirements: The ciient shall provide TechCon, Inc. (TechCon) the following: • Fax copy of the signed agreement to TechCon denoting authorization to proceed. Page 1 of 2 , R• - • Access to existing records, documents, and/or files regarding the project, as necessary to complete the engineering report. ~ The client will be responsible for any permit fees regarding this project. TechCon is pleased to have the opportunity to work with you again. Please sign and date at the location below, fax me a copy at (509) 536-0565, and mail a copy of the original at your convenience. Our mailing address is: TECIiCON, INC. East 1230 Front Avenue Spokane, Washington 99202-2148 Should you have any questions, please call me at (509) 536-0406. Sincerely, ~ ~ - Daniel L. Autrey, C. s. Principal AUTHORIZA,TION TO PROCEED The below signature hereby authorizes and provide.s TechCon authoriry to implement and perorm the needed site investigation work to meet Industry Standarris. I understand thctt the terms of the contract are Net 15 days from the date of initial involce. Client Name: Print/T'ype Client Signature: ~~~G~~~_ • Date: Page 2 of 2 r~ 2'~ Alan Gay, P.E. BSP 64 - Marietta at Sullivan (BonuceW) ls` Submittal July 14, 2000 Page 2 of 2 Items needed: lans Need to provide a cul-de-sac profile, around the curbline. One of the curb return points is typically taken as the start of the profile, and the curbtine is then "unrolled' around to the other curb return point on the opposite side of the road. See attached sketch Is the pipe at the west end of Marietta needed to convey road drainage? if so, the pipe invert (1996.6 at west end of cul-de-sac) needs to be coordinated with the pond floor elevation at the drywells at 0+61 (1997.27). Need to indicate curb cut stations for the curb cuts nea.r station 5+00~ ~ Top-of-berm elevations are needed. Berms should be provided to develop ponding in the vicinity of the drywells at 3+66 .5~ The 3% road grade requires that intermediate berms will be needed to develop the water quality ("2U8") treatment volume intended along Marietta Only if a swale is less than l00 feet long is a slope up to 1% considered "flat". Other conditions require that the volume be adjusted for the slope of the swale ~ Need to provide elevations at begiru~ing, middle, and end of curb returns. Need to indicate stations of curb PT at cul-de-sac ~Is the large swale at the southwest end of the site needed, if the various parcels are to manage their own , drainage? If so, maintenance access is needed, as well as some means to dispose of the volume. A Property Owne ' Association will be need to be formed so that there will be an entity responsible for maintenance. t e , If infiltration through the pond floor is proposed, a D~sign Deviation Request needs to be submitted to the County Engineer for approval. If infiltration is still intended as the disposal mech~; ism a Design Deviation Request form is attached as requested.~~G~S ~LL ~N~(L~~'~', ~"Curb cut to swale" detail - needs to conform to County Standard Plan B-8 G~~~' "Swale" details - need to indicate side slopes alculations 1) Drainage calcs need to show how the required 208 volume is provided for the contributing rQadway area Drainage calculations need to show how the weighted "C" factor is obtained ~ij Drainage calculations are ne~ded for the easterly basins on Marietta (drywells at 3+66), and for the middle Marietta basin. ~ A basin map needs to be included with the drainage calculations. The map needs to clearly show the basins associated with the drywells. (~,~1; ~,~~r.~ ,/S'~ The outflow rate for the westerly basin can combine both drywells, if the drywells are piped together, or if the swale floor between the two drywells is at the same elevation. Otherwise, each drywell serves a discrete drainage basin7~.~'~rTc~ hs s~~?,~5~ ~srNs ~Curb opening capacity calculations are needed ~ , ~s~7~'✓~'; ~ k ~ ca ~ hl~~ _ ~ , ' ~ ~ ~ ~ a~Q i' ° ~ r~ ~ ,l~f~ ~''~vv~ ~ ~ ~ ~ ~ ~~W~~~ ~ ~ ~~~~~~z~ \ ~ ~ ~ ~ l ~ ~ . I I I I~ 1 I ~ ~ / ~ ~ I I I I ~ / / ~ ~ I D lP x . filo;a~~s P ' e or X 1; NN ~ Q ' flf~ y ~ ~ 1 ~ I / j j~» ~ YV ~ ~i`Y1~1~!'!N1~t ~ •i~t~~ ~ yyy777 ~ . Q t I ' PS~ / ~ ~ ~a G / . YP . ~ . , . . . , n.r. - - n~ . . i 1 ~ ~ ~ ~ ➢ ~ g ~ ~8 - . ~ .l. . . . ( + fJi'rii~o.4i+ow • cr✓i' ..~aai+ . . / X fagc0 g° ~ P~ ~P ~ f ~ ~ P ~ • _-p ~bP ~ X : . m i . ~ ' r ~ ; X m l m 00 J I I ~ ~ ~ ' ► 0 I ~ i ---J qh ~P REQUEST FOR DESIGN DEVIATION ~ $30.00 DATE t ROAD NAME CRP/RID ' NAME OF PLAT ~ c~-,d u ~'r ,a/f~r S ~ ~ /~a v' 4 `C-j # C~. 114 Plat # ADDRESS OF BLDG NANiE OF BLDG PROJECT BLDG#B9 S 1/ T ZSdI R~~E FEDERAIJSTATE PROJECT # ~ PROJECT LIMITS EXISTING CONDITIONS: PROPOSED IMPROVEMENTS: ~~dVl@ 3 ~j, ROAD WIDTH ROAD SURFACE AVG. DAII.Y TRAFFIC Current Traffic Count Design Year Tra'r-ffic Count , PROJECT DESCRIP'TION ~~4~-~ ~ ~ ~ . LC.e, . / \~i c4 {L../ / _14p - -S Q_ C o _j PROPOSED DESIGN DEVIATION IR6 - G~~ •~trc7~-~. C~- ~-S'~ C._ L{_ i!' ~ ` ~vr,~w_ ~ ~ ~ c17 ' 40 r 0 c,-j I a- 4y /0 e- P e cc/ J - JUSTIFICATION: - ' S l•~C~r-? ~c1'zt ~G ~t..C~'~~'_5' ~ ~G'r~ ~ ~ ~ . c ~ ~ ~ ~L (z, e) I e= c.~;"~'uce . /-Yr~' l.. D -%ej L ; / yu~.✓~ .t..-~ ~1i.5~~~z1 Ci u ~ ~ Il el.ij f~Q~~I~_ , C , ~ C ` ..t~/\ l • ! / ~ `d.6C1LS-C` L.i~' ° ecv" e++,_., ~ e:) L&5'7' LP BY DATE SUBMITTED . ADDRESS --Z 4(-1 c IP CODE 95F262- - ~ i i7 PHONE# -64er?)A ADNIINISTRA.TIVE VARIANCE FEE OF $30•00 PAID TO SPOKANE COUN1'Y 1026 W BROADWAY, SPOKANE WA 99260-0170 PHONE (509)456-3600 FAX (509)324-3478 -REQUEST WII..L NOT BE REVIEWED WITHOUT FUNDS- CASH/CHECK #f RECENED BY DATE 1,\yV\daiga.aev Sl93 RECEIVED J U N 2 8 2000 IJubmittal Checklist tS'r 544. for Road & Drainage Projects in Spokane County - Plats/ShM IMaWUNTY ENGINEER This Submittal Checklist is to be completed arrd signed by the Sponsor's Engineer, and included with each plan subntittal into the Spokarre County Engineers Office. If this form is not fully completed and sigried, do not subrrtit plans und calculations to Spokarre County for review and acceptance. Incorrrplete submittal.s will be returned and will cuuse unnecessary delays for your client. J ~ Pro'ect Name: ~ O &&LA Ie) „f C ~ 04 tl~P ~c~~c Spokane County Project No. T; S~-Kn 'f - gA Date: (o 17- 9,tla0 ~ Project Engineer: . . t CLA-4 < ~ P ~ • Phone: ~ 36 ` 0406 ~ Project Sponsor: 2 v4) ervr -F ~3 na.c.A-c ce MeF Phone: 12 y'1:Lz -3 n A. Preliminary Process Prior to Submittal of Road and Drainage P(ans, the following events are to have already occurred: (By checking each item off shown below, you are stating that you have verified lhese events/items have been completed.) 0~ Adoption of a Hearing Examiner's Report for this long plat, or a Planning Report for this short plat. 0( At least one Pre-Design Meeting has been held with County staff at the Engineers Office. 0 An "Agreement to Pay Fees" has been signed by the project sponsor, and submitted to the County Engineers Office. 0 A Channelization Plan (e.g. signing and striping plan) of public roadway improvements, has been coordinated and discussed with the County Engineers Offce. B. Road and Drainage Plan Submittai The items listed below are to be provided as a minimum with a road and drainage plan submittal. Additional information may be required to demonstrate that the plans meet all applicable standards. (By checking "yes " for each iten: shown below, you are verifying that these items have been completed and are included in this submittal. For a►ty box checked "rt/a", a written justification of any omissions ut the end of this section is requiretl.) 0 yes Road and drainage plans, ttivo print sets. (Certification statement on cover of plans) 0 yes Each Plan Shee# of record is signed and dated by the project sponsor. QYyes The road and drainage design meets the requirements of State law, WAC 196-27 regarding "conformity with accepted standards"; that is, the design reflects the "state of the practice" ~ for the proposed concept. I( yes The plans, Drainage Report, basin map(s), and any other calculations are stamped, signed ~ and dated by an engineer Licensed in the State of Washington. Vyes 0 n/a Drainage Report, two sets. To include: basin map(s), time of concentration routes in basio , map, and Certification statement on cover of report and basin map. Vyes 0 n/a Geotechnical Repart, one set. (include all soil test pit/aoring logs.) L,.t OA(V) fi}lf yes 0 n/a Structural Pavement Calculations, one set 7r 0 yes Re-IV-a Cross-slope grade calculations for road widening projects. y p ~ I 0 yes Vn/a Maintenance Manual and Sinking Fund calculations for drainage facilities located outside of , County road right-of-way. 0 yes Vn/a Written explanation of who/what entity will be responsible for maintaining drainage facilities which are located outside of public road right-of-way, and that thE plan is acceptable to the County Engineers 4ffice. 0 yes en/a Channelization Plan, or signing and striping information provided in the road plans. To be ,r included in road and drainage plan set. ~es &/h/a I have read the Hearing Examiner's Report (long plat), or Planning Dept. Findings and Conditions (short plat), for this project. The design meets the conditions in the report. eyes 0 n/a Copy of Approved Design Deviations. 0 yes Vn/a Fire District Approval, for private roads. 0 yes Vn/a Lot Plans. Required for any lots with drainage easements and which front a public road, or A for lots which receive and treat runofffrom a public right-of-way. 0 yes f~n/a Any applicabie State and Federal permits have been obtained. (i.e. HPA, JARPA, etc.). For Permits with conditions, a copy of the permit and conditions are included in the pla❑ submitta(. U/ yes 0 n~(a Inspection Agreement between the sponsor and its engineer. 0 yes Vn/a For off-site easements to be granted to Spokane County, the foliowing items shall be included: legal description, elchibit, and proof of ownership. 0 yes 0 n/a Erosion Control Plan, required for "Major Land-bisturbing Activity." To be included in the road and drainage plan set. Explanation for any items listed above which are not included in this submittal: (Note: an insufficient justification of why an item was not included in the submitted, or incomplete documents, may resutt in the submittai being returned without review or without acceptance. Provide attachrnents if necessary.) By signing below, the engineer is stating that the information provided in the submittal is complete, that the information provided in the Submittal Checklist is accurate, and the plans and calculations are in accordance with the Spokane County Standards for Road & Sewer Cofistruction, and the Guidelines for Stormwater Management, except where an approved Design Deviation allows otherwise. 0 Engineer's Signatuxe: Date: Co /-Z 9/G o Engineer's Name: (please print) ~ If there are any questions ahout this form or appropriate procedures, please call Developrrxent Services, Spokane County Public Works, at (509) 456-3600. ]For Spokaae Counly Use Only Submittal No: County Plan Reviewer: 0 Accepted in for Review or Construction 0 Returnod to the engineer without review and/or acceptance, See attached letter of explanation. Processing Date: Submittai Checklist 2 Spokane County Public Wor[cs; Apri129, 1998 07/13/2000 THU 14:38 FAX 509 536 0565 TECNCON INC IA001/002 ~ . , ~ .i - . ~ i . ~ . FAx TRANsmissioN . TFCHCort, INC. East 1230 Front Avenue Spokane, WA 99202-2148 Tel: (509)536-0406 FAX: (509)536-6565 I'rom: Ta: ~ X+'AX ~ Pfionc: ~ 2 36 Cn c~ . Date: ?/t G1v Time: Total Pages (includcs cover): ~ llctivcr To: Message: ~"u . ~ JUL-13-2000 15:42 509 536 0565 93% P.01 07/13/2000 THU 14:38 FAX 509 536 0565 TECHCON INC 002/002 ~ s4,,~• ~N ~ - ~ ~ ~ TO SwRI[ 8ET1Y[EM ~ Da. 7' SDE WALK \ ~ , ~ ~egaas t99 6 ~ . ` w/ r[tFJa AwD G• O i `~(49s. ! OON1R41. tArB \ A T ~ UWDSG1PUid q1ST~ GHAN GRASS ►!Et \ E OETML El. El. t ~ wC9T [rq , ~ VAqIMA L•e9 v, a o. ~ 9 CM5 CtuliRX. SEC OESAIL ~ E4. 1997.0 ~F s ~TtA 1 STVB,- TOtAI • 604 SJ, t' ETiR. Wil vAIK ` ~ St 80 TOM ~i9 27 STA 0t64.4lkW8 OT P~ ~ gTA`Or66.4a \ s O"SCT zo~ 1996 H' ~ STA 0461.11 °f ` ctme cvrs (19 o.~ ~a~a s ~ :a~• TCeBC 1497.79 ~ N. OiiStT 23A' ~ SET pfT11~ 17/a DRrwELL Rm El. 1947.77 ~ \ STA t 173.1 56[ OCTAIL 1 Df 4 \ $,-Oi'RSEi 20.5 iBC (T1t9~CAL Oi 2 N. GY~(SEi 20.3 ~i6C; ~ STA 0+67: TOP 01 BUtY EL IWD~Z ~ ~JRS QiTS (Y) ~ BERr BETe~EEN ldr~}A. D ~ . ~4' Lp~ FEST ENO StiM,1l.E ANO a a`, ~ ~rc•w~ 2001.00 UME swALE (rw a z) ase~~---mo-sa-r- ERA ~ 51[kE ` STA i.Ot PMALr NARISe s.s. S. CFr SlT 23.5 . Sl OIIE[T IJ.S ~ 1998 O~t+ 0.. 2001_54 . ~ ~ SE TA7L 15/4 ~ ~ ar ~t) ~ STA 1+81 ~ BEIM eEnJEcn wVgM ~ west e►a syruf .~w ♦ ~UQR!p StdALC (TYP or 2) ES ~ ~ \ 1 ~ GIST'IDtRtl~# ' ~ RoAGS1aE Swl~lE MK AF" 12W S.F. NNI mm MN sm STA P~OE`~SIy~. ~ RA 3~ J~ A9CTTOY.O . 910PE0 OFiS£T 20.9' (iBC S, ~ ~ ~ W a~DE fiwK¢~90Tf~r~ ~ . TC~ @0C 20L07li0 5CC O[1wl 17/4 --.y-._---------- - am-v---°°------°m-~------ea. ~ N. --R- a. zoae.9 soae i • 6 -iEV D EXPIRES 7 , VAiaMA \,3 I AND54CAK ; ~ s F ~ (TV) I I ' ~ ~ I ~ ~0°'• ~ o SEWER EASEMENT RkC. # 9405' •~~'~~~r-~ ..a. o , 1---------4 a €----~___.-p,.---~---~-~----E-- - . ~ 4L _ - - \ - Ap- - - - -1 - ~~~~~~~~m~pmmm~o~~~~~~ ffi►~~av~~aB'ii~~~m~~w - - - - sYa..stm ~ - - - - - - - - - PRO,tFCT BEGINNINC JUL-13-2000 15 :43 509 536 0565 93%, . . . . . . P.02 BOWSTRING METHOD (TEN YEAR STORM DESIGN) PROJECT: BSP 64 DETENTION BASIN DESIGN BASIN: south -E~,'( 7D $MGqON REVIEWER: parry NUMBER OF DRYWELLS PROPOSED DATE: 14-Ju1-00 1 Single (type A) Double (type B) Total Area (calc.) (see H 1) 0.29 Time of Conc. (calc.) (see H1) 5.44 Composite "C" (calc.) (see H1) 0.80 Time of Conc. (min) 5.44 Area (Acres) 0.28650138 C' Factor 0.80 Impenrious Area (sq. ft.) 17200 Volume Provided 208: 1810 storm: 3649 Outflow (cfs) 0.3 Area C" Factor 0.23 #1 #2 #3 #4 #5 #6 #7 Time Time Intensity Q dev. V in V out Storage Inc. Inc. (min.) (sQC.) (in./hr.) (cfs) (cu. ft.) (cu. ft.) (cu. ft.) (#1 *60) (A"C*#3) (Outf.*#2) (#5-#6) 5.44 326.27 3.10 0.71 309 97.88 211 5 300 3.18 0.73 292 90 202 10 600 2.24 0.51 363 180 183 15 900 1.77 0.40 408 270 138 20 1200 1.45 0.33 434 360 74 25 1500 1.21 0.28 445 450 -5 30 1800 1.04 0.24 453 540 -87 35 2100 0.91 0.21 459 630 -171 40 2400 0.82 0.19 470 720 -250 45 2700 0.74 0.17 474 810 -336 50 3000 0.68 0.16 483 900 -417 55 3300 0.64 0.15 498 990 -492 60 3600 0.61 0.14 516 1080 -564 65 3900 0.60 0.14 549 1170 -621 70 4200 0.58 0.13 570 1260 -690 75 4500 0.56 0.13 589 1350 -761 80 4800 0.53 0.12 594 1440 -846 85 5100 0.52 0.12 618 1530 -912 90 5400 0.50 0.11 629 1620 -991 95 5700 0.49 0.11 649 1710 -1061 100 6000 0.48 0.11 669 1800 -1131 DRAINAGE POND CALCULATIONS Required grassy swale pond storage volume = Impervious Area x.5 in./ 12 in./ft. = 717 cu. ft. provided: 1810 cu. ft. OK! DRYWELL REQUIREMENTS - 10 YEAR DESIGN STORM Ma)amum storage required by Bowstring = 211 cu. ft. provided: 3649 cu. ft. OK! Number and type of Drywells Required = 1 Single 0 Double TIME OF CONCENTRATION (minutes) Tc (overland) Tc (gutter) Areas "C" A'C Ct = 0.15 L2 = 500 0.05 0.30 0.014876 Z1 = 3 0.24 0.90 0.2132231 L 1(A) = 116 Z2 = 50 0.00 0.10 0 N(A) = 0.03 B= 0.00 0.00 0 S(A) = 0.01 n= 0.016 0.00 0.00 0 s= 0.03 0.00 0.00 0 Tc (A) = 1.26 d= 0.11 0.00 0.00 0 Total A Com p "C" L1(B) = 60 Tc (gu) = 3.59 0.29 0.80 , N(B) = 0.016 Tc(A+B) = 1.84 S(B) = 0.01 Q=C"I"A= 0.71 Tc(tot.) = 5.44 Q(est.) = 0.74 Tc (B) = 0.6 Intensity = 3.10 A = 0.32065 WP = 5.8490 R = 0.0548 V = 2.32 Tc (total) = Tc (overiand) + Tc (gutter) Tc(gu) = 3.59 Tc (overland) = Ct*(L1 *N/S^0.5)^O.6) Q(est) = 0.74 Ct = 0.15 L1 = Length of Overland Flow Holding = 17.81 N= friction factor of overland flow (.4 for average grass cover) S= average slope of overland flow Tc (gutter) = Length (ft.)Neloc+ty (ft./sec.)/60 B= Bottom width of gutter or ditch Z1 = inverse of cross slope one of ditch ZZ = inverse of cross slope two of ditch d= depth of flow in gutter (estimate, check estimate with Flow) Area = d"B+d"2!2*(Z1+Z2) Wetted perimeter = B*d+(1 /sin(atn(1 /Z1))+1 /sin(atn(1 /Z2))) Hydraulic Radius = R= Area/Wetted Perimeter Velocity = 1.486/n`R".667*s".5 Flow = Velocity'Area n = 0.016 for asphalt s= longitudinal slope of gutter Par , Ed To: alan gay Cc: bill hemmings Subject: BSP64 Alan: I looked over the revised basin map (your eariler e-mail) and tried to correlate it to the drainage calculations. It appears that there are now 2 basins on each of the north and south sides of the road: from station 1+91 ) east to Sullivan, and from 1+91 west to the end of the cul-de-sac (on both the north and south sides of the road, for a total of 4 basins). I still have these questions: 1. Marietta ACP width should be 40' between toe of curb (Engineer Condition #7, Standard Plan #A1). Plans show 40' to gutter flowline. 2. Marietta back-of-curb width would be 42'. Required RNU width is 48' (Engineer Condition #6), or to 3' beyond curbs; plans show R/W of 65'. 3. Remainder of swale & sidewalks should be in a border easement to back of sidewalk. It appears that the strip between the curb and sidewalk should be a minimum of 10', as it is being used for drainage. 4. How do the calculations show that easterly basin provides enough storage volume for the design storm event and enough volume for the 208 treatment requirement (V208 = road area * 1/2fl, swale floor area so V208 is maximum of 6" depth)? Please note that if either the slope of the swales exceeds 1%, or the length of the swale exceeds 100 ft, then the swale volume needs to be adjusted as noted in the Guidelines for Sformwater Management. The width of the swale between the courb and sidewalk 5. Do the plans take into account the fact that the drywell rim needs to be set at least 0.4' below either the invert of a curb inlet or the bank of a berm in order to develop the design flow rate into the drywell (with a safety factor)? This typically results in a floor elevation of 0.9' below the normal gutter line/top of berm for a swale with a drywell in it. What is the top of berm elevation at 1+81? 6. Does any of the area from Sullivan Road drain into the site? The profile grades and plan elevations seem to indicate that some portion of Sullivan drains onto the site. If so, the basin limits need to be adjusted accordingly and shown on the Basin map. 7. Given our conversation of July 13th, it appears that the calculations should be revised so that infiltration is not considered as a disposal mechanism for the swales. Where the location is suitable for drywells, swale storage volume should be based on drywell outflow. I am enclosing a copy of the spreadsheet we use to evaluate drywell concepts. It may be of some use. If the theoretical Tc is less than 5 minutes, then the spreadsheet Tc defaults to 5 minutes to fit the I-D-F cuNe. If there is gutter flow, it will need to be adjusted until the values in cells Q14 and Q15 balance (approximately equal values for these; I wouldn't carry the value of pd" to more than 3 places right of the decimal). I will be out of the office until July 24th. Please contact Bill Hemmings if you have questions about the spreadsheet Ed Page 1 ~ ~ BOWSTR10A97 Page 2 . t ~ - RE^ r-11 f,ED JU t 2000 SPpK,~~E C;vUfv, r tNGIN Drainage Report, R.A. Bonucce- ~i EER Zd 5;4* Marietta at Su----ivan Deve--opment BSP-64-98 Spokane County, Washington Stateme n The following report was prepared under my direction. The contents are engineering opinions derived usi.ng procedures that meet industry and professional standards. This document was not prepared as a construction document. Alan E. Gav Professional Eneineer Printed Narne Title Civil Engineer Julv 11. 2000 Date ~Q- kti" ~ ~r. ?9194 cSS,~~NAL EXP!RES 7°--'/! -J TCCII.CoN, INC. Professional Engineers • Certified Cnvironmental Specialists • Project Nlanagers • Steel Detailers t ) DRAINAGE REPORT ROBERT A. BONUCCELLI MA►1ZIETTA AT SULLIVAN INDUST.RIAL DEVELOPMENT SPOKANE COUNTY, WASHINGTON Proposed improvelnents to the site at the extension of Marietta Road west of Sullivan Road, trigger the need for storrn water runoff disposal improvements by Spokane County regulation. The calculation sheets following this narrative include details of the analysis showing that the proposed drainage improveinents are adequate to control runoff on the site for a 10-year event, and safely discharge runoff for larger events at a rate equivalent to or less than the discharge rate in the pre-developed condition for the site. Key assumptions made for the site include assuming that the soils are Garrison gt-avely loarn and Garrison very stony loam with an effective penneability equal to oi- greater than 0.36 inch per hour (0.36"lh.r.). Another key assumption is that the intensity-duration-fi-equency (IDF) curves for the site conform to the IDF curves for Spokane as published in Chart 34 of the Washington State Department of Transportation (WSDOT) Hydraulics Manual. The drainage areas in the development are designatcd by parcel and roadway. Parcel basins are shown as Parcel 1 through 9, with Parcel 4B being held in reserve. Drainage subinittals f.or Parcels 1 through 9 will be made at the time of application for individual site building pernlits. Parcel 4B may or may not be used for drainage for one or more of Parcels 1 tluough 9. Roadway basins are designated as Marietta West, Marietta Middle and Marietta East. These drainages are shown with these designations on the drainage and grading plans presented with this report, as well as the times of concentration for Marietta West, Marietta Middle and Marietta East. The Bowstring method was used to assure that the roadside swales will have adequate volume to contain a ten year storm event The existing hydrologic conditions for the site are undevEloped. The calculated peak runoff for the existing site, using the SCS mefihod, follows: Q=(P - 0.2S)2 / (P + 0.85), where: Q= runoff in cfs, P= total stonn rainfall, S= potential abstraction in inches S= 1000/CN -10 CN = curve number In this case, the CN = 70, since the soil group is Garrison, an "B" hydrologic soil. The land use is approximately the same as pasture in fair condition, thus the 70 rating. S= 4.29 P= 3.04 inches in 24 hours for a 100 year storm. Q= 0.737 inches over the site. f ~ The site drainage basin is approximately the 19.3 acres of the site, since the drainagc is bounded on the west by the old Cominco property, which slopes to the west, the north edge of the site is the Johnson Matliey property with its own hydrologic controls, the south edge of the site is the old Milwaukee Railroad right-of-way, and drains toward the south, and the east edge is Sullivan Road. Therefore the total pre-developed runoff from a 100 year event is predictcd to bc 620,000 cubic feet. For the peak runoff, the hydraulic length is 1234 feet, which equates to an equivalent area of 19.3 acres. Using the Type II stonn curve, the estimated peak runoff for a CN70 is 11 cfs/in of runoff. This equates to 8.1 cfs allowable peak runoff. For a 10 year storm, P= 2.12, and Q= 0.287 inches over the site; therefore the allowable peak runoff is 3.16 cfs for a 10 year stoi-i11. The predicted peak amount is 0 cfs for the SW and SE basins, unless a runoff-over- ice condition develops that fills over 7000 cubic feet of storage, in which case up to 3 cfs would be discharged thr.ough the overflow pipe in the southwest corner of the SW swale. I . , QVANAGE TRACT \ 103.51' i u \ d / \ si.aaF 3~.i S+OEwaLK ' TO ORA1M TO $WALE BETKEEN ~ ROAOWAY dc SIOEWA,LK ~ 113.26 ' TC 1998 75 \ LEl 1998.25 Cl El. ~ ~ r998.0- i{- - SERMCE ~ 999_6 _ X ^~rE - - -)C- - ~ - " - - - - ~ - _ _ H' n~ aw ~ _ ~85 > >+~iii w/ METER arv0 AttZ QM_ATIC C- 0.024 a• 1998-4 \ CONTROL. lAYOUT -8Y GRASS A ALi LANDSCA'ING INSTALIEk CHANNEI "'-F1M! \ ~E DETAit El. El. 199 6 t 1998.65 ~ wEST EnfO \ MARIEnA \ ~ \ BASIN C=69 lF, G- 0.19 GRASS CwwNEL. SEE OETAtI 5/4 Cl EL KST MARIETTA 1' WA7ER JRVICE El. 1997.0 ~ 1598.14 ~ ROAOSIO SwAIE STUB.- TOTAL AR • 602 S.F. 1' ETER, GATE VALVf \ TYP EA \ SiA9 3 ~ \ \ 80TTOM E 19 , 27 ~ $TA 0t64.4boCilRB PT Su i.~:0 STA~+65.48 L. 1g'~ 3 ` \ S. OfFSET 20.BC) - \ 1996 1 N. OfFSET 20.5 ( C) 1 ~ g~' \ \ CURB CUTS " t„ ~ , v SiA 0+61.11 Ot' LONC ~ ~ ~ ~ S. UFfSET 23.5' ~ \ TC=BC 1997.79 N. OFfS£T 23.5' SEE OETaL 17/4 \ r yi0b0, ORYw~tl Riu El 1997.77 $TA 1+7} 1 SEE 0£TaL 15/4 ~ 5. fSET 20.5 (iBC) ~ Su 1. (TirPtCAL 0F 2) N OffSET 20.5 (TBG) tit• 20 p Y STA 0*67; TOP Of BERM El. 1998.29` ~ 'FURB CUTS (2) BERbA BETM£EN lOt1iER, \ ~ wE57 Ek0 SwnLE /w0 Cl EL. \ TC~200o00 MIDDi.E Swni.E (TYP Of 2) \ oo~c. ~ ~'3 00 0oooo~E.QLTAk;d~~oooc.-~ » - •~``-~oa=oe-r+oooo-- oo- o-c1c.~c2o ` - oooa- mc-- o - --o WiQOIE MARfETTA V. \ ~ 116AII51pE SwAiE a91 Si~ ~ TQTAL AtRE~ 458 S P. STA ' ~ (rrP EacH SIoE) 5. OffSET 23.5' SrA • O~PSEt 23.5' \ o c~~ • nr° c°-o.o3. SLQK° ~ 1998 pRYtoECl1ittU El. 2001 54 SE"EraiL 15/4 ' o STa 1+81 ~ (TYPIQF 2) r ~ BERM BETVlEEN LONfR, ~ A \wE$T ENO $WALE ANO ~ pTA N(pLE SwALE (irP OF 2) \ BJLSIN \ - ~ 3 qCRES ~ ~ $1A \ L. zo STA ? ~ E/~SfA'ARIE7FA ~ ~ L ROA~SiOE SwALE TOTAL aREA 1200 S.F. C \c ' (TYP EACH S10E) 2 10 StA~ y BOTTOM EL. SLOPEO 5 ~ STA 3t 73 3~1\ ?Q AT C=0.03 OffSET 20 5' (T8C) ~ S 2~ ?i .~Oi'FSET 20.5' (TBC) ~ • CURB CUTS {2} \ 3' VnDE SwALE BOTiO~.i,'.-^ ~ O LONC EA ?ao . ♦ (TYP) rca @c 2007.10 ~ s,A : SEE OErai\L t 7/a f2 .o m o ol-c- o 0 o w o c~ w c. m o c~ c-. c- a= o 0 o c~ ~ o c.. - o 0 o a- o c-~ o o m c.~ c o 0 0 0~ o 0 o e-- - o 0 0 0 o r o 0 0 n 1 IVf_ x El 2008,9 CL 2008. El. 1 ~ `3 ~ ~ .6 ( ► • ~ ~ j a EAST EHO ~ \ ~1 \ MAWETTA BAStN ~ LahDSi.ADE S£i'BAOC (TTP) Y Y _ - ~ q u ~ 0 0 o ~ ~ t0O9. a SEWER EASEMENT RL-C. ~ ~ ~ . ,.o ~q o ~f 1 ~ o :6-EL - - 8 T e _>.,9g,F Q 0 G.. - - - - - ~ B g4+190 i~5 1--~----~~ -~---_r_J__~__-~_~----~----Q----E----~-€-- ~ B ~ ETBACK ~ ^ _ _ ~ - - - ~ - - - - _ - - ~ - - _ - r _ - - - - - ^ - - ~ - - - ¢ - - ~ ~~!c - - - - - ~ C7~~'oc~'o~~ ~i-jCAoo~ooooamoaa0 oM naanoC3C:v ~aIoaoaaouoM ooli crrl c'o4= ~!7irac.~iCD 0 Bonuccelli Development Marietta & Sullivan 11-Ju1-00 Stormwater Disposal Entire Site is One Parcel Drain to Individual Parcel 208 swales Areas Required: Resulting Landscaping Area: TOTAL TOTAL NET NET MAX. UNBUILD- MIN LOADING REQ. Sublot # Type III Type IV AREA ACRES AREA ACRES BUILDING ABLE PARKING DOCK AVAIL? SWALE Imp.Area acres 1 2892.5 0 83135 1.908517 80242.5 1,842114 32422.65 44094.76 1800 OK 6158.994 73907.93 1,696693 2 3499 0 229719 5.273623 226220 5.193297 137831.4 0 56235.15 3600 OK 16003.59 192043 4.408702 3 993.6 0 106456 2.443893 105462.4 2.421084 63873.6 26060.4 2700 OK 7502.33 90027.96 2,066758 4 203.1 0 78459 1.801171 78255.9 1.796508 47075.4 19206.74 1800 OK 5513.456 66161.47 1.518858 5 993.6 0 93875 2.155073 92881.4 2.132264 56325 22980.58 1800 OK 6567,293 78807.52 1.809172 6 950 950 94052 2.159137 92152 2.115519 56431.2 23023.91 1800 OK 6579.393 78952.72 1.812505 7 1003.05 1250 50000 1.147842 47746.95 1.096119 20000 27199.97 360 OK 3736.665 44839.98 1,029384 8 700 0 35000 0.903489 34300 0.78742 14000 19039.98 360 OK 2624.665 31495.98 0.723048 9 1973.55 0 38135 0.875459 36161.45 0.830153 14872.65 20226.78 360 OK 2786.396 33436.76 0.767602 ROADWAY 0 0 37708 0.865657 37708 0.865657 0 0 0 NA 3142.333 37708 0.865657 SWSwale; 3255 0 74739 1.715771 71484 1.641047 0 0 0 0 TOTAL: 921278 21.14963 TOTAL; 60615.11 SQ. FT. 15.17952 Engcalc1-E-1 4 7 Banuccelli devePopment hAarietta & Sullivan 11-.lul-00 - Stvrmwa#er Dispasal Bowstring Method CalcuPatvn, Raadside Swaie Capacaty, MarIEtfa Area 1: West End, Mariekta, TYP1CAL EA. SIQE 5wale Area' 602.2942 square feet Volurne; 1997.27 213,7647 1997.52 408.0295 77.72428 cu_fk. 1997.77 602.2942 204 0147 Cu,fk_ Pond Infiltratlan Rate: 0.001781 cfs (0.36'Yhr infiltrakion rate) Dry+rvell Infiltration Rate 0.3 cfs (Garrison Grauelly Ioam) Ne,. of aryvwrells: 'I Qrywell Vfllume: 54.45 cubrc feek Total Available Storage V41ulme: 258.4647 cubic feet Use Brawstring Mekhad tu check adequacy of SwaPe: Time incfement; 2 min. ' Time af Goncentration: 2 min. Storage req.; Oukflaw (C,f.s.) (up (a 0, 0.00 cfs 237.4318 cfi. Design yearflow 30 year 4.16 Acres Imp; C=0_9 Area (acres) 0_1$ DeveJoped C factor; 0.86 0.01 Acres Perv: C=0.4 Area x C 0.15 No. 1 Na. 2 No. 3 No. 4 No. 5 No. 6 No. T Time Inc. t Jntensity Qdev. 1! in 11 out Stvfage No. 1 x 60 (in.lhr) A*C*N o.3 Out * No.2 2 120 3.18 0.479519 57.85831 0.213765 57.65455 a 240 3.18 0.479519 115.4106 0.427529 114.983 s 360 2.9 0.437297 157J242 0_641294 157.0829 5 aso 2,5 0X698 181_2068 0_855059 130.3517 10 600 2,25 0.339282 203.8 1.068824 2023311 15 900 1.76 0.265394 239.035 1.603238 237.4318 20 1200 1.45 0.218648 262.5268 92.13165 170.3892 {ouerflow to dryweEls} Area 2: IVliddle SeGtion, Marietta TYPICAL EA. SIDE Swale Area: 654 square feeY Ilolunne: 2006.5$ 273 2006.83 463.6 92.0625 cu.ft. 2007.58 654 511.125 cu.ft, Once ponci volume is exceeded, then ou#ffvw vver end berm: Pond Infltration Rate; 0.002275 cfs (0.36"ihr infiltration rafe) Drywell Infltration Rafe 0_3 cfs (Garrisan Geavelly loarn) End Berrn "C" 3 (BroadcresteCl 1Neir) End Berm weir equatian: 3*L*H"312 L= 3 feet; H=,1 feet Therefare Vlleie autflaw: 0.284605 cfs Na. of Drywells- 0 I]rywell Volume: 0 cubic feet Total Auailable Storage Volulme; 511.125 cubic feet Use 8owstring Me#hod to check adequacy of Swale: TEme increment; 2 min. Time of Cancen#ration: 2 rnin. Stflrage req,: 4utflow (C.f.s.) 0.00 cfs 511.9285 Cf. Design year flow 10 year 0.107 Acres Imp; C=0.9 Area (acres) 0.122 Devefoped G factor: 0.838395 4.015 Acres Penr: C4,4 Area x C 0.102 Engcalci-E-1 +1 Bonuccelli Development Marietta & Sullivan 11-Ju1-00 Stormwater Disposal No.1 No.2 No.3 No.4 No.5 No.6 No.7 Time Inc. t Intensity Q dev. V in V out Storage No. 1 x 60 (in./hr) A'C"No.3 Out' No.2 2 120 3.18 0.387499 46.76333 0.273 46.49033 4 240 3.18 0.387499 93.26317 0.546 92.71717 6 360 2.9 0.353379 127.4568 0.819 126.6378 8 480 2.5 0.304637 146.433 1.092 145.341 10 600 2.25 0.274174 164.6906 1.365 163.3256 15 900 1.76 0.214465 193.164 2.0475 191.1165 20 1200 1.45 0.17669 212.1477 2.73 209.4177 25 1500 1.22 0.148663 223.0956 3.4125 219.6831 30 1800 1.04 0.126729 228.1986 4.095 224.1036 35 2100 0.92 0.112107 235.4999 4.7775 230.7224 40 2400 0.82 0.099921 239.8784 5.46 234.4184 45 2700 0.75 0.091391 246.8183 6.1425 240.6758 50 3000 0.69 0.08408 252.2968 6.825 245.4718 55 3300 0.64 0.077987 257.4106 7.5075 249.9031 60 3600 0.61 0.074331 267.6439 8.19 259.4539 65 3900 0.60 0.073113 285.1902 8.8725 276.3177 70 4200 0.58 0.070676 296.8866 9.555 287.3316 75 4500 0.55 0.06702 301.6365 10.2375 291.399 80 4800 0.53 0.064583 310.0428 10.92 299.1228 85 5100 0.52 0.062755 320.0946 11.6025 308.4921 90 5400 0.50 0.060927 329.0497 12.285 316.7647 95 5700 0.49 0.059709 340.3814 12.9675 327.4139 100 6000 0.49 0.0591 354.638 13.65 340.988 105 6300 0.45 0.054691 344.5883 14.3325 330.2558 110 6600 0.44 0.053057 350.2121 15.015 335.1971 115 6900 0.42 0.051542 355.6716 15.6975 339.9741 120 7200 0.41 0.050131 360.9786 16.38 344.5986 125 7500 0.40 0.048815 366.1433 17.0625 349.0808 130 7800 0.39 0.047582 371.1751 17.745 353.4301 135 8100 0.38 0.046426 376.0822 18.4275 357.6547 140 8400 0.37 0.045338 380.8723 19.11 361.7623 145 8700 0.36 0.044313 385.5522 19.7925 365.7597 150 9000 0.36 0.043344 390.128 20.475 369.653 155 9300 0.35 0.042428 394.6055 21.1575 373.448 160 9600 0.34 0.041558 398.9897 21.84 377.1497 165 9900 0.33 0.040733 403.2856 22.5225 380.7631 170 10200 0.33 0.039948 407.4975 23.205 384.2925 175 10500 0.32 0.0392 411.6293 23.8875 387.7418 180 10800 0.32 0.038487 415.6849 24.57 391.1149 185 11100 0.31 0.037806 419.6677 25.2525 394.4152 190 11400 0.30 0.037154 423.581 25.935 397.646 195 11700 0.30 0.03653 427.4277 26.6175 400.8102 200 12000 0.29 0.035932 431.2107 27.3 403.9107 205 12300 0.29 0.035358 434.9324 27.9825 406.9499 210 12600 0.29 0.034807 438.5955 28.665 409.9305 215 12900 0.28 0.034277 442.2022 29.3475 412.8547 220 13200 0.28 0.033768 445.7546 30.03 415.7246 225 13500 0.27 0.033276 449.2548 30.7125 418.5423 230 13800 0.27 0.032803 452.7046 31.395 421.3096 235 14100 0.27 0.032346 456.1059 32.0775 424.0284 240 14400 0.26 0.031905 459.4603 32.76 426.7003 245 14700 0.26 0.031479 462.7695 33.4425 429.327 Engcalc1-E-1+2 Bonuccelli Deveaoprnent Marietta & Sullivan 11-,lu1-04 Storrnwater Disposal 250 15000 0.25 0.031068 46fi.0349 34.125 431.9099 255 15300 0_25 4_030869 469_2581 34.8475 434.4506 260 15600 0,25 0.030283 472.4403 35.49 436,9503 265 15900 0.25 0.02991 475.5829 35.1725 439,4904 270 16200 0.24 0,029547 478.687 36.855 441.832 275 16500 024 0.0291196 481.7539 37.5375 444.2164 280 16800 024 0.028855 484.7847 38.22 446.5647 285 17100 (}.23 0.028524 487.7804 38.9425 448.8779 290 17400 0.23 0.028202 490742 39.585 451.157 295 17740 0.23 0.