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27229 PE-1684E RIDGEMONT EST NS P C] le- A,.. IV E C) U T"T - Y OFFICE OF THE COUNTY ENGINEER ■ Ronald C. Hormann, P.E., County Engineer A DrvpioN OF THE PUBLIC WORKS DEPARTMENT Demos M. Scott, P E., Director January 3, 1995 Kevin McMulkin, P.E. Simpson Engineers, Inc. N. 909 Argonne Rd. Spokane, WA 99