(}2789 493.6706 40,2675 453.4031 300 18000 0.25 0.027586 496.5669 40.95 455.8169 305 18300 0.22 0.02729 499.4-32 41.6325 457.7995 310 18500 022 0.027003 502_2666 42.315 459.9516 315 18900 0.22 0.026722 505.0715 4z.9975 462.074 320 19200 012 a.026449 507.8476 4168 464,1676 325 19540 0.21 0.026983 510.5956 44.3625 466.2331 330 19800 0.21 0.025924 513.3161 45.045 468.2717 335 20100 0.21 0.025671 516.0099 45.7275 470.2824 340 20400 0.21 0.025425 518.6776 46.41 472.2676 345 20700 0.21 0.025184 521.3198 47_0925 474,2273 354 21000 0.20 0.024949 523.9372 47.775 476.1622 355 21300 0.20 U,024719 526.5344 48.4575 478.0729 360 21600 0.20 O.024495 529.0998 49.14 479.9598 365 21900 0.20 0.024275 531.6461 49.8225 481.8238 370 22200 0_20 0.024061 534.1698 50Z05 483.6648 375 22500 0.20 0.023851 536.6113 51,1875 485.4838 380 22800 0.19 O.Q23646 539.1 59 2 51.87 487.2812 385 23104 0.19 0023446 541.6099 52,5525 489.0574 390 2340D 0.19 0.023249 544.0479 53.235 490.8929 395 23700 0.19 0.023057 546.4655 53_9175 492.548 400 24000 0.19 0.022869 548.8633 54.6 494.2633 405 24300 0.19 0e022684 551 ,24-17 55.2825 495.9592 410 24600 0.18 0_022503 553.601 55.965 497.636 415 24900 018 0.022326 555.9416 56,6475 499.2941 420 25200 0.18 0.022153 558.2839 57,33 500.9339 425 25500 0,18 0.021982 560.5882 58.0125 502.5557 430 25800 0.18 0.02181~i 562.855 58.695 504.16 435 26100 0A8 0_021652 555.1244 59_3775 505.7469 440 26400 0.18 0.021491 567.377 60.06 507,317 445 26700 0.48 0.021333 569.6129 60.7425 508,5704 450 27000 0.17 0.027778 571.9325 61.425 510,4075 455 27300 O.17 0.021026 574,036 62.1075 511.9285 460 27600 0.17 0.020877 576.2239 148.1715 428.0524 QverFl4w to UVest Drywvells Area 3: East End, Marie" TYRICAL IEA. SIDE Swale Area: 1200 square feet Vvlume: 1997.27 5(]1 1997.52 850,5 168.9375 c0t, 1997.77 1200 425.25 c0t. Pond Infilkration Rate: 0.004175 cfs (17.36"Ihr infiltration rate) Oryweli Infltration Rate 03 efs (Garrison Gravelly loam) Na. of Drywells. 1 arywell Volume; 54.45 cubic 6ee# Total Available 5tarage Volulme: 479.7 aubic fee# Use Bawstring Mekhod to check adequacy af S+,vale: Er,gcalcl-E-1+3 Bonuccelli Development Marietta 8 Sullivan 11-Ju1-00 Stormwater Disposal Time increment; 2 min. Time of Concentration: 2 min. Storage req.: Outflow (c.f.s.) (up to 0 0.00 cfs 426.7537 cf. Design year flow 10 year 0.116 Acres Imp; C=0.9 Area (acres) 0.143 Developed C factor: 0.804 0.028 Acres Perv: C=0.4 Area x C 0.115 No.1 No.2 No.3 No.4 No.S No.6 No.7 Time Inc. t Intensity Q dev. V in V out Storage No. 1 x 60 (in./hr) A'C*No.3 Out * No.2 2 120 3.18 0.456267 55.06233 0.501 54.56133 4 240 3.18 0.479519 115.4106 1.002 114.4086 6 360 2.9 0.437297 157.7242 1.503 156.2212 8 480 2.5 0.37698 181.2068 2.004 179.2028 10 600 2.25 0.339282 203.8 2.505 201.295 15 900 1.76 0.265394 239.035 3.7575 235.2775 20 1200 1.45 0.218648 262.5268 5.01 257.5168 25 1500 1.22 0.183966 276.0745 6.2625 269.812 30 1800 1.04 0.156824 282.3893 7.515 274.8743 35 2100 0.92 0.138729 291.4245 8.7675 282.657 40 2400 0.82 0.123649 296.8428 10.02 286.8228 45 2700 0.75 0.113094 305.4308 11.2725 294.1583 50 3000 0.69 0.104047 312.2103 12.525 299.6853 55 3300 0.64 0.096507 318.5384 13.7775 304.7609 60 3600 0.61 0.091983 331.2019 15.03 316.1719 65 3900 0.60 0.090475 352.9149 16.2825 336.6324 70 4200 0.58 0.087459 367.3889 17.535 349.8539 75 4500 0.55 0.082936 373.2667 18.7875 354.4792 80 4800 0.53 0.07992 383.6693 20.04 363.6293 85 5100 0.52 0.077658 396.1081 21.2925 374.8156 90 5400 0.50 0.075396 407.1898 22.545 384.6448 95 5700 0.49 0.073888 421.2124 23.7975 397.4149 100 6000 0.49 0.073134 438.8545 25.05 413.8045 105 6300 0.45 0.067678 426.4184 26.3025 400.1159 110 6600 0.44 0.065657 433.3776 27.555 405.8226 115 6900 0.42 0.063781 440.1337 28.8075 411.3262 120 7200 0.41 0.062036 446.7009 30.06 416.6409 125 7500 0.40 0.060407 453.092 31.3125 421.7795 130 7800 0.39 0.058882 459.3187 32.565 426.7537 135 8100 0.38 0.057451 465.3912 123.8175 341.5737 Overflow to Drywell Worst Case Inlet Depression, Type 1 Inlet: 0.1 ft. Flow: 0.48 cfs = Q (use TR55 flow calc where applicable) maximum allowable ponding: 0.33333 feet = h = head for weir of inlet grate Required area of inlets: Cw= 3 Q=Cw"Lh^(3/2) L=Q/(Cw"h"(3/2)) Lmin.= 0.824279 feet Therefore a 4' long inlet will be more than adequate for a 10-year storm event for each curb inlet. Engcalc1-E-1+4 BanucceUi Development Induskrial aeve[vpment at 5ullivan and Mar+et#a 11-Jul-O0 TechCon, Inc. Prepared by Alan E Cay, P-F- Site Hydrology Study aesign to 10 year storm (for review b y Spokane County Engineers)- Use conserva#ive 5 min. intensity i= 3.2 inlhr Disposaf Capacity: Garrison Gravelly LaamlVery Stony LoaTn 5oil Estimated rurF InFiltration Capacity q= 0,36 inJhr - Rato of ifq 8.888889 MaKimurn 5korage Depkh: 6 in, 14 year, one haur intensity: , 3.2 inJhr 10 year, 24 hvur total- 2,12 in. Parcet 1 Drain Basin ToW Improved lmperviaus Surface Area: 73907.93 square feet Asphalt Irnpervious Surface Area~ new• 392$1 5qusre feet Raaf: direct_ 32422.65 square feet Sidewalk; new: 2204.738 square feet lJtNFae biaFilfration swale (grassy) for dispvsal. Assume an[ecedani saturaked soil conditions; lJtilize Spokane Gounty Type A drywefls for averflow. Include storage volurne of drywells as w~!El as dryaaeli anfiltration cap2cily, Auailable Grassy Area: 9227.066 square Feet pepressed Infiltration Area: 6158,994 square fee# cwltivated surface Additional available infiitrakivn volume on side slopes: Perime#er 6° abvve battom 470.8756 square feef additional on slopes Tota1 Available for Infiltration- 6829_87 square fee = 3197.216 ft3 7otal Required Under Caunty Standard: 1636.689 f13 OI{ Hydrology Check: Rational Methad. Peak Runo#F, 10-yea r starrri, Q=CIA Irnpervious SurFace G- 0.9 Pervious Surface G: 0.25 10-year intensily: 3_2 inlhaur Time of concentration. 3.65 min. Area Impervious: 73907.93 square feet Area Pervious: 9227.066 square feet Peak Q: 5.06 c#s Peak Infltration Rate: 0.36 rnfhour Pervious Surface, non-swale: 2591.196 square feet Peak 0, Perv, nan-swale: 0.05 Cfs [nfiltration capacity, Perv, nan swale: 0.02 cFs Engcalci-G-1 Bonuccelli Development Industrial Development at Sullivan and Marietta 11-Ju1-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Sludy Design to 10 year storm (for review by Spokane County Engineers). Peak Q, remainder: 5.03 cfs Swale Infiltration Capacity: 0.0552 cfs drywell infiltration cap.: 0.3 cfs each (1 total) Storage Required, 5 minule Storm: 1403.71 cubic feet Storage Available, Swale Only: 3197.216 cubic feet Plus Drywells: 54.45 cubic feet Total: 3251.67 cubic feet OK Peak Runoff, 50-year storm: (5 minute) 50-year intensity: 5.1 in/hour Peak Q: 8.06 cfs Storage Required: 2394.30 cubic feet Swale Plus Drywell: 3251.67 cubic feet OK Parcel 2 Drain Basin Total Improved Impervious Surface Area: 192043 square feet Asphalt Impervious Surface Area• new: 51400 square feet Roof: direct: 137831.4 square feet Sidewalk• new. 2811.758 square feet Ulilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 37675.96 square feet Depressed Infiltration Area: 16003.59 square feet cultivated surface Additional available infiltration volume on side slopes: Perimeter 6" above bottom 759.0317 square feet additional on slopes Total Available for Infiltration• 16762.62 squar2 fee = 8191.551 ft3 Total Required Under County Standard: 2141.662 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year intensity: 1.95 inlhour Time of concentration: 13 min Area Impervious: 192043 square feet Area Pervious: 37675.96 square feet Peak Q: 8.16 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale: 20913.34 square feet Engcalc1-G-2 Bonuccelli Development Industrial Development at Sullivan and Marietta 11-Ju1-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Peak Q, perv, non-swale: 0.23 cfs Infiltration capacity, perv, non swale: 0.17 cfs Peak Q, remainder: 7.98 cfs Swale Infiltration Capacity: 0.1397 cfs drywell infiltration cap.: 0.3 cfs each (1 total) Storage Required, 13 minute Storm: 5885.06 cubic feet Storage Available, Swale Only: 8191.551 cubic feet , Plus Drywells: 54.45 cubic feet Total. 8246.006 cubic feet OK Peak Runoff, 50-year storm: (13 minute) 50-year intensity: 27 in/hour Peak Q: 11.30 cfs Storage Required: 8751.66 cubic feet Swale Plus Drywell: 8246 006 cubic feet NG Storage Available, 12": 16762.62 cubic feet OK Parcel 3 Drain Basin Total Improved Inmpervious Surface Area: 90027.96 square feet Asphalt Impervious Surface Area: new: 24851 square feet Roof: direct: 63873.6 square feet Sidewalk: new: 1303.02 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 16428.04 square feet Depressed Infiltration Area* 7502.33 square feet cullivated surface Additional available infiltration volume on side slopes- Penmeter 6" above bottom 519.696 square feet addibonal on slopes Total Available for Infiltration: 8022.026 square fee = 3881.089 ft3 Total Required Under County Standard: 1035.473 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year intensity: 3.2 inlhour Time of concentration. 4.6 min. Area Impervious: 90027 96 square feet Area Pervious: 16428.04 square feet Engcalcl-G-3 Bonuccelli Development Industrial Development at Sullivan and Marietta 11-Ju1-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Peak Q: 6.25 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale: 8406.011 square feet Peak Q, perv, non-swale: 0.15 cfs Infiltration capacity, perv, non swale: 0.07 cfs Peak Q, remainder: 6.18 cfs Swale Infiltration Capacity: 0.0669 cfs drywell infiltration cap.: 0.3 cfs each (1 total) Storage Required, 5 minule Storm: 1745.12 cubic feet Storage Available, Swale Only: 3881.089 cubic feet Plus Drywells: 54.45 cubic feet Total: 3935.543 cubic feet OK Peak Runoff, 50-year storm: (5 minute) 50-year intensity: 5.1 in/hour Peak Q: 9.97 cfs Storage Required. 2967.11 cubic feet Swale Plus Drywell. 3935.543 cubic feet OK Parcel 4 Drain Basin Total Improved Impervious Surface Area: 66161.47 square feet Asphalt Impervious Surface Area: new: 18126 square feet Roof: direct: 47075.4 square feet Sidewalk: new: 960.3372 square feet Utilize biofiliration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 12297.53 square feet Depressed Infiltration Area: 5513.456 square feet cultivated surface Additional available mfiltration volume on side slopes: Perimeter 6" above bottom 445.5159 square feet additional on slopes Total Available for Infiltration: 5958.972 square fee = 2868.107 ft3 Total Required Under County Standard: 755.2388 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 Engcalcl-G-4 Bonuccelli Development Induslrial Development at Sullivan and Marieita 11-Ju1-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). 10-year intensity: 2.5 in/hour Time of concentration: 8 min. Area Impervious: 66161.47 square feet Area Pervious: 12297.53 square feet Peak Q: 3.59 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale: 6338.559 square feet Peak Q, perv, non-swale: 0.09 cfs Infillration capacity, perv, non swale: 0.05 cfs Peak Q, remainder: 3.54 cfs Swale Infiltration Capacity: 0.0497 cfs drywell infiltration cap.: 0.3 cfs each (1 total) Storage Required, 8 minute Storm: 1531.87 cubic feet Storage Available, Swale Only: 2868.107 cubic feet Plus Drywells: 54.45 cubic feet Total: 2922.561 cubic feet OK Peak Runoff, 50-year storm: (8 minute) 50-year intensity: 3.65 inlhour Peak Q: 525 cfs Storage Required: 2481.68 cubic feet Swale Plus Drywell: 2922.561 cubic feet OK Parcel 5 Drain Basin Total Improved Imperoious Surface Area: 78807.52 square feet Asphalt Impervious Surface Area: new. 21333 square feet Roof: direct: 56325 square feet Sidewalk: new: 1149 029 square feet Ulilize biofiltraiion swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 15067.48 square feet Depressed Infiltration Area: 6567.293 square feet cultivated surface Additional available infiltration volume on side slopes: Perimeter 6" above bottom 486.233 square feet additional on slopes Total Available for Infiltration: 7053.526 square fee = 3405.205 ft3 Total Required Under County Standard: 888.8954 ft3 OK Hydrology Check: Engcalc1-G-5 Bonuccelli Development Industrial Development at Sullivan and Marietta 11-Jui-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0 25 10-year intensity• 2.6 inlhour Time of concentration: 7.5 min. Area Impervious: 78807.52 square feet Area Pervious• 15067.48 square feet Peak Q: 4.46 cfs Peak Infiltration Rate: 0.36 inlhour Pervious Surface, non-swale: 8013.954 square feet Peak Q, perv, non-swale: 0.12 cfs Infiltration capacity, perv, non swale: 0.07 cfs Peak Q, remainder: 4.39 cfs Swale Infiltration Capacity: 0.0588 cfs drywell infiltration cap.: 0.3 cfs each (1 total) Storage Required, 7.5 minute Storm: 1814 73 cubic feet Storage Available, Swale Only: 3405.205 cubic feet Plus Drywells: 54.45 cubic feet Total: 3459.659 cubic feet OK Peak Runoff, 50-year storm: (7.5 minute) 50-year intensity: 3.8 inlhour Peak Q: 6.52 cfs Storage Required: 2897 59 cubic feet Swale Plus Drywell: 3459.659 cubic feet OK Parcel 6 Drain Basin Total Improved Impervious Surface Area: 78952.72 square feet Asphalt Impervious Surface Area: new: 21370 square feet Roof: direct: 56431.2 square feet Sidewalk: new: 1151.195 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 15099.28 square feet Depressed Infiltration Area: 6579.393 square feet cultivated surface Additional available infiltration volume on side slopes: Perimeter 6" above bottom 486.6807 square feet additional on slopes Total Available for Infiltration: Engcalc1-G-6 Bonuccelli Development Industrial Development at Sullivan and Marietta 11-Ju1-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). 7066.074 square fee = 3411.367 ft3 Total Required Under County Standard: 890.43 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious SurFace C: 0 25 10-year intensity: 2.6 inlhour Time of concentration: 7.5 min. Area Impervious: 78952.72 square feet Area Pervious: 15099.28 square feet Peak Q: 4.47 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale: 8033 21 square feet Peak Q, perv, non-swale: 0.12 cfs Infiltration capacity, perv, non swale: 0.07 cfs Peak Q, remainder• 4.40 cfs Swale Infiltration Capacity: 0.0589 cfs drywell infiltraiion cap.: 0.3 cfs each (1 total) Storage Required, 7.5 minute Storm: 1818.34 cubic feet Storage Available, Swale Only: 3411.367 cubic feet Plus Drywells: 54.45 cubic feet 7ota1: 3465.821 cubic feet OK Peak Runoff, 50-year storm: (7.5 minute) 50-year intensity: 3.8 in/hour Peak Q: 6.53 cfs Storage Required. 2903.03 cubic feei Swale Plus Drywell: 3465.821 cubic feet OK Parcel 7 Drain Basin Total Improved Impervious Surface Area: 44839.98 square feet Asphalt Impervious Surface Area: new: 23480 square feet Roof: direct: 20000 square feet Sidewalk: new: 1359.999 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 5160 024 square feet Depressed Infiltration Area: 3736.665 square feet culkivated surface Engcalcl-G-7 Bonuccelli Development Industrial Development at Sullivan and Marietta 11-Ju1-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers) Additional available infiltration volume on side slopes: Perimeter 6" above bottom 366.7696 square feet additional on slopes Total Available for Infiltration: 4103.434 square fee = 1960.025 ft3 Total Required Under County Standard: 978.3324 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year intensity: 3.2 in/hour Time of concentration: 3 min. Area Impervious: 44839.98 square feet Area Pervious: 5160.024 square feet Peak Q: 3 06 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale. 1056.59 square feet Peak Q, perv, non-swale: 0.02 cfs Infiltration capacity, perv, non swale: 0.01 cfs Peak Q, remainder: 3.05 cfs Swale Infiltration Capacity: 0.0342 cfs drywell infiltration cap.. 0.3 cfs each (1 tolal) Storage Required, 5 minute Storm: 814.92 cubic feet Storage Available, Swale Only: 1960.025 cubic feet Plus Drywells: 54.45 cubic feet Total: 2014.479 cubic feet OK Peak Runoff, 50-year storm: (5 minute) 50-year intensity: 5.1 inlhour Peak Q: 4.88 cfs Storage Required: 1439.70 cubic feet Swale Plus Drywell: 2014.479 cubic feet OK Parcel 8 Drain Basin Total Improved Impervious Surface Area: 31495.98 square feet Asphalt Impervious Surface Area: new: 16544 square feet Roof: direct: 14000 square feet Sidewalk: new: 951.999 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Engcalc1-G-8 Bonuccelli Development Industrial Development at Sullivan and Marietta 11-Ju1-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Available Grassy Area: 3504.017 square feet Depressed Infiltration Area: 2624.665 square feet cultivated surface Additional available infiltration volume on side slopes: Perimeter 6" above bottom 307.3889 square feet additional on slopes Total Available for Infiltration: 2932.054 square fee = 1389.18 ft3 Total Required Under County Standard: 689.3327 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year intensity: 3.2 inlhour Time of concentration• 5 min. Area Impervious: 31495.98 square feet Area Pervious: 3504,017 square feet Peak Q• 2.15 cfs Peak Infiltration Rate: 0.36 inlhour Pervious Surface, non-swale• 571.963 square feet Peak Q, perv, non-swale: 0.01 cfs Infiltration capacity, penr, non swale: 0.00 cfs Peak Q, remainder: 2.14 cfs Swale Infiltration Capacity: 0.0244 cfs drywell infiltration cap.: 0.3 cfs each (1 total) Storage Required, 5 minute Storm: 545.26 cubic feet Storage Available, Swale Only: 1389.18 cubic feet Plus Drywells: 54.45 cubic feet Total: 1443.634 cubic feet OK Peak Runoff, 50-year storm: (5 minute) 50-year intensity: 5.1 in/hour Peak Q- 3.42 cfs Storage Required: 1003.34 cubic feet Swale Plus Drywelt: 1443.634 cubic feet OK Parcel 9 Drain Basin Total Improved Impervious Surface Area: 33436.76 square feet Asphalt Impervious Surface Area: new: 17553 square feet Roof: direct: 14872.65 square feet Sidewalk: Engcalc1-G-9 Bonuccelli Development Industrial Development at Sullivan and Marietta 11-Ju1-00 TechCon, inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). new: 1011.339 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywelts as well as drywell infiltration capacity. Available Grassy Area: 4698.245 square feet Depressed Infiltration Area: 2786.396 square feet cultivated surface Additional available infiltration volume on side slopes: Perimeter 6" above bottom 316.718 square feet additional on slopes Total Available for Infiltration: 3103.114 square fee = 1472.378 ft3 _ Total Required Under County Standard: 731.3653 0 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C- 0.25 10-year intensity: 3.2 in/hour Time of concentration: 5 min. Area Impervious: 33436.76 square feet Area Peroious: 4698.245 square feet Peak Q: 2.30 cfs Peak Infiltration Rate: 0.36 inlhour Pervious Surface, non-swale: 1595.13 square feet Peak Q, perv, non-swale: 0.03 cfs Infiltration capacity, perv, non swale: , 0.01 cfs Peak Q, remainder: 2.28 cfs Swale Infiltration Capacity: 0.0259 cfs drywell infiltration cap.: 0.3 cfs each (1 total) Storage Required, 5 minute Storm: 587.35 cubic feet Storage Available, Swale Only: 1472.378 cubic feet Plus Drywells: 54.45 cubic feet Total. 1526.832 cubic feet OK Peak Runoff, 50-year storm: (5 minute) 50-year intensity: 5.1 inlhour Peak Q: 3.66 cfs Storage Required: 1075.18 cubic feet Swale Plus Drywell: 1526.832 cubic feet OK Roadway Basins: West End, North and South Sides: (Mirror Images) Total Improved Impervious Surface Area: 7030.648 square feet Asphalt Impervious SurFace Area: Engcalcl-G-10 Bonuccelli Development Industrial Development at Sullivan and Marietta 11-Ju1-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). new: 5544.86 square feet Roof: new• 0 square feet Sidewalk: new: 1485.785 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: 1 Drywell necessary Available Grassy Area: 602.2942 square feet Depressed Infiltration Area: 213.7647 square feet cultivated surface Additional available infiltration volume on side slopes: Assume 3:1 slopes 1.5 feet wide strip around depression Swale: 388.5295 square feet: up to 6" available for storage on 3:1 slopes Total Available for InGltration: North: 602.2942 square fee = 170.0123 ft3 Total Required Under County Standard: 231.0359 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Imperoious SurFace C: 09 Pervious Surface C: 0.25 10-year intensity: 32 in/hour Time of concentration: 1 min. Area Impervious: 7030.648 square feet Area Pervious: 602.2942 square feet Peak Q: 0.48 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale: 0 square feet Peak Q, perv, non-swale: 0.00 cfs Infiltration capacity, perv, non swale, 0.00 cfs Peak Q, remainder: 0.48 cfs Swale Infiltration Capacity: 0.0050 cfs Drywell infiltratin cap.: 0.3 cfs Storage Required, 5 minute Storm: 51.26 cubic feet Storage Available, Swale Only: 170.0123 cubic feet Plus Drywell: 54 45 cubic feet Total: 224 4666 cubic feet OK Peak Runoff, 50-year storm: (5 minute) 50-year intensity: 5.1 in/hour Peak Q. 0.76 cfs Storage Required: 136.03 cubic feet OK Roadway Basins: Middle, North and South Sides: (Mirror Images) Engcalcl-G-11 Bonuccelli Development Industrial Development at Sullivan and Marietta 11-Ju1-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Total Improved Impervious Surface Area: 4654 square feet Asphalt Impervious Surface Area: new: 4000 square feet Roof: new: 0 square feet Sidewalk: new: 654 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: no drywell necessary Available Grassy Area: 654 square feet Depressed Infiltration Area: 273 square feet cultivated surface Additional available infiltration volume on side slopes: Assume 3:1 slopes 1.5 feet wide strip around depression Swale: 381 square feet: up to 6" available for storage on 3:1 slopes Total Available for Infiltration: North: 654 square fee = 231.75 ft3 Total Required Under County Standard: 166.6667 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year intensity: 32 in/hour Time of concentration: 1 min. Area Impervious: 4654 square feet Area Peroious: 654 square feet Peak Q: 0.32 cfs Peak Infiltration Rate: 0.36 inlhour Pervious Surface, non-swale. 0 square feet Peak Q, perv, non-swale: 0 00 cfs Infiltration capacity, perv, non swale: 0.00 cfs Peak Q, remainder: 0.32 cfs Swale Infiltration Capacity: 0.0055 cfs Drywell infiltratin cap.: 0 cfs Storage Required, 5 minute Storm: 94.28 cubic feet Storage Available, Swale Only: 231.75 cubic feet Plus Drywell: 0.00 cubic feet Total: 231.75 cubic feet OK Peak Runoff, 50-year storm• (5 minute) 50-year mtensity: 5.1 in/hour Peak Q: 0.51 cfs Storage Required: Engcalcl-G-12 Bonuccelli Development Industrial Development at Sullivan and Marielta 11-Ju1-00 TechCon, Inc_ Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). 151.23 cubic feet OK Roadway Basins: East End, North and South Sides: (Mirror Images) Total Improved Impervious Surface Area: 5050 square feet Asphalt Impervious Surface Area: new: 3850 square feet Roof: new: 0 square feet Sidewalk. new: 1200 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: 1 Drywell , Available Grassy Area: 1200 square feet Depressed Infiltration Area: 501 square feet cultivated surface Additional available infiltration volume on side slopes- Assume 3:1 slopes 1.5 feet wide strip around depression Swale: 699 square feet: up to 6" available for storage on 3:1 slopes Total Available for Infiltration: North: 1200 square fee = 425.25 ft3 Total Required Under County Standard: . 160.4167 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year intensity: 3.2 inlhour Time of concentration: 1 min. Area Impervious: 5050 square feet Area Pervious: 1200 square feet Peak Q: 0.36 cfs Peak Infiltration Rate 0.36 in/hour Pervious Surface, non-swale: 0 square feet Peak Q, perv, non-swale: 0.00 cfs Infiltration capacity, perv, non swale: 0.00 cfs Peak Q, remainder: 0.36 cfs Swale Infiltration Capacity: 0.0100 cfs Drywell infiltratin cap.: 0 cfs Storage Required, 5 minute Storm: 105.14 cubic feet Storage Available, Swale Only: 425.25 cubic feet Plus Drywell: 0.00 cubic feet Total: 425.25 cubic feet OK Peak Runoff, 50-year storm: (5 minute) Engcalc1-G-13 Bonuccelli Development Industrial Development at Sullivan and Marietta 11-Ju1-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Sile Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). 50-year intensity: 5.1 in/hour Peak Q: 0.57 cfs Storage Required: 168.54 cubic feet OK Existing Pre-developed Site Total Improved Impervious Surface Area: 0 square feet Asphalt Impervious Surface Area: new: 0 square feet Roof: new: 0 square feet Sidewalk: new: 0 square feet Available Grassy Area: 921278 square feet Depressed Infiltration Area: 0 square feet cultivated surface Additional available infiltration volume on side slopes: Assume 3-1 slopes 0 feet wide strip around depression Swale: 0 square feet: up to 6" available for storage on 3:1 slopes Total Available for Infiltration: North: 0 square fee = 0 ft3 Total Required Under County Standard: 0 ft3 OK Hydrology Check: Rational Meihod: SCS Method : Peak Runoff, 10-year storm, Q=CIA 24 hour storm Impervious Surface C: 0.9 Tc = 25.26 minutes Pervious Surface C: 0.25 Total Area 21.15 acres 10-year intensity: 0.9 in/hour Time of concentration: 36.2 min. Area Impervious: 0 square feet SCS curve No. 61 Area Pervious: 921278 square feet 10-year 24 hour storm: Peak Q: 4.76 cfs 2 12 inches . SCS Type II Storm Peak Infiltration Rate: 0.36 in/hour SCS 100 Hydrograph Pervious Surface, non-swale: 921278 square feet simulate capacity of drywell as Peak Q, perv, non-swale: 0.75 foo/ diameter orifice (no dryv 4.76 cfs Infiltration capacity, perv, non swale: Capacity is adequate. 7.68 cfs Hydraulic Capacity of Drywell is Peak Q, remainder: 0 cfs 0.00 cfs Peak flow: 0.08 cfs Swale Infiltration Capacity: 0.0000 cfs Engcalc1-G-14 % > S P O Yt .A N E ' o rC O U N T Y - R DNISIOIV OF ENGINEERING AND ROADS A DIVISION OF THE PUBLIC WOFtKS DEAARTMENT William A. Johns, P.E., County Engineer August 1, 2000 Alan Gay, P.E. TechCon 1230 E. Front Ave. Spokane, WA 99202 0 SUBJECT: BSP64 - Sullivan & Marietta Design Deviation - Planting Strip Widt6 Gentlemen: We have processed this request, and the County Engineer has not approved it. I am enclosing a copy of the processed Design Deviation. I am also enclosing the recent plan submittal so that it may be revised to reflect the action on this request. Please call Ed Parry ((509)477-3600) if there are any questions. Sincerely, William A. Johns, P.E. Spokane County Engineer G~~ • . Edw d J. , Jr., P.E. Plan Review Engineer Encl: Design Deviation Plan submittal Cc: Project File Reviewer Sponsor: Bob Bonucelli, P.O. Box 141449, Spokane, WA 99214 1026 W. Broadway Ave. • Spokane, WA 99260-0170 •(509) 477-3600 FAX: (509) 477-7655 (2nd Floor) 477-7478 (3rd Floor) • TDD: (509) 477-7133 1 RECFIv PD Submittal Checklist jUl 1 12040 for Road & Drainage Projects in Spokane County - Plats/%61*t?d,%ts Y ,lNEFR This Szcbmittal Checklist is to be completed and signed by the Sponsor's Engineer, and included with each plan submittal into the Spokane Cou»ry Engineers Office. If this form is not fully completed and signed, do not submit plans and calculations to Spokane County for review and acceptance. Incomplete stcbmittals will be returned and wrll cause unnecessary delays for your client. ProJ'ect Name: 86LretQ462 a + a4..x Spokane County Project No. 4fpx~__n" Date: - Z1W_0A!2_ Project Engineer: CCbd-) Phone: 6 `d4-66c - P _Zo~ ' Project Sponsor: , At r Phone: ~ Z y A. Preliminary Process Prior to Submittal of Road and Drainage Plans, the following events are to have already occurred: (By checking each item off shown below, you are statirrg thatyou have verifred these events/items have been completed.) 0~ Adoptioo of a Hearing Examiner's Report for this long plat, or a Planning Report for this short plat. B` ~ At least one Pre-Design Meeting has been held with County staff at the Engineers Office. L~ An "Agreement to Pay Fees" has been signed by the project sponsor, and submitted to the County ~ Engineers Office. • lr A Channelization Plan (e.g. signing and striping plan) of public roadway improvements, has been coordinated and discussed with the County Engineers Office. B. Road and Drainage Plan Submittal The items listed below are to be provided as a minimum with a road a.nd drainage plan submittal. Additional information may be required to demonstrate that the plans meet all applicable standards. (By checking "yes " jor each item shown below, you are verifying that these items have been completed and are included in this submittal. For any box checked "rt/a a written justifrcatiorr oj any omissions at the end of this section is • required.) ~ Item Description L~ ycs Road and drainage plans, t-vvo print sets. (Certification statement on cover of plans) V s 0 n/aOne set of plans on 24" x 36" mylar media, or CA.D electronic file .DWG or .DXF format s Each Plan Sheet of record is si ed and dated b the ro' ~n y p ~ect sponsor. ryes The road and drainage design meets the requirements of State law, WAC 196-27 regarding "conformity with accepted standards"; that is, the design reflects the "state of the practice" /for the proposed concept. Vyes The plans, Drainage Report, basin map(s), and any other calculations are stamped, signed , and dated by an en~ineer licensed in the Sta.te of Washington. Q` yes 0 n/a Drainage Report, two sets. To include: basin map(s), time of concentration routes in basin map, and Certification statement on cover of report and basin map. -7yes ' s a n/a Geotechnical Report, one set. (Include all soil test pit/boring logs.) . ~ a Structural Pavement Calculations, one set 0 yes n/a Cross-slope Srade calculations for road widening projects. Item Description . 'a;'..•. 0 yes n/a Maintenance Manual and Sinl:ing Fund calculations for drainage facilities Iocated autside of County road right-of-way. 0 yes [~Y n/a Written explanation of who/what entity will be responsible for maintaining drainage facilities which are located outside of public road right-of-way, and that the plan is acceptable to the r County Engineers Office. A` yes 0 nia ~ Channelization Plan, or signing and striping information provided in the road plans. To be included in road and draina.ge plan set. 0 yes ~n/a I have read the Hearing Examiner's Report (long plat), or Planning Dept. Findings and Conditions (short plat), for this project. The design meets the conditions in the report. 0 yes 0 p/a Copy of Approved Design Deviation~' ?(,MN4 0%F WW" l~ AWAV 0 yes it,yr1a Fire District Approval, for private roads. 0 yes n/a Lot Plans. Required for any lots with drainage easements and which front a public road, or / for lots which receive and treat cunoff from a public right-of-way. 0 yes LV n/a Any applicable State and Federal permits have been obta.ined. (i.e. HPA, JARPA, etc.). For Permits with conditions, a cop}► of the permit and conditions are included in the plan ~ submittal. E` yes 0 n/a Inspection Agreement between the sponsor and its engineer. Vyes 0 nla For off-site easements to be granted to Spokane County, the following items shall be included: legal description, exhibit, and proof of ownership. B'yes 0 n/a Erosion Control Plan, required for "Major Land-Disturbing Activity." To be included in the road and drainage plan set. Ex lanation for any items listed above which are not included in tlvs submittal: ,/bV cr d Yv~~`J . 40 ~~'<<~~~~ ~l~is !d F►~. ~v-!Q c~Pc.t'. ~ (Note: an insufficAt justification of why an item was not included in the submitted, or incomplete documents, may result in the submittal being returned without review or witiiout acceptance. Provide attachments if necessary.) By signing below, the engineer is stating that the information provided in the submittal is complete, that the information provided in the Submittal Cheeklist is accurate, and the plans and ealculations are in accordance with the Spokane County Standards for Road & Sewer Construction, and the Guidelines for Stormwater Management, except where an approved Design Deviation allows otherwise. Engineer's Signature: O v Engineer's Name: ~ (please print) If there are any questivns about this form or appropriate procedures, please call Development Services, Spokane County Public Works, at (509) 456-3600. For Spokane County Use Only Submittal No: I County Plan Reviewer: 0 Accepted in for Review or Construction ,k Returned to the engineer without r' ac ptance, See attached letter of explanation. Processing Date: ~~t U~ Submittal Checklist 2 Spokane County Public Works; April 29, 1998 v RECE1vFp . JUL 1 1 2000 SPpKANr CUUNTY ENGINE ER Drainage Report, R.A. Bonucce--i Marietta at Su--livan Development BSP-64-98 Spokane County, Washington . Stateme n The following report was prepared under my direction. The contents are engineering opinions derived using procedures that meet industry and professional standards. This document was not prepared as a construction document. Alan E. Gav Professional Engineer Printed Name Title Civil Enaineer Julv 11. Zooo Date OfFIC1P1 PUQI.iC OOCiSNENT SPOIK ANE COUNTY ENGiUEEH`S QFFICE 0 ~I ~ NAi PRc?,1ECT # w t ~E. $JJUt?TAI. # 2 Qp RET°URN TO COUNTY E►yGiNEER 29194 O~ FClS'Y~2~ s~~~1AL ~CS 7 I~ ~U EXPIRE.CD 7---" , TECHCON, INC. Professional Engineers • Certified Environmental Specialists • Project Managers • Steel lletailers e r DR.AINAGE REPORT ROBERT A. BONUCCELLI MARIET'I'A AT SULLIVAN INDUSTRIAL DEVELOPIVIENT SPOKANE COUNTY, WASHINGTON Proposed improvements to the site at the extension of Marietta Road west of Sullivan Road, trigger the nced for stonn water runoff disposal improvements by Spokane County regulation. The calculation sheets following tllis narrative include details of the analysis showing that the proposed drainage improvements are adequate to control runoff on the site for a 10-year event, and safely discharge runoff for larger events at a rate equivalent to or less than the discharge rate in the pre-developed condition for the site. Key assumptions made for the site include assuming that thc soils are Garrison gc-avely loam and Garrison very stony loam with an effective permeability equal to or greater than 0.36 inch per hour (0.36"/hx.). Another key assumption is that the intensity-duration-frequency (IDF) curves for the site conform to the IDF curves for Spokane as published in Chart 34 of the Washington State Department of 1,ransportation (WSDOT) Hydraulics Manual. The drainage areas in the development are designated by parcel and roadway. I'arcel basins are shown as Parcel 1 through 9, with Parcel 4B being held in reserve. Drainage submittals for Parccls 1 through 9 will be made at the time of application for individual sitc building permits. Parcel 4B inay or may not be used for drainage for one or more of Parcels 1 through 9. Roadway basins are designated as Marietta West, Marietta Middle and Marietta East. These drainages are shown with these designations on the drainage and grading plans presented with this report, as well as the times of concentration for Marietta West, Marietta Middle and Marietta East. The Bowstring method was used to assure that the roadside swales will have adequate volume to contain a ten year stonn event Thc existing hydc-ologic conditions for the site are undeveloped. The calculated peak runoff for the cxisting site, using the SCS method, follows: Q=(P - 0.25)2 / (P + O.SS), where: Q= runoff in cfs, P= total stonn rainfall, S= potential abstraction in inches S= 1000/CN -10 CN = curve number ln this case, the CN = 70, since the soil group is Garrison, an "B" hydrologic soil. The land use is approximately the same as pasture in fair condition, thus the 70 rating. S= 4.29 P= 3.04 inches in 24 hours for a 100 year storni. Q= 0.737 inches over the site. • i The site drainage basin is approximately the 19.3 acres of the site, since the drainage is bounded on the west by the old Cominco property, which slopes to the west, the north edge of the site is the Johnson Mathey property with its own hydrologic controls, the south edge of the site is the old Milwaukee Railroad right-of-way, and drains toward thc south, and the east edge is Sullivan Road. Therefore the total pre-developed runoff from a 100 year event i s predicted to be 620,000 cubic feet. For the peak runoff, the hydraulic length is 1234 feet, which equates to an equivalent area of 19.3 acres. Using the Type II storm curve, the estimated peak runoff for a CN70 is 11 cf.s/in of runoff. This equates to 8.1 cfs allowable peak runoff. For a 10 year stonn, P= 2.12, and Q= 0.287 inches over the site; therefore the allowable peak runoff is 3.16 cfs for a 10 year ston-n. The predicted peak amount is 0 cfs for the SW and SE basins, unless a runoff-over- ice condition develops that fills over 7000 cubic feet of storage, in which case up to 3 cfs would be discharged thl•ough the overflow pipe in the southwest cot-ner of the SW swalc. t ~ ANACE ~ NTRACT sLoPE 34.1~ T~0 ORwN ~ TO SWALf BETWEEN ~ ~ 1 13.2fi ~ ~ ~ RTCO1998.75 SIOEWALK \ f ~C 1998 25 Cl El. j Lt$p 1999.6 w 2" iR ON SERNACE l~ 185 lF ~ 1+77 \ 1 W/ METER ANO AUI QMATIG C~ 0.024 il. 1998.4~ ~ 1 . \ CONTROI. LAYOIfT gY GRA55 ~ a$ ALT ~ 1 1 LANDSCAPINC IkSTALIEfF CMANNEI "~-F1ttJs t \ E Of TAIL El. EL. 199 6 ~ 1998.65 \ MARIETTA ~ L=69 Lf, C 0.029 CRa55 CwwNEt. SEE OETat 5/4 BASW V1EST b MARIETTA 1' WATER RVICE EL. 1997 0Cc48~1 6 \ ROAOSIO ' SWALE STUB. - iOTAL AR • 602 S.F, I' EiER, GATE VAI.vE St • BOTTUM E 19 , 27 e ~ ~ ~ STA 0+64.4'bvCURB PT STA 5 OFf5E1 ~20. +6 ' BC) N. OFFSET 20.5 1996 ~ y,~ \ \ CURB CUTS (~j TA i ~ STA 0t61.11 ~ 04' LONC ~ v~e 1 0 S. OfFSEi 23.5' ~ TC=6C 1997.79 ST~.., ~ N. OFfSET 23.5' SEE OETAlL 17/4 \ ~-~=p6p DRYYY£ll RIM El_ 1997.77 ~ STA t+73, \ SEE OETaIL 15/4 \ s. FvSET zo.s (Tac) ~ ~ sr. •D (rra+cw. ov z) N. OF SET 20.5 (TBCj ~ 20~ .;TA 0+67: TOP pf HERN EL 199$.29` ~ R8 CUTS (2) BERM 8£Tw£EN LOwER, \ O s' IONG wEST EHD SWItIE AND -zt Cl EL \ iC2001.00 LOOOLE SwnLE (TVa Of 2) \ 2004.3 ooPOOSEF,OFTaiL~i/f--ao- o00 .-r,GO- - GO- =e...a.oo-~5~z ~~a.~Q=od.,.~oe ~I ` ~ c •~X' ~ ~ ' ` MLDDLE StA i' 9 STA 1+9s • T07AL ARE~ 156 5 F ~ (TYP EACN SIO£~ \ N ~SET 23 S'~ Si~ ~ Ar G-BOTTOMo.o, EL St O 1998 ORYY+ELIM El. 2001 54 A!}r SEE DETRIL 15/4 JL ~j~C A ~ $TA 1+81 ~ (T~I~AL 0F 2) f-r I ' A ~ ~ \ BERM BETw£EN LOw£R, 0 i~~ 61, " a ~NEST ENO SWALE ANti MIO~E ~ 4\tJ(p`LE SWALE (TYP 0F Y) ~ \ MaRiETTa ~ R E S ~IN ~ St~ . ~ ~ - : - STA ~ ~ L za N-, STA ~ L 20 ~S . E115~1~(ARtEiir4 a 0 ~S~oE Sw~.E TO1ItL aREA 1200 S.F. c `E . (Trn Er+cH sEoE) 2. 'At: BOTTOM El. SLOPEO ~ STA 3+73 3~ AT C=Q.OS S t:• S. o«s£T 2o.s (Tec) TA ~ : N\OffSFT 20.5' (TBC) 3' 1MDE SWAL£ BOTT0M--- CURB CUT5 (2) ~ b rYa \ 0 t' IdNC EA 200, TC~RC 2007.10 Si' i J~ $fE OETAIL 17/4 119 C? e ~ :~~~.a.._.",~o~.aoe.-..~o ~ - - ~.~,voo- oooovoaoo~.ooo.~.moe~.r.om~oo~ o El 2008 9 Cl El ~ 20081 I a 0 0 EaST ENO U \ MARIETTA BASIN ~ LANDSCnvE p ~ ~ t (tra~j ~ ! ~ B ~ m eL. 0 0 ~ 12009. SEWER EASEMENT R~C. ~ ~ ~ f--- 4 .0 i. ~ p L i ~ - - - _ _ _ _ _ 1 ~ O U 0 " y :1- e1 B p- - - - - - - - - -g - - 94 19 01 ~51__~--___~~-___~--.- - - ----~-~--~--~-~----~----p----~_---~_~-- ~ ~ o 0 ZcogtnPr - - - - - - - - _ ETBACK ~ - - - - - - - - - ~ - - _ R- _ - - _ - - - - - ~ - - _ b o - - _ ~a1 ~ o _r.~c~abnc-~r~oooanoc~r~arr~cJ ooo~~ ~oooooaomc1oo~at,4~r~~c~acr~'"~ic~c~~u'oc~II'of-~t~ Bonuccelli Development Marietta & Sullivan 11-Ju1-00 Stormwater Disposal Entire Site is One Parcel Drain to Intlividual Parcel 208 swales Areas Required: Resulting Landscaping Area: TOTAL TOTAL NET NET MAX, UNBUILD- MIN LOADING REQ. Sublot # Type III Type IV AREA ACRES AREA ACRES BUILDING ABLE PARKING DOCK AVAIL? SWALE Imp.Aeea acres 1 2892,5 0 83135 1.908517 80242.5 1.842114 32422.65 44094.76 1800 OK 6158.994 73907.93 1.696693 2 3499 0 229719 5.273623 226220 5.193297 137831.4 0 56235.15 3600 OK 16003.59 192043 4.408702 3 993.6 0 106456 2.443893 105462.4 2.421084 63873.6 26060,4 2700 OK 7502.33 90027.96 2,066758 4 203.1 0 78459 1.801171 78255.9 1.796508 47075.4 19206.74 1800 OK 5513,456 66161.47 1.518858 5 993.6 0 93875 2.155073 92881.4 2,132264 56325 22980.58 1800 OK 6567.293 78807.52 1.809172 6 950 950 94052 2.159137 92152 2.115519 56431.2 23023.91 1800 OK 6579.393 78952.72 1.812505 7 1003.05 1250 50000 1,147842 47746.95 1,096119 20000 27199,97 360 OK 3736,665 44839.98 1,029384 8 100 0 35000 0.803489 34300 0.78742 14000 19039.98 360 OK 2624.665 31495.98 0.723048 9 1973.55 0 38135 0.875459 36161.45 0.830153 14872.65 20226.78 360 OK 2786.396 33436.76 0.767602 ROADWAY 0 0 37708 0.865657 37708 0.865657 0 0 0 NA 3142.333 37708 0.865657 SWSwale: 3255 0 74739 1.715771 71484 1.641047 0 0 a o TOTAL: 921278 21.14963 TOTAL: 60615.11 SQ, FT. 15.17952 Engcalc1-E-1 Bonuccelli Development Marietta & Sullivan 11-Ju1-00 Stormwater Disposal Bowstring Method Calculation, Roadside Swafe Capacity, Marietta Area 1: West End, Marietta, TYPICAL EA. SIDE Swale Area: 602.2942 square feet Volume: 1997.27 213.7647 1997.52 408.0295 77.72428 cu.ft. 1997.77 602.2942 204.0147 cu.ft. Pond Infiltration Rate: 0.001781 cfs (0.36"/hr infiltration rate) Drywell Infiltration Rate 0.3 cfs (Garrison Gravelly loam) No. of Drywells: 1 Drywell Volume: 54.45 cubic feet Total Available Storage Volulme: 258.4647 cubic feet Use Bowstring Method to check adequacy of Swale: Time increment; 2 min. Time of Concentration: 2 min. Storage req.: Outflow (c.f.s.) (up to 0. 0.00 cfs 237.4318 cf. Design year flow 10 year 0.16 Acres Imp; C=0.9 Area (acres) 0.18 Developed C factor: 0.86 0.01 Acres Perv: C=0.4 Area x C 0.15 No.1 No.2 No.3 No.4 No.S No.6 No.7 Time Inc. t Intensity Q dev. V in V out Storage No. 1 x 60 (in./hr) A'C"No.3 Out ' No.2 2 120 3.18 0.479519 57.86831 0.213765 57.65455 4 240 3.18 0.479519 115.4106 0.427529 114.983 6 360 2.9 0.437297 157.7242 0.641294 157.0829 8 480 2.5 0.37698 181.2068 0.855059 180.3517 10 600 2.25 0.339282 203.8 1.068824 202.7311 15 900 1.76 0.265394 239.035 1.603236 237.4318 20 1200 1.45 0.218648 262.5268 92.13765 170.3892 (overflo4v to drywells) Area 2: Middle Section, Marietta TYPICAL EA. SIDE Swale Area: 654 square feet Volume: 2006.58 273 2006.83 463.5 92.0625 cu.ft. 2007.58 654 511.125 cu.ft. Once pond volume is exceeded, then outflow over end berm: Pond Infiltration Rate: 0.002275 cfs (0.36"/hr infiltration rate) Drywell Infiltration Rate 0.3 cfs (Garrison Gravelly loam) End Berm "C" 3 (Broadcrested Weir) End Berm weir equation: 3'L'H^3/2 L= 3 feet; H=.1 feet Therefore Weir outflow: 0.284605 cfs No. of Drywells: 0 Drywell Volume: 0 cubic feet Total Available Storage Volulme: 511.125 cubic feet Use Bowstring Method to check adequacy of Swale: . Time increment; 2 min. Time of Concentration: 2 min. Storage req.: Outflow (c.f.s.) 0.00 cfs 511.9285 cf. Design year flow 10 year 0.107 Acres Imp; C=0.9 Area (acres) 0.122 Developed C factor: 0.838395 0.015 Acres Perv: C=0.4 Area x C 0.102 Engcalcl-E-1+1 Bonuccelli Development Marietta & Sullivan 11-Ju1-00 Stormwater Disposal No.1 No.2 No.3 No.4 No.S No.6 No.7 Time Inc. t Intensity Q dev. V in V out Storage No. 1 x 60 (inJhr) A"'C'No.3 Out " No.2 2 120 3.18 0.387499 46.76333 0.273 46.49033 4 240 3.18 0.387499 93.26317 0.546 92.71717 6 360 2.9 0.353379 127.4568 0.819 126.6378 8 480 2.5 0.304637 146.433 1.092 145.341 10 600 2.25 0.274174 164.6906 1.365 163.3256 15 900 1.76 0.214465 193.164 2.0475 191.1165 20 1200 1.45 0.17669 212.1477 2.73 209.4177 25 1500 1.22 0.148663 223.0956 3.4125 219.6831 30 1800 1.04 0.126729 228.1986 4.095 224.1036 35 2100 0.92 0.112107 235.4999 4.7775 230.7224 40 2400 0.82 0.099921 239.8784 5.46 234.4184 45 2700 0.75 0.091391 246.8183 6.1425 240.6758 50 3000 0.69 0.08408 252.2968 6.825 245.4718 55 3300 0.64 0.077987 257.4106 7.5075 249.9031 60 3600 0.61 0.074331 267.6439 8.19 259.4539 65 3900 0.60 0.073113 285.1902 8.8725 276.3177 70 4200 0.58 0.070676 296.8866 9.555 287.3316 75 4500 0.55 0.06702 301.6365 10.2375 291.399 80 4800 0.53 0.064583 310.0428 10.92 299.1228 85 5100 0.52 0.062755 320.0946 11.6025 308.4921 90 5400 0.50 0.060927 329.0497 12285 316.7647 95 5700 0.49 0.059709 340.3814 12.9675 327.4139 100 6000 0.49 0.0591 354.638 13.65 340.988 105 6300 0.45 0.054691 344.5883 14.3325 330.2558 110 6600 0.44 0.053057 350.2121 15.015 335.1971 115 6900 0.42 0.051542 355.6716 15.6975 339.9741 120 7200 0.41 0.050131 360.9786 16.38 344.5986 125 7500 0.40 0.048815 366.1433 17.0625 349.0808 130 7800 0.39 0.047582 371.1751 17.745 353.4301 135 8100 0.38 0.046426 376.0822 18.4275 357.6547 140 8400 0.37 0.045338 380.8723 19.11 361.7623 145 8700 0.36 0.044313 385.5522 19.7925 365.7597 150 9000 0.36 0.043344 390.128 20.475 369.653 155 9300 0.35 0.042428 394.6055 21.1575 373.448 160 9600 0.34 0.041558 398.9897 21.84 377.1497 165 9900 0.33 0.040733 403.2856 22.5225 380.7631 170 10200 0.33 0.039948 407.4975 23.205 384.2925 175 10500 0.32 0.0392 411.6293 23.8875 387.7418 180 10800 0.32 0.038487 415.6849 24.57 391.1149 185 11100 0.31 0.037806 419.6677 25.2525 394.4152 190 11400 0.30 0.037154 423.581 25.935 397.646 195 11700 0.30 0.03653 427.4277 26.6175 400.8102 200 12000 0.29 0.035932 431.2107 27.3 403.9107 205 12300 0.29 0.035358 434.9324 27.9825 406.9499 210 12600 0.29 0.034807 438.5955 28.665 409.9305 215 12900 0.28 0.034277 442.2022 29.3475 412.8547 220 13200 0.28 0.033768 445.7546 30.03 415.7246 225 13500 0.27 0.033276 449.2548 30.7125 418.5423 230 13800 0.27 0.032803 452.7046 31.395 421.3096 235 14100 0.27 0.032346 456.1059 32.0775 424.0284 240 14400 0.26 0.031905 459.4603 32.76 426.7003 245 14700 0.26 0.031479 462.7695 33.4425 429.327 Engcalcl-E-1+2 Bonuccelli Development Marietta 8 Sullivan 11-Ju1-00 Stormwater Disposal 250 15000 0.25 0.031068 466.0349 34.125 431.9099 255 15300 0.25 0.030669 469.2581 34.8075 434.4506 260 15600 0.25 0.030283 472.4403 35.49 436.9503 265 15900 0.25 0.02991 475.5829 36.1725 439.4104 270 16200 0.24 0.029547 478.687 36.855 441.832 275 16500 0.24 0.029196 481.7539 37.5375 444.2164 280 16800 024 0.028855 484.7847 38.22 446.5647 285 17100 0.23 0.028524 487.7804 38.9025 448.8779 290 17400 0.23 0.028202 490.742 39.585 451.157 295 17700 0.23 0.02789 493.6706 40.2675 453.4031 300 18000 0.23 0.027586 496.5669 40.95 455.6169 305 18300 0.22 0.02729 499.432 41.6325 457.7995 310 18600 0.22 0.027003 502.2666 42.315 459.9516 315 18900 0.22 0.026722 505.0715 42.9975 462.074 320 19200 0.22 0.026449 507.8476 43.68 464.1676 325 19500 0.21 0.026183 510.5956 44.3625 466.2331 330 19800 0.21 0.025924 513.3161 45.045 468.2711 335 20100 0.21 0.025671 516.0099 45.7275 470.2824 340 20400 0.21 0.025425 518.6776 46.41 472.2676 345 20700 0.21 0.025184 521.3198 47.0925 474.2273 350 21000 0.20 0.024949 523.9372 47.775 476.1622 355 21300 0.20 0.024719 526.5304 48.4575 478.0729 360 21600 0.20 0.024495 529.0998 49.14 479.9598 365 21900 0.20 0.024275 531.6461 49.8225 481.8236 370 22200 0.20 0.024061 534.1698 50.505 483.6648 375 22500 0.20 0.023851 536.6713 51.1875 485.4838 380 22800 0.19 0.023646 539.1512 51.87 487.2812 385 23100 0.19 0.023446 541.6099 52.5525 489.0574 390 23400 0.19 0.023249 544.0479 53.235 490.8129 395 23700 0.19 0.023057 546.4655 53.9175 492.548 400 24000 0.19 0.022869 548.8633 54.6 494.2633 405 24300 0.19 0.022684 551.2417 55.2825 495.9592 410 24600 0.18 0.022503 553.601 55.965 497.636 415 24900 0.18 0.022326 555.9416 56.6475 499.2941 420 25200 0.18 0.022153 558.2639 57.33 500.9339 425 25500 0.18 0.021982 560.5682 58.0125 502.5557 430 25800 0.18 0.021816 562.855 58.695 504.16 435 26100 0.18 0.021652 565.1244 59.3775 505.7469 440 26400 0.18 0.021491 567.377 60.06 507.317 445 26700 0.18 0.021333 569.6129 60.7425 508.8704 450 27000 0.17 0.021178 571.8325 61.425 510.4075 455 27300 0.17 0.021026 574.036 62.1075 511.9285 460 27600 0.17 0.020877 576.2239 148.1715 428.0524 Overflow to West Drywells Area 3: East End, Marietta TYPICAL EA. SIDE Swale Area: 1200 square feet Volume: 1997.27 501 1997.52 854.5 168.9375 cu.ft. 1997.77 1200 425.25 cu.ft. Pond Infiltration Rate: 0.004175 cfs (0.36"/hr infiltration rate) Drywell Infiltration Rate 0.3 cfs (Garrison Gravelly loam) No. of Drywells: 1 Drywell Volume: 54.45 cubic feet Total Available Storage Volulme: 479.7 cubic feet Use Bowstring Method to check adequacy of Swale: Engcalc1-E-1+3 Bonuccelli Development Marietta & Sullivan 11-Ju1-00 Stormwater Disposal Time increment; 2 min. Time of Concentration: 2 min. Storage req.: OutFlow (c.f.s.) (up to 0 0.00 cfs 426.7537 cf. Design year flow 10 year 0.116 Acres Imp; C=0.9 Area (acres) 0.143 Developed C factor: 0.804 0.028 Acres Perv: C=0.4 Area x C 0.115 No.1 No.2 No.3 No.4 No.S No.6 No.7 Time Inc. t Intensity Q dev. V in V out Storage No. 1 x 60 (in./hr) A'C'No.3 Out' No.2 2 120 3.18 0.456267 55.06233 0.501 54.56133 4 240 3.18 0.479519 115.4106 1.002 114.4086 6 360 2.9 0.437297 157.7242 1.503 156.2212 8 480 2.5 0.37698 181.2068 2.004 179.2028 10 600 2.25 0.339282 203.8 2.505 201.295 15 900 1.76 0.265394 239.035 3.7575 235.2775 20 1200 1.45 0.218648 262.5268 5.01 257.5168 25 1500 1.22 0.183966 276.0745 6.2625 269.812 30 1800 1.04 0.156824 282.3893 7.515 274.8743 35 2100 0.92 0.138729 291.4245 8.7675 282.657 40 2400 0.82 0.123649 296.8428 10.02 286.8228 45 2700 0.75 0.113094 305.4308 11.2725 294.1583 50 3000 0.69 0.104047 312.2103 12.525 299.6853 55 3300 0.64 0.096507 318.5384 13.7775 304.7609 60 3600 0.61 0.091983 331.2019 15.03 316.1719 65 3900 0.60 0.090475 352.9149 16.2825 336.6324 70 4200 0.58 0.087459 367.3889 17.535 349.8539 75 4500 0.55 0.082936 373.2667 18.7875 354.4792 80 4800 0.53 0.07992 383.6693 20.04 363.6293 85 5100 0.52 0.077658 396.1081 21.2925 374.8156 90 5400 0.50 0.075396 407.1898 22.545 384.6448 95 5700 0.49 0.073888 421.2124 23.7975 397.4149 100 6000 0.49 0.073134 438.8545 25.05 413.8045 105 6300 0.45 0.067678 426.4184 26.3025 400.1159 110 6600 0.44 0.065657 433.3776 27.555 405.8226 115 6900 0.42 0.063781 440.1337 28.8075 411.3262 120 7200 0.41 0.062036 446.7009 30.06 416.6409 125 7500 0.40 0.060407 453.092 31.3125 421.7795 130 7800 0.39 0.058882 459.3187 32.565 426.7537 135 8100 0.38 0.057451 465.3912 123.8175 341.5737 Overftow to Drywell Worst Case Inlet Depression, Type 1 Inlet: 0.1 ft. Flow: 0.48 cfs = Q (use TR55 flow calc where applicable) maximum allowable ponding: 0.33333 feet = h = head for weir of inlet grate Required area of inlets: Cw= 3 Q=Cw*Lh^(3/2) L=Q/(Cw'h^(3/2)) Lmin.= 0.824279 feet Therefore a 4' long inlet will be more than adequate for a 10-year storm event for each curb inlet. Engcalcl-E-1+4 Bonuccelli Developmenl Industrial Development at Suliivan and Marietta 11-J u I-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Use conservative 5 min. intensity i= 3.2 in/hr Disposal Capacity: Garrison Gravelly LoamNery Stony Loam Soil Estimated Turf Infiltration Capacity q= 0.36 in/hr Ratio of i/q 8.888889 Maximum Storage Depth: 6 in. 10 year, one hour intensity: 3.2 in/hr 10 year, 24 hour total: 2.12 in. Parcel 1 Drain Basin Total Improved Impervious Surface Area: 73907.93 square feet Asphalt Impervious Surface Area: new: 39281 square feet Roof: direct: 32422.65 square feet Sidewalk: new: 2204.738 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 9227 066 square feet Depressed Infiltration Area: 6158.994 square feet cultivated surface Additional available infiltration volume on side slopes: Perimeter 6" above bottom 470.8756 square feet additional on slopes 1"otal Available for Infiltration: 6629.87 square fee = 3197.216 ft3 Total Required Under County Standard: 1636.689 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Sur(ace C: 0.25 10-year intensity: 3.2 in/hour Time of concentration: 3.65 min. Area Impervious: 73907.93 square feet Area Pervious: 9227.066 square feet Peak Q: 5.06 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale: 2597.196 square feet Peak Q, perv, non-swale: 0.05 cfs Infiltration capacity, perv, non swale: 0.02 cfs Engcalc1-G-1 Bonuccelli Development Industrial Development at Sullivan and Marietta 11-Ju1-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Peak Q, remainder: 5.03 cfs Swale Infiltration Capacity: 0.0552 cfs drywell infiltration cap.: 0.3 cfs each (1 total) Storage Required, 5 minute Storm: 1403.71 cubic feet Storage Available, Swale Only: 3197.216 cubic feet Plus Drywells: 54.45 cubic feet Total: 3251.67 cubic feet OK Peak Runoff, 50-year storm: (5 minute) 50-year intensity: 5.1 in/hour Peak Q. 8.06 cfs Storage Required: 2394.30 cubic feet Swale Plus Drywell: 3251.67 cubic feet OK Parcel 2 Drain Basin Total Improved Impervious Surface Area: 192043 square feet Asphalt Impervious Surface Area: new: 51400 square feet Roof: direct: 137831.4 square feet Sidewalk: new: 2811.758 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 37675.96 square feet Depressed Infiltration Area: 16003.59 square feet cultivated surface Additional available infiltration volume on side slopes: Perimeter 6" above bottom 759.0317 square feet additional on slopes Total Available for Infiltration: 16762.62 square fee = 8191.551 0 Total Required Under County Standard: 2141.662 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious SurFace C: 0.9 Pervious Surface C: 0.25 10-year intensity: 1.95 inlhour Time of concentration: 13 min. Area Impervious: 192043 square feet Area Pervious: 37675.96 square feet Peak Q: 8.16 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale: 20913.34 square feet Engcalc 1-G-2 Bonuccelli Development Industrial Development at Sullivan and Marietta 11-Ju1-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Peak Q, perv, non-swale: 0.23 cfs Infiltration capacity, perv, non swale: 0.17 cfs Peak Q, remainder: 7.98 cfs Swale Infiltration Capacity- 0.1397 cfs drywell infiltration cap.: 0.3 cfs each (1 total) Storage Required, 13 minute Storm: 5885.06 cubic feet Storage Available, Swale Only: 8191.551 cubic feet Plus Drywells: 54.45 cubic feet Total: 8246.006 cubic feet OK Peak Runoff, 50-year storm: (13 minute) 50-year intensity: 2.7 in/hour Peak Q: 11.30 cfs Storage Required: 8751.66 cubic feet Swale Ptus Drywell. 8246.006 cubic feet NG Storage Available, 12": 16762.62 cubic feet OK Parcel 3 Drain Basin Total Improved Impervious Surface Area: 90027.96 square feet Asphalt Impervious Surface Area: new: 24851 square feet Roof. direct: 63873.6 square feet Sidewalk: new: 1303.02 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions. Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 16428.04 square feet Depressed Infiltration Area: 7502.33 square feet cultivated surFace Additional available infiltration volume on side slopes: Perimeter 6" above bottom 519.696 square feet additional on slopes Total Available for Infiltration: 8022.026 square fee = 3881.089 ft3 Total Required Under County Standard: 1035.473 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year intensity: 3.2 in/hour Time of concentration: 4.6 min. Area Impervious: 90027.96 square feet Area Pervious: 16428.04 square feet Engcalcl-G-3 Bonuccelli Development Industrial Development at Sullivan and Marietta 11-Ju1-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers) Peak Q: 6.25 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale: 8406.011 square feet Peak Q, perv, non-swale: 0.15 cfs Infiltration capacily, perv, non swale: 0.07 cfs Peak Q, remainder: 6.18 cfs Swale Infiltration Capacity: 0.0669 cfs drywell infiltration cap.: 0.3 cis each (1 total) Storage Required, 5 minute Storm: 1745.12 cubic feet Storage Available, Swale Only: 3881.089 cubic feet Plus Drywells: 54.45 cubic feet Total: 3935.543 cubic feet OK Peak Runoff, 50-year storm: (5 minute) 50-year intensity: 5.1 inlhour Peak Q: 9.97 cfs Storage Required: 2967.11 cubic feet Swale Plus Drywell: 3935.543 cubic feet OK Parcel 4 Drain Basin Total Improved Impervious Surface Area: 66161.47 square feet Asphalt Impervious Surface Area: new: 18126 square feet Roof: direct. 47075.4 square feet Sidewalk: new: 960.3372 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 12297.53 square feet Depressed Infiltration Area- 5513.456 square feet cultivated surface Additional available infiltration volume on side slopes: Perimeter 6" above bottom 445.5159 square feet additional on slopes Total Available for Infiltration: 5958.972 square fee = 2868.107 ft3 Total Required Under County Standard: 755.2388 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 Engcalc1-G4 Bonuccelli Development Industrial Development at Sullivan and Marietta 11-Ju1-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). 10-year intensity: 2.5 in/hour Time of concentration: 8 min. Area Impervious: 66161.47 square feet Area Pervious: 12297.53 square feet Peak Q: 3.59 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale: 6338.559 square feet Peak Q, perv, non-swale: 0 09 cfs Infiltration capacity, perv, non swale: 0.05 cfs Peak Q, remainder: 3.54 cfs Swale Infiltration Capacity: 0.0497 cfs drywell infiltration cap.: 0.3 cfs each (1 total) Storage Required, 8 minute Storm, 1531.87 cubic (eet Storage Available, Swale Only. 2868.107 cubic feet Plus Drywells: 54.45 cubic feet Total: 2922.561 cubic feet OK Peak Runoff, 50-year storm: (8 minute) 50-year intensity: 3.65 in/hour Peak Q: 5 25 cfs Storage Required: 2481.68 cubic feet Swale Plus Drywell: 2922.561 cubic feet OK Parcel 5 Drain Basin Total Improved Impervious Surface Area: 78807.52 square feet Asphalt Impervious Surface Area: new: 21333 square feet Roof: direct. 56325 square feet Sidewalk. new: 1149.029 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil condilions: Utilize Spokane County Type A drywetls for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 15067.48 square feet Depressed Infiltration Area: 6567.293 square feet cultivated surface Additional available infiltration volume on side slopes: Perimeter 6" above botiom 486.233 square feel additional on slopes Total Available for Infiltration: 7053.526 square fee = 3405.205 ft3 Total Required Under County Standard: 888.8954 ft3 OK Hydrology Check: Engcalc1-G-5 Bonuccelli Development Industrial Development at Sullivan and Marietta 11-J u1-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year intensity: 2.6 inlhour Time of concentration: 7.5 min. Area fmpervious: 78807.52 square feet Area Pervious: 15067.48 square feet Peak Q: 4.46 cfs Peak Infiltration Rate: 0 36 inlhour Pervious Surface, non-swale: 8013.954 square feet Peak Q, perv, non-swale: 0.12 cfs Infiltration capacity, perv, non swale• 0.07 cfs Peak Q, remainder: 4.39 cfs Swale Infiltration Capacity: 0.0588 cfs drywell infiltration cap.: 0.3 cfs each (1 total) Storage Required, 7.5 minute Storm: 1814.73 cubic feet Storage Available, Swale Only: 3405.205 cubic feei Plus Drywells: 54 45 cubic feet Total: 3459.659 cubic feet OK Peak Runoff, 50-year storm: (7.5 minute) 50-year intensity: 3.8 inlhour Peak Q• 6.52 cfs Storage Required: 2897.59 cubic feet Swale Plus Drywell: 3459.659 cubic feet OK Parcel 6 Drain Basin Total Improved Impervious Surface Area: 78952.72 square feet Asphalt Impervious Surface Area: new: 21370 square feet Roof: direct: 56431.2 square feet Sidewalk: new: 1151.195 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 15099.28 square feet Depressed Infiltration Area: 6579.393 square feet cullivated surface Additional available infiltration volume on side slopes: Perimeter 6" above bottom 486.6807 square feet additional on slopes Total Available for Infiltration: Engcalc1-G-6 Bonuccelli Development Industrial Development at Sullivan and Marietta 11-Ju1-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Siudy Design to 10 year storm (for review by Spokane County Engineers). 7066.074 square fee = 3411.367 ft3 Total Required Under County Standard: 890.43 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year intensity: 2.6 inlhour Time of concentration: 7.5 min. Area Impervious: 78952.72 square feet Area Pervious: 15099.28 square feet Peak Q. 4.47 cfs Peak Infiltration Rate: 0.36 inlhour Pervious Surface, non-swale: 8033.21 square feet Peak Q, perv, non-swale- 0.12 cfs Infiltration capacity, perv, non swale: 0.07 cfs Peak Q, remainder: 4.40 cfs Swale Infiltration Capacity: 0.0589 cfs drywell infiltration cap.: 0.3 cfs each (1 total) Storage Required, 7.5 minute Storm: 1818.34 cubic feet Storage Available, Swale Only• 3411.367 cubic feet Plus Drywells: 54.45 cubic feet Total: 3465.821 cubic feet OK Peak Runoff, 50-year storm: (7.5 minute) 50-year intensity' 38 in/hour Peak Q: 6.53 cfs Storage Required: 2903.03 cubic feet Swale Plus Drywell: 3465.821 cubic feet OK Parcel 7 Drain Basin Total Improved Impervious Surface Area: 44839.98 square feet Asphalt Impervious Surface Area. new: 23480 square feet Roof: direct: 20000 square feet Sidewalk: new: 1359.999 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for over(low. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 5160.024 square feet Depressed Infiltration Area: 3736.665 square feet cultivated surface Engcalcl-G-7 Bonuccelli Development Industrial Development at Sullivan and Marietta , 11-Ju1-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Additional available infiltration volume on side slopes: Perimeter 6" above bottom 366.7696 square feet additional on slopes Total Available for Infiltration- 4103.434 square fee = 1960.025 ft3 Total Required Under County Standard: 978.3324 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year intensity. 3.2 in/hour Time of concentration: 3 min. Area Impervious: 44839.98 square feet Area Peroious: 5160 024 square feet Peak Q: 3.06 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale: 1056.59 square feet Peak Q, perv, non-swale: 0.02 cfs Infiltration capacity, perv, non swale: 0.01 cfs Peak Q, remainder: 3.05 cfs Swale Infiltration Capacity: 0.0342 cfs drywell infiltration cap.: 0.3 cfs each (1 total) Storage Required, 5 minute Storm: 814.92 cubic feet Storage Available, Swale Only: 1960.025 cubic feet Plus Drywells: 54.45 cubic feet Total: 2014 479 cubic feet OK Peak Runoff, 50-year storm: (5 minute) 50-year intensity: 5.1 inlhour Peak Q: 4.88 cfs Storage Required: 1439.70 cubic feet Swale Plus Drywell: 2014.479 cubic feet OK Parcel 8 Drain Basin Total Improved Impervious Surface Area: 31495.98 square feet Asphalt Impervious Surface Area: new: 16544 square feet Roof: direct: 14000 square feet Sidewalk: new. 951.999 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Engcalc1-G-8 Bonuccelli Development Industrial Development at Sullivan and Marietta 11-Ju1-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Available Grassy Area. 3504.017 square feet Depressed Infiltration Area- 2624.665 square feet cultivated surface Additional available infillration volume on side slopes: Perimeter 6" above bottom 307.3889 square feet additional on slopes Total Available for Infiltration: 2932 054 square fee = 1389.18 ft3 7otal Required Under County Standard: 689.3327 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year intensity: 3.2 in/hour Time of concentration: 5 min. Area Impervious: 31495.98 square feet Area Pervious: 3504.017 square feet Peak Q: 2.15 cfs Peak Infiltration Rate. 0.36 inlhour Pervious Surface, non-swale: 571.963 square feet Peak Q, perv, non-swale: 0.01 cfs Infiltration capacity, perv, non swale: 0.00 cfs Peak Q, remainder: 2.14 cfs Swale Infiltration Capacity: 0.0244 cfs drywell infiltration cap.: 0.3 cfs each (1 total) Storage Required, 5 minute Storm: 545.26 cubic feet Storage Available, Swale Only: 1389.18 cubic feet Plus Drywells: 54.45 cubic feet Total: 1443.634 cubic feet OK Peak Runoff, 50-year storm: (5 minute) 50-year intensity: 5.1 inlhour Peak Q• 3.42 cfs Storage Required: 1003.34 cubic feet Swale Plus Drywell• 1443.634 cubic feet OK Parcel 9 Drain Basin Total Improved Impervious SurFace Area: 33436.76 square feet Asphalt Impervious Surface Area: new: 17553 square feet Roof: direct: 14872.65 square feet Sidewalk: Engcalc1-G-9 Bonuccelli Development Industrial Development at Sullivan and Marietta 11-Ju1-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). new: 1011.339 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 4698.245 square feet Depressed Infiltration Area: 2786.396 square feet cultivated surface Additional available infiltration volume on side slopes: Perimeter 6" above bottom 316 718 square feet additional on slopes Total Available for Infiltration: 3103.114 square fee = 1472.378 ft3 Total Required Under County Standard: 731.3653 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year intensity. 3.2 in/hour Time of concentration: 5 min. Area Impervious: 33436.76 square feet Area Pervious: 4698.245 square feet Peak Q. 2.30 cfs Peak Infiltration Rate: 0.36 inlhour Pervious Surface, non-swale: 1595.13 square feet Peak Q, perv, non-swale: 0.03 cfs Infiltration capacity, perv, non swale: 0.01 cfs Peak Q, remainder: 2.28 cfs Swale Infiltration Capacity: 0.0259 cfs drywell infiltration cap.: 0.3 cfs each (1 total) Storage Required, 5 minute Storm: 587.35 cubic feet Storage Available, Swale Only: I 1472.378 cubic feet , Plus Drywells• 54.45 cubic feet Total: 1526.832 cubic feet OK Peak Runoff, 50-year storm: (5 minute) 50-year intensity: 5.1 in/hour Peak Q: 3.66 cfs Storage Required: 1075.18 cubic feet Swale Plus Drywell: 1526.832 cubic feet OK Roadway Basins: West End, North and South Sides: (Mirror Images) Total Improved Impervious Surface Area: 7030.648 square feet Asphalt Impervious Surface Area: Engcalcl-G-10 Bonuccelli Development Industrial Development at Sullivan and Marietta 11-Ju1-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). new: 5544.86 square feet Roof: new: 0 square feet Sidewalk: new. 1485.785 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant salurated soil conditions: 1 Drywell necessary Available Grassy Area: 602 2942 square feet Depressed Infiltration Area: 213.7647 square feet cultivated surFace Additional available infiltration volume on side slopes: Assume 3:1 slopes 1.5 feet wide strip around depression Swale: 388.5295 square feet: up to 6" available for storage on 3•1 slopes Total Available for Infdtration: North: 602.2942 square fee = 170.0123 ft3 Total Required Under County Standard: 231.0359 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year intensity: 3.2 in/hour Time of concentration: 1 min Area Impervious: 7030.648 square feet Area Pervious: 602 2942 square feet Peak Q. 0.48 cfs Peak Infiltration Rate: 0 36 inlhour Pervious SurFace, non-swale: 0 square feet Peak Q, perv, non-swale: 0.00 cfs Infiltration capacity, perv, non swale: 0.00 cfs Peak Q, remainder: 0.48 cfs Swale Infiltration Capacity: 0.0050 cfs Drywell infiltratin cap.: 0.3 cfs Storage Required, 5 minute Storm: 51.26 cubic feet Storage Available, Swale Only: 170.0123 cubic feet Plus Drywell: 54.45 cubic feet Total: 224.4666 cubic feet OK Peak Runoff, 50-year storm: (5 minute) 50-year intensity: 5.1 in/hour Peak Q: 0.76 cfs Storage Required: 136.03 cubic feet OK Roadway Baslns: Middle, North and South Sides: (Mirror Images) Engcalc1-G-11 . a Bonuccelli Development Industrial Development at Sullivan and Marietta 11-Ju1-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Total Improved Impervious Surface Area: 4654 square feet Asphalt Impervious Surface Area: new: 4000 square feet Roof: new: 0 square feet Sidewalk: new: 654 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: no drywell necessary Available Grassy Area: 654 square feet Depressed Infiltration Area: 273 square feet cultivated surface Additional available infiltration volume on side slopes- Assume 3.1 slopes 1.5 feet wide stnp around depression Swale: 381 square feet: up to 6" available for storage on 3:1 slopes Total Available for Infiltration: North: 654 square fee = 231.75 ft3 Total Required Under County Standard: 166.6667 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year intensity: 3.2 in/hour Time of concentration: 1 min. Area Impervious: 4654 square feet Area Pervious: 654 square feet Peak Q: 0.32 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale. 0 square feet Peak Q, perv, non-swale: 0.00 cfs Infiltration capacity, pero, non swale: 0.00 cfs Peak Q, remainder: 0.32 cfs Swale Infdtration Capacity: 0.0055 cfs Drywell infiltratin cap.: 0 cfs Storage Required, 5 minute Storm: 94.28 cubic feet Storage Available, Swale Only: 231.75 cubic feet Plus Drywell: 0.00 cubic feet Total: 231.75 cubic feet OK Peak Runoff, 50-year storm: (5 minute) 50-year intensity: 5.1 in/hour Peak Q: 0.51 cfs Storage Required: Engcalcl-G-12 , Bonuccelli Development Industrial Development at Sullivan and Marietta 11-Ju1-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). 751.23 cubic feet OK Raadway Basins: East End, North and South Sides: (Mirror Images) Total Improved Impervious Surface Area: 5050 square feet Asphalt Impervious Surface Area: new: 3850 square feet Roof: new: 0 square feet Sidewalk: new: 1200 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: 1 Drywell Available Grassy Area: 1200 square feet Depressed Infiliration Area: 501 square feet cultivated surface Additional available infiltration volume on side slopes: Assume 3:1 slopes 1.5 feet wide strip around depression Swale: 699 square feet: up to 6" available for storage on 3:1 slopes Total Available for Infiltration. North: 1200 square fee = 425.25 ft3 Total Required Under County Standard: 160.4167 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year intensity: 3.2 inlhour Time of concentration: 1 min. Area Impervious: 5050 square feet Area Pervious: 1200 square feet Peak Q: 0.36 cfs Peak Infillration Rate- 0.36 in/hour Pervious Surface, non-swale: 0 square feet Peak Q, perv, non-swale: 0.00 cfs Infiltration capacity, perv, non swale: 0.00 cfs Peak Q, rernainder: 0.36 cis Swale Infiltration Capacity: 00100 cfs Drywell infiltratin cap.: 0 cfs Storage Required, 5 minute Storm: 105.14 cubic feet Storage Available, Swale Only: 42525 cubic feet Plus Drywell: 0.00 cubic feet Total: 425 25 cubic feet OK Peak Runoff, 50-year storm: (5 minute) Engcalcl-G-13 Bonuccelli Development Industrial Development at Sullivan and Marietta 11-J u1-00 TechCon, Inc Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). 50-year intensity: 5.1 in/hour Peak Q: 0.57 cfs Storage Required: 168.54 cubic feet OK Existing Pre-developed Site Total Improved Impervious Surface Area: 0 square feet Asphalt Impervious Surface Area: new: 0 square feet Roof: new: 0 square feet Sidewalk: new: 0 square feet Available Grassy Area: 921278 square feet Depressed Infiltration Area: 0 square feet cultivated surface Additional available infiltration volume on side slopes: Assume 3:1 slopes 0 feet wide strip around depression Swale: 0 square feet: up to 6" available for storage on 3:1 slopes Total Available for Infiltration: North: 0 square fee = 0 ft3 Total Required Under County Standard: 0 ft3 OK Hydrology Check: Rational Method: SCS Method : Peak Runoff, 10-year storm, Q=CIA 24 hour storm Impervious Surface C: 0.9 Tc = 25.26 minutes Pervious Surface C: 0.25 Total Area 21.15 acres 10-year intensity: 0.9 inlhour Time of concentration: 36.2 min. Area Impervious: 0 square feet SCS curve No. 61 Area Pervious: 921278 square feet 10-year 24 hour storm: Peak Q: 4.76 cfs 2.12 inches SCS Type II Storm Peak Infiltration Rate: 0.36 in/hour SCS 100 Hydrograph Pervious Surface, non-swale: 921278 square feet simulate capacity of drywell as Peak Q, perv, non-swale: 0.75 foot diameter orifice (no dryv 4.76 cfs Infiltration capacity, perv, non swale: Capacity is adequate. 7.68 cfs Hydraulic Capacity of Drywell is Peak Q, remainder: 0 cfs 0.00 cfs Peak flow: 0.08 cfs Swale Infiltration Capacity: 0.0000 cfs Engcalcl-G-14 BOWS7RING METHOD (TEN YEAR STORM DESIGN) PROJECT. BSP-64 TIME OF CONCENTRATION iminutes) DETENTION BASIN DESIGN BASIN: Middle 200' REVIEWER, Bill Hemmings, PE Tc (overland) Tc (gutter) Areas C. A'C NUMBER OF DRYWELLS PROPOSED DATE. 04-Aug•00 ~ 1 I Single (type A)l ~Double (type B) Ct = 0 15 L2 = 200 0.02 0,30 0.00729 Total Area (calc.) (see H1I 0.09 Z1 = 3.03 0,06 0,90 0.05832 Time of Cona (calc.) Isee H1) 5.00 U(A) = 20 Z2 = 50 0,00 0.10 0 Composite 'C' (calc.) isee H1) 0.74 NJA) = 0.15 B= 0 0.00 0.00 0 Time of Cona (min) 5.00 SIAI = 0.02 n= 0.016 0,00 0.00 0 Area (Acres) 0.0891 s= 0.03 0.00 0.00 0 C' Factor 0.74 Tc (A) = 0.94 d= 4.07 0.00 0.00 0 Impervious Area isq. ft.) ~ 28251 Total A Comp "C" Volume Provided 208:1 1801 storm:I 180l L1(B) = Tc (gu) = 1.94 0.09 0.74 Outilow (cfs) 0.3 N(B) = Tc(A+B) = 0.94 Area'C"Factor 0.07 S(B) = Q=C'I'A= 0.21 Tc(tot.) = 5.00 Qfest.) ~ 0.22 Itt k2 It3 #4 N5 a6 tl7 Tc (B) = 0.0 Intensity = 3.18 Time Time Intensity 0 dev, V in V out Storage A= 0.1299235 Inc. Inc. WP = 3.7241 (min.) (sea) (in.lhr.) (cfs) (cu. ft.) (cu. ft.) (cu. ft.) R= 0.0349 (k1460) (A'C'#3) (Outf,'q2) (a5•#6) V = 1J2 Tc(total) =Tc(overland) +Tc(gutter) Tc(gu) = 1.94 5.00 300.40 3.18 0.21 64 90.00 -6 Tc(overland) = Ct'(L1•N1S'0.5)"0.6f Q(est) = 0.22 Ct = 0.15 5 300 3.18 0.11 64 90 •6 Ll = Length of Overland Flow Halding = 7.13 10 600 2.24 0.15 103 180 -77 N= friction factor of overland flow (.4 for average grass cover) 15 900 1.77 0.12 116 270 -154 S= average slope of overland flow 20 1200 1.45 0.10 124 360 •236 Tc (gutter) = Length (ft,IlVelocity (ftJsec.)160 25 1500 1.21 0.08 127 450 -323 B= Bottom width of gutter or ditch ~ 30 1800 1.04 0.07 130 540 •410 Zl = inverse of cross slope one of ditch 35 2100 0.91 0.06 131 630 •499 Z2 = inverse of crose elopa two of ditch ` 44 2400 0.82 0.05 135 720 •585 d= depth of flow in gutter (estimate, check eetimate with Flow) ~ 45 2700 0.74 0.05 136 810 -614 Area = d'B+d'212"(21+Z2) 50 3000 0.68 0.44 138 900 •762 VJetted perimeter = B'd+(llsin(atn(llZ1))+1lsin(atn(1JZ2))) 55 3300 0.64 0.04 143 990 •847 Hydraulic Radius R- Area/VJetted Perimeter 60 3600 0.61 0.44 148 1080 •932 Velocity = 1.4861n"R'.667's'.5 1 65 3900 0.60 0.04 158 1170 -1012 Flow = Velocity'Area 0 70 4200 0.58 0.04 164 1260 -1096 n= 0.016 for asphalt 75 4500 0.58 0.04 189 1350 •1181 s= longitudinal slope of gutter 80 4800 0.53 0.03 170 1440 •1270 65 5100 0.52 0.03 177 1530 -1353 90 5400 0.50 0.03 180 1620 • 1440 95 5700 0.49 0.03 187 1710 -1523 106 6000 0.48 0.03 192 1800 •1608 DRAINAGE POND CALCULATIONS Required grassy swale pond storage volume = Imperviaus Area x,5 in,l 12 in,lft. = 118 cu. ft. f~ A t ~ provided: 180 cu. ft, OK! ORYWELI REQUIFEMENTS • 10 YEAR DESIGN STORM Maximum 3toragc rcquircd by Bowntnng = 0 cu, ft. provided: 180 cu. ft. OK! Number and type of Drywells Requved = 1 Single 0 Dauble ~ ~ ~ BOWSTRING METHOD (TEN YEAfl STORM DESIGN) PROJECT: BSP-64 TIME OF CONCENTRATION (minutes) DETENTION BASIN DESIGN BASIN: East 200' REVIEWER: &II Hemmings, PE Tc (overland) Tc (gutter) Aroas C. A'C NUMBER OF DRYWELIS PROPOSED DATE: 04•Aug•00 ~ 11 Single (type A) ~ ~Double (type B) Ct = 0.15 l2 = 200 0.05 0.30 0.01377 Total Area (calc.) (see H1) 0.17 Z1 = 3.03 0.12 0.90 0.108 Time of Conc. (calc.) (see H1) 5.00 L1(A) = 20 22 = 50 0.00 0.10 0 Composite "C" (calc.) (see H1) 0.73 N(A) = 0.15 B= 0 4.00 0,00 0 Time of Conc. Imml 5.00 S(A) = 0.02 n= 0.016 0.00 0.00 0 Area (Acres) 0.1659 s= 0.03 0.00 0.00 0 C' Factar 0.73 Tc (A) = 0.94 d= 0.086 0.00 0.00 0 Impervious Area (sq, ft.) ~ 5300 Total A Comp 'C' Volume Provided 208:1 360 starm:~ 3601 L1(B) = Tc (gul = 1.89 0.17 0.73 Outflow IcfsM 0.3 N(B) = Tc(A+B) = 0.94 Area " C" Factar 0.12 S(B) = Q=C"I•A= 0.39 Tcitot.) = 5.00 Q(est.) = 0.39 Itl k2 tl3 k4 li5 tt6 q7 Tc (B) = 0.0 Intensity = 3.18 Time Time Intansity Q dev. V in V out Storage A= 4.1961049 Inc. Inc. WP = 4.5753 (min.) (sec.) (in./hr.) (cfs) (cu, ft.) (cu. ft.) (cu. ft.) R = 0.0429 (M1'60) (A•C'#3) (Outf.'#2) (N5-#8) V = 1.91 = = Tc(total) =Tc(overland)+Tc(gutter) Tc(gu) = 1.69 5.00 300.00 3.16 0.39 156 90.00 66 Tc (overland) = Ct'(Ll'NIS'0.5)"0.6) Q(est) = 0.39 Ct = 0.15 5 300 3.18 0.39 156 90 66 Lt = Length of Overland Flow Holding = 7.13 10 600 2.24 0.27 191 180 11 N= fncUon factor of overland flow 1.4 (or average grass cover) 15 900 1.77 0,22 216 270 •54 S= average slope of ovarland flow 20 1200 1.45 0.16 234 360 -130 Tc (gutter) = Length (ft.)lVelocity (ft.lsec.)!60 25 1500 1.21 0.15 236 450 •214 B= Bottom width of gutter or ditch 30 1800 1.04 0.13 241 540 -299 Z1 = inverse of cross slope one of ditch 35 2100 0.91 0.11 244 630 -386 22 = inverse of cross slope two of ditch 40 2460 0.82 0,10 250 720 •470 d= depth of flow in gutter (estimate, check estimate with Flow) 45 2700 0.74 0,09 252 810 •558 Area = d'B+d"212'(Z1+Z2) 50 3000 0.68 0.08 257 900 -643 UJetted perimeter = B'd+(ilsiniatni1lZ1))+11sin(atn(11Z2))) 55 3300 0.64 0.08 265 990 •725 Hydraulic Radius = R= ArealWetted Perimeter 60 3600 0.61 0.07 275 1080 •805 Velocity = 1.4861n'R'.667's'.5 65 3900 0.60 0.07 292 1174 •878 Flow = Velocity'Area 70 4200 0.56 0.07 304 1280 •956 n= 0,016 for asphalt 75 4500 0.56 0A7 314 1350 •1036 s= longitudinal slope of gutter 80 4800 0.53 0.06 316 1440 -1124 85 5100 0.52 0.06 329 1530 •1201 90 5400 0.50 0.06 335 1620 -1285 95 5700 0.49 0.06 346 1710 •1364 100 6000 0.48 0.06 357 1800 -1443 DRAINAGE POND CALCULATIONS Required grassy swala pond storage volume = Impervious Area x.5 in,! 12 in,lft. = 221 cu. ft. provided: 360 cu. ft. OK! DRYWEII REQUIREMENTS • 10 YEAR DESIGN STORM Maximum storage required by Bowsiring = 88 cu. ft. provided: 360 eu, ft. OK! Number and type of Drywells Required = 1 Singla 0 Double . 08/04/2000 FRI 11:36 FAX 509 536 0565 TECHCON INC 100011004 ~ . . _ , - RECEev 3 AUG 0 4 20 FAx TIMNSMISSION SROKANE CDUNTY ENC_ NEER TECHCON, INC. East 1230 Front Avenue Spokane, V'VA 99202-2148 Tel: (509)536-0406 FAX: (509)536-0565 From: Alan E. Gav1 P.E. To: )Ed Perrv. P.E. ~ FA►X ( )477-7655 Phone: ( ) 477-3600 . Aatc: A►ugast 4. 2000 Time: Total Pagcs (tnctudcs cover): 4 Deliver To: Message: Following are the revised calculations showing the available voiumcs for ``208" disposal, rcvised for che berm volume and 3% slope. Due to the 10 foot width, even with the 3% slopc the net 208 volume is more than sufficient to meet Spokane County Requircmcnts for each affected basin. Alan Gay AUG-04-2000 12:40 509 536 0565 93% P.01 08/04/2000 FRI 11:36 FAX 509 536 0565 TECHCON INC 10002/004 Bonucoelfi Devefopment ' Industrial pevetopment at Sullivan and Marietta ' 04-Aug-00 , TechCon, Inc. Prepared by Alsn E. Gey, P. E. ; Site Nydrofogy Study r, ; D • Design for 10 year storm (for review by Spokarte Gaunty Engineers). t' er^ Roadway Basirt9: West Enrl, North anii 5outh Sidss: (Mirror tmaqes) 0 p, 't ?QQD Total improved Impervious Surface Area: 7031.8T6 square feet CrJUNTY ENGINEER AsQhatt tmpervious Sucfaoe Area: ~ new: 5159.04 square feet Rcof: rtew: 0 squene feet Sitiewelk: nev,r: 1872.837 square teet Utilize biofltreuon svvale (grassy) for disposai. Assume antecedant saturated soji c:anditicrs: 1 Dlywell necessety Availabte Grassy Ares: 654.2942 square feet Qepressed Infiftration Area: 293.7647 squere feet cultiveted surfaCe Additionat availabte infiltration valume on side stopas: Assume 3:1 slopes 1.5 feet wide strip around depression Swate: 440.5298 square faet up to 6" avnitable for storage on 3:1 stopes Total available for InSitration: North Side: 654.2942 square tee = 217.0147 ft3 Total Require0 undeT covnty standard: 214.96 ft3 OK Hydrofogy Check: Rational Method: Peak Rccrtofi, 10-year stomt, Q=CIA Impervious Surfaoe C: 0.9 Penrious Surtace C: 0.25 10.yeer intensity: 3.2 1Nhour , Time of Concentratian: 1 min. Anea Impenrtous: 7031.876 square feet Area Penrious: 654.2942 square feet Peak Q: 0.48 Cf8 Peak Inf+ltration Rete: 0.36 in/hour Pervious Suriaoe, non-swale: 0.00 square feet Peak Q, perv, Ron-awale: 0.00 cfs infiltration capacity, perv, non-,sw2tle: 0-Ofl cIs • Peek Q, remainder: 0.48 Cfs Swele Infiltr&ii0n Capaaty: ' 0.0055 cfs Oryvrell Infiltretion c8p.: 0.3 efs Srorage Required, 5 minute Stonn: 51.44 cubic feet Storage AvaiEable, Swale Only: 217.0147 ft3 Plub Drywell: 54.45 cubic fest Total: 271.46 cubic feet OK Peak Runofi, 50-year stotm; (5 minute) 60-yeat intensiry: 5.1 in/hovr Peak Q: 0.76 cfs Starage Required, 5 minute Storm: 136.40 OK Roactwar Basins: Middle, North and South Sidea: (Mlrror tmages) Engcslcl•G-18 AUG-04-2000 12:41 509 536 0565 93% P.02 y'(04/2000 FRI 11:36 FAx 509 536 4585 TECHCON INC f6003/004 Bonuc:celti Devetopment ' ~ Industrial Dsvelopment at Sullivan and Marietta 04-Aug-oo _ 7echCon, Inc. . Prspared by Alan E. Gay, P. E. Site Hydrofogy Study Design for 10 Year storm (for review by Spokans Counry Engineers). Total Improved Impervious Surfece Area: RECEOVED 4854 squere feet 4 2000 Asphak Impervious Surfeoe Area: ' Av G Q new: 3700.00 square feet Roaf: SPOKANE COUNTY ENGINEER new: 0 squane feet Sfdewafk: new: . 954 square feet ' Utilize biofittrat;on swale (grassy) tor drsposal. Assume antecedant saturated soil conditions: 1 Dryvreti necessery , Availabie Grassy Area ' 1090 square feet . • Qepressed tnfiltration Areas: There ate a series of 8 bermed area on each side at a 3% slope, Esch bermed area is a total ot 18_16667 tee3 lOng, with the betm 8ocounting for 6 linear feet each. 7neretore tne available infitVation area will be tr8pezoidel in shape, with 10 foot wide tower end, a 12.16667 long CQntrdl seCtion, a verticat rise of 0.545 feet along the length of each erea, and a resutting top eRd uridth pf 4.55 it wlth a net length of 16.53167 feet gnd e resutfing vofume of 43.7474a wbic feet per bermed anea. The area avaitabte tor (nf,ttration wiil be: '10 feet wide at the battcm end, 4.55 feet wide &t the tap end, and 16_53167 fQet Iong, for an area of 120.26788 square feet Total Avaitable !or Infiftration: _ Vofume: North Side: 721.6073 square feet 282.4846 cubic teet Tvtat Required under courrty standard: 154.1667 ft3 OK HydroJogy Chedc: Rationat Method: Peak RuROff, 10-year storm, Q=CJA Impervious Surface C: 0.9 Peroious Surtace C: 0.25 10-year intensity: 3.2 infiour Tirre Of COnCentrdtion: 1 min. • Area lmpervious: 4654 Squaf+e feet Acea Pervious: 1090 square feet Peak Q: 0.33 cfs Peak Infiitration Rate: 0.36 in/hour Pervious Surtace, rton-swale: 0.00 squere feet Peak Q, perv, non-swale: 0.00 cfs Infiltretion capaCity, p8cv, RpR-sWal@: 0.00 cfs Peak Q, remainder. 0.33 CfS Swale Intiltration Capacity: 0.0060 cfa Dryvrel) Infiltretion cap.: 0.3 cfs Storege Required, 5 minute Storm: 6.51 cuOic feet Stocage Availsble, Swa{e Only: 262.4646 ft3 Pius DtyweU' 54.45 cubic feet TotaL 316_93 cubic feet OK Peak Runoff, 50-year storm: (5 minut,e) 50-year intensity: 5.1 iNltour Peak Q: 0.52 ofs Storage Required, 5 minute Storm: sa_8s oK • Engcalcl-G-28 AUG-04-2000 12=41 509 536 0565 93% P.03 V8/09/2000 FRI 11:97 FA$ 509 536 0565 TECHCON INC 044/004 , • Bonucxelli Development ' . . . industrial Developmeni at Sullivan ana nnarietta 04-Au8-00 TechCon, inc. REC EIVED Prepared by Aian E. Gay, P.E. , Site Hydrology Study Design far 10 year storm (for review by Spokane Couniy Engineefs). QuG 0 4 2000 Roadwey 8asins: Enst End, North and South Sidea: (Mtrror lmages) SPOKANE COUNTY ENGINEER Totat lmproved lmperviaus Surface Area: 3450 squarefeet Aspflalt Imperviaus Surface Area: new: 3561 squ8re feet RooY rtewr. 0 square feet Sidewelk: new: 1488.75 square feet . utitize biofiltration swale (grassy) fardisposal. Assume aMecedaM satureted soa conditions: 1 Drywell necessary Aveileble Gressy Area: 2000 square feet Oepressed Infittretian Areas: There ara a series of 12 bemted area on each side at a 3% stope, Each bermed area is e totat of 16.66867 feet long, with thE berm accQUniing (or 6 linear feet esch. Therefore Ure avaitable infi"on area will be trapezoidat in shape, with 10 ~ foot wide lower ertd, a 10.66fi87 lon8 central section, a vertical rise of 0.5 feet along ` ~ the length af each area, and a resulting top end width of 5 ft with 8 net tength of 15.16667 fieet and a resulfing volume of 42.65625 cubic feet per bemned area. 5 . The ares available for intiEuatfon w71 be: 10 feet wide at the bottom end, 5 feet wide at the top eRd, snd 15.96667 feet long, for an area of 113.75 square feet Totai Availa0le tor tniiltration: Volume: North Side: 1365 Squar6 feet 511.875 CubiC feet ~ Total Required unCet oounty sbndatd: 148.375 ft3 aK ~ •7 ol ~ Hydrotagy Chedc: . Ratianal Method. Peaic Runoff, 14-year starm, Q=ClA tmpenricus Surtace C: 0.9 ~ Peryious Sucraoe C: 0.28 ~ 10-year intensity: 3.2 in/hour Time ot Gonaentration: 1 min. Area lmpesvious: 5049.75 squaf+e feet 1 Area Pervious: 2000 squaro feet Peak 0: 0.37 cfs ~ ,,c~ Peak InfiliraGon Rate: 0.36 iNhour ~ ~ Pervious Suriace, non-swale: 4-7 0.00 squere feet /0 c Peak Q, perv, non-sw3te: ` 0.00 cfs Infiltration capacity, perv, nDn-Swa{8: O.QO cf6 Peak 0, remainder. 0.37 cfs ~ Swate Infiftration Capacity: 0.01'14 Ct8 ~ Dryvuell Infiltrativn cap.: 0.3 Cfs Stotsge Requited, 5 minute Stenrt: 17.77 cubiG feet ~ Storage Available, Swale Only: 511.875 113 Plus Otywell: 54.45 c,ubic feet Totat: 566.33 cc,bic feet OK Peak Runofi. 50-yeat storm: (S miRute) ~ § r 54-year intensdy. 8.1 iNhou Peak Q: 0.59 cfs ~ S Storage Requined, 5 minute StOrm: 83_76 OK EnQcatc1-G-36 AUG-04-2009 12:41 509 536 0565 93% P.04 g --c :6 c ~ ~s ~ . . , . r 0 ~ D IN C o Gl °0 I ~ 0) o N ~ m tn r N " ~ m M ~a ~ 0 m w ~ w 0 ~ m w ~ M OC ~ ~ n N O z W ~ ~ z kA ~ 2015 NEw MaRIETrA L-OE-5AC o y~A „ n URB GRADE ° ~ U V a ^ 51A 2 7,5~ v- Oa c m~ =rroA sr~ ow o . 51A 0~?S.YJ ~ D 04 ,IB ~ W ac•Pr (HO~taNnA,) s. arstr 2o.o' ~ a IsnHc cENTtarrE 2005 ~ • ~ t~ II 0 •pf (NOR►Z.) Q ~ Et. 1997.51 r ~ u , ~ .0 ° r ~ Cd m ~ DA7UM EIEV. -'S'" 1f- -81+ `tD1995A0 ~z6ws . 1987.~ ~e ~ cut \ L• SO' EL 1997.98 ~,~Q 3~F~0 NarES: a+oo e= 0.125i+oo L Q 50' e • 0.125' 1, NOTIFY DESIGN ENGINEER IMMEOIATEIY SHOULO ANY 2. CUL-OE-SAC 5TATIONING COUNIER CLOCKwiSE; 3. CtlRB El DtSCREPANCIES EXiST 6E1'WEEN WHAT IS S1i0WN ON ROAOWAY CENTERLINE S1A O~t64.48, N. OFFSET AY GUTTER. 10.0 - CUL-OE--SAC STA 0+00 4. 5EE PI,A THIS FIAN AND ACTUAL FIELO CONOITION$. ~ 14 MARIETTA CUL-DE-SAC PROFiLE AT CURB L1NE o ~ ~ 4 ~ 0 m w ~ 08/08/2000 TUE 11:15 FAX 509 536 0565 TECHCON INC . ~ 4; ~Qpl/ ~~3 . • ~ ~ FAX : TRANSMISSION TECHCON, INC. . East 1230 Front Avenue ` ' Spokane, WA 99202-2148 . Tel: (509)536-0406 FAX: (509)536-0565 From: Alan Gav To: Biil Hemmings , FAX ~ )477-7655 Phone: ( l 477-3600 Date: 8/8I00 Time: Tvtal Pages (includes cover): 3 Deliver To: Mcssagc: Bill: Please Iet me know as soon as possible if this meets what you're looking for on BSP-64-98. If so, T will finalize prints and get Bob Bonuccelli to sign them so that we can get your final approval on thc road and drainage plans. The curnent changes will affect drawin,gs C2.0, C3.0 and e4.0. Alan Gay AUG-08-2000 12=20 509 536 0565 96% P.01 3) ~ o C o~ G) ~ I ~ -q o0 W ~ I N N ° ~ o 0 ~ Ted►C~, Inc. Project; Bonuocellrs Marietta Road Extenslon at SuUfvan ~ 1?30 E. FmM Proj. No. 9&6025 M SpakenE, WA 99202 fID: C;ICIent►Bonuce1ikCurbsec1,YYB2 N &Aug-00 ~ N ~ ~ Typical Section Oafa MARtETTA Cul-de.Sac ~ Max. Cul•de•Sac halt width 45 tt, ~ Road Name: Marieda cn LeN a Right Right m Curb Type: Type R. Spokane Counly Curb Ht, 4 inches Station Interval: 25 feel w ~ 0 MINIMUM MAXIMUM E!P TO ~ Cut•de-Sac CENrER CENTER 46 SLOPE BA9E OF DfSt. % SIOPE DIST, CURB EL. CURB EL. SFLECTED GIIRER ~ kA Cub tINE LINE CENTER CURB C!L TO C11 TO BC FROM E!P (-4.5°k from (•1% from CURB DES{GN TOP CUiiB y 0 p STATION ELEVATION STATlON LINE ELEVATIO~iBC 8C 96 SLOPE TO CURS Cl + CURB HT) CL *.CURB N'EIEVATION % GRADE 96 GRADE n ~ a) ~ n 4 1993.17 64.3 na 1997.79 20 •1.95 TOC ELEV= 1998,12 z (D 15.11 1998.09 49.82 0.53 1997.65 23.73 •1.89 -0.94 1.50 1997,36 5998.19 1997,98 4.00 •0.94 ~ (A 28.18 1998.13 J" -0.33 1997.38 32,14 •1.69 -0.48 1.50 1997.01 1998.14 1997,92 0.00 •0,48 z ~ ~ 33.64 1998.16 35.78 -0.68 1991.58 35,71 •1.62 -0.11 1.50 1996.88 1998.13 1997,55 0.00 NA n 58.64 1998.31 13.01 -0.68 1997.70 44,78 •1.36 0.60 1,50 1998.83 1998,20 1998,04 ~ 63.08 1998.34 1.51 -0.68 1997.73 45 •1.32 1.10 1.50 1996.65 1998,22 1998,06 0.00 4,58 71.71 1998A0 0 -0.68 1 g9,`T.83 44J3 •1.26 1.00 1,50 1996.72 1996,28 ~8,17 O.QO 1,00 81.77 1998.52 -18.21 -0.66 19994T- 38J6 -1.34 1.00 1.54 1997.23 1998.49 19~~3T' o.ou 1,00 ' 133.77 1998.46 36.42 0.33 1998.45 0 NA 1.00 1.54 NA NA 1998,79 0.00 1,00 Nole: curb cut at sb. 0+33.64 ~D W ~ ~ 0 ~ m o N Curbsecl •A-1 w ~ ~ - 60py wgdt RECEBVED Drainage Report, R.A. Bonucce--i AU" o 2 2000 Marietta at Su----ivan:Deve--opment SPOKANECOUnfTY EhGiNEER ~ BSP-64-98 Spokane County, Washington Stateme-n The following report was prepared under niy direction. The contents are engineering oninions derived usi.ng procedures that meet industry and professional standards. This docuinent was not prepared as a construction document. Alan E. Gav Professional Engineer Printed Nanae Title Civil Enineer August 2, 2000 Date ~.v Of WAS~! 194 A'AL E-ltPtRES Trc«CoN, INc. Yrofessional I;ngineers • Certified Cnvironmental Specialists • Project N-lanagers • Steel Uetailers r ~ DRA I:NAGE R_I",PORT I~OBERT A. 'BONUCCELLI MARIETTA AT SLTLL.I,V.AIN'INDUSr['R.~IAL DEVELOPMENT SPOKANE COUNT~.', WASHIIVGTON Praposed iniprovei-nents to ttie sife at the exteiision of M'anetta Road vvest of Sullivan Road, tragge,r the iieed for storrrh water runoff dispasal improvements by Spokane County regulation. The calculation sheets following this narrative include details ofthe a.nalysis showing that ttie proposed drainage irnprovements are adequate to control runoff on the site for a 10-year event, a:nd safely discharge runoff for larger events at a ratc equivaletit to or less thaii the discliarge rate in the pre-developed conditian for the site. Key assulnptions made for the site include assuming that the soils are Garrison gravely loam and Carn'son very stony loarn with an effective per-ineability equal to ar greater than 0.36 inch per hour. (0,36"7h.r). A,rrother key assumption is that the intensity-duration-frequency (IDF) curves for the site confoi-m to the IDF curves for Spokane as publishcd in Chart 34 of the Washington State Depe-irtment ofTranspartatian (WSL~OT) Hyd,rau]ics 1vTanual. The draiiiage areas in the developrncnt arQ deszgnated by parrcel and roadway. Parce1 basins are shown as Parcel 1through 9, with Parcel 4B being held in reserve. Drainage s-Libmittals 'for Parcels 1 through 9 will be n) ade at khe ttmc ai'application for individua] site buil ding perniits. Parcea 4$ niay or ynay not be used for draina.ge for onc or more of Parcels I through 9. Roadway basins are designated as Marietta West, Marietta 1Vliddle and M:arietta East. Each of t:hese basins includes mirror image basins on either side ofthe Man'etta centerline. rI'he Mariet-ta Middle basins drains inta the Marietta West basins, efifec#ively 1nalcing a total of four basins. These drainages are shown with these designations on the drainage a.nd grad-ing plans ,preseiited wi#h this report, as well as the times of concentration for Marietta West, Marietta II41'ddle and NT'arietta East. The Bows#n'ng method was used to assure that the roadside swales will }iave adequate volurne to contaxn a ten year storm event Th~ existing hydralogic coriditions for the site are undeveloped. The calculated pealc ruiiaff for the exisiing site, using the SCS rnethod, fvllows: Q=(P - 0.2S)21 (P + 0.8S), whcre: Q= runoff in efs, 'P = total stann rainfall, S = potential abstraction in inches S= 1 OOD1CN -10 CN = curve number In this case, the CN = 70, ~~nce the sail group is Garrisan, an "I3" hydrologic safl. T'he land use is approximately the sanle as pastue-e in fair coildition, thus the 70 ratilig. S=4.29 P = 3.04 inches in 24 liouYS for a 100 year storm. Q= 0.737 inches over the site. The site drainage basin is appl-oximately the 19.3 acres of the site, since the drainage is bounded on the west by the old Cominco property, which slopes to the west, the north edge of the site is the Johnson Mathey property with its own hydrologic controls, the south edge of the site is the old Milwaukee Railroad right-of-way, and drains toward the south, and the east edge is Sullivan Road. Therefore the total pre-developed runoff from a 100 year event is predicted to be 620,000 cubic fect. For the peak runoff, the hydraulic length is 1234 feet, which equates to an cquivalent area of 19.3 acres. Using the Type II stonn curve, the estitnated peak runoff for a CN70 is 11 cfs/in of runoff. This equates to 8.1 cfs allowable peak runoff. For a 10 year storm, P= 2.12, and Q= 0.287 inches over the site; therefore the allowable peak runoff is 3.16 cfs for a 10 year storm. The predicted peak amount is 0 cfs for the SW and SE basins, unless a runoff-over- ice condition develops that fills over 7000 cubic feet of storage, in which case up to 3 cfs would be discharged through the overflow pipe in the southwest corner of the SW swale. 1 ~ SIOPE 34.1 SIDEWALK TO DRaN ~ TO $WALE BETK'£EN ROAOWAY cfe SlOEWALK ~ 113.26 TC 1998.75 ~C 1998.25 CL El. - L98.0 X` 19996 _ ~ r - - ~ - \ - - - - -X- A{~'~_~g~,~ w 2" IR T10N SERVICE L= 185 LF ~ 1 t~~ W/ METER AND6'A MATIC G- 0.024 _L. 1998.4~ ~ ~ CONTROL. LAYOUT •~Y GRASS AS AlT \ LANOSCAPit1G INSTALLER CHANNEl ~ '`f1Af15 ' \ ~EE OETAiL El. ~ EL 149 wEST ErvD ~ 6 f 1998.65 \ ►eaRl£TTA L-69 LF, C 0.0?9 CRASS CHAroNEI, SEE OETA►L 5/4 BASIh \ Ci EL, ~ wEST MARIETTA I' WATER RVECE CA, \ El. 1997.0 ~ 014gg 16 ~ ROnOSiO SwaLE STUB, - TOTAL AR • 602 S.F, t' ETER, GATE vALVE (TYP EA 5 ) ` sT 9 18 3 ~ BOTTOM E 19 27 STA 0464.4ApCURB PT StA 1+1 0 ` STA'0+66.4$ ~ • 192, 3 \ S. OFfSET 20.5 T6C) C' L. ~ 1996 N. OFFSET 20.5 C) t 9.L STA 0t61.11 \ CURB CUiS ( rA 1. 1 ~ oa• Lor,c ~ r,s`"i.s 1~ 9b ~ o s. ofFSEr ss s' \ ~ " N. OFfSET 23.5" TC=BC 1997J9 SEE OETAIL 17/4 TG I ~cOdb> ORYSh£ll RIM EL. 1997.77 ~ ~ STA 1+73.1 \ ~ I m SEE OETAIL 15/4 ~ S,`aFFSET 20.5 (T8C) ' SiR t+ 0 (TYPICAL Of 2) N. OF SET 20.5 (78C) raa 20 ~ STA 0+67; TOP OF BERM EL, t99829 ~ URB CUTS (2) ~ BERM BETWEEN LOwER, ~ Q 4 LONG wEST ENO SwALE AND CL El. \ iC2001.00 N MIDOLE SWaLE (TYP QF 2) \ 2004c.3 .5EE~DE,T_NLC7/4-~.~.G - - - o -~~=o°ooa,~.oeooG~ooooo~, ~o„=aoo.~ao ~DOLE MARtEnA ~ - 5TA +e ~ ~1 ROADSaOE SwaLE ~ STA t+-91 70TnliRR a 456 S.F. (TYP EACN StOQ ~ S. OFFSET 23.5' sTA N gflTTOk! El. SC0~0,~ 1C~C N. OffSET 23 5 pT G=0.03 2 j ~7 pRYw£LL IM EL. 2001.54 L7 A/.'_`~ i C wc;~SS T Mf~ l.~l~/~;~r S(~•~LL-J SEE\\OETat 15/4 : ~ o ~ STA ~+8i (TYPI~AL OF 2) f B£RM BETri£EN LOWER, ` - f f 1 f ~ ~yu \\~ST ENp SwaLE AND A TO°~L' m M QDLE SWALE (TYP Of 2) r- ,CRES ~ ' ~ - - ~ - STA \ \ 1_ \ fC ~ L. 2041 ~ STA EASfT,1ARr~TiA ~ vF ; 2°''5' ~ TOTA~ AREA 1200 S.F, - C \E ' (TYP EACH SIOE) Z ~T a ; ? , 80TT0M El. SlOPEO Ta Es- a at C=0.03 ~ STA 3+73.3\ + ~S OFFSET 20.5' (TBC) T~TST2A ? - ~ N-,,OfFSET 20.5' (T8C) J' w10E SWALE BOTTOx1r ,,CU R ,C4'T lON G T E'. ?oo ~ (TYP) TCIOC 2007.10 ~ • sT,► I Z SEE OE ail t 7/a E.2 ~ e~~1oooamo~~~ooo~~~ ~ooe ~ _oo=~oo ~~oQOa~o~,oo~ooaooooo~moo~oooa~~ x N-F-- o -z- a ~ ~ El 2008.9 CL 2008. EL. 1 6 BAS__ 0 EaST ENo waaiErTa Bo.Sav ~ • z ~ g ! 1 LANnscAQe SeTeACK l crYPy 1' u ~ .a EC ° ~ 9 2009.~~ fl SEWER EASEMENT RI _ _ a ~ o _ _ _ _ _ - - - -t.- EL - - - - - - - - - - - # 94~1901, 51__~ ----~-~---€----~-~----~----p----~----- ~ oc2 uue~oG~eoe»m or~uooc.c oooLl L I.--iL 71 rD oeo.\ff!D L= rI't--, Bonuccelli Development Marietta & Sullivan 11-Ju1-00 Stormwater Disposal Entire Site is One Parcel Drain to Individual Parcel 208 swales ' Areas Required: Resulting Landscaping Area: TOTAL TOTAL NET NET MAX. UNBUILD- MIN LOADING REQ. Sublot # Type III Type IV AREA ACRES AREA ACRES BUILDING ABLE PARKING DOCK AVAIL? SWALE Imp,Area acres 1 2892.5 0 83135 1.908517 80242.5 1.842114 32422.65 44094.76 1800 OK 6158.994 73907.93 1.696693 2 3499 0 229719 5.273623 226220 5.193297 137831.4 0 56235.15 3600 OK 16003.59 192043 4.408702 3 993.6 0 106456 2,443893 105462.4 2.421054 63873,6 26060.4 2700 OK 7502.33 90027.96 2.066758 4 203.1 0 78459 1,801171 78255.9 1.796508 47075,4 19206.74 1800 OK 5513.456 66161.47 1.518858 5 993.6 0 93875 2.155073 92881.4 2.132264 56325 22980.58 1800 OK 6567.293 78807.52 1.809172 6 950 950 94052 2.159137 92152 2.115519 56431,2 23023.91 1800 OK 6579.393 78952.72 1.812505 7 1003.05 1250 50000 1.147842 47746.95 1.096119 20000 27199.97 360 OK 3736.665 44839.98 1.029384 8 700 0 35000 0.803489 34300 0.78742 14000 19039.98 360 OK 2624.665 31495.98 0.723048 9 1973.55 0 38135 0.875459 36161.45 0.830153 14872.65 20226.78 360 OK 2786.396 33436.76 0.767602 ROADWAY 0 0 37708 0.865657 37708 0.865657 0 0 0 NA 3142.333 37708 0.865657 SWSwale: 3255 0 74739 1.715771 71484 1,641047 0 0 0 0 TOTAL: 921278 21,14963 TOTAL: 60615.11 SQ. FT. 15.17952 Engcalc1-E-1 ~ ~ - Bonuccelli Development Marietta & Sullivan 2-Aug-00 Stormwater Disposal Bowstring Method Calculation, Roadside Swale Capacity, Marietta Area 1: West End, Marietta, TYPICAL EA. SIDE Swale Area: 654.2942 square feet Volume: 1997.27 213.7647 1997.52 434.0295 80.97428 cu.ft. 1997.77 654.2942 217.0147 cu.ft. Pond Infiltration Rate: 0.001781 cfs (0.36"/hr infiltration rate) Drywell Infiltration Rate 0.3 cfs (Garrison Gravelly loam) No. of Drywells: 1 Drywell Volume: 54.45 cubic feet Total Available Storage Volulme: 271.4647 cubic feet Use Bowstring Method to check adequacy of Swale: Time increment; 2 min. Time of Concentration: 2 min. Storage req.: Outflow (c.f.s.) (up to 0 0.00 cfs 239.792 cf. Design year flow 10 year 0.16 Acres Imp; C=0.9 Area (acres) 0.18 Developed C factor: 0.86 0.02 Acres Perv: C=0.4 Area x C 0.15 To flow generated within the West end, add the peak flow coming from lhe middle section below, which also must be drained by the drywell on each side of the West End of Marietta. From Area 2 outflow: 0.284605 cfs occurs after 460 minutes as shown below: No.1 No.2 No.3 No.4 No.S No.6 No.7 Time Inc. t Intensity Q dev. V in V out Storage No. 1 x 60 (in.Ihr) A"C'No.3 Out " No.2 drywell infiltration rate 2 120 318 0.481037 58.05156 0 58.05156 4 240 3.18 0.481037 115.776 0 115.776 6 360 2.9 0.438682 158.2237 0 158.2237 8 480 2.5 0.378174 181.7806 0 181.7806 10 600 2.25 0.340356 204.4453 0 204.4453 15 900 1.76 0.266234 239.792 0 239.792 20 1200 1.45 0.219341 263.3581 90 173.3581 (overflow to drywells) 25 1500 1.22 0.184549 276.9487 103.5906 271.4647 0.045302 cfs 30 1800 1.04 0.15732 283.2835 109.9254 271.4647 0.021116 cfs 35 2100 0.92 0.139168 292.3474 118.9892 271.4647 0.030213 cfs 40 2400 0.82 0.124041 297.7828 124.4246 271.4647 0.018118 cfs 45 2700 0.75 0.113452 306.398 133.0398 271.4647 0.028717 cfs 50 3000 0.69 0.104376 313.1989 139.8408 271.4647 0.02267 cfs 55 3300 0.64 0.096813 319.5471 146.1889 271.4647 0.021161 cfs 60 3600 0.61 0.092274 332.2506 158.8925 271.4647 0.042345 cfs 65 3900 0.60 0.090762 354.0324 180.6743 271.4647 0.072606 cfs 70 4200 0.58 0.087736 368.5522 195.1941 271.4647 0.048399 cfs 75 4500 0.55 0.083198 374.4487 201.0905 271.4647 0.019655 cfs 80 4800 0.53 0.080173 384.8842 211.5261 271.4647 0.034785 cfs 85 5100 0.52 0.077904 397.3624 224.0043 271.4647 0.041594 cfs 90 5400 0.50 0.075635 408.4792 235.121 271.4647 0.037056 cfs 95 5700 0.49 0.074122 422.5462 249.1881 271.4647 0.04689 cfs 100 6000 0.49 0.073366 440.2442 266.8861 271.4647 0.058993 cfs 105 6300 0.45 0.067892 427.7687 254.4106 271.4647 -0.04159 cfs 110 6600 0.44 0.065864 434.75 261.3918 271.4647 0.023271 cfs 115 6900 0.42 0.063983 441.5274 268.1693 271.4647 0.022591 cfs 120 7200 0.41 0.062232 448.1154 274.7572 271.4647 0.02196 cfs 125 7500 0.40 0.060598 454.5268 281.1687 271.4647 0.021371 cfs 130 7800 0.39 0.059068 460.7732 287.4151 271.4647 0.020821 cfs Engcalc1-E-1+1 ' Bonuccelli Development 1 Marietta & Sullivan 2-Aug-00 Stormwater Disposal 135 8100 0.38 0.057633 466.8649 293.5068 271.4647 0.020306 cfs 140 8400 0.37 0.056283 472.8113 299.4532 271.4647 0.019821 cfs 145 8700 0.36 0.05501 478.6208 305.2627 271.4647 0.019365 cfs 150 9000 0.36 0.053807 484.3012 310.9431 271.4647 0.018935 cfs 155 9300 0.35 0.052669 489.8595 316.5013 271.4647 0.018528 cfs 160 9600 0.34 0.05159 495.3021 321.944 271.4647 0.018142 cfs 165 9900 0.33 0.050566 500.6349 327.2768 271.4647 0.017776 cfs 170 10200 0.33 0.049591 505.8635 332.5053 271.4647 0.017428 cfs 175 10500 0.32 0.048663 510.9927 337.6346 271.4647 0.017097 cfs 180 10800 0.32 0.047777 516.0273 342.6692 271.4647 0.016782 cfs 185 11100 0.31 0.046931 520.9715 347.6134 271.4647 0.016481 cfs 190 11400 0.30 0.046123 525.8294 352.4713 271.4647 0.016193 cfs 195 11700 0.30 0.045348 530.6047 357.2466 271.4647 0.015918 cfs 200 12000 0.29 0.044606 535.3008 361.9427 271.4647 0.015654 cfs 205 12300 0.29 0.043894 539.921 366.5629 271.4647 0.015401 cfs . 210 12600 0.29 0.043209 544.4683 371.1102 271.4647 0.015158 cfs 215 12900 0.28 0.042552 548.9456 375.5875 271.4647 0.014924 cfs 220 13200 0.28 0.041919 553.3555 379.9974 271.4647 0.0147 cfs 225 13500 0.27 0.041309 557.7006 384.3425 271.4647 0.014484 cfs 230 13800 0.27 0.040721 561.9832 388.625 271.4647 0.014275 cfs 235 14100 0.27 0.040154 566.2055 392.8473 271.4647 0.014074 cfs 240 14400 0.26 0.039607 570.3696 397.0115 271.4647 0.013881 cfs 245 14700 0.26 0.039078 574.4776 401.1195 271.4647 0.013693 cfs 250 15000 0.25 0.038567 578.5313 405.1732 271.4647 0.013512 cfs 255 15300 0.25 0.038072 582.5325 409.1744 271.4647 0.013337 cfs 260 15600 0.25 0.037593 586.4829 413.1247 271.4647 0.013168 cfs 265 15900 0.25 0.037129 590.384 417.0259 271.4647 0.013004 cfs 270 16200 024 0.03668 594.2375 420.8794 271.4647 0.012845 cfs 275 16500 0.24 0.036244 598.0447 424.6866 271.4647 0.012691 cfs 280 16800 0.24 0.03582 601.8071 428.449 271.4647 0.012541 cfs 285 17100 0.23 0.035409 605.5259 432.1678 271.4647 0.012396 cfs 290 17400 0.23 0.03501 609.2025 435.8444 271.4647 0.012255 cfs 295 17700 0.23 0.034622 612.8379 439.4798 271.4647 0.012118 cfs 300 18000 0.23 0.034245 616.4335 443.0753 271.4647 0.011985 cfs 305 18300 0.22 0.033878 619.9901 446.632 271.4647 0.011856 cfs 310 18600 0.22 0.033521 623.509 450.1508 271.4647 0.011729 cfs 315 18900 0.22 0.033173 626.991 453.6329 271.4647 0.011607 cfs 320 19200 0.22 0.032834 630.4372 457.0791 271.4647 0.011487 cfs 325 19500 0.21 0.032504 633.8485 460.4903 271.4647 0.011371 cfs 330 19800 0.21 0.032182 637.2257 463.8676 271.4647 0.011257 cfs 335 20100 0.21 0.031868 640.5698 467.2116 271.4647 0.011147 cfs 340 20400 0.21 0.031562 643.8814 470.5233 271.4647 0.011039 cfs 345 20700 0.21 0.031263 647.1615 473.8034 271.4647 0.010934 cfs 350 21000 0.20 0.030971 650.4107 477.0526 271.4647 0.010831 cfs 355 21300 0.20 0.030686 653.6298 480.2717 271.4647 0.01073 cfs 360 21600 0.20 0.030407 656.8195 483.4614 271.4647 0.010632 cfs 365 21900 0.20 0.030135 659.9805 486.6223 271.4647 0.010536 cfs 370 22200 0.20 0.029869 663.1133 489.7552 271.4647 0.010443 cfs 375 22500 0.20 0.029609 666.2187 492.8606 271.4647 0.010351 cfs 380 22800 0.19 0.029354 669.2972 495.939 271.4647 0.010262 cfs 385 23100 0.19 0.029105 672.3494 498.9912 271.4647 0.010174 cfs 390 23400 0.19 0.028861 675.3759 502.0177 271.4647 0.010088 cfs 395 23700 0.19 0.028623 678.3771 505.019 271.4647 0.010004 cfs 400 24000 0.19 0.028389 681.3538 507.9956 271.4647 0.009922 cfs 405 24300 0.19 0.02816 684.3062 510.9481 271.4647 0.009842 cfs 410 24600 0.18 0.027936 687.235 513.8769 271.4647 0.009763 cfs Engcalc1-E-1+2 1 ` Bonuccelli Development Marietta & Sullivan 2-Aug-00 Stormwater Disposal 415 24900 0.18 0.027716 690.1406 516.7825 271.4647 0.009685 cfs 420 25200 0.18 0.0275 693.0235 519.6654 271.4647 0.00961 cfs 425 25500 0.18 0.027289 695.8841 522.5259 271.4647 0.009535 cfs 430 25800 0.18 0.027082 698.7228 525.3647 271.4647 0.009462 cfs 435 26100 0.18 0.026878 701.5401 528.182 271.4647 0.009391 cfs 440 26400 0.18 0.026679 704.3364 530.9782 271.4647 0.009321 cfs 445 26700 0.18 0.026483 707.112 533.7539 271.4647 0.009252 cfs 450 27000 0.17 0.026291 709.8674 536.5092 271.4647 0.009185 cfs 455 27300 0.17 0.026102 712.6029 539.2447 271.4647 0.009118 cfs 460 27600 0.17 0.025917 715.3188 541.9607 271.4647 0.009053 cfs 465 27900 0.17 0.025735 718.0156 544.6575 271.4647 0008989 cfs 470 28200 0.17 0.025556 720.6936 547.3354 271.4647 0.008927 cfs 475 28500 0.17 0.02538 723.353 549.9949 271.4647 0.008865 cfs 480 28800 0.17 0.025208 725.9943 552.6361 271.4647 0.008804 cfs 485 29100 0.17 0.025038 728.6177 555.2595 271.4647 0.008745 cfs 490 29400 0.16 0.024871 731.2235 557.8653 271.4647 0.008686 cfs 495 29700 0.16 0.024707 733.812 560.4539 271.4647 0.008628 cfs 500 30000 0.16 0.024546 736.3836 563.0254 271.4647 0.008572 cfs 505 30300 0.16 0.024387 738.9384 565.5803 271.4647 0.008516 cfs 510 30600 0.16 0.024231 741.4768 568.1187 271.4647 0.008461 cfs 515 30900 0.16 0.024077 743.999 570.6409 271.4647 0.008407 cfs 520 31200 0.16 0.023926 746.5054 573.1472 271.4647 0.008354 cfs 525 31500 0.16 0.023777 748.996 575.6379 271.4647 0.008302 cfs 530 31800 0.16 0.023631 751.4713 578.1131 271.4647 0.008251 cfs 535 32100 0.16 0.023486 753.9313 580.5732 271.4647 0.0082 cfs 540 32400 0.15 0.023344 756.3765 583.0183 271.4647 0.00815 cfs 545 32700 0.15 0.023205 758.8069 585.4487 271.4647 0.008101 cfs 550 33000 0.15 0.023067 761.2228 587.8646 271.4647 0.008053 cfs 555 33300 0.15 0.022931 763.6244 590.2663 271.4647 0.008005 cfs 560 33600 0.15 0.022798 766.012 592.6539 271.4647 0.007959 cfs 565 33900 0.15 0.022666 768.3857 595.0276 271.4647 0.007912 cfs 570 34200 0.15 0.022536 770.7458 597.3877 271.4647 0.007867 cfs 575 34500 0.15 0.022408 773.0924 599.7343 271.4647 0.007822 cfs 580 34800 0.15 0.022282 775.4258 602.0676 271.4647 0.007778 cfs 585 35100 0.15 0.022158 777.7461 604.3879 271.4647 0.007734 cfs 590 35400 0.15 0.022035 780.0534 606.6953 271.4647 0.007691 cfs 595 35700 0.14 0.021914 782.3481 608.99 271.4647 0.007649 cfs 600 36000 0.14 0.021795 784.6303 611.2721 271.4647 0.007607 cfs 605 36300 0.14 0.021677 786.9 613.5419 271.4647 0.007566 cfs 610 36600 0.14 0.021561 789.1576 615.7995 271.4647 0.007525 cfs 615 36900 0.14 0.021447 791.4031 618.045 271.4647 0007485 cfs 620 37200 0.14 0.021334 793.6368 620.2787 271.4647 0.007446 cfs 625 37500 0.14 0.021223 881.2403 707.8821 271.4647 0.292012 cfs ~~~vlp ~ S 630 37800 0.14 0.021113 968.8322 795.474 271.4647 0.291973 cfs 635 38100 0.14 0.021004 1056.413 883.0545 271.4647 0.291935 cfs 640 38400 0.14 0.020897 1143.982 970.6238 271.4647 0.291897 cfs ~ Note the decline in the infiltration rate into the drywells in the far right column; this ~ ndicates that the peak infiltration rate (and worst case storage) is reached at 625 minutes when i the middle section begins to drain into the west section swale, in the event of frozen ground. ~ Qlcv-v ratt !S 6 rz iZ Area 2: Middle Section, Marietta TYPICAL EA. SIDE- overflows into and is part of Area 1: ~16 square fee cu.ft. Swale Area: 1090 Volume: 2006.58 30 ~ 2006.83 560 73.75 cu.ft. Engcalc1-E-1+3 / Bonuccelli Development Marietta & Sullivan 2-Aug-00 Stormwater Disposal 2007.58 1090 692.5 cu.ft. Once pond volume is exceeded, then outflow over end berm: Pond Infiltra6on Rate: 0.00025 cfs (0.36"/hr infiltration rate) Drywell Infiltration Rate 0.3 cfs (Garrison Gravelly loam) End Berm,"C" 3 (Broadcrested Weir) End Berm weir equation: 3'L'H^3/2 L= 3 feet; H=.1 feet Therefore Weir outflow: 0.284605 cfs (capacity) No. of Drywells: 0 Drywell Volume: 0 cubic feet Total Available Storage Volulme: 692.5 cubic feet Use Bowstring Method to check adequacy of Swale: Time increment; 2 min. Time of Concentration: 2 min. Storage req.: Outflow (c.f.s.) 0.00 cfs 693.763 cf. Design year flow 10 year 0.107 Acres Imp; C=0.9 Area (acres) 0.132 Developed C factor: 0.805118 0.025 Acres Perv: C=0.4 Area x C 0.106 No.1 No.2 No.3 No.4 No.S No.6 No.7 Time Inc. t Intensity Q dev. V in V out Storage No. 1 x 60 (in./hr) A'C'No.3 Out' No.2 2 120 3.18 0.419328 50.60448 0 50.60448 4 240 3.18 0.419328 100.9238 0 100.9238 6 360 2.9 0.382406 137.9262 0 137.9262 8 480 2.5 0.32966 158.4611 0 158.4611 10 600 2.25 0.296694 178.2183 0 178.2183 15 900 1_76 0.232081 209.0305 0 209.0305 20 1200 1.45 0.191203 229.5735 0 229.5735 25 1500 1.22 0.160874 241.4207 0 241.4207 30 1800 1.04 0.137139 246.9428 0 246.9428 35 2100 0.92 0.121315 254.8439 0 254.8439 40 2400 0.82 0.108129 259.5821 0 259.5821 45 2700 0.75 0.098898 267.092 0 267.092 50 3000 0.69 0.090986 273.0205 0 273.0205 55 3300 0.64 0.084393 278.5544 0 278.5544 60 3600 0.61 0.080437 289.6283 0 289.6283 65 3900 0.60 0.079118 308.6158 0 308.6158 70 4200 0.58 0.076481 321.2729 0 321.2729 75 4500 0.55 0.072525 326.413 0 326.413 80 4800 0.53 0.069888 335.5098 0 335.5098 85 5100 0.52 0.06791 346.3872 0 346.3872 90 5400 0.50 0.065932 356.0779 0 356.0779 95 5700 0.49 0.064613 368.3404 0 368.3404 100 6000 0.49 0.063954 383.768 0 383.768 105 6300 0.45 0.059183 372.8929 0 372.8929 110 6600 0.44 0.057415 378.9786 0 378.9786 115 6900 0.42 0.055775 384.8866 0 384.8866 120 7200 0.41 0.054249 390.6294 0 390.6294 125 7500 0.40 0.052824 396.2184 0 396.2184 130 7800 0.39 0.051491 401.6634 0 401.6634 135 8100 0.38 0.050239 406.9737 0 406.9737 140 8400 0.37 0.049062 412.1572 0 412.1572 145 8700 0.36 0.047953 417.2215 0 4172215 Engcalc1-E-1+4 ~ Bonuccelli Development Marietta & Sullivan 2-Aug-00 Stormwater Disposal 150 9000 0.36 0.046905 422.1732 0 422.1732 155 9300 0.35 0.045913 427.0184 0 427.0184 160 9600 0.34 0.044972 431.7628 0 431.7628 165 9900 0.33 0.044079 436.4116 0 436.4116 170 10200 0.33 0.043229 440.9694 0 440.9694 175 10500 0.32 0.04242 445.4406 0 445.4406 180 10800 0.32 0.041648 449.8293 0 449.8293 185 11100 0.31 0.040911 454.1393 0 454.1393 190 11400 0.30 0.040206 458.374 0 458.374 195 11700 0.30 0.039531 462.5367 0 462.5367 200 12000 0.29 0.038884 466.6304 0 466.6304 205 12300 0.29 0.038263 470.6579 0 470.6579 210 12600 0.29 0.037666 474.6218 0 474.6218 215 12900 0.28 0.037093 478.5248 0 478.5248 220 13200 0.28 0.036541 482.369 0 482.369 225 13500 0.27 0.03601 486.1566 0 486.1566 230 13800 0.27 0.035498 489.8898 0 489.8898 235 14100 0.27 0.035003 493.5705 0 493.5705 240 14400 0.26 0.034526 497.2004 0 497.2004 245 14700 0.26 0.034065 500.7814 0 500.7814 250 15000 0.25 0.033619 504.3151 0 504.3151 255 15300 0.25 0.033188 507.803 0 507.803 260 15600 0.25 0.032771 511.2466 0 511.2466 265 15900 0.25 0.032366 514.6473 0 514.6473 270 16200 0.24 0.031974 518.0064 0 518.0064 275 16500 0.24 0.031594 521.3253 0 521.3253 280 16800 0.24 0.031225 524.605 0 524.605 285 17100 0.23 0.030867 527.8467 0 527.8467 290 17400 0.23 0.030519 531.0516 0 531.0516 295 17700 0.23 0.030181 534.2207 0 534.2207 300 18000 0.23 0.029852 537.355 0 537.355 305 18300 0.22 0.029532 540.4554 0 540.4554 310 18600 0.22 0.029221 543.5228 0 543.5228 315 18900 0.22 0.028917 546.5582 0 546.5582 320 19200 0.22 0.028622 549.5623 0 549.5623 325 19500 0.21 0.028334 552.536 0 552.536 330 19800 0.21 0.028054 555.4799 0 555.4799 335 20100 0.21 0.02778 558.395 0 558.395 340 20400 0.21 0.027513 561.2818 0 561.2818 345 20700 0.21 0.027252 564.1411 0 564.1411 350 21000 0.20 0.026998 566.9735 0 566.9735 355 21300 0.20 0.026749 569.7797 0 569.7797 360 21600 0.20 0.026507 572.5602 0 572.5602 365 21900 0.20 0.026269 575.3156 0 575.3156 370 22200 0.20 0.026037 578.0466 0 578.0466 375 22500 0.20 0.02581 580.7536 0 580.7536 380 22800 0.19 0.025589 583.4372 0 583.4372 385 23100 0.19 0.025371 586.0978 0 586.0978 390 23400 0.19 0.025159 588.736 0 588.736 395 23700 0.19 0.024951 591.3523 0 591.3523 400 24000 0.19 0.024747 593.9471 0 593.9471 405 24300 0.19 0.024547 596.5208 0 596.5208 410 24600 0.18 0.024352 599.0739 0 599.0739 415 24900 0.18 0.02416 601.6067 0 601.6067 420 25200 0.18 0.023972 604.1198 0 604.1198 425 25500 0.18 0.023788 606.6134 0 606.6134 Engcalc1-E-1+5 , Bonuccelli Development Marietta & Sullivan 2-Aug-00 Storrriwater Disposal 430 25800 0.18 0.023607 609.088 0 609.088 435 26100 0.18 0.02343 611.5438 0 611.5438 440 26400 0.18 0.023256 613.9814 0 613.9814 445 26700 0.18 0.023086 616.401 0 616.401 450 27000 0.17 0.022918 618.8029 0 618.8029 455 27300 0.17 0.022754 621.1874 0 621.1874 460 27600 0.17 0.022592 623.555 0 623.555 465 27900 0.17 0.022433 625.9058 0 625.9058 470 28200 0.17 0.022277 628.2402 0 628.2402 475 28500 0.17 0.022124 630.5585 0 630.5585 480 28800 0.17 0.021974 632.8609 0 632.8609 485 29100 0.17 0.021826 635.1478 0 635.1478 490 29400 0.16 0.02168 637.4193 0 637.4193 495 29700 0.16 0.021537 639.6758 0 639.6758 500 30000 0.16 0.021397 641.9174 0 641.9174 505 30300 0.16 0.021258 644.1445 0 644.1445 510 30600 0.16 0.021122 646.3573 0 646.3573 515 30900 0.16 0.020988 648.556 0 648.556 520 31200 0.16 0.020857 650.7408 0 650.7408 525 31500 0.16 0.020727 652.9119 0 652.9119 530 31800 0.16 0.020599 655.0696 0 655.0696 535 32100 0.16 0.020474 657.2141 0 657.2141 540 32400 0.15 0.02035 659.3456 0 659.3456 545 32700 0.15 0.020228 661.4642 0 661.4642 550 33000 0.15 0.020108 663.5702 0 663.5702 555 33300 0.15 0.019989 665.6638 0 665.6638 560 33600 0.15 0.019873 667.745 0 667.745 565 33900 0.15 0.019758 669.8143 0 669.8143 570 34200 0.15 0.019645 671.8716 0 671.8716 575 34500 0.15 0.019533 673.9172 0 673.9172 580 34800 0.15 0.019424 675.9512 0 675.9512 585 35100 0.15 0.019315 677.9738 0 677.9738 590 35400 0.15 0.019208 679.9852 0 679.9852 595 35700 0.14 0.019103 681.9855 0 681.9855 600 36000 0.14 0.018999 683.9749 0 683.9749 605 36300 0.14 0.018896 685.9535 0 685.9535 610 36600 0.14 0.018795 687.9214 0 687.9214 615 36900 0.14 0.018696 689.8789 0 689.8789 620 37200 0.14 0.018597 691.826 0 691.826 625 37500 0.14 0.0185 693.763 0 693.763 Begin Weir Overfiow 630 37800 0.14 0.018404 695.6898 85.3815 610.3083 to Area 1 Area 3: East End, Marietta TYPICAL EA. SIDE Swale Area: 2000 square feet Volume: 1997.27 18 1997.52 1009 128.375 cu.ft. 1997.77 2000 504.5 cu.ft. Pond Infilkration Rate: 0.00015 cfs (0.36"/hr infiltration rate) N 0 Drywell Infiltration Rate 0.3 cfs (Garrison Gravelly loam) No. of Drywells: 1 Drywell Volume: 54.45 cubic feet C(~pt Total Available Storage Volulme: 558.95 cubic feet Use Bowstring Method to check adequacy of Swale: Time increment; 2 min. Engcalcl-E-1+6 ' i Bonuccelli Development Marietta & Sullivan 2-Aug-0O ~ Stormwater Disposal Time of Concentration: 2 min. Storage req.: ~ Outflow (c.f.s.) (up to 0 0.00 cfs 558.95 cf. Design year flow 10 year 0.098 Acres Imp; C=0.9 Area (acres) 0.143 Developed C factor: 0.74 0.046 Acres Perv: C=0.4 Area x C 0.106 No.1 No.2 No.3 No.4 No.S No.6 No.7 Time Inc. t Intensity Q dev. V in V out Storage No. 1 x 60 (in./hr) A*C"No.3 Out ' No.2 2 120 3.18 0.456267 55.06233 0 55.06233 0 4 240 3.18 0.481037 115.776 0 115.776 0 6 360 2.9 0.438682 158.2237 0 158.2237 0 8 480 2.5 0.378174 181.7806 0 181.7806 0 10 600 2.25 0.340356 204.4453 0 204.4453 0 15 900 1.76 0.266234 239.792 0 239.792 0 20 1200 1.45 0.219341 263.3581 0 263.3581 0 25 1500 1.22 0.184549 276.9487 0 276.9487 0 30 1800 1.04 0.15732 283.2835 0 283.2835 0 35 2100 0.92 0.139168 292.3474 0 292.3474 0 40 2400 0.82 0.124041 297.7828 0 297.7828 0 45 2700 0.75 0.113452 306.398 0 306.398 0 50 3000 0.69 0.104376 313.1989 0 313.1989 0 55 3300 0.64 0.096813 319.5471 0 319.5471 0 60 3600 0.61 0.092274 332 2506 0 332.2506 0 65 3900 0.60 0.090762 354.0324 0 354.0324 0 70 4200 0.58 0.087736 368.5522 0 368.5522 0 75 4500 0.55 0.083198 374.4487 0 374.4487 0 80 4800 0.53 0.080173 384.8842 0 384.8842 0 85 5100 0.52 0.077904 397.3624 0 397.3624 . 0 90 5400 0.50 0.075635 408.4792 0 408.4792 0 95 5700 0.49 0.074122 422.5462 0 422.5462 0 100 6000 0.49 0.073366 440.2442 0 440.2442 0 105 6300 0.45 0.067892 427.7687 0 427.7687 0 110 6600 0.44 0.065864 434.75 0 434.75 0 115 6900 0.42 0.063983 441.5274 0 441.5274 0 120 7200 0.41 0.062232 448.1154 0 448.1154 0 125 7500 0.40 0.060598 454.5268 0 454.5268 0 130 7800 0.39 0.059068 460.7732 0 460.7732 0 135 8100 0.38 0.057633 466.8649 0 466.8649 0 140 8400 0.37 0.056283 472.8113 0 472.8113 0 145 8700 0.36 0.05501 478.6208 0 478.6208 0 150 9000 0.36 0.053807 484.3012 0 484.3012 0 155 9300 0.35 0.052669 489.8595 0 489.8595 0 160 9600 0.34 0.05159 495.3021 0 495.3021 0 165 9900 0.33 0.050566 500.6349 0 500.6349 0 170 10200 0.33 0.049591 505.8635 0 505.8635 0 175 10500 0.32 0.048663 510.9927 90 420.9927 0.3 180 10800 0.32 0.047777 516.0273 95.03459 558.95 0.016782 185 11100 0.31 0.046931 520.9715 99.97883 558.95 0.016481 Note the decline in the infiltration rate into the drywells in the far right column; this indicates that the peak infrltration rate (and worst case storage) is reached at 175 minutes when the overflow from the swale begins to enter the drywell grate, in the event of frozen ground. Worst Case Inlet Depression, Type 1 Inlet: 0.1 ft. Engcalcl-E-1+7 Bonuccelli Development Marietta & Sullivan 2-Aug-00 Stormwater Disposal Flow: 0.476934 cfs = Qmax (use TR55 flow calc where applicable) maximum allowable ponding: 0.2 feet = h = head for weir of inlet opening Required area of inlets: Cw= 3 Q=Cw'Lh^(3/2) L=Q/(Cw'h^(312)) Lmin.= 1.777428 feet Therefore a 4' long inlet will be more than adequate for a 10-year storm event for each curb inlet. Worst Case Drywell Inlet flow: Flow: 0.48 cfs = Qmax (use TR55 flow calc where applicable) maximum allowable ponding: . 0.4 feet = h = head for weir of drywell opening Required area of drywell grate: Cw= 3 Q=Cw'Lh^(3/2) L=Q/(Cw"h^(3/2)) Lmin.= 0.628416 feet Therefore a standard type 4 grate with an effective weir length of 5.694137 feet Is adequate for much more than a 10-year storm event for each drywell. Engcalc1-E-1+8 ' e Bonuccelli Development industrial Development at Sullivan and Marietta 2-Aug-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Use conservative 5 min. intensity i= 3.2 in/hr Disposal Capacity: Gamson Gravelly Loam/Very Stony Loam Soil Estimated Turf Infiltration Capacity q= 0.36 in/hr Ratio of ilq 8.888889 Maximum Storage Depth: 6 in. 10 year, one hour intensity: 3 2 in/hr 10 year, 24 hour total: 2.12 in. Parcel 1 Drain Basin Total Improved Imperoious Surface Area: 73907.93 square feet Asphalt Impervious Surface Area: new: 39281 square feet Roof: direct: 32422.65 square feet Sidewalk: new: 2204.738 square feet Utilize biofiltralion swale (grassy) for disposal. Assume antecedant saturated soil conditions: U61ize Spokane County Type A drywells for over(low. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 9227.066 square feet Depressed Infiltration Area: 6158.994 square feet cultivated surface Additional available infiltration volume on side slopes: Perimeter 6" above bottom 470.8756 square feet additional on slopes Total Available for Infiltration: 6629 87 square fee = 3197.216 ft3 Total Required Under County Standard: 1636.689 ft3 OK Hydrology Check: Rational Method• Peak Runoff, 10-year storm, Q=CIA Impervious Sur-face C: 0.9 Pervious Surface C: 0.25 10-year intensity: 3.2 in/hour Time of concentration: 3.65 min. Area Impervious: 73907.93 square feet Area Pervious: 9227.066 square feet Peak Q: 5 06 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale: 2597.196 square feet Peak Q, perv, non-swale: 0.05 cfs Infiltration capacity, perv, non swale 0.02 cfs , Engcalc1-G-1 y Bonuccelli Development Induslrial Development at Sullivan and Marietta 2-Aug-00 TechCon, Inc. I'repared by Alan E. Gay, P.E. _ Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Peak Q, remainder: 5.03 cfs Swale Infiltration Capacity: 0.0552 cfs drywell infiltration cap.: 0.3 cfs each (1 total) Storage Required, 5 minute Storm: 1403.71 cubic feet Storage Available, Swale Only: 3197.216 cubic feet Plus Drywells: 54.45 cubic feet Total: 3251.67 cubic feet OK Peak Runoff, 50-year storm: (5 minute) 50-year intensity: 5.1 in/hour Peak Q: 8.06 cfs Storage Required. 2394 30 cubic feet Swale Plus Drywell: 3251.67 cubic feet OK Parcel 2 Drain Basin Total Improved Impervious Surface Area- 192043 square feet Asphalt Impervious Surface Area: new: 51400 square feet Roof: direct: 137831.4 square feet Sidewalk: new. 2811 758 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedani saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 37675.96 square feet Depressed Infiltration Area: 16003.59 square feet cultwated surface Additional available infiltration volume on side slopes: Perimeter 6" above bottom 759.0317 square feet additional on slopes Total Available for Infiltration: 16762.62 square fee = 8191.551 ft3 Total Required Under Counly Standard: 2141.662 f13 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year inlensity: 1.95 inlhour Time of concentration: 13 min. Area Impervious: 192043 square feet Area Pervious: 37675.96 square feet Peak Q: 8.16 cfs Peak Infiltration Rate: 0.36 inlhour Pervious Surface, non-swale: 20913.34 square feet Engcalcl-G-2 . , Bonuccelli Development Industriai Development at Sullivan and Marietta 2-Aug-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Peak Q, perv, non-swale: 0.23 cfs Infiltration capacity, perv, non swale: 0.17 cfs Peak Q, remainder: 7.98 cfs Swale Infiltration Capacity: 0.1397 cfs drywell infiltration cap.: 0.3 cfs each (1 total) Storage Required, 13 minute Storm: 5885.06 cubic feet Storage Available, Swale Only: 8191.551 cubic feet Plus Drywells: 54.45 cubic feet Total: 8246.006 cubic feet OK Peak Runoff, 50-year storm: (13 minute) 50-year intensity: 2.7 in/hour Peak Q: 11.30 cis Storage Required. 8751.66 cubic feet Swale Plus Drywell: 8246.006 cubic feet NG Storage Available, 12": 16762.62 cubic feet OK Parcel 3 Drain Basin Total Improved Impervious Surface Area: 90027.96 square feet Asphalt Impervious Surface Area: new: 24851 square feet Roof: direct: 63873.6 square feet Sidewalk; new: 1303.02 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 16428.04 square feet Depressed Infiltration Area: 7502.33 square feet cultivated surface Additional available infiltration volume on side slopes: Perimeter 6" above bottom 519.696 square feet additional on slopes Total Available for Infiltration: 8022.026 square fee = 3881 089 ft3 Total Required Under County Standard: 1035.473 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C- 0 25 10-year mtensity• 3.2 inlhour ' Time of concentration: 4.6 min Area Impervious; 90027.96 square feet Area Pervious: 16428.04 square feet Engcalcl-G-3 ~ y Bonuccelli Development Industrial Devetopment at Sullivan and Marietta 2-Aug-00 YechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year slorm (for review by Spokane County Engineers). Peak Q: G 25 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale: 8406.011 square feet Peak Q, perv, non-swale: 0.15 cfs Infiltration capacity, perv, non swale: 0.07 cfs Peak Q, remainder: 6.18 c(s Swale Infiltration Capacity: 0.0669 cfs drywell infiltration cap.• 0.3 cfs each (1 total) Storage Required, 5 minute Storm: 1745.12 cubic feet Storage Available, Swale Only: 3881.089 cubic feet Plus Orywells: 54.45 cubic feet Total• 3935.543 cubic feet OK Peak Runoff, 50-year storm: (5 minute) 50-year intensity: 5.1 in/hour Peak Q: 9.97 cfs Storage Required: 2967.11 cubic feet Swale Plus Drywell: 3935.543 cubic feet OK Parcel 4 Drain Basin Total Improved Impervious Surface Area 66161 47 square feet Asphalt Impervious Surface Area: new: 18126 square feet Roof: direct. 47075.4 square feet Sidewalk• new: 960.3372 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell mfiltration capacity. Available Grassy Area: 12297.53 square feet Depressed Infiltration Area: 5513.456 square feet cultivated surface Additional available infiltration volume on side slopes• Perimeter 6" above bottom 445.5159 square feet additional on slopes Total Available for Infiltration: 5958.972 square fee = 2868.107 ft3 Total Required Under County Standard• 755.2388 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 Engcalc1-G-4 . + Bonuccelli Development Industrial Development at Sullivan and Marietta 2-Aug-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design l0 10 year storm (for review by Spokane County Engineers). 10-year intensity: 2.5 in/hour Time of concentralion: 8 min. Area Impervious: 66161.47 square feet Area Pervious: 12297.53 square feet Peak Q: 3.59 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale: 6338.559 square feet Peak Q, perv, non-swale: 0.09 cfs Infiltration capacity, perv, non swale: 0.05 cfs . Peak Q, remainder: 3.54 cfs Swale Infiltration Capacity: 0.0497 cfs drywell infiltration cap.: 0.3 cfs each (1 total) Storage Required, 8 minute Storm: 1531.87 cubic feet Storage Avadable, Swale Only: 2868.107 cubic feet Plus Drywells: 54.45 cubic feet Total: 2922.561 cubic feet OK Peak RunoN, 50-year storm: (8 minute) 50-year intensity: 3.65 in/hour Peak Q: 5.25 cfs Storage Required: 2481.68 cubic feet Swale Plus Drywell: 2922.561 cubic feet OK Parcel 5 Drain Basin Total Improved Impervious Surface Area: 78807.52 square feet Asphalt Impervious Surface Area: new: 21333 square feet Roof: direct: 56325 square feet Sidewalk: new. 1149.029 square feet Ulilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 15067.48 square feet Depressed Infiltration Area: 6567.293 square feet cultivated surface Additional available infiltration volume on side slopes: Perimeter 6" above bottom 486.233 square feet additional on slopes Total Available for Infiltration: 7053.526 square fee = 3405.205 ft3 Total Required Under Counly Standard. 888.8954 fl3 OK Hydrology Check: Engcalcl-G-S 1 ~ Bonuccelli Development Industnal Development at Suilivan and Marietta 2-Aug-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Sludy Design to 10 year storm (for review by Spokane County Engineers). Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0 25 10-year intensity: 2.6 in/hour Time of Concentration: 7.5 min. Area Impervious: 78807.52 square feet Area Pervious: 15067.48 square feet Peak Q: 4.46 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale: 8013.954 square feet , Peak Q, penr, non-swate: 0.12 cfs Infiltration capacity, perv, non swale: 0.07 cfs Peak Q, remainder: 4 39 cfs Swale Infiltration Capacity. 0.0588 cfs drywell infiltralion cap : 0.3 cfs each (1 total) Storage Required, 7.5 minute Storm: 1814.73 cubic feet Storage Available, Swale Only: 3405 205 cubic feet Plus Drywells: 54.45 cubic feet Total: 3459 659 cubic feet OK Peak Runoff, 50-year storm- (7.5 minute) 50-year intensity: 3.8 in/hour Peak Q: 6.52 cfs Storage Required: 2897.59 cubic feet Swale Plus Drywell: 3459.659 cubic feet OK Parccl 6 Drain Basin Total Improved Impervious SurFace Area: 78952.72 square feet Asphalt Impervious Surface Area: new: 21370 square feet Roof: direct: 56431.2 square feet Sidewalk: new: 1151.195 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiliration capacity. Available Grassy Area: 15099.28 square feet Depressed Infiltration Area. . 6579 393 square feet cultivated surface Additional available infiltration volume on side slopes- Perimeter 6" above bottom 486.6807 square feet additional on slopes Total Available for Infiltration• Engcalcl-G-6 ~ Y Bonuccelli Development Industrial Development at Sullivan and Marietta 2-Aug-00 TechCon, Inc Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). 7066.074 square fee = 3411.367 ft3 Total Required Under County Standard: 890.43 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year intensity: 2.6 in/hour Time of concenlration: 7.5 min. Area Impervious: 78952.72 square feet Area Pervious: 15099.28 square feet Peak Q. 4 47 cfs Peak Infiltration Rate: 0.36 in/hour Pervious SurFace, non-swale: 8033.21 square feel Peak Q, perv, non-swale. 012 cfs Infiltration capacity, perv, non swale: 0.07 cfs Peak Q, remainder: 4.40 cfs Swale Infiltration Capacity: 0.0589 cfs drywell infiltration cap.: 0.3 cfs each (1 total) Storage Required, 7.5 minute Storm: 1818.34 cubic feet Storage Available, Swale Only: 3411.367 cubic feet Plus Drywells: 54.45 cubic feet Total: 3465.821 cubic feet OK Peak Runoff, 50-year storm: (7.5 minute) 50-year intensiiy: 3.8 in/hour Peak Q. 6.53 cfs Storage Required: 2903.03 cubic feet Swale Plus Drywell: 3465.821 cubic feet OK Parcel 7 Drain Basin Total Improved Irnpervious SurFace Area. 44839.98 square feet Asphalt Impervious Surface Area: new: 23480 square feet Roof: direct: 20000 square feet Sidewalk: new: 1359.999 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 5160.024 square feet Depressed Infiltration Area: 3736 665 square feet cultivated surface Engcalc1-G-7 Bonuccelli Development Industrial Development at Sullivan and Marietta 2-Aug-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Additional available infiltration volume on side slopes: Perimeter 6" above bottom 366.7696 square feet additional on slopes 7otal Available for Infiltration: 4103.434 square fee = 1960.025 ft3 7otal Required Under County Standard: 978.3324 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year intensity: 3.2 in/hour Time of concentration: 3 min. Area Impervious: 44839.98 square feet Area Pervious: 5160.024 square feet Peak Q: 3.06 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale: 1056.59 square feei Peak Q, perv, non-swale: 0.02 cfs Infiltration capacity, perv, non swale: 0.01 cfs Peak Q, remainder: 3 05 cfs Swale Infiltration Capacity: 0.0342 cfs drywell infiltration cap.- 0.3 cfs each (1 total) Storage Required, 5 minute Storm: 814.92 cubic feet Storage Available, Swale Only: 1960.025 cubic feet Plus Drywells: 54.45 cubic feet Total: 2014.479 cubic feet OK Peak Runoff, 50-year storm: (5 minute) 50-year intensity• 5.1 in/hour Peak Q: 4.88 cfs Storage Required: 1439.70 cubic feet Swale Plus Drywell: 2014.479 cubic feet OK Parcel 8 Draln Basin Total Improved Impervious Surface Area. 31495 98 square feet Asphalt Impervious Surface Area: new: 16544 square feet Roof: direct: 14000 square feet Sidewalk. new: 951.999 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Engcalcl-G-8 Bonuccelli Development Industrial Development at Sullivan and Marietta 2-Aug-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Available Grassy Area. _ 3504.017 square feet Depressed Infiltration Area: 2624.665 square feet cultivated surface Additional available infiltration volume on side slopes: Perimeter 6" above bottom 347.3889 square feet additional on slopes Total Available for Infiltration: 2932.054 square fee = 1389.18 ft3 Total Required Under County Standard: 689.3327 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Peroious Surface C: 0.25 10-year intensity: 3.2 in/hour Time of concentration: 5 min. Area Impervious: 31495.98 square feet Area Pervious: 3504.017 square feet Peak Q: 2.15 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale• 571.963 square feet Peak Q, perv, non-swale: 0.01 cfs Infiltration capacity, perv, non swale: 0.00 cfs Peak Q, remainder: 2.14 cfs Swale Infiltration Capacity. 0.0244 cfs drywell mfiltration cap.: 0.3 cfs each (1 total) Storage Required, 5 minute Storm: 545.26 cubic feet Storage Available, Swale Only: . 1389.18 cubic feet Plus Drywells: 54.45 cubic feet Total: 1443.634 cubic feet OK - Peak Runoff, 50-year storm: (5 minute) 50-year intensily: 5.1 inlhour Peak Q: 3.42 cfs Storage Required• 1003.34 cubic feet Swale Plus Drywell: 1443.634 cubic feet OK Parcel 9 Drain Basin Total Improved Impervious Surface Area: 33436 76 square feet Asphalt Impervious Surface Area- new: 17553 square feet Roof: direct: 14872.65 square feet Sidewalk: Engcalc1-G-9 ' ~ e Bonuccelli Development Industrial Development at Sullivan and Marietta 2-Aug-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). new: 1011.339 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 4698_245 square feet Depressed Infiltration Area: 2786.396 square feet cultivated surface Additional available infiltration volume on side slopes: Perimeter 6" above bottom 316.718 square feet additional on slopes Total Available for Infiltration: 3103.114 square fee = 1472.378 ft3 Total Required Under County Standard: 731.3653 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year intensity: 3.2 in/hour Time of concentration: 5 min. Area Impervious: 33436.76 square feet Area Pervious: 4698 245 square feet Peak Q: 2.30 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale: 1595.13 square feet Peak Q, perv, non-swale: 0.03 cfs Infiltration capacity, perv, non swale: 0.01 cfs Peak Q, remainder: 2.28 cfs Swale Infiltration Capacity: 0.0259 cfs drywell infiltration cap.: 0.3 cfs each (1 total) Storage Required, 5 minute Storm: 587.35 cubic feet Slorage Availabte, Swale Only: 1472.378 cubic feet Plus Orywells: 54.45 cubic feet Total: 1526.832 cubic feet OK Peak Runoff, 50-year storm: (5 mmute) 50-year intensity: 5.1 inlhour Peak Q: 3.66 cfs Storage Required: 1075.18 cubic feet Swale Plus Drywell: 1526.832 cubic feet OK Roadway Basins: West End, North and South Sides: (Mirror Images) Total Improved Impervious Surface Area: 7031.876 square feet Asphalt Impervious Surface Area: Engcalcl-G-10 • 1 Bonuccelli Development Industrial Development at Sullivan and Marietta 2-Aug-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). new: 5159.04 square feet Roof: new: 0 square feet Sidewalk: new: 1872.837 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: 1 Drywell necessary Available Grassy Area: 654.2942 square feet Depressed Infiltration Area: 213.7647 square feet cultivated surface Additional available infiltration volume on side slopes: Assume 3:1 slopes 1.5 feet wide strip around depression Swale: 440.5295 square feet: up to 6" available for storage on 3-1 slopes Total Available for Infiltration: North: 654.2942 square fee = 217.0147 ft3 Total Required Under County Standard: 214.96 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year intensity: 3.2 in/hour Time of concentration: 1 min. Area Impervious: 7031.876 square feet Area Penrious: 654.2942 square feet ~ Peak Q: 0.48 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale: 0 square feet Peak Q, perv, non-swale: 0.00 cfs Infiltration capacity, perv, non swale: 0.00 cfs Peak Q, remainder: 0.48 cfs Swale Infiltration Capacity: 0.0055 cfs Drywell infiltratin cap.: 0.3 cfs Storage Required, 5 minute Storm: 51.44 cubic feet Storage Available, Swale Only: 217.0147 cubic feet Plus Drywell. 54.45 cubic feet Total: 271.469 cubic feet OK Peak Runoff, 50-year storm: (5 minute) 50-year intensity: 5.1 m/hour Peak Q: 0.76 cfs Storage Required: 136.40 cubic feet OK Roadway Basins: Middle, North and South Sides: (Mirror Images) Engcalcl-G-11 Bonuccelli Development Industrial Developrneni at Suliivan and Marietta 2-Aug-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engmeers). Total Improved Impervious Surface Area: 4654 squarefeet Asphalt Impervious Surface Area: new: 3700 square feet Roof: new: 0 square feet Sidewalk: new: 954 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturaled soil conditions: no drywell necessary Available Grassy Area: 1090 square feet Depressed Infiltration Area: . 30 square feet cultivated surface Additional available infiltration volume on side slopes: Assume 3•1 slopes 1.5 feet wide strip around depression Swale: 1060 square feet: up to 6" available for storage on 3:1 slopes Total Available for Infiltration: North: 1090 square fee = 692.5 ft3 Total Required Under County Standard: 154.1667 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C. 0.9 Pervious Surface C: 0.25 10-year intensity: 3.2 in/hour 7ime of concentration: 1 min. Area Impervious: 4654 square feet Area Pervious: 1090 square feet Peak Q: 0.33 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale: 0 square feet Peak Q, perv, non-swale: 0.00 cfs Infiltration capacity, perv, non swale: 0.00 cfs Peak Q, remainder. 0.33 cfs Swale Infiltration Capacity: 0.0091 cfs Drywell infiltratin cap.: 0 cfs Storage Required, 5 minute Storm: 95.59 cubic feet Storage Available, Swale Only: 692.5 cubic feet Plus Drywell. 0.00 cubic feet Total: 692.5 cubic feet OK Peak Runoff, 50-year storm: (5 minute) 50-year intensity. 5.1 in/hour Peak Q: 0.52 cfs Storage Required: Engcalc1-G-12 / Bonuccelli Development Industrial Development at Sullivan and NAarietta 2-Aug-00 TechCon, Inc Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). 153.97 cubic feet OK Roadway Basins: East End, North and South Sides: (Mirror Images) Total Improved Impervious Surface Area: 5050 square feet Asphalt Impervious Surface Area: new: 3561 square feet Roof. new: 0 square feet Sidewalk. new: 1488.75 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: 1 Orywell Available Grassy Area: 2000 square feet Depressed tnfiltration Area: 18 square feet cultivated surface , Additional available infiltration volume on side slopes' Assume 3:1 slopes 1.5 feet wide strip around depression Swale. 1982 square feet- up to 6" available for storage on 3.1 slopes Total Available for Infiltration: North: 2000 square fee = 504.5 ft3 Total Required Under County Standard: 148.3854 ft3 OK Nydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year intensity: 3.2 in/hour Time of concentration: 1 min. Area Impervious: 5050 square feet Area Peroious: 2000 square feet Peak Q: 0.37 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale: 0 square feet Peak Q, perv, non-swale: 0 00 cfs Infiltration capacity, perv, non swale: 0.00 cfs Peak Q, remainder: 0.37 cfs Swale Infiltration Capacity: 0.0167 cfs Drywell infiltratin cap., 0 cfs Storage Required, 5 minute Storm: 108.46 cubic feet Storage Available, Swale Only: 504.5 cubic feet Plus Drywell: 0 00 cubic feet Total: 504.5 cubic feet OK Peak Runoff, 50-year storm: (5 minute) Engcalc 1-G-13 Borrueeelli Develapment fndustrial Develqpmen# at SuNivan and Marietta 2-Au g-00 TechCon, Inc_ Prepared by Alan E. Gay, P.E. Si#e Hytirology Study Design tfl 10 year storrn (for review by Spokane Caun#y Engineer8)- 54-year intensity' 5.1 inlhour Peak 4: 0_59 cfs $torage Required: 174.48 cubic feet OK Existing Pre-developed Site Total Imprflved Irnperuiaus Surface Area; 0 square feet Asphal# I mpervious 5urface Area; new: 0 square feet Raof: new• 4 square feet Sidewalk: new; 0 square feet Available Grassy Area: 921218 square ieet Depressed Infiltration Area_ 0 square feet +cultivated surface Additional 2vailable infi!#ration uolume on side slopes. Assume 3-1 slapes 0 feet vygde strip around depression Swale: 0 scluare feet; up ta 6" available for storage vn 3; 1 slopes 7atal AvaiIable far Infiltrakion: North- 0 square fee = 0 ft3 Tatal Requ+red Under Counl'y Standard, Q ft3 QK Hydrofogy Check: Rational N[ethod: SCS Method : Peak Runoff, 10-yearstorm, Q-CIA 24 hour storm Impervious Surface C: 0.9 Tc = 25.25 minutes Pervious Surface C- 0.25 Tot,al Area 21.15 acres 10-year inten sity: 09 inPhour Tirne of cancentrakion: 36.2 rrrin. Area Impervious: 0 square feet SCS cunre Na. fi Area Pervious: 921275 squarE feet 10-year 24 hour starm: Peak Q: 4,76 cfs 2.12 inches SCS Type II Storm Peak Infiltratian Rate: 0,36 i0hour SCS 140 Hydragraph Pervious SurFace, non-s>wale: 921278 square 1'eek simulate capacaly of drywell as Peak Q, Perv, non-swale: 0.75 foot tiiameter orifice (nc) drywell} 4.78 cfs InfiItFatl4n capaCity, penr, non swafe: Capacity is adequake, 7.68 cf5 HydQaulic Capacity of Dr}rwell is Peak Q, rernainder: 0 cfs O,i70 cfs Peak f'IQw: 0,08 cfs 5wale fnfiltration Gapaci#y: 0.0000 crs Engcalc1-G-14 o Submittal Checklist s10 ,t~ f.or Road & Draiaage Projects in Spokane County - Plats/Short VA,y 0 F~'✓ 7'his Subntitlal Checklist is to be completed and signeal by the Sponsor's Engineer, and inclucled with eac~ipon submittal rnto the Spokane County Cngineers Offtce. If thrs form is not f{lly completed and signecl, do n~t submit plans and calculatinns to Spokane Counry far review and acceptance. Incomplete submittals will be returned and will cause unnecessary delays for your client. im Gc J' C 44a a 4- .'__iffu a4,v Project Name. . SPokane CountY ProJ~ect No. ~ Date: - Project Engineer: 7AC-4 CONA, ~►'~.~L ~ Phone: 92- A. qV3Project Sponsor: P, A Phone: Preliminary Process Prior to Submittal of. Road and Drainage Plans, the following events are to have already occurred: (13y checking each itenr off shown helow, yoii are stating that you have verified these evenfs/items have been completed.) 0Adoption of a Hearing Examiner's Report for this long plat, or a Plaruilllg Report for this short plal. At least one Pre-Design Meeting has been held with County staff at the Engineers Officc. LR~ An "Agreement to Pay Fees" has been signed by the project sponsor, and submitted to the County Enguleers Office. B~ A Channelization Plan (e.g. signing and striping plan) of public roadway improvements, has been coordinated and discussed with the County Engineers Officc. B. Road and Drainage P1An Submittal The items listed below are to be provided as a minimum with a road and drainage plan submittal. Additional information may be required to demonstrate that the plans meet all applicable standards. (13y checking "yes" for each item shoivn below, you are verifying Ihat these iterns have been conipleted and are included in this submittal. F'or any box checked "n/a a rvritten jzrstificatian of any omissions at the encl of this sectron is required.) ~ l.tem Description , S;es Road and drainage plans, two print sets. (Certification statEment on cover of plans) R'r yes 0 n/a One set of plans on 24" x 36" mylar media, or CAD electronic file --.DWG or.DXF fornlat IKy,ss Each Plan Sheet of record is signed and dated by the project sponsor. lryes The road and drainage design meets the requirements of State law, WAC 196-27 rcgarding "conformity with acceptetl standards"; that is, the design reflects the "state of the practicc" for the proposed concept. Ef' yes The plans, Drainage Report, basin map(s), and any other calculations are stamped, signed 0, mld dated by an engineer licensed in t11e Sta.te of Washington. I~ yes 0 n/a Drainage Report, two sets. To include: basin map(s), time of conccntration routes in basin map, and Certification statement on cover of report and basin map. . ~s Ul n/a Geotechnical Report, one set. (Include all soil test pit/bonng logs.) . yes 0pfa Structural Pavcment Calculations; one set 0 yes V n/a Cross-slope grade calculations for road widening projects. Item Description ♦ / 0 ycs fr ri/a Maintenance Manual and Sinlcing Flmd calculatiotis for drainage facilities locatcd outside af County road right-of-way. tJ ycs QK iVa Written explanation of who/what entity will be responsible for maintaining drainage facilitics which are located outside of public road right-of-way, and that the plan is acceptable to the , ~ County Engineers Office. 0' yes 0 nJa Channelization Pla.ii, or signing and striping in.fonnation p1-ovidcd in the road plans, To be included in road and drainage plmi set. 0 yes Vn/a I have read the Hearing Examiner's Report (lorlg plat), or Planning Dept. Findings and Conditions (short plat), for this project. The design meets the conditions in the report. 0 yes 0 y/a Copy of Approved Design Deviations. 0 yes Q"~a Fire District Approval, for private roads. 0 e ri/a y s Lot Alans. Requtred for any lots with dratnage easements and whlch front a public road, or ~ for lots which receive and treat runoff from a public right-of-way. 0 yes [V nia Any applicable State and Federal permits have been obtaincd. (i.e. HPA, JARPA, etc.). For Perrnits with conditions, 1 copy of the pennit and conditions are included in the plan f submittal. Vyes I s ~ n/a Inspection Agreement between the sponsor a.nd its engineer. 0 n/a For off-site easements to be ranted to S oka.ne Count the f 11 Nvin g n y, o o g items shall be included: legal description, exlubit, and proof of ownership. B'yes 0 n/a Erosion Control Plan, required for "Major Land-Disturbing Activity." To be included in the road and draulage plan sct. Explanation for any items listed above which are not included in this subnlittal: _ _ _ . . _ r . u.- - v- - ~ . , _ . . _ _ , - . _ _ . - ~ • . ' • . - . ~ - ' _ • - , (Note: an insufficifit jusU6cation of why an item ivas not included in the subnutted, or incomplete doctunents, may result in the subinittal being returned without review or wilhout acceptance. Provide attachments if necessary.) By signing below, the engineer is stating that the information provided in the submittal is complctc, thaC the information providcd in the Submittal Checklist is accurate, aiid the plans and calculations are in accordance with the Spokane Counfiy Standards for Road & Sewer Construction, and the Guidelines for Slormwaler Management, except whcre an approved Design DEViation allows othenvise. Engineer's Signature: Date: <:~9) P 2-~ Engineer's Name: (plcase print) / If there are any qzcestrons abozrt this far-rri or appi-opriate proceclut-es, please cnll I>evelopment Sefvices, Spokane County Picblic Works, at (509) 456-3600. Foi• Spokanc County Usc Only Submittal No: County Plan Reviewer: 0 Accepted in for Review or Coiistniction 0 RctuTTied to the engineer wittiout review andlor acceptance, See attached letter of explanation. Processing Date: SUb1111t(c11 CIleCkl1St Z Spokane County Public Works; April 29, 1998 Hemmings, Bill MNNNN~ From: Parry, Ed Sent: Friday, July 14, 2000 1:26 PM To: 'Atan Gay, P.E.' Cc: Hemmings, Bill Subject: BSP64 Alan: I looked over the revised basin map (your earlier e-mail) and tded to correlate it to the drainage calculations. It appears that there are now 2 basins on each of the north and south sides of the road: from station 1+91 (+J_ ) east to Sullivan, and from 1+91 west to the end of the cul-de-sac (on both the north and south sides of the road, for a total of 4 basins). I still have these questions: 1. riett width shouW1be,40' b.etween4Qe of curb (EngineeLC.aadi#GP=#~Staridard Plan #A1). Plans show o gutter ne. 2. ari tta b ~f-curb width~rtd~e ~,Re uir IA~vu+~l~-is-48(.E.~ineer~o~ibe~-#ror to 3beyond ur plans sof 65'. 3. Remainder of swale & sidewalks should be in a bortler easement to back of sidewalk. It appears that the stri between the curb and sidewalk should be a minimum of 101, as it is being used for tlrainage. ~ p ~4. How do the calculations show that easterly basin provides enough storage volume for the design storm ' event and enough volume for the 208 treatment requirement (V208 = road area * 112", swale floor area so V208 is \maximum of 6" depth)? Please note that if either the slope of the swales exceeds 1%, or the length of the swale ' exceeds 100 ft, then the swale volume needs to be adjusted as noted in the Guidelines for Stormwafer Managemenf. The width of the swale between the curb and sidewalk S. Do the plans take into account the fact that the drywell rim needs to be set at least 0.4' below either the invert of a curb inlet or the bank of a berm in order to develop the design flow rate into the drywell (with a safety factor)? This typically results in a floor elevation of 0.9' below the normal gutter line/top of berm for a swale with a drywell in it. What is the top of berm elevation at 1+81 ? AO . 6. Does any of the area from Sullivan Road drain into the s' e2_The-pxa rades and plan yaf= seem to di e tha ome po~i u' ains onto - i e. If so, the basin limits nee o e adjusted according y and shown o e Basin map. 7. Given our conversation of July 13th, it appears that the calculations should be revised so that infiltration is not considered as a disposal mechanism for the swales. Where the location is suitable for drywells, swale storage volume should be based on drywell ouiflow. I am enclosing a copy of the spreadsheet we use to evaluate drywell concepts. It may be of some use. If the theoretical Tc is less than 5 minutes, then the spreadsheet Tc defaults to 5 minutes to fit the I-D-F curve. If there is gutter flow, it will need to be adjusted until the values in cells Q14 and Q15 balance (approximately equal values for these; I wouldn't carry the value of "d" to more than 3 places right of the decimal). I will be out of the office until July 24th. Please contact Bill Hemmings if you have questions about the spreadsheet Ed FN f 53 V ~O-G,~ ~ 6 P age 1 gq,-o) mf a ~ ~~jina4 Q,~ ~ C~ Draf1- June 26, 2000 Definitions - Add to Section 1.02 " All-weather Road,,. . A road alignment, profile, and section that may not meetIr ~•03 standards for a Public or Private Road, but is still suitable for the expected emergency vehicle traffic and soil conditions. The road may or may not be surfaced with asphaltic ~,r►, ? concrete paving (ACP) or Portland cement concrete (PCC). The minimum traveled way ~ section shall consist of not less than 4" of Crushed Surfacing Base Course over a401 subgrade material compacted to not less than 95% of the Modified Proctor Value (per ~ ASTM Method or equivalent WSDOT Method. The subgrade shall be compacted to the specified value to a depth of at least 12 inches. "Sponsor": The party identified as the proponent of a given Land Use Action. The Sponsor is responsible under Spokane County Code for preparing plans for and constructing roads, accesses and drainage facilities in conformance with County Standards. The Project Sponsor is also responsible, where applicable, for the maintenance of those facilities "Final Approval": For Subdivisions, Final Approval of the Plat (by the Spokane County Board of County Commissioners) or Short Plat (by the Planning Department). ~ - For Commercial Projects, Certificate of Occupancy (by the Building Department Drc~, f't - June 26, 2000 Add to Section 5.01 - APPLICATION PROCEQURE The Sponsar, the Sponsor7s Project Representative, the County Engineer, and the County Utilities Directar shall execute the "Developer Agreement" prior to conduc#ing the Pre-Design Meeting or submitting any raad, drainage or sewer plans for the Project. The "Develaper Agreement°" shali be in a form acceptable to the Spokane County Engineer and approved by the Spakane Caun#yr Prosecuting Attorney. A sample "Developer Agreement" is pravaded at Technical C~ Qz~ Draft June 26, 2000 APPENDIX A CONSTRUCTION SURETIES FOR ROAD AND DRAINAGE IMPROVEMENTS The S okane Coun En ineer will acce t either Assi ments of Funds Letters of Credit or Bondin A h' ~ p ~ ~ , g Company Instruments to guarantee construction, inspection, and certification for Final Approval of the Land Use Action. The Developer is not required to post a financial guarantee prior to Final Approval. However, Final Approval will only be recommended if either the required improvements have been constructed by the Developer, and accepted by the County Engineer (to include Record Drawings), or if a financial guarantee acceptable to the County Engineer has been posted. 1. The Developer may utilize any one of the following methods to obtain Final Plat or Short Plat Approval A. POST SECURITY IN LIEU OF CONSTRUCTION BEFORE FINAL APPROVAL The SPONSOR may post with the Spokane County Engineer's Office a Financiai Guarantee for construction, inspection, and certification of the required road and drainage improvements in order to obtain Final Plat (or Short Plat) Approval. The Financial Guarantee shall be structured as foliows: ■ A Performance Retainer (in United States currency), of at least $7,500.00 or 10% of the guarantee amount noted in Block 4 on Page 1 above, whichever is greater, in the form of an assignment of funds, or Letter of Credit, naming the COUNTY as beneficiary, all in a form acceptable to the Spokane County Prosecuting Attorney. ■ The remainder of the guarantee amount noted i CB:4 on Page ].~~'ove, in the form of an Assignment of Funds, Letter of Credit, or Surety r_ff om a Bonding Company, naming the COUNTY as beneficiary, all in a form acceptable to the Spokane County Prosecutin~ Attorney. ■ Any security reductions, if allowed by the Spokane County Engineer, will not apply to the Performance Retainer. Security reductions will only be applied on Assignments of Funds or on Letters of Credit. ln no case will the aggregate amount of security reduction exceed the amount given by the formula: Total aggregated redaictiorr = 90% x(Total Surety - Retainer) Example #1: Total Surery = S100,000. Retairrer = 10 % xS100, 000 10, 000 as cash savings assignment or Letter of Credit; $90, 000 as cash savings ussignment, Letter of Credit or \ Bond from a Bonding Company. ~0•~ Total of reductions = 90/ x(100, 000 -10, 000) e*- ) = 90% x (90. 000 _$81, 000 total of all reductions. At least $19, 000 (S10, 000 retainer +S9, 000 other instrument) wi!l be held until the Counry Engineer accepts the construction certrfication Examvle #2: Tota! Surety = $50, 000. Retainer =$7500 (which is greater than 10 % xS50, 000) =$7500 as cash savings assignment or Letter of Credit; $42,500 as cash savings assignment, Letter of Credit or Bond from a Bondirrg Company. . Totul of retluctions = 90% x(S0, 000 - 7500) = 90% x (42, S00) _ $38,250 total of all reductions. At least $11,750 ($7500 retainer + 54,250 other instrument) will be held until the County Engineer uccepts the construction certification Page A-1 Dra, ft June 26, 2000 1Vote: Partirrl reductivns vn Bonding L'nmpany Surety Instrutnents will rrot he ullawerL Rer#ucti(o,rs in CaSII SeCuf[ly ft'Ifl I3e eOnS1deJ'L'f,I UltLy fDI pTUJ~~~s wlIicJlr il1 iJ1e C'Of1n1y Elt~',fJteet'S 0pLNlol#, are rnakfrrg stead,y progress, and.fOF wItlCh fJIe pIalT aCC~~ta1iCe ha5 Jiot e,Cp[l'SfI. ■ Final Release af the Financial Cuarantee {ta include the Perfarnnartce Retainer} will not occur until such kirne as the following actions have been cornpleted: l. All required impravements for the PAOJE.CT a,re constructed in accordance with the accepted plans on f le at the 5pokane County Engineer's Office; and 2, The SPONS4R's Engineer has submitted Certified Record Drawings and associated Inspectian Reports for the PRO.i'ECT (the "Certificat3on Fackage") to the Spokane Courtt}r Engineer; 3. The Spokane County Engineer has accepted said Certification Package; 4. The SPONSOR has posted a cash security or band for the warranty perrvd required fvr public rvad and drainage irnprovements, irn accordance with th~ edition of the Spokane County S1anc#ards for Raad and Sewer° Construction (the "Standards") applicable to the PROJECT; and 5. The Spokane County Buard of County Cornmissioners has acc.epted the public raads and public drainage faciCities for ownership and rriaintenance. ■ The S.PONSOR's obiigation ta perform work and pay fees and ather amounts is not limited to the arnount of the associated cash security or band. B. PARTIAL CON5TRUCTiON BEFO1zE FtNAI, APPRQVAL The SPOA1SOR may chaose to construct a portian of the required road and drainage irnprovements in order to obtain Final Land Use Activn Appeoval. The SPONSOR understartds that ■ The County Engineer will accept anly a cash savings assignrnent as security for the pvrtion of #he PTtOJECT that has not yet been constructed at the time Final Approval is requested. The a.mount will be recalculated from the ortgiii$1 surety +estimate, ta account for such elements as changed quantities, revised unit prices, eonstruction of the reiiiaining work through Public Wcarks contt'ac.fiijlg procedures, project inspection and certif`ication, etc. ■ Final Approval wi13 not oceur until such titne as: ■ The SPONSOR's Engineer nas subrnit#ed Certified l~ecvrd Dravvings and associat~ed Inspection Repvrts for the PROJECT (the "Certific.ati€an Package") ta the Spokanc County Engineer for the consiructed improvements; ■ 7"he Spokane Caunty Engineer has provisionally accepted said Certiicativn Package; and ■ The SPDNSOR has posted a ca,sh security for any retnaining road and drainage impravements (Pubiic or private), irr ac cordan ce w ith the edition af the Spokane Count}+ S'tarrdardsfor Road and Sewer Corrstrucliun (ttie "1JdCInLLQYC.t.S") applicable to the PRQJECT, and t-he accepted plans on f 1e at the Spvkane Caunty Engineer's Office. As a rninimurn, the S'PDNSOR shall post the Performance Retainsr, based on the original quantities shvwn on the approved and accepted plans on file at the County Engineer's Dffce, as amended. lYvre: 7`he cash securitv for this aption shall be in the farm of a cash savings assignment and in an amount as estimated by the County Engineer. The financial guarantee shall include a "date certain" for completion caf the rernaining wark. The "date certain" rnust occur prior to the orig'ma] expiration date of the plan acceptance. The financial guarantee sha11 include a provision t}tat failure to obtain the Count}r EngineeE's acceptance of the rernaining work by the "date cercain" sha11 constitute a rnat;erial hreach, and shall be grounds fvr immediate demand by the Spvkane County Engineer f.ar full payrnent of the entire amaunt of aIl financiai guarantee instrurnents relevant to this PROTECT. The proceeds of the financial guarantee shall be used by the County Engineer to camplete the remaining work. t3►ny surplus shall be refunded to the SPONSOR upon the County Engineer's acceptance of the ccampleted wark. The SPQNSOR shall reimburse the County Engtneer's C)ffice for any costs in excess of the amount of khe total arnaunt of the financial guarantee incurred by the Caunty, includinla but not lirnited tc] Cpn5truCtiDn, irispecirQn, administr'ation, collection agency fees, and legal expenses ineurred in securing the financial guarantee and completing xhe work. Page A-2 Draft June 26, 2000 C. COMPLETE AND CERTIFY CONSTRUCTION BEFORE FINAL APPROVAL The SPONSOR may choose to construct all of the required road and drainage improvements in order to obtain Final Approval. The SPONSOR understands that Final Approval will not occur until such time as ■ All required improvements for the PROJECT are constructed in accordance with the accepted plans on file at the Spokane County Engineer's Off3ce; and • The APPLICANT's Engineer has submitted Certified Record Drawings and associated Inspection Reports for the PROJECT (the "Certification Package") to the Spokane County Engineer; and ■ The Spokane County Engineer has accepted said Certification Package; and ■ The SPONSOR has posted a cash security or bond from a bonding company to warcanty the construction and materials for any required public road and drainage improvements, in accordance with the current edition of the Spokane Cnunty Standard.s for Road ancl Setiver Constrzrction (the "Standards"). The term of the cash security or bond shall be for two years . 2. Reductions at time of Substantial Completion ("Punchlist Bonds") are addressed at Attachment A-1 Page A-3 DRAFT - Juire 26, 2000 ATTACHMENT A-1 , CONSTRUCTION SECURITY AT SUBSTANTIAL COMPLETION The County Engineer may, at his discretion, further reduce the Plat Construction Security prior to Final Acceptance of the improvements and Final Plat Approval. This will only occur when the County Engineer determines that the improvements are "substantially complete". "Substantial completion" shall mean that the required plat improvements meet these conditions: Spokane County and/or any applicable Homeowners' Association must have full and unrestricted use and benefit of the facilities, both from an operational and a safety standpoint. The facilities must conform to applicable Spokane County Standards Only minor, incidental repair work, replacement of temporary substitute facilities, or correction or repair work remains to reach physical completion of the work. If the work is substantially complete, af:d a Cash Security (Assignment of Funds or Letter of Credit) has been posted for the plat improvements, then the Cash Security may be further reduced to twice the estimated cost for Spokane County to complete the remaining work if a "date certain" (considering weather impacts) is established. The amount of the Cost Estimate shall be determined by the County Engineer. . Once the Substantial Completion Financial Guarantee has been posted, the County Engineer may, at his sole discretion, recommend Final Approval to the Board of County Commissioners. The Board of County Commissioners is not legally bound by the County Engineer's recommendation. The County Engineer's recommendation is not to be construed as a guarantee or warranty of any sort that the Board of County Commissioners will in fact grant Final Plat Approval. This option will not be available to the Developer if: The current amount of the Cash Security (in excess of the Performance Retainer) is less than twice the estimated cost of completion A Bonding Company Instrument has been posted An initial Construction security has not been posted for the project (Scenarios "B" and "C" noted in Appendix A) The Sponsor has existing projects that have not been completed prior to the expiration date of the plan acceptance for the current phase APPEND1X B CONSTRUCTIOIV SURETIES FOR SEWER YMPROVElVIENTS The Spokane County Utilities Division vvill accept either Assignments of Funds, Letters of Credit, or Bonding Company I«struments with language on1y as appraved by the Spokane County Prvsecutor's Office to guaranxee construction for Final Appraval of Land LTse Actions. Any Surety submitted with language other than Nvbat is previousEy approved wiil be subject to review by the Prosecuting Attorney's Office. A. For Plats, Short Plats, Qr other land use actions requiring Rublic sewer collection system final approval will anly be recomrnenderl if either ttae required improvements have been construcfied by the Developer, accepted by the [Jtilitzes Division (to iiiclude Record Drawings), and secured a# the warranty arnount, or if a financial guarantee acceptable to the Utilities Director has beert posted. l. IfPublic off-site Sewer Extensiam is not reyuired. The Developer shall post a financial guarantee equal to the amount estimated by the Utilities Departrraent for the an-site sewer improvements, prior to Fi»al ApProvai. 2. ifFublic ❑ff=site Sewer Extension is required: The Develaper shall post scparate financial guara.ntees equal to the amount estimated by the Utilixies Division for the on-site sewer ii-nproveTtients and for the off-site extensiQn, prior to F'inal Approval. Whem the canstrucfiion has passed the air test and mandrel test, the guaran#ee rnay be reduced to 50% of the initial arnount. When the Ut%lities Divisinn has accepted rhe sewer constructian 'for aperation and maintenance, and Record Drawings have been approved, the guarantee may be reduced to 25% af the inikial amount. This 25% will be held as securrty far fihe duratyon of a, warranty period. If either of the ini#ial guarantee amounts exceed 00,000, then t.he secur`rty will be 2(}°lo af the respecfiive rnitial arnount. B. For Commercial ProJeets: l . Private Sewer SysteFn: IVo fnancial guarantee is required for private sevver systems. Plans must be submitted to the Utilities Division and accepted for canstructian prior to issuance of a 5ewer Connection Perrrrit. Inspectinn o-f sewer construction rriust also be scheduled thraugh the Util'eties DiviSion. 2. Public Sewer Extension required: Afinancial security, acceptable to the County Utilities Director, musk be posted priar to sewer construction plans beirag accepted by the Utilities Division. Sewer connection permits will he issued only when the Utilities Division has accepted the sevver extension construction far aperativn and main#e«ance (subject to aone year vvarranty period) and record drawings have been approvede Page B- l DRAFT - June 26,2000 . m - ~ ` SPOKANE COUNTY D~PAR,T11ENT OF PUBLIC WORKS ENGrNEERTNG AND R.OADS DIVISrON 1026 W. Braadway Ave. Spakane, WA 99260 DEVELOPEI~ ~GREEMENT - PLATS/SHORT PLATS 1. Preliminary Platl.Permit Number and Narne: 2. AGREEMENT Number 3, 5pansor°s Name and Address: 5. Sate LocatianlSeckion-Range-Township: This AGR-EE1VlENT is made and entered into this day of , 20 , by and betwveen Spokane County, a political subdivision of the 5tate of Washingtan, having o-ffices for the transactian ❑#`business at 11 16 West Braadway, 5pokane Washington, 99260, hereinafter referred to the COUTVTY, and , having offices for the transaction of business at hereinafter referred to as the SPONSOR, and jointly refereed to as the PARTIE8. All references in this AGREEMENT to the SPONSOR sha11 include the S.PONSOR and its heirs, successors and assigns. A11 references in this AGREEMEN'T to the CO[JIVTY shall include Spokane County and its successor political jurisdictioros. Wi''NESSETH VVHEREAS, SPC}NSOR's Prelimanary Platl 5hort Plat Na. {hereinafter ref+erred ta as the <`PROJECT"}, containing various canditians of approval impased pursua,nt to RCW 58.17 and the Spokane County Subdivision Ordinance, was approved on ; and VVHEREAS, the SPONSOR seeks to have the road and drainage plans required for the PROJECT approved by fihe SPONSOR's Engineer and accepted by the Spokane County Engineer; and WI-IEREAS, the Spokane County Engineer will accept the road and drainage plans for tlle PROXECT upan the SP4IVSOR's successful campliance wizh this Agreement and all conditions of approval, Spokane Caunty Gode, other Codes and regulatt'ons, and other conditions of any Design Deviation Request Approval as deemed necessary by the Spokane County Engineer, applicable ta the PROJECT; and Page I of 8 ~ DRAFT ~ ~ - Dk4FT - June 26, 2000 ' WHER:EAS, the Spokane County Eng%neer is authorized under the provisians af Spokane County Code Section 9. ] 4.D40 to require the posting of a surety or 6pnd to (a) gedarantee the performance af conditions imposed vn various Land Use Actions, and {b} to warranty the quality af wQrkmanship and materials in al1 rc►ad, approach, and drainage facility construction required hy said Sectian 9.14; and WHEREAS, this AGRIEENfENT is interaded tv clarify variaus elements of policies of the Spokane County Engineer's ~ffice, and #o bring to the attention ofthe PARTYES variaus requirements of Spokane County Code and other regulations applicable to the PROJECT; and WHEREAS, pursuant to Resolution No. , the Spokane County Board of County Commissiotiers have authorized the Spokane County Engineer and the Spaka.ne County Utilities Directior to eriter into Agreei-nents with Praject 5pans[rrs, in which various clements of palicies of the Spakane CC1UI1ty EI1g111eeI''S Office, and VaI'10U5 requirerrsents af SpQkane County Code and ather regulativns applicable to various Development Projects are clarified, NOW THEREFORE, the SPONSOR hereby agrees and binds itself and its legal representatyves, successors, and assigzis, as follows: TERMS OF TE-fE AGREENiENT. This AGREEMEtvr is not to be construed in any manner whatsoever as a waiver of any Condttions of Prelim inary Plat (or Short Plat) Appeoval, S pokane County Code, other Codes, statutes ar regu lations applicahle to the PROTECT. Sueh provisions shall cpntintie tQ apply with full force and effect, in addition to the terrns of this AGU~-~MENT. 2. The SPOIVS4R shalrt fulfill all conditions afappraval ofthe PRO.TECT, and all other requirements of Spokane County Cnde, other Codes and regulatians, and ather e4nditians of Design Deviation Request Approval as deemed necessary by the Spokane Couiity Engineer, applicable to the project, even if these requirements are iiot set forth in this AGR,E_Emr~NT, 3. The SPONS4R has completed the attached "AGREETViENT TD PAY FEES". These fees are separate fram any ather Planning oe Plat Review.Fees related ta this PRDfECT. `["he SPONSOR shall reimburse the COL]NTY for all direct and indirect costs incurred by Spokane County related ta this PROTECT. Payment of said costs shal l be in accordaI7ce wcth the attached "AGREEhMNT TO PAY FEES" farm, Wl1Ech is made a pai'# of this ACREEMEN7` by reference. if the SPONSQR daes not submit payment far said fees in accordance wi#h the terms of the at#ached fiAGREEMEN'E' TQ FAY F.EES"T the SpoEcane County Engineer's Office may suspend plan review, and/or withhold plan acceptance on this PROJECT, uFith ar without natice, until overdue reimbursernents are received at the Spaka,ne County Engineer's O.ffrce. All fees rnust be paid before Final Approva1 is given, or any bands are released a# the conclusion of the project. 4. The SPQNSOR ,hereby designates , whose adclress is and whase telephone number is or , as the PROJECT REPRESENTATIVE for this project, who sha11 be ernpowered ta act within the scope af his or Iier respansibilities as defined hereioi, for tl~e undersigned SPOIVSUR. It shall be the PRQ.IECT REP.RFSENTA7'IVE'S responsibility ta ensuee that the Developer's project tirneline is met, through comiiiunicating arid coordinatin~ betw~een the Developer7 tl~e Design Engineet, Fage 2 of 8 DA4 FT i ' DRAFT - June 26, 2040 ' and the Caunty, to ensure that all Design Standards and submiCtal reqtiirements are, clearly understoQd and met. The PROJECT REPRESENTATIVE is the primary cantact person betvveen Spokane County and all other pa.rties who rnay need to provide services tovvard the suceessful completion af this Project. The PROJECT REPRESENTATiVE's respansibilities shall include, 6ut not be fimited to: a) Project coardinatian & communication to ensure that the profect moves forward in a timely maiiner, from Fraject Applicatron through Construction Compietion; b} Oajectively informing the Deve3oper of the project status, and potential prablems, and warking with the agplicable parties #a anticipate and resolve grablems; c} Ensuring that the Developer's Engineer coordinates construction plan changes for approval thraugh the Cauniky Engirreer's Office, prior to impleinenting the change in the field as much as possibley d) Coordinating inspection report submittals, construction close-out, banding issues, constructian payments, and certi-fication, up ta and including acceptance of Record Drawings tiliraugh Final Warranty Surety Release; c) Caordinating respanscs to project-related questians or infarmatian requests frvm the CpLLnty Engineer's Office; ensuring that #he Traf~ic Contral Plan is being followed by the Contractor; g} coordinaking neigliborhood notifications, and h) resalving canstruction cornplaints . 5. Priar to beginning desigii, a pre-design conference shall be held between Che COUNTY, the SPONSDR, the SP4NSOR's Project Regresentatsve, and the SPONSUR's Engineer. If the PR[)JECT is located in a{CitylCounty Join# Planning Area, a represeiltative of the Spokane City Engineer may a[so attend. This conterence rs an avoort:utii~~v for the SPONSOR t;o raise a~iv auest,rons abOLit the Gountv's Deskm 5tandards. Canditions oF Approval, or administrative items. The SPONSOR is encauraged to submit questions in writing priar to the conference far consideration at the conference. b. Prior t-o submittal of any design documents, a px-e-submitkal meeting must be held between the Developer, the T)esign Engineer, and the County Etigincer's Office, to ensure that Design Dncuments ' conform to the applicable County Standards and the ConditiQns of Approval. Incomplete Design Documents should not be apgroved by the Sl'ONSOR"S Eng,aneer and should nat be submitted ta Spakane Caunty for Acccptance, [f the,Design Standards are clearl}+ unders#ood and me#, and if all subrnittal iterns necessary to furm acomplete and approved submittal are included, then it is possible for a given project to abtain Canstruction Plan ar Record Drawing acceptance from the County with a minimutn af resubmittals. Priar to beginrtirtg constructiora, a pre-constructian con#'erence shall be held betweert the SPC11VSOR, the SPONSOR's Praject Representative, the S.PONSOR'S Contractor{s} and the SPONSOR's Construction Engineer. A copy of tlle conference rninutes sha11 be pravided to the County,Engineer's Office as part of the canstruction docutnents. S, The SPONSOR must submit to the Spokane County Engineer, and the Spokane County Engineer must apprave in writing, any major changes from the appraved plans propnsed by the SPO1rTSOR, prior tn beginning such work in the field. 1Vfinar plan changes are to be documented in the Project Inspectron Daily Reports and Project Summary Reparts, which are to be submitted an a weekly basis to the County Engineer. The County Engineer urill utilize a"fast-track" system to process changes when time does not allaw far processing plan changes in the standard fashion. 9. The SPONSOR shall be responsible for costs afan}r carrective work (construction or warranty) an or off the site to the extent that such corrective mea.sures are associated with work perfacmed and/ar not completed pursuant ta Spolcane County Code Sections 9.14.030, .040, .050, .2001.250, and athers as may be applicable, Page ~ a f S DRAFT i DRAFT - June 26, 2000 10. The SFONSQR sha11 implement all necessary erosion-seditnentation measures/facit'ities to ensure sediment-laden water does not enter natural or hurnan-made drainage facili#ies and will maintain them until such time as erpsian pote,n#ia] has passed pursuant ta Spoka.ne County Baard of Caunty Commissioners Resolution TVo. 98-0201, as amended. In the event erasion and sedimentation is observed and upon written notice by Spokane Caunty, the SPONSOk shall immediately take carrective actions ta prevent ervsivn an or off the site pursuant to said Resolution 98-0~0I, as amended. 11. Prior to a recammendatiori of F'inal Land Use Approval by the County Engineer, the SPDNSOR may, at the County Engineer's discretian, post a finarrciai guarantee in xhe amount noted in Black 4 on Page I abave to guarantee construction, inspection, aiid certification af the road and drainage improvernents cequired far the PROJECT. The financia[ guarantee shala be rn a form approved by the Spokane County Prosecuting Attomey and in an amount acceptable ta the County Engineer. The financial guarantee shall remain in full fnrce and effect unless and until specifically released in writiiig, or atherwise modified by #he Spokane Courtty Erigineer. All financial guarantees must include a provision that they may not be cancelled or otherwise impaired unless the Spakane Coun#}r Engineer has provided expressed Nvritten consent #o t.he proposed canceliation or other impairenent at [east 30 calendar days prior to the desired clate of cancellatioro. All financial guarantees must also include a provision that a notEce of cancellatian or ather impairirsent, or a failure to maintain a financral guarantee as agreed upon herein shall constitute a mater'ral breach and shall be grounds for iinmediate doinand by the Spokane County Encrineer far full payment of the entire arnount of all financial guaraiitee instruments relevant to this PROJECT, subject thereafter to revision or refund as may be determined appropriate by the Spokalie Caunty Engineer. 12. Prior to a recammendatian of Final Land Use Approval by the County Utilities Director, the 5PONSOR may, at the discretian vf the County Utilities Director, post a financial guarantee in the amount noted in Block 4 on Page I above tv guarantee constructian, inspectian, and certification of the sanitary sewer impravements required for the PRDJECT. The financial guarantee shall be in a form approved by the Sgokane County Prasecuting Attorney and in an amount acceptable ta Caunky Utilities Director, T~e financiai guarantee shall remain in -full force and e-ffect ur,less and until spec~-fically released in writing, or ntherwise modified by the Spnkane County Utilities I7irector. All financaal guarantees must include a provisian that they may nnt be cancelled or otherwise impaired unless the Spakane UtElities Director has provided expressed written cansent ta xhe praposed cancellation or ather impairment at least 30 calendar days priar to the desired date of cancellation. All fcnancial guarantees rnust aiso include a provision that a notice qf cancellation or other impairment, or a faiiure ta maintain a financial guarantee as agreed upon herein shall constitute a material breach and shall be gruunds for immediate demand by the Spokane County U#ilities .Director, far fu1l payment of the entire amount of a11 fnancial guararrtee instruments relevant to this FROJECT, subject therea.fter to revision or refund as may be determined appropriate by the Spokane CoL111ty UC111t1e5 DlF$CtOF. 13. The SPDNSOR hereby grants the COU'NTY and its o-ffieials, employees, and agents the right to enter and inspect the praject site, and, in the event of any failure to perforrn terms of this AGREEMENT, to implement such corrective measures as the COLTNTY deems necessai-y. 14, The SPONSOR agrees not to begin constriiction of any af the road or drainage improvements for the FROJECT, ❑r nthenvise disturb the PROJECT site, until tl$e canstruction plans for sarrie Iiave heen accepted by the Spakane Counfiy Engineer -for constructian, and a germit has been issued far said Page 4 af 8 DRAFT i ' 13RAFT - June 26, 2040 construction by the Spakattle Caunty Engineer, pursuant to Spokane Coun#y Code Sections 9,14,080, .110, .23{], and ather sectians as may be applicable. 15. The SPONSDR agrees and covenants that all of the road and drainage construction for the PROJECT shall be campleted no later than two (2) years from t.he date af the Spokane Cauntiy Engirreer's plan acceptance. If constructivn is not camplete on the said date of comple#ion, the SPONSOR will be in default. If SPDNSOR is in default, Spokane Caunty is authorized to call upon the finaiicia1 guarantee in accordance with the ten-ns and conditions of the finaiicial guarantee to complete the improvements that are covered by saici financial gua.ra.ntee. Any failure on the part of the SP0NSQR to proceed with due diligence and in good faith in the canstruction, maintenance, andlar monitaring work provided herein shall, upon written natice by the Spaka,ne County Engineer, con,stitute a default of the terms af this AGREEMEN T. 16. The SPONSOR shall be respansihle for tlle praper perfarmance, safe conc{uct a.nd adequate palicing and supervision of the project. This respansibility sliall not be lessened or otherwise affected by #he COLJ-NTY's review of plans, specifications, or wark, or by the presence at the wark site af the CC1LTNTY's representative(s), vr by the compliance by the SPONSOR with any written ar verbal requests made by said representative(s) (e.g., "punchlists", memoranda, ar ather communications). l?. This AGREEMENT shall rernain in effec-t and any applicable associated financial guarantee (Warraiity Surety) shall not be released until the applicable warranty period has expired. 18. 3"he SPONSOR shall indemnify and hvld the COLTN~.' and its agents, employees andJor afficers harmless from and shal] prQCess and defend at its own expense all claims, damages, suits at law or equity, actians, pertalties, losses, or costs of whatsoever kind ar nature, brought agains# the CQIJNTY arising out of, in cvnnectian with, or incident ta the execufiion of this AGREEMEIV'T andlor the SPONSOR's performance or failure ta perfortn any aspect of the AGREEMENT. Provided, hawever, that nothing herein shall require the SPONSOR to hold harmless or defend the CO'U'N`CY from any cIaim arising fram the sale negligence of the COUNTY"s agents, employees and/ar ot'ficers. 19. In the event #hat any PART'.' to fihis AGREEMEIVT deems it necessa.ry to institute legal action or proceedings #o enforce any right or obligation under this ACREEM.ENT, the PARTIES hereto agree that any such action or proceeding shall be brought in acourt of cnmpetent jurisdiction situated in Spokane County, Washington. 20. In the event that any portion afthis ACtREEMENT may 6e held to be invalid by a cvurt of campetent jurisdiction, all ather portions of this AGREEWNT not held to be invalid shall remain in full fQrce and effect, and the AGREEMENT shall be rnodified accordingly to the mutual satisfactian of the PARTTES. IN WITNESS TIFIEREQF, the parties heret-o have executed this AC'iRLEM'ENT as of the day and year first above uTritten. (Select tlze signature hlock(s) as appropriate) SPONSOR: (1) For an acknowledgement in an individual capacity Page 5 af 8 DRAFT ' DRAFT - June 26, 2000 (NAME) State of Washington ) )ss County of Spokane ) I certify that I know or have satisfactory evidence that (name of person) is the person who appeared before me, and said person acknowledged that (he/she) signed this instrument and acknowledged it to be (his/her) free and voluntary act for the uses and purposes mentioned in the instrument. Dated Notary Public in and for the State of Washington. My AppointmentExpires: (2) For an acknowledgment in a representative capacity: CORPORATlON NAME A Washington Corporation By: (NAME) Its: (TITLE) State of Washington ) )ss County of Spokane ) I certify that 1 know or have satisfactory evidence that (name of person) is the person who appeared before me, and said person acknowledged that (he/she) signed this instrument, on oath stated that (he/she) was authorized to execute the instrument and acknowledged it as the (tvpe of authoritv, e.e.. officer, trustee, etc.) of (name of party on behalf of whom instrument was executedl to be the free and voluntary act of such party for the uses and purposes mentioned in the instrument. Dated Notary Public in and for the State of Washington. My AppointmentExpires: FOR ACKNOWLDEGEMENT OF PROJECT REPRESENTATIVE'S DUTIES PROJECT REPRESENTATIVE: Page 6 of 8 DRA FT ' DRAFT - June 26, 2000 (1) For an acknowledgement in an individual capacity (1`IAtvE) State of Washington ) . )ss County of Spokane ) 1 certify that I know or have satisfactory evidence rhat (name of person) is the person who appeared before me, and said person acl:nowledged that (he/she) signed this instrument and acknowledged it to be (his/her) free and voluntary act for the uses and purposes mentioned in the instrument. Dated Notary Public in and for the State of Washington. My AppointmentExpires: (2) For an acknowledgment in a representative capacity: CORPORATION NAM_E A Washington Corporation By: (NAME) [ts: (TITLE) State of Washington ) )ss County of Spokane ) I certify that I know or have satisfactory evidence that (name of person) is the person who appeared before me, and said person acknowledged that (he/she) signed this instrument, on oath stated that (he/she) was authorized to execute the instrument and acknowledged it as the (tvpe of authoritv, e.2., officer, trustee, etc.) of (name of nartv on behalf of whom instrument was executed) to be the free and voluntary act of such party for the uses and purposes mentioned in the instrument. Dated Notary Public in and for the State of Washington. My AppointmentExpires: Page 7 of 8 DRAFT ' DRAFT - June 26, 2000 SPOKANE COUNTY ENGTNEER'S OFFICE By: William A. Johns, P.E. Title: Spokane County Engineer Date: SPOKA.NE COUNTY UTILITIES By: N. Bruce Rawls, P.E. Title: Spokane County Utilities Director Date: Page 8 of 8 DRA FT v G~FFICtAI PU6LIC DQCl~tJ~NT SPQ~~~E JUL'N i~Y ENti!~iEEF~'S UFFICE OR A~ PRO,{ECT # :$~>e G4; SUDt-v1I1TAL # ~5 . Drainage Report, R.A. Bonucce--i RETURN Ta ~UNrY ENGINEER Marietta at Su----I*van Deve-.opment RECEIVED BSP-64-98 Spokane County, Was--iington SPO,E~~ . ~~~~~~~~omp Stateme n The following report was prepared under my direction. The contents are engineerulg opi.nions derived using procedures that meet industry and professional standards. This document was not prepared as a construction document. Alan E. Gav Professional EnRineer Printed Naine Title Civil Engineer AuLyust 2, 2000 Date E. Qells v,Asy~'~~- . c- t- ~ 2Si 94 C7~ EC,j$i'~RR~ . SfaNAL EXPIRES '1'ECHCOV, InSC. Professional Engineers • Certifieci L+'iivironmental Specialisls • Yroject Managers • Sfeel Detailers t ~ U1tAINAGE R:CPORT ROBERT A. BONUCCELLI NIARIETTA AT SULLIVAN INDUSTRIAL DEVELOPMENT SPOKANE COUIe1TY, WASHINGTON Proposed improvements to the site at the extension of Marietta Road west of Sullivan Road, trigger the need for stornl water runoff disposal improvements by Spokane County regulation. The calculation sheets following this narrative include details of the analysis showing that the proposed drainage improvements are adequate to control runoff on the site for a 10-year event, and safely discharge runoff for larger events at a rate equivalent to or less than the discharge rate in the pre-developed condition for the site. Key assumptions made for the site include assuming that the soils are Garrison gravely loam and Garrison very stony loam with an effective penncability equal to or greater than 0.36 inch per hour (0.36"/hr.). Another key assumption is that the intensity-duration-frequency (ZDF) curves for the site confonn to the IDF curves for Spokane as published in Chart 34 of the Washington State Department of Transportation (WSDOT) Hydraulics Manual. The drainage areas in the development are designated by parcel and roadway. Parcel basins are shown as Parcel 1 through 9, with Parcel 4B being held in reserve. Drainage submittals for Parcels 1 through 9 will be made at the time of application for individual site building pennits. Parcel 4B may or may not be used for drainage for one or more of Parcels 1 through 9. Roadway basins are designated as Marietta West, Marietta Middle and Marietta East. Each of these basins includes mirror image basins on either side of the Marietta centerline. The Marietta Middle basins drains into the Marietta West basins, effectively making a total of four basins. These drainages are shown with these designations on the drainage and grading plans presented with this report, as well as the times of concentration for Marietta West, Marietta Middle and Marietta East. The Bowstring method was used to assure that the roadside swales will have adequate volume to ; contain a ten year storm event ~ The existing hydrologic conditions for fihe site are undeveloped. The calculated peak runoff for the existing site, using the SCS method, follows: Q=(P - 0.25)2 / (P + O.SS), where: Q= runoff in cfs; P= total storm rainfall, S= potential abstraction in inches S= l 000/CN -10 CN = curve number In this case, the CN = 70, since the soil group is Garrison, an "B" hydc•ologic soil. The land use is approximately the saine as pasfiure in fair condition, thus the 70 rating. S= 4.29 P= 3.04 lI1CllES lIl 24 hOU1'S fOT a 100 year storm. 4 t Q= 0.737 inches over the site. Thc site drainage basin is approximately the 19.3 acres of the sitc, since the di-ainage is bounded on the west by the old Coininco property, which slopes to the west, the north edge of the site is the Johnson Mathey property with its own hydrologic controls, thc south edgc of the site is the old Milwaukee Railroad right-of-way, and drains toward the south, and the east edgc is Sullivan Road. Therefore the total pre-developed runoff from a 100 year event is preciicted to be 620,000 cubic feet. For the peak runoff, the hydraulic length is 1234 feet, which equates to an equivalent area of 19.3 acres. Using the Type 11 stonn curve, the estimated peak runoff for a CN70 is 11 cfs/in of runoff. This equates to 8.1 cfs allowable peak runoff.. For a 10 year storm, P= 2.12, and Q= 0.287 inches over the site; therefore the allowable peak runoff is 3.16 cfs for a 10 year storm. The predicted peak amount is 0 efs for the SW and SE basins, unless a runoff-over- ice condition develops that fills over 7000 cubic feet of storage, in which case up to 3 cfs would be discharged through the overflow pipe in the southwest comer of the SW swale. SLOPE \ i ~ yq. t~* SiOEwa1,K ~ TO DRAIN ~ TO SWALE BE7vEEH ~ ROAOWAY ac SipEWALK ` t 13.26 \ „ TC 1998.75 'L ~l 1998.25 Cl EL. \ ~ x \ A X 98.0 ,X I999.6 ~ _X- w IR GA71ON SERVICE L- 185 tF ~I + 13.7 7 W/ METER AND Al1LMATIC G e 0A24 _L. 1998.4q j ~ CONTROL, 1AY0UT • CRASS AS At,T ~ I ` LANOSCAPING INSTALLE CiiANNEL "`^•FiN1S ~ \ EE 0£Teul EL. El 149 0 6 1998.65 ~ wES7 En+O \ MARIETTA - \ 1-69 LF, G 0.0 9 CRASS CHANNEI. SEE dETAII 5/4 ~ BASlN G EL. \ ~ WEST MARIETTA i" NtATER RvICE \ El. 1997.0 ROnOStO SWALE StUB. - TOTAL AR • 602 S.F. I' ~ETER, GaTE vaLVE (TYP EAC ~ BOTTO+~t E~ 19 ~ 27 , 9 i8 3 1 STA 0+64.4 CURB PT STA i+- D SiA +66.a8 ~ ~g+, 3 ~ S. aFFSE-T 20.58C, - • . 1996 N. OFFSET 20.5 ( kC) \ CURH CUTS ('2-) ~,ATA ~ti A STA 0+61 I I \ Oa' LONC S. OFfS£T 23 5' ~ ~ r e.L. 11 99 3 o ~ TC=8C 1997.79 i N. OFFS£7 23.5' 5 E E O E t a L 117 a E{. ~ o o: O R Y W E L L R i l A E l. 1997.77 ~ ~ S tA 731 SEE 0£ Tail 15/4 \ ~ S.\OffSET 20.5 (TBC) ` StA i+ 0_, D (TYPICAL OF 2) N. OF SET 20.5 (T8C) ~ TC 1 20 STA 0+67; TOP OF BERM EL 1998 9 ~ URB CUTS (2) 6ERM BETWEEN LOwfR, \ ` \~4' LpNC ~ \ ~ • ~ n~i ` wEST END SWALE I~ND . CL EL. iC-B 2001.00 MIDOLE SWALE (TYP OF 2) 200°~•3 m~,.~e~,aooSE€~o~.TA~~Z~~od~•o ~ ~ _ =moo ~°aqooooooaQOO~.6.oooe~ ` - 00.~- 4 \ LOOLE MARIETTA ~ - tN su + & RO'AQ OE StYaIE \ STA t+9t 2 e.\ `OTnLEn 456 S.F. S. OffSET 23.5' ~ stA X 60TTO~EI 5 O~0 \ N. OfF5E7 23.5'~ `1 a ~ DRYwELL~RIM EL. 2001.54 ~ AT G=0.03 ~ ~ 9C ~ ~ /J 1-0 c.uc?~T ~'~'/1h~/~/?.~r 5£E~OE Y~ TtiLOF 2} ~ ~~+g ° 5 Ar rG ~ , L. r- \ HERM SETM'EEN LON~ER, ~ \ r~ 3• w'EST ENp SWALE nN0 \ 1 11 ° MILDOLE Swna.E (TrP OF 2) \ TG t~/ f 1~~ r ,CRES $TA 1 \ ` 1 ` T l. ?(1 N., \ STA t+ - ~ EAST-XJARtffiA ~ -,C ~ zo ~5. ROO.O5I0E SWALE ~ TOTAL AREa 1200 S.F, • ` ~r ~ C \E ' (TYP EACH SID£) Z ~t~1 1 2 80TTpN EL. SLOFEO STA 3+73.3"'\ To 1 20-S •II AT G-0.03 +a $ pfF$£T 20 5' (TBC) ~ tG t SiA N-,,OfFS£T 20.5' (TBC) ~ 3' wsOE Swnt.£ BOT iQ►n ,,WRB CUTS (2) ~ tC E i ~ (TYP) A 4' IONG TC~@C 2007.10 STA ~ 2 SEE OE~AIL 17/4 f. 7 - O O - d m O - o o G m o O m o o \ o G o o v cS-- Ci o o O o O O O o m a C+ o 0 o O C~ n c.~ GY O G-0 9- 0- C~ - ■ I a.m o o c^~ _rT- q x Cl EL. _ 0 0 EL. 2008 9 2008.1 ~ I A EAST ENO TA MARIETTA \ ' ~ \ ~ - - BA$IN i I 0 ~ ~ LaucsCape S£T$ACK ~ ~ J ~ (TYP) i 'L EL. ~ f F2009. SEb'UER EASEMENT RI ~ ~ . ~ \ u ^ ` - - .".b-EL - _ - - - - - - - - ~ _ ~ ~ - - - - - - - - - - - - , - - - - - - - - _ • t ~ # 94~ ~1901,5 ~ - ~_~---~-~--~---~-~----~----p----~----- - 1, G- - - _ _ , _ J~-~ ~u~aEDU ci ciaooooCA aczi C71 ooonooc~ Bonuccelli Development Marietta & Sullivan 11-Ju1-00 Stormwater Disposal Entire Site is One Parcel Drain to Intlividual Parcel 208 swales ' Areas Required: Resulting Landscaping Area: TOTAL TOTAL NET NET MAX. UNBUILD- MIN LOADING REQ. Sublot # Type III Type IV AREA ACRES AREA ACRES BUILDING ABLE PARKING DOCK AVAIL? SWALE Imp.Area acres 1 2892.5 0 83135 1.908517 80242.5 1.842114 32422.65 44094,76 1800 OK 6158.994 73907.93 1.696693 2 3499 0 229719 5273623 226220 5.193297 137831.4 0 56235.15 3600 OK 16003.59 192043 4.408702 3 993.6 0 106456 2.443893 105462.4 2.421084 63873.6 26060.4 2700 OK 7502.33 90027.96 2.066758 4 203.1 0 78459 1.601171 78255.9 1.796508 47075.4 19206.74 1800 OK 5513.456 66161.47 1.518858 5 993.6 0 93875 2.155073 92881.4 2.132264 56325 22980.58 1800 OK 6567.293 78807.52 1.809172 6 950 950 94052 2.159137 92152 2.115519 56431.2 23023.91 1800 OK 6579.393 78952.72 1.812505 7 1003.05 1250 50000 1.147842 47746.95 1.096119 20000 27199.97 360 OK 3736.665 44839.98 1.029384 8 700 0 35000 0.803489 34300 0.78742 14000 19039.98 360 OK 2624.665 31495.98 0.723048 9 1973.55 0 38135 0.875459 36161.45 0.830153 14872.65 20226.78 360 OK 2786.396 33436.76 0.767602 ROADWAY 0 0 37708 0.865657 37708 0.865657 0 0 0 NA 3142.333 37708 0.865657 SWSwale: 3255 0 74739 1.715771 71484 1.641047 0 0 0 0 TOTAL; 921278 21,14963 TOTAL; 60615.11 SQ. FT, 15.17952 Engcalc1-E-1 Bonuccelli Development Marietta & Sullivan 2-Aug-00 Stormwater Disposal Bowstring Method Calculation, Roadside Swale Capacity, Marietta Area 1: West End, Marietta, TYPICAL EA. SIDE Swale Area: 654.2942 square feet Volume: 1997.27 213.7647 1997.52 434.0295 80.97428 c0t. 1997.77 654.2942 217.0147 cu.ft. Pond Infiltration Rate: 0.001781 cfs (0.36"/hr infiltration rate) Drywell Infiltration Rate 0.3 cfs (Garrison Gravelly loam) No. of Drywells: 1 Drywell Volume: 54.45 cubic feet Total Available Storage Volulme: 271.4647 cubic feet Use Bowstring Method to check adequacy of Swale: Time increment; 2 min. Time of Concentration: 2 min. Storage req.: Outflow (c.f.s.) (up to 0. 0.00 cfs 239.792 cf. Design year flow 10 year 0.16 Acres Imp; C=0.9 Area (acres) 0.18 Developed C factor: 0.86 0.02 Acres Perv: C=0.4 Area x C 0.15 To flow generated within the West end, add the peak flow coming from the middle section below, which also must be drained by the drywell on each side of the West End of Marietta. From Area 2 outflow: 0.284605 cfs occurs after 460 minutes as shown below: No.1 No.2 No.3 No.4 No.S No.6 No.7 Time Inc. t Intensity Q dev. V in V out Storage No. 1 x 60 (in.lhr) A'C'No.3 Out " No.2 drywell infiltration rate 2 120 3.18 0.481037 58.05156 0 58.05156 4 240 3.18 0.481037 115.776 0 115.776 6 360 2.9 0.438682 158.2237 0 158.2237 8 480 2.5 0.378174 181.7806 0 181.7806 10 600 2.25 0.340356 204.4453 0 204.4453 15 900 1.76 0.266234 239.792 0 239.792 20 1200 1.45 0.219341 263.3581 90 173.3581 (overflow to drywells) 25 1500 1.22 0.184549 276.9487 103.5906 271.4647 0.045302 cfs 30 1800 1.04 0.15732 283.2835 109.9254 271.4647 0.021116 cfs 35 2100 0.92 0.139168 292.3474 118.9892 271.4647 0.030213 cfs 40 2400 0.82 0.124041 297.7828 124.4246 271.4647 0.018118 cfs 45 2700 0.75 0.113452 306.398 133.0398 271.4647 0.028717 cfs 50 3000 0.69 0.104376 313.1989 139.8408 271.4647 0.02267 cfs 55 3300 0.64 0.096813 319.5471 146.1889 271.4647 0.021161 cfs 60 3600 0.61 0.092274 332.2506 158.8925 271.4647 0.042345 cfs 65 3900 0.60 0.090762 354.0324 180.6743 271.4647 0.072606 cfs 70 4200 0.58 0.087736 368.5522 195.1941 271.4647 0.048399 cfs 75 4500 0.55 0.083198 374.4487 201.0905 271.4647 0.019655 cfs 80 4800 0.53 0.080173 384.8842 211.5261 271.4647 0.034785 cfs 85 5100 0.52 0.077904 397.3624 224.0043 271.4647 0.041594 cfs 90 5400 0.50 0.075635 408.4792 235.121 271.4647 0.037056 cfs 95 5700 0.49 0.074122 422.5462 249.1881 271.4647 0.04689 cfs 100 6000 0.49 0.073366 440.2442 266.8861 271.4647 0.058993 cfs 105 6300 0.45 0.067892 427.7687 254.4106 271.4647 -0.04159 cfs 110 6600 0.44 0.065864 434.75 261.3918 271.4647 0.023271 cfs 115 6900 0.42 0.063983 441.5274 268.1693 271.4647 0.022591 cfs 120 7200 0.41 0.062232 448.1154 274.7572 271.4647 0.02196 cfs 125 7500 0.40 0.060598 454.5268 281.1687 271.4647 0.021371 cfs 130 7800 0.39 0.059068 460.7732 287.4151 271.4647 0.020821 cfs Engcalcl-E-1+1 , Bonuccelli Development Marietta & Sullivan 2-Aug-00 Stormwater Disposal 135 8100 0.38 0.057633 466.8649 293.5068 271.4647 0.020306 cfs 140 8400 0.37 0.056283 472.8113 299.4532 271.4647 0.019821 cfs 145 8700 0.36 0.05501 478.6208 305.2627 271.4647 0.019365 cfs 150 9000 0.36 0.053807 484.3012 310.9431 271.4647 0.018935 cfs 155 9300 0.35 0.052669 489.8595 316.5013 271.4647 0.018528 cfs 160 9600 0.34 0.05159 495 3021 321.944 271.4647 0.018142 cfs 165 9900 0.33 0.050566 500.6349 327.2768 271.4647 0.017776 cfs 170 10200 0.33 0.049591 505.8635 332.5053 271.4647 0.017428 cfs 175 10500 0.32 0.048663 510.9927 337.6346 271.4647 0.017097 cfs 180 10800 0.32 0.047777 516.0273 342.6692 271.4647 0.016782 cfs 185 11100 0.31 0.046931 520.9715 347.6134 271.4647 0.016481 cfs 190 11400 0.30 0.046123 525.8294 352.4713 271.4647 0.016193 cfs 195 11700 0.30 0.045348 530.6047 357.2466 271.4647 0.015918 cfs 200 12000 0.29 0.044606 535.3008 361.9427 271.4647 0.015654 cfs 205 12300 0.29 0.043894 539.921 366.5629 271.4647 0.015401 cfs 210 12600 0.29 0.043209 544.4683 371.1102 271.4647 0.015158 cfs 215 12900 0.28 0.042552 548.9456 375.5875 271.4647 0.014924 cfs 220 13200 0.28 0.041919 553.3555 379.9974 271.4647 0.0147 cfs 225 13500 0.27 0.041309 557.7006 384.3425 271.4647 0.014484 cfs 230 13800 0.27 0.040721 561.9832 388.625 271.4647 0.014275 cfs 235 14100 0.27 0.040154 566.2055 392.8473 271.4647 0.014074 cfs 240 14400 0.26 0.039607 570.3696 397.0115 271.4647 0.013881 cfs 245 14700 0.26 0.039078 574.4776 401.1195 271.4647 0.013693 cfs 250 15000 0.25 0.038567 578.5313 405.1732 271.4647 0.013512 cfs 255 15300 0.25 0.038072 582.5325 409.1744 271.4647 0.013337 cfs 260 15600 0.25 0.037593 586.4829 413.1247 271.4647 0.013168 cfs 265 15900 0.25 0.037129 590.384 417.0259 271.4647 0.013004 cfs 270 16200 0.24 0.03668 594.2375 420.8794 271.4647 0.012845 cfs 275 16500 0.24 0.036244 598.0447 424.6866 271.4647 0.012691 cfs 280 16800 0.24 0.03582 601.8071 428.449 271.4647 0.012541 cfs 285 17100 0.23 0.035409 605.5259 432.1678 271.4647 0.012396 cfs 290 17400 0.23 0.03501 609.2025 435.8444 271.4647 0.012255 cfs 295 17700 0.23 0.034622 612.8379 439.4798 271.4647 0.012118 cfs 300 18000 0.23 0.034245 616.4335 443.0753 271.4647 0.011985 cfs 305 18300 0.22 0.033878 619.9901 446.632 271.4647 0.011856 cfs 310 18600 0.22 0.033521 623.509 450.1508 271.4647 0.011729 cfs 315 18900 0.22 0.033173 626.991 453.6329 271.4647 0.011607 cfs 320 19200 0.22 0.032834 630.4372 457.0791 271.4647 0.011487 cfs 325 19500 0.21 0.032504 633.8485 460.4903 271.4647 0.011371 cfs 330 19800 0.21 0.032182 637.2257 463.8676 271.4647 0.011257 cfs 335 20100 0.21 0.031868 640.5698 467.2116 271.4647 0.011147 cfs 340 20400 0.21 0.031562 643.8814 470.5233 271.4647 0.011039 cfs 345 20700 0.21 0.031263 647.1615 473.8034 271.4647 0.010934 cfs 350 21000 0.20 0.030971 650.4107 477.0526 271.4647 0.010831 cfs 355 21300 0.20 0.030686 653.6298 480.2717 271.4647 0.01073 cfs 360 21600 0.20 0.030407 656.8195 483.4614 271.4647 0.010632 cfs 365 21900 0.20 0.030135 659.9805 486.6223 271.4647 0.010536 cfs 370 22200 0.20 0.029869 663.1133 489.7552 271.4647 0.010443 cfs 375 22500 0.20 0.029609 666.2187 492.8606 271.4647 0.010351 cfs 380 22800 0.19 0.029354 669.2972 495.939 271.4647 0.010262 cfs 385 23100 0.19 0.029105 672.3494 498.9912 271.4647 0.010174 cfs 390 23400 0.19 0.028861 675.3759 502.0177 271.4647 0.010088 cfs 395 23700 0.19 0.028623 678.3771 505.019 271.4647 0.010004 cfs 400 24000 0.19 0.028389 681.3538 507.9956 271.4647 0.009922 cfs 405 24300 0.19 0.02816 684.3062 510.9481 271.4647 0.009842 cfs 410 24600 0.18 0.027936 687.235 513.8769 271.4647 0.009763 cfs Engcalcl-E-1 +2 Bonuccelli Development Marietta & Sullivan 2-Aug-00 Stormwater Disposal 415 24900 0.18 0.027716 690.1406 516.7825 271.4647 0.009685 cfs 420 25200 0.18 0.0275 693.0235 519.6654 271.4647 0.00961 cfs 425 25500 0.18 0.027289 695.8841 522.5259 271.4647 0.009535 cfs 430 25800 0.18 0.027082 698.7228 525.3647 271.4647 0.009462 cfs 435 26100 0.18 0.026878 701.5401 528.182 271.4647 0.009391 cfs 440 26400 0.18 0.026679 704.3364 530.9782 271.4647 0.009321 cfs 445 26700 0.18 0.026483 707.112 533.7539 271.4647 0.009252 cfs 450 27000 0.17 0.026291 709.8674 536.5092 271.4647 0.009185 cfs 455 27300 0.17 0.026102 712.6029 539.2447 271.4647 0.009118 cfs 460 27600 0.17 0.025917 715.3188 541.9607 271.4647 0.009053 cfs 465 27900 0.17 0.025735 718.0156 544.6575 271.4647 0.008989 cfs 470 28200 0.17 0.025556 720.6936 547.3354 271.4647 0.008927 cfs 475 28500 0.17 0.02538 723.353 549.9949 271.4647 0.008865 cfs 480 28800 0.17 0.025208 725.9943 552.6361 271.4647 0.008804 cfs 485 29100 0.17 0.025038 728.6177 555.2595 271.4647 0.008745 cfs . 490 29400 0.16 0.024871 731.2235 557.8653 271.4647 0.008686 cfs 495 29700 0.16 0.024707 733.812 560.4539 271.4647 0.008628 cfs 500 30000 0.16 0.024546 736.3836 563.0254 271.4647 0.008572 cfs 505 30300 0.16 0.024387 738.9384 565.5803 271.4647 0.008516 cfs 510 30600 0.16 0.024231 741.4768 568.1187 271.4647 0.008461 cfs 515 30900 0.16 0.024077 743.999 570.6409 271.4647 0.008407 cfs 520 31200 0.16 0.023926 746.5054 573.1472 271.4647 0.008354 cfs 525 31500 0.16 0.023777 748.996 575.6379 271.4647 0.008302 cfs 530 31800 0.16 0.023631 751.4713 578.1131 271.4647 0.008251 cfs 535 32100 0.16 0.023486 753.9313 580.5732 271.4647 0.0082 cfs 540 32400 0.15 0.023344 756.3765 583.0183 271.4647 0.00815 cfs 545 32700 0.15 0.023205 758.8069 585.4487 271.4647 0.008101 cfs 550 33000 0.15 0.023067 761.2228 587.8646 271.4647 0.008053 cfs 555 33300 0.15 0.022931 763.6244 590.2663 271.4647 0.008005 cfs 560 33600 0.15 0.022798 766.012 592.6539 271.4647 0.007959 cfs 565 33900 0.15 0.022666 768.3857 595.0276 271.4647 0.007912 cfs 570 34200 0.15 0.022536 770.7458 597.3877 271.4647 0.007867 cfs 575 34500 0.15 0.022408 773.0924 599.7343 271.4647 0.007822 cfs 580 34800 0.15 0.022282 775.4258 602.0676 271.4647 0.007778 cfs 585 35100 0.15 0.022158 777.7461 604.3879 271.4647 0.007734 cfs 590 35400 0.15 0.022035 780.0534 606.6953 271.4647 0.007691 cfs 595 35700 0.14 0.021914 782.3481 608.99 271.4647 0.007649 cfs 600 36000 0.14 0.021795 784.6303 611.2721 271.4647 0.007607 cfs 605 36300 0.14 0.021677 786.9 613.5419 271.4647 0.007566 cfs 610 36600 0.14 0.021561 789.1576 615.7995 271.4647 0.007525 cfs 615 36900 0.14 0.021447 791.4031 618.045 271.4647 0.007485 cfs 620 37200 0.14 0.021334 793.6368 620.2787 271.4647 0.007446 cfs 625 37500 0.14 0.021223 881.2403 707.8821 271.4647 0.292012 cfs 630 37800 0.14 0.021113 968.8322 795.474 271.4647 0.291973 cfs 635 38100 0.14 0.021004 1056.413 883.0545 271.4647 0.291935 cfs 640 38400 0.14 0.020897 1143.982 970.6238 271.4647 0.291897 cfs Note the decline in the infiltration rate into the drywells in the far right column; this indicates that the peak infiltration rate (and worst case storage) is reached at 625 minutes when the middle section begins to drain into the west section swale, in the event of frozen ground. Area 2: Middle Section, Marietta TYPICAL EA. SIDE- overflows into and is part of Area 1: square fee cu.ft. Swale Area: 1090 Volume: 2006.58 30 2006.83 560 73.75 cu.ft. Engcalcl-E-1+3 Bonucceili Development Marietta & Sullivan 2-Aug-00 Stormwater Disposal 2007.58 1090 692.5 cu.ft. Once pond volume is exceeded, then outfiow over end berm: Pond Infiltration Rate: 0.00025 cfs (0.36"/hr infiltration rate) Drywell Infiltration Rate 0.3 cfs (Garrison Gravelly loam) End Berm,"C" 3 (Broadcrested Weir) End Berm weir equation: 3'L"H^3/2 L= 3 feet; H=.1 feet Therefore Weir outflow: 0.284605 cfs (capacity) No. of Drywells: 0 Drywell Volume: 0 cubic feet Total Available Storage Volulme: 692.5 cubic feet Use Bowstring Method to check adequacy of Swale: Time increment; 2 min. Time of Concentration: 2 min. Storage req.: Outflow (c.f.s.) 0.00 cfs 693.763 cf. Design year flow 10 year 0.107 Acres Imp; C=0.9 Area (acres) 0.132 Developed C factor: 0.805118 0.025 Acres Perv: C=0.4 Area x C 0.106 No.1 No.2 No.3 No.4 No.S No.6 No.7 Time Inc. t Intensity Q dev. V in V out Storage No. 1 x 60 (in./hr) A"C"No.3 Out 4 No.2 2 120 3.18 0.419328 50.60448 0 50.60448 4 240 3.18 0.419328 100.9238 0 100.9238 6 360 2.9 0.382406 137.9262 0 137.9262 8 480 2.5 0.32966 158.4611 0 158.4611 10 600 2.25 0.296694 178.2183 0 178.2183 15 900 1.76 0.232081 209.0305 0 209.0305 20 1200 1.45 0.191203 229.5735 0 229.5735 25 1500 1.22 0.160874 241.4207 0 241.4207 30 1800 1.04 0.137139 246.9428 0 246.9428 35 2100 0.92 0.121315 254.8439 0 254.8439 40 2400 0.82 0.108129 259.5821 0 259.5821 45 2700 0.75 0.098898 267.092 0 267.092 50 3000 0.69 0.090986 273.0205 0 273.0205 55 3300 0.64 0.084393 278.5544 0 278.5544 60 3600 0.61 0.080437 289.6283 0 289.6283 65 3900 0.60 0.079118 308.6158 0 308.6158 70 4200 0.58 0.076481 321.2729 0 321.2729 75 4500 0.55 0.072525 326.413 0 326.413 80 4800 0.53 0.069888 335.5098 0 335.5098 85 5100 0.52 0.06791 346.3872 0 346.3872 90 5400 0.50 0.065932 356.0779 0 356.0779 95 5700 0.49 0.064613 368 3404 0 368.3404 100 6000 0.49 0.063954 383.768 0 383.768 105 6300 0.45 0059183 372.8929 0 372.8929 110 6600 0.44 0.057415 378.9786 0 378.9786 115 6900 0.42 0.055775 384.8866 0 384.8866 120 7200 0.41 0.054249 390.6294 0 390.6294 125 7500 0.40 0.052824 396.2184 0 396.2184 130 7800 0.39 0.051491 401.6634 0 401.6634 135 8100 0.38 0.050239 406.9737 0 406.9737 140 8400 0.37 0.049062 412.1572 0 412.1572 145 8700 0.36 0.047953 417.2215 0 417.2215 Engcalc1-E-1+4 Bonuccelli Development Marietta & Suliivan 2-Aug-00 Stormwater Disposal 150 9000 0.36 0.046905 422.1732 0 422.1732 155 9300 0.35 0.045913 427.0184 0 427.0184 160 9600 0.34 0.044972 431.7628 0 431.7628 165 9900 0.33 0.044079 436.4116 0 436.4116 170 10200 0.33 0.043229 440.9694 0 440.9694 175 10500 0.32 0.04242 4454406 0 445.4406 180 10800 0.32 0.041648 449.8293 0 449.8293 185 11100 0.31 0.040911 454.1393 0 454.1393 190 11400 0.30 0.040206 458.374 0 458.374 195 11700 0.30 0.039531 462.5367 0 462.5367 200 12000 0.29 0.038884 466.6304 0 466.6304 205 12300 0.29 0.038263 470.6579 0 470.6579 210 12600 0.29 0.037666 474.6218 0 474.6218 215 12900 0.28 0.037093 478.5248 0 478.5248 220 13200 0.28 0.036541 482.369 0 482.369 225 13500 0.27 0.03601 486.1566 0 486.1566 230 13800 0.27 0.035498 489.8898 0 489.8898 235 14100 0.27 0.035003 493.5705 0 493.5705 240 14400 0.26 0.034526 497.2004 0 497.2004 245 14700 0.26 0.034065 500.7814 0 500.7814 250 15000 0.25 0.033619 504.3151 0 504.3151 255 15300 0.25 0.033188 507.803 0 507.803 260 15600 0.25 0.032771 511.2466 0 511.2466 265 15900 0.25 0.032366 514.6473 0 514.6473 270 16200 0.24 0.031974 518.0064 0 518.0064 275 16500 0.24 0.031594 521.3253 0 521.3253 280 16800 0.24 0.031225 524.605 0 524.605 285 17100 0.23 0.030867 527.8467 0 527.8467 290 17400 0.23 0.030519 531.0516 0 531.0516 295 17700 0.23 0.030181 534.2207 0 534.2207 300 18000 0.23 0.029852 537.355 0 537.355 305 18300 0.22 0.029532 540.4554 0 540.4554 310 18600 0.22 0.029221 543.5228 0 543.5228 315 18900 0.22 0.028917 546.5582 0 546.5582 320 19200 0.22 0.028622 549.5623 0 549.5623 325 19500 0.21 0.028334 552.536 0 552.536 330 19800 0.21 0.028054 555.4799 0 555.4799 335 20100 0.21 0.02778 558.395 0 558.395 340 20400 0.21 0.027513 561.2818 0 561.2818 345 20700 0.21 0.027252 564.1411 0 564.1411 350 21000 0.20 0.026998 566.9735 0 566.9735 355 21300 0.20 0.026749 569.7797 0 569.7797 360 21600 0.20 0.026507 572.5602 0 572.5602 365 21900 0.20 0.026269 575.3156 0 575.3156 370 22200 0.20 0.026037 578.0466 0 578.0466 375 22500 0.20 0.02581 580.7536 0 580.7536 380 22800 0.19 0.025589 583.4372 0 583.4372 385 23100 0.19 0.025371 586.0978 0 586.0978 390 23400 0.19 0.025159 588.736 0 588.736 395 23700 0.19 0.024951 591.3523 0 591.3523 400 24000 0.19 0.024747 593.9471 0 593.9471 405 24300 0.19 0.024547 596.5208 0 596.5208 410 24600 0.18 0.024352 599 0739 0 599.0739 415 24900 0.18 0.02416 601.6067 0 601.6067 420 25200 0.18 0.023972 604.1198 0 604.1198 425 25500 0.18 0.023788 606.6134 0 606.6134 Engcalc1-E-1+5 Bonuccelli Development Manetta & Sullivan 2-Aug-00 Stormwater Disposal 430 25800 0.18 0.023607 609.088 0 609.088 435 26100 0.18 0.02343 611.5438 0 611.5438 440 26400 0.18 0.023256 613.9814 0 613.9814 445 26700 0.18 0.023086 616.401 0 616.401 450 27000 0.17 0.022918 618.8029 0 618.8029 455 27300 0.17 0.022754 621.1874 0 621.1874 460 27600 0.17 0.022592 623.555 0 623.555 465 27900 0.17 0.022433 625.9058 0 625.9058 470 28200 0.17 0.022277 628.2402 0 628.2402 475 28500 0.17 0.022124 630.5585 0 630.5585 480 28800 0.17 0.021974 632.8609 0 632.8609 485 29100 0.17 0.021826 635.1478 0 635.1478 490 29400 0.16 0.02168 637.4193 0 637.4193 495 29700 0.16 0.021537 639.6758 0 639.6758 . 500 30000 0.16 0.021397 641.9174 0 641.9174 505 30300 0.16 0.021258 644.1445 0 644.1445 510 30600 0.16 0.021122 646.3573 0 646.3573 515 30900 0.16 0.020988 648.556 0 648.556 520 31200 0.16 0.020857 650.7408 0 650.7408 525 31500 0.16 0.020727 652.9119 0 652.9119 530 31800 0.16 0.020599 655.0696 0 655.0696 535 32100 0.16 0.020474 657.2141 0 657.2141 540 32400 0.15 0.02035 659.3456 0 659.3456 545 32700 0.15 0.020228 661.4642 0 661.4642 550 33000 0.15 0.020108 663.5702 0 663.5702 555 33300 0.15 0.019989 665.6638 0 665.6638 560 33600 0.15 0.019873 667.745 0 667.745 565 33900 0.15 0.019758 669.8143 0 669.8143 570 34200 0.15 0.019645 671.8716 0 671.8716 575 34500 0.15 0.019533 673.9172 0 673.9172 580 34800 0.15 0.019424 675.9512 0 675.9512 585 35100 0.15 0.019315 677.9738 0 677.9738 590 35400 0.15 0.019208 679.9852 0 679.9852 595 35700 0.14 0.019103 681.9855 0 681.9855 600 36000 0.14 0.018999 683.9749 0 683.9749 605 36300 0.14 0.018896 685.9535 0 685.9535 610 36600 0.14 0.018795 687.9214 0 687.9214 615 36900 0.14 0.018696 689.8789 0 689.8789 620 37200 0.14 0.018597 691.826 0 691.826 625 37500 0.14 0.0185 693.763 0 693.763 Begin Weir Overflow 630 37800 0.14 0.018404 695.6898 85.3815 610.3083 to Area 1 Area 3: East End, Marietta TYPICAL EA. SIDE Swale Area: 2000 square feet Volume: 1997.27 18 1997.52 1009 128.375 cu.ft. 1997.77 2000 504.5 cu.ft. Pond Infiltration Rate: 0.00015 cfs (0.36"/hr infiltration rate) Drywell Infiltration Rate 0.3 cfs (Garrison Gravelly loam) No. of Drywells: 1 Drywell Volume: 54.45 cubic feet Total Available Storage Volulme: 558.95 cubic feet Use Bowstring Method to check adequacy of Swale. Time increment; 2 min. Engcalcl-E-1+6 Bonuccelli Development Marietta & Sullivan 2-Aug-00 Stormwater Disposal Time of Concentration: 2 min. Storage req.: Outflow (c.f.s.) (up to 0. 0.00 cfs 558.95 cf. Design year flow 10 year 0.098 Acres Imp; C=0.9 Area (acres) 0.143 Developed C factor: 0.74 0.046 Acres Perv: C=0.4 Area x C 0.106 No.1 No.2 No.3 No.4 No.5 No.6 No.7 Time Inc. t Intensity Q dev. V in V out Storage No. 1 x 60 (in./hr) A`C'No.3 Out ' No.2 2 120 3.18 0.456267 55.06233 0 55.06233 0 4 240 3.18 0.481037 115.776 0 115.776 0 6 360 2.9 0.438682 158.2237 0 158.2237 0 8 480 2.5 0.378174 181.7806 0 181.7806 0 10 600 2.25 0.340356 204.4453 0 204.4453 0 15 900 1.76 0.266234 239.792 0 239.792 0 20 1200 1.45 0.219341 263.3581 0 263.3581 0 25 1500 1.22 0.184549 276.9487 0 276.9487 0 30 1800 1.04 0.15732 283.2835 0 283.2835 0 35 2100 0.92 0.139168 292.3474 0 292.3474 0 40 2400 0.82 0.124041 297.7828 0 297.7828 0 45 2700 0.75 0.113452 306.398 0 306.398 0 50 3000 0.69 0.104376 313.1989 0 313.1989 0 55 3300 0.64 0.096813 319.5471 0 319.5471 0 60 3600 0.61 0.092274 332.2506 0 332.2506 0 65 3900 0.60 0.090762 354.0324 0 354.0324 0 70 4200 0.58 0.087736 368.5522 0 368.5522 0 75 4500 0.55 0.083198 374.4487 0 374.4487 0 80 4800 0.53 0.080173 384.8842 0 384.8842 0 85 5100 0.52 0.077904 397.3624 0 397.3624 0 90 5400 0.50 0.075635 408.4792 0 408.4792 0 95 5700 0.49 0.074122 422.5462 0 422.5462 0 100 6000 0.49 0.073366 440.2442 0 440.2442 0 105 6300 0.45 0.067892 427.7687 0 427.7687 0 110 6600 0.44 0.065864 434.75 0 434.75 0 115 6900 0.42 0.063983 441.5274 0 441.5274 0 120 7200 0.41 0.062232 448.1154 0 448.1154 0 125 7500 0.40 0.060598 454.5268 0 454.5268 0 130 7800 0.39 0.059068 460.7732 0 460.7732 0 135 8100 0.38 0.057633 466.8649 0 466.8649 0 140 8400 0.37 0.056283 472.8113 0 472.8113 0 145 8700 0.36 0.05501 478.6208 0 478.6208 0 150 9000 0.36 0.053807 484.3012 0 484.3012 0 155 9300 0.35 0.052669 489.8595 0 489.8595 0 160 9600 0.34 0.05159 495.3021 0 495.3021 0 165 9900 0.33 0.050566 500.6349 0 500.6349 0 170 10200 0.33 0.049591 505.8635 0 505.8635 0 175 10500 0.32 0.048663 510.9927 90 420.9927 0.3 180 10800 0.32 0.047777 516.0273 95.03459 558.95 0.016782 185 11100 0.31 0.046931 520.9715 99.97883 558.95 0.016481 Note the decline in the infiltration rate into the drywells in the far right column; this indicates that the peak infiltration rate (and worst case storage) is reached at 175 minutes when the overfiow from the swale begins to enter the drywell grate, in the event of frozen ground. Worst Case Inlet Depression, Type 1 Inlet: 0.1 ft. Engcalcl-E-1+7 Bonuccelli Development Marietta & Sullivan 2-Aug-00 Stormwater Oisposal Flow: 0.476934 cfs = Qmax (use TR55 flow calc where applicable) maximum allowable ponding: 0.2 feet = h = head for weir of inlet opening Required area of inlets: Cw= 3 Q=Cw*Lh^(3/2) L=Q/(Cw'h^(3/2)) Lmin.= 1.777428 feet Therefore a 4' long inlet will be more than adequate for a 10-year storm event for each curb inlet. Worst Case Drywell Inlet flow: Flow: 0.48 cfs = Qmax (use TR55 flow calc where applicable) maximum allowable ponding: 0.4 feet = h = head for weir of drywell opening Required area of drywell grate: Cw= 3 Q=Cw'Lh^(3/2) , L=Q/(Cw'h^(3!2)) Lmin.= 0.628416 feet Therefore a standard type 4 grate with an effective weir length of 5.694137 feet Is adequate for much more than a 10-year storm event for each drywell. Engcalc1-E-1+8 Bonuccelli Development Industrial Development at Sullivan and Marietta 2-Aug-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Sile Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Use conservative 5 min intensity i= 3.2 in/hr Disposal Capacity: Garrison Gravelly LoamNery Stony Loam Soil Estimated Turf Infiltration Capacity q= 0.36 in/hr Ratio of i/q 8.888889 Maximum Storage Depth: 6 in 10 year, one hour intensity: 3.2 in/hr 10 year, 24 hour total: 2.12 in. Parcel 1 Drain Basin Total Improved Impervious Surface Area: 73907.93 square feet Asphalt Impervious Surface Area: new: 39281 square feet Roof: direct, 32422.65 square feet Sidewalk: new. 2204.738 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 9227.066 square feet Depressed Infiltration Area: 6158.994 square feet cultivated surFace Additional available infiltration volume on side slopes: Perimeler 6" above boltom 470.8756 square feet additional on slopes Total Available for Infiltration: 6629.87 square fee = 3197.216 ft3 Total Required Under County Standard: 1636.689 113 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year intensity: 3.2 in/hour Time of concentration: 3.65 min. Area Impervious: 73907.93 square feet Area Pervious: 9227.066 square feet Peak Q: 5.06 cfs Peak Infiltration Rate: 0.36 inJhour Pervious Surface, non-swale: 2597 196 square feet Peak Q, perv, non-swale: 0.05 cfs Infiltration capacity, perv, non swale: 0.02 cfs Engcalcl-G-1 Bonuccelli Development Industrial Development at Sullivan and Marietta 2-Aug-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. , Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Peak Q, remainder: 5 03 cfs ' Swale Infiltration Capacity. 0.0552 cfs drywell infiltration cap.: 0.3 cfs each (1 total) Storage Required, 5 minute Storm: 1403.71 cubic (eet Storage Available, Swale Only: 3197.216 cubic feet Plus Drywells: 54.45 cubic feet Total: 3251.67 cubic feet OK Peak Runoff, 50-year storm: (5 minute) 50-year intensity: 5.1 iNhour Peak Q: 8.06 cfs Storage Required: 2394.30 cubic feet • Swale Plus Drywell: 3251.67 cubic feet OK Parcel 2 Drain Basin Total Improved Impenrious Surface Area: 192043 square feet Asphalt Impervious Surface Area: new. 51400 square feet Roof: direct. 137831.4 square feet Sidewalk: new: 2811.758 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane Counly Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 37675.96 square feet Depressed Infiltration Area. 16003.59 square feet cultivated surface Additional available infiltration volume on side slopes: Perimeter 6" above bottom 759.0317 square feet additional on slopes Total Available for Infiltration. 16762.62 square fee = 8191.551 ft3 Total Required Under County Standard: 2141.662 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year mtensity: 1.95 inlhour Time of concentration: 13 min. Area Impervious: 192043 square feet Area Pervious- 37675.96 square feet Peak Q: 8.16 cfs Peak Infiltration Rate: 0.36 inlhour Pervious Surface, non-swale: 20913.34 square feet Engcalc1-G-2 Bonuccelli Development Industnal Development at Sullivan and Marietta 2-Aug-00 7echCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Peak Q, perv, non-swale: 0.23 cfs Infiltration capacity, perv, non swale: 0.17 cfs Peak Q, remainder: 7.98 cfs Swale Infiltration Capacity: 0.1397 cfs drywell infiltration cap.: 0.3 cfs each (1 total) Storage Required, 13 minute Storm: 5885.06 cubic feet Storage Available, Swale Only: 8191.551 cubic feet Plus Drywells: 54.45 cubic feet Total: 8246.006 cubic feet OK Peak Runoff, 50-year storm: (13 minute) 50-year intensity: 2.7 in/hour Peak Q: 11.30 cfs Storage Required: . 8751.66 cubic feet Swale Plus Drywell: 8246.006 cubic feet NG Storage Available, 12": 16762.62 cubic feet OK Parcel 3 Drain Basin Total Improved Impervious Surface Area: 90027.96 square feet Asphalt Impervious Surface Area: new: 24851 square feet Roof: direct: 63873.6 square feet Sidewalk: new: 1303.02 square feet Utdize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 16428 04 square feet Depressed Infiltration Area: 7502.33 square feet cultivated surface Additional available infiltration volume on side slopes: Perimeter 6" above bottom 519.696 square feet additional on slopes Total Available for Infiltration: 8022.026 square fee = 3881.089 ft3 Total Required Under County Standard: 1035.473 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year intensity: 3.2 inlhour . Time of concentration: 4.6 min. Area Impervious: 90027.96 square feet Area Pervious. 16428.04 square feet Engcalc1-G-3 Bonuccelli Development Industrial Development at Sullivan and Marietta 2-Aug-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Nydrology Study Design to 10 year storm (for review by Spokane County Engineers). Peak Q: 6.25 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale: 8406 011 square feet Peak Q, perv, non-swale: 0.15 cfs Infiltration capacity, perv, non swale: 0.07 cfs Peak Q, remainder: 6.18 cfs Swale Infiltration Capacity: 0.0669 cfs drywell infiltration cap.:' 0.3 cfs each (1 total) Storage Required, 5 minute Storm: 1745.12 cubic feet Storage Available, Swale Only: 3881.089 cubic feet Plus Drywells- 54.45 cubic feet Total: 3935.543 cubic feet OK Peak Runoff, 50-year storm: (5 minute) 50-year intensity: 5.1 in/hour Peak Q. 9.97 cfs Storage Required: 2967.11 cubic feet Swale Plus Drywell: 3935.543 cubic feet OK Parcel 4 Drain Basin Total Improved Impervious Surface Area: 66161.47 square feet Asphalt Impervious SurFace Area: new: 18126 square feet Roof: direct: 47075.4 square feet Sidewalk: new: 960.3372 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 12297.53 square feet Depressed Infiltration Area: 5513.456 square feet cultivated surface Additional available infiltration volume on side slopes: Perimeter 6" above bottom 445.5159 square feet additional on slopes Total Available for Infiltration: 5958.972 square fee = 2868.107 ft3 Total Required Under County Standard: 755.2388 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 09 Pervious Surface C: 0.25 Engcalcl-G-4 u ~ Bonuccelli Development Industnal Development at Sullivan and Marietta 2-Aug-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). 10-year intensity: 2.5 in/hour Time o( concentration: 8 min. Area Impervious• 66161.47 square feet Area Pervious: 12297.53 square feet Peak Q: 3.59 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale: 6338.559 square feet Peak Q, perv, non-swale: 0.09 cfs Infiltralion capacity, perv, non swale: 0.05 cfs Peak Q, remainder: 3.54 cfs Swale Infiltration Capacity. 0.0497 cfs drywell infiltration cap.: 0.3 cfs each (1 total) Storage Required, 8 minute Storm: 1531.87 cubic feet Storage Available, Swale Only. 2868.107 cubic feet Plus Drywells: 54.45 cubic feet Total: 2922.561 cubic feet OK Peak Runoff, 50-year storm: (8 minute) 50-year intensity: 3.65 in/hour Peak Q. 5.25 cfs Storage Required: 2481.68 cubic feet Swale Plus Drywell: 2922.561 cubic feet OK Parcel 5 Drain Basin Total Improved Impervious Surface Area: 78807.52 square feet Asphalt Impervious Surface Area: new: 21333 square feet Roof: direct: 56325 square feet Sidewalk: new• 1149.029 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 15067.48 square feet Depressed Infiltration Area: 6567.293 square feet cultivated surface Additional available infiltration volume on side slopes: Perimeter 6" above bottom 486.233 square feet additional on slopes Total Available for Infiltration: 7053.526 square fee = 3405.205 ft3 Total Required Under County Standard: 888.8954 ft3 OK Hydrology Check: Engcalc1-G-5 , . Bonuccelli Development Industrial Development at Sullivan and Marietta 2-Aug-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year intensity: 2.6 in/hour Time of concentration: 7.5 min. Area Impervious- 78807.52 square feet Area Pervious: 15067.48 square feet Peak Q: 4.46 cfs Peak Infiltration Rate- 0.36 inlhour • Pervious Surface, non-swale: 8013.954 square feet Peak Q, perv, non-swale: 0.12 cfs Infiltration capacity, perv, non swale: 0.07 cfs Peak Q, remainder: 4.39 cfs Swale Infiltration Capacity: 0.0588 cfs drywell infiltration cap.: 0.3 cfs each (1 total) Storage Required, 7.5 minute Storm: 1814 73 cubic feet Storage Available, Swale Only: 3405.205 cubic feet Plus Drywells: 54.45 cubic feet Total: 3459.659 cubic feet OK Peak Runoff, 50-year storm: (7.5 minute) 50-year intensity: 3.8 in/hour Peak Q: 6.52 cfs Storage Required: 2897.59 cubic feet Swale Plus Drywell: 3459.659 cubic feet OK Parcel 6 Drain Basin Total Improved Impervious Surface Area: _ 78952.72 square feet Asphalt Impervious Surface Area: new: 21370 square feet Roof: direct: 56431.2 square feet Sidewalk. new. 1151.195 square feet Utilize biofillration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Available Grassy Area: 15099.28 square feet Depressed Infiltration Area- . 6579.393 square feet cultivated surface Additional available infiltration volume on side slopes- Perimeter 6" above bottom 486.6807 square feet additional on slopes Total Available for Infiltration: Engcalcl-G-6 . , Bonucceih D2velopment Industrial Deveiopment 2t SulEivan and Marietta 2-Aug-Q0 TechCofi, Inc. Prepared by Alan E. Gay, P-r-- Sike HydroEogy Skudy Design to 10 year storm (for review by Spakane County Engineers). 7066_074 square fee = 3411.367 ft3 Total Required Under Couniy Standard: 890.43 i#3 OK Hydrology Gheck: Rational Nlethod: Peak Runoff, 1 b-year storm, q=CIA Irnpervious SurFace C: 0_9 Pervious SurFace C. 0_25 14-year intensity: 2.6 inlhour Time of caneentrakion: 7.5 min. Area Impervious; 78952.72 square feet Area Pervious- 15099.28 square feet - Peak Q: 4 47 cf5 Peak ~nfiltratian Rate: 0_36 inlhour Perviaus SurFace, non-swale: 8033.21 square feet Peak 0, Perv, nora-swale- 4,12 cis Infiftration capaciky, perv, non swale. 0 07 cfs Peak 0, recnainder' 4.40 cfs Swale Infiltraxion Gapaciky' 0.0589 cfs dryweJl infltratian cap_- 0_3 cfs each {1 4otal) 5torage Required, 7.5 minute Storrn: 1818,34 cu bic feet S#orage Available, Swale Only: 3411.367 cubic feet Plus Drywe[!s- 54_45 cubic feet Total. 3465.821 cuhic feet OK Peak Runoff, 50-year stcsrm; {7,5 rninute} 50-year ~ntensity: 3,8 iNhour Peak 0_ 6.53 cfs Storage Requircd: 2903 03 cubic feet Swale Plus Drywell' 3465.821 cubic feet QK Parcel 7 Drain Basin Totaf Irnproved Impervious Surface Area: 44839,98 square feet Asphalk Impervious Surface Area: new; 23480 square feek Roof: direct: 20000 square feet Sidewalk. new: 1359.999 5quare feet Ukihze biofiltrakion svrrale (grassy) fqr disposaf_ Assume antecedant saturated soil condilion5' Utifize Spokane County Type A drywelfs for overflaw. Include stflrage vaiume of drywell$ as well aa d"ell infiltratipn capacity. Availabfe Grassy Area- 5160 024 square feet Depressed Infiltration Area. 3136,665 square feet cultivated surface Engcalcl-G-7 Bonuccelli Development Industrial Development at Sullivan and Marietta 2-Aug-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). Additional available infiltration volume on side slopes: Perimeter 6" above bottom 366.7696 square feet additional on slopes Total Available for Infiltration: 4103.434 square fee = 1960.025 ft3 Tolal Required Under County Standard: 978.3324 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 09 Pervious Surface C: 0.25 10-year intensity: 3.2 inlhour Time of concentration: 3 min. Area Impervious: 44839.98 square feet Area Pervious: 5160.024 square feet Peak Q: 3.06 cfs Peak Infiltration Rate: 0.36 inlhour Pervious Surface, non-swale: 1056.59 square feet Peak Q, perv, non-swale: 0.02 cfs Infiltration capacity, perv, non swale: 4.01 cfs Peak Q, remainder: 3.05 cfs Swale Infiltration Capacity: 0.0342 cfs drywell infiltration cap.: 0.3 cfs each (1 total) Storage Required, 5 minute Storm• 814.92 cubic feet Storage Available, Swale Only: 1960.025 cubic feet Plus Drywells: 54.45 cubic feet Total: 2014.479 cubic feet OK Peak Runoff, 50-year storm: (5 minute) 50-year intensity: 5.1 inlhour Peak Q: 4.88 cfs Storage Required: 1439.70 cubic feet Swale Plus Drywell: 2014.479 cubic feet OK Parcel 8 Drain Basin Total Improved Impervious Surface Area: 31495.98 square feet Asphalt Impervious Surface Area: new: 16544 square feet Roof: direct: 14000 square feet Sidewalk: new: 951.999 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: Utilize Spokane County Type A drywells for overflow. Include storage volume of drywells as well as drywell infiltration capacity. Engcalcl-G-8 . , Bonuccelli Development Industrial Development al Sullivan and Marietta 2-Aug-00 TechCon, Inc. Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). , Available Grassy Area: _ 3504.017 square feet Depressed Infiltration Area• 2624.665 square feet cultivated surface Additional available infiltration volume on side slopes: Perimeter 6" above bottom 307.3889 square feet additional on slopes Total Available for Infiltration: 2932.054 square fee = 1389.18 ft3 Total Required Under County Standard: 689.3327 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year intensity: 3.2 in/hour Time of concentration: 5 min. Area Impervious- 31495.98 square feet Area Pervious: 3504 017 square feet Peak Q: 2.15 cfs Peak Infiltration Rate: 0.36 in/hour Pervious Surface, non-swale. 571.963 square feet Peak Q, perv, non-swale: 0.01 cfs Infiltralion capacity, perv, non swale: 0.00 cfs Peak Q, remainder: 2.14 cfs Swale Infiltration Capacity: 0.0244 cfs drywell infiltration cap.: 0.3 cfs each (1 total) Storage Required, 5 minute Storm: 545.26 cubic feet Storage Available, Swale Only: 1389.18 cubic feet Plus Drywells: 54.45 cubic feet Total: 1443.634 cubic feet OK Peak Runoff, 50-year storm- (5 minute) 50-year intensity: 5.1 inlhour Peak Q: 3.42 cfs Storage Required: 1003.34 cubic feel Swale Plus Drywell: 1443.634 cubic feet OK Parcel 9 Drain Basin Total Improved Impervious Surface Area: 33436 76 square feet Asphalt Impervious Surface Area: new: 17553 square feet Roof: direct: 14872.65 square feet Sidewalk: Engcalc1-G-9 f ~ a Bonuccel'lf C}evelopment Industrial ❑evelopment at Sullivan and Marieika 2-Aug-O0 TechCon, Inc. Prepared by Alan E. Gay. P E Site Hydrology 5#udy aesign ko 10 year skortn (for rewiew by 5pokane County Engineers). new~ 1011 339 square #eet Utilize biofiitration swale (grassy) for disposal. Aasume antecedanf saturated soil conditions: lJtilize Spokane County 7ype A drywells for overflaw. Ertclude sforage volume af drywells as well as drywell infiltratian capacity. Available Grassy Area; 469$.245 square feef Qepre$5ed InFiltra#iran llrea• 27$6.396 square feet cultfvaked surface Addjkior,al available infiltratrvn vQfume orr sade slopes: Perimeter 6" above bottom 316.718 squ2re feet additional on sIopes Total Available for Infiltration: 3103.114 square f'ee = 1472_378 ft3 Total Required Under County Standard: 731,3653 ft3 OK Hydrology ChEck: Rational Method: Pea k Rij noff, 90-year s#orm, Q=CIA Impervious Sur~ace C: 0.9 Pervious SurFace C: 4.25 10-year intens ity: 12 indhour Tirne oC concenkra#ion, 5 min. Area Impeavious, 33436.76 square feek Area Pervivus: 4898.245 square feet Peak 0: 2.30 cFs Peak Infiftration Rate- 0,36 inJhour Penrious 5ueface, nan-swafe: , 1595,13 square feet Peak Q. Perv, non-swale: 0.03 cfs 1nFltratian capacity, perv, nan swale• 0.0 1 cfs Peak Q, remainder: 2.28 cfs Swaie Infiltration Capacify, 00259 cf5 drywell infitration cap_ 0 3 cfs eElch (1 tatal) Storage Required, 5 minute Starm: 587,35 cubic feet Storage ,4va+lable, Swale Only: 1472378 cubic feet Plus Drywells. 54.45 cubie feet Total, 1526832 cubic ieel' DK Peak Runoff, 50-year starm, (5 minule) 50-year in[ensity: 501 inlhour Peak Q: 3.66 cfs Storage Required; 1075,18 cubEC feet 5wa1e PIuS Drywell; 1526-832 cub~c feet OK Raadway Basins: 1Nest End, fVorth and Sou#h 5itie5; (Mirrpr ImageS) Tokal Improved Impervious Stirface Area: 7031.$76 square feet. Asphaht Imperviaus Surface Area• Engcalci-G-10 _ r Bonuccelli ae+rel'opment Industrial Developmenk at Sullivan and Iv9arietta 2-Aug-00 TeehCon, anc. Prepared by Alan E_ Gay, P_E_ Sike Hydrology Skudy Design to 10 year stQrm (for review by Spokane County Engineers), new• 5159.04 square feet Roof: new: 0 square feet Sidewalk- new, 1872,$37 square feet UtiliFe bioiltration swale {grassy} for disposaP Assume antecedant sa$urated soil conditians: 1 Dr}+well necessary Available GEassy Area; 654,2942 square feet Qepressad Infilkration Area: 213.7647 square feet cultivated 5urface Additianal available infillration volume on side slopes. Assume 3'9 slapes 1.5 feet wide strip around depressfon Swale- 44d.5295 square feet; up ta BR available for storage on 3:1 slapes Tokal Available for Infiltra#ion: fVorfh: 654.2942 sCluare fee = 217.0147 ft3 Total Required Urader County S#andard: 214,96 ft3 Ok[ hlydrology Check° Rational Method: Peak Runoff, 10-year slorm, Q=CPA Impervi#us Surface C. 0_9 Pervious SurFace C. 0.25 10-year intensity: 3.2 inlhour Time of concentrativn: 1 min. Area Imperviaus: 7031.876 square feet Area Per,,;ous, 654_2942 square feet Peak Q: 0.48 cfs Peak Infiltrakion Rate: 036 infhour Pervious Surface, non-swale: 0 square feet F'eak Q, Rerv, non-savale: 0.00 cfs Infiltration capacity, perv, non swaEe: 0_00 cfs Peak Q. Eemainder: 0.48 cis Swale Infiltrakion Capacity: 0.0055 cfs Drytiveli infltrakin cap.; 0,3 cfs Storage Required, 5 minute Skorm: 51 44 cubic feek Storage Available, Swale Only: 217.0147 cubic feet PCus I]rywelL- 5445 cubic feet Tatal: 271 _469 cubic feet OK Peak Runoff, 50-year storm- (5 rninute) 50-year intensity' 5.1 iNhaur Peafc Q: 0.76 cfs Storage Required: 136.40 cubic feet OK Raadway Basins: Middle, hlprth and Sou#h Sides; (Mirrar Irnages} EngcaIC1-G-11 1 ` + • Bonuccelli Development Industrial Development at Sullivan and Marietta 2-Aug-00 TechCon, Inc. Prepared by Alan E. Gay, P E. Site Hydrology Study • Design to 10 year storm (for review by Spokane County Engineers). Total Improved Impervious Surface Area: 4654 square feet Asphalt Impervious SurFace Area: new: 3700 square feet Roof: new: 0 square feet Sidewalk: new: 954 square feet Utilize biofiltration swale (grassy) for disposal. Assume antecedant saturated soil conditions: no drywell necessary Available Grassy Area: 1090 square feet Depressed Infiltration Area: 30 square feet cultivated surface Additional available infiltration volume on side slopes: Assume 3:1 slopes 1.5 feet wide strip around depression Swale: 1060 square feet: up to 6" available for storage on 3.1 slopes Total Available for Infiltration: North: 1090 square fee = 692.5 ft3 Total Required Under County Standard: 154.1667 ft3 OK Hydrology Check: Rational Method: Peak Runoff, 10-year storm, Q=CIA Impervious SurFace C: 0.9 Pervious Surface C: 0.25 10-year intensity: 3.2 in/hour • 7ime of concentration: 1 min. Area Impervious: 4654 square feet Area Pervious: 1090 square feet Peak Q: 0.33 cfs Peak Infiltration Rate: 0.36 inlhour Pervious Surface, non-swale: 0 square feet Peak Q, perv, non-swale: 0.00 cfs Infiltration capacily, perv, non swale: 0.00 cfs Peak Q. remainder: 0.33 cfs Swale Infiltration Capacity: 0.0091 cfs Drywell infiltratin cap : 0 cfs Storage Required, 5 minute Storm: 95.59 cubic feet Storage Available, Swale Only: 692.5 cubic feet Plus Drywell: 0.00 cubic feet Total: 692 5 cubic feet OK Peak Runoff, 50-year storm: (5 minute) 50-year intensity: 5.1 inlhour Peak Q: 0.52 cfs Storage Required. Engcalc1-G-12 ~ ! f Bonuccelli De+relnpment Industrial Dewelopmer,[ aC Sullivan and Mlarietka 2-Aug-00 TechGan, Inc. - Prepared by Alan E. GaY, P-E- Site Fiydralogy Study ❑esign to 10 year s#orm (for review by Spokane Caunty Engineers) 153,97 cubfc feet O1C Raadway Basins: East End, North and Svuth Sides: (Mirrvr fmages) Total Improved Impervious Surface Area: 5054 square feet Asphalf kmpervious 5urface Area. new; 3561 square feet Raoi: new, 0 square feet Sidewalk: new. 1488.75 square feet Utilize biafiltratian syvale (grassy) for disposal. Assume antecedan4 saturated soil condi#ions: 1 Drywell Fs,vailable Grassy Area: 2000 square feet ❑epressed Infiftration Area: 18 square feet cultivated surface Addikional a+railable infiltrakion valurne on side slopes: Assurne 3:1 slvpes 1.5 feet wide strip arpund depres$ian Swale- 1982 square feet' up to 6" available fpr storage on 3' 1 slapes Total Available for Infilkration: Norkh• 2000 square Fee = 504 5 f#,3 Total Required Under County Skandard. 148.3854 ft3 D}C Hydrolagy Che& Rational Methad: Peak Runoff, 10-year storm, Q=CIA Impervious Surface C: 0.9 Pervious Surface C: 0.25 10-year ir tensity: 3.2 inlhaur Tkme of canceritration: 1 min, Area Impervivus: 5050 square feet . Area Pervious: 2000 square feet Peak Q- 4.37 cfs Pealc InFltra#idn Ftate= 0.36 inlhour Perviaus 5urface, non-swale: 0 square feet Peak Q, perv, nan-swale: 0_00 cfs Infiltration capacity, Perv, nan swale: 0,00 cfs Qeak q, remaindeT: 0,37 CFS Swa3e Infiltratian Capaq-,iky: 0.0167 cfs drywell infiltratin cap.; 0 cfs Storage F2equired, 5 minute Starm: i08_46 cubic feet Storage A,vailable, Swale Clnly. 5045 cubic feet PRus arywell• O.00 cubic feet Tota[• 504_5 cubic feet DIC Pealc Ruroff, 50-year stcrrn: (5 minute) Engcalc1-G-13 Bonuccelli Development Industnal Development at Sullivan and Marietta 2-Aug-00 TechCon, Inc Prepared by Alan E. Gay, P.E. Site Hydrology Study Design to 10 year storm (for review by Spokane County Engineers). 50-year intensity: 5 1 in/hour Peak Q: 0.59 cfs Storage Required: 174.48 cubic feet OK Existing Pre-developed Site Total Improved Impervious Surface Area: 0 square feet Asphalt Impervious Surface Area: new: 0 square feet Roof: new: 0 square feet Sidewalk• new: 0 square feet Available Grassy Area, 921278 square feet Depressed Infiltration Area: 0 square feet cultivated surface Additional available infiltration volume on side slopes: Assume 3:1 slopes 0 feet wide strip around depression Swale: . 0 square feet: up to 6" available for storage on 3:1 slopes Total Available for Infiltration: Norlh: 0 square fee = 0 ft3 Total Required Under County Standard: 0 ft3 OK Hydrology Check• Rational Method: SCS Method : Peak Runoff, 10-year storm, Q=CIA 24 hour storm Impervious Surface C: 0.9 Tc = 25.26 minutes Pervious Surface C: 0.25 Total Area 21.15 acres 10-year intensity: 0.9 in/hour Time of concentration: 36.2 min. Area Impervious: 0 square feet SCS curve No. 61 Area Pervious: 921278 square feet 10-year 24 hour storm Peak Q: 4.76 cfs 2.12 inches SCS Type II Storm Peak Infiltration Rate: 0.36 in/hour SCS 100 Hydrograph Peroious Surface, non-swale: 921278 square feet simulate capacity of drywell as Peak Q, perv, non-swale: 0.75 foot diameter orifice (no drywell) 4 76 cfs Infiltration capacity, perv, non swale. Capacity is adequate. 7.68 cfs Hydraulic Capacity of Drywell is Peak Q, remainder: 0 cfs 0.00 cfs Peak flow: 0.08 cfs Swale Infiltration Capacity: 0.0000 cfs Engcalcl-G-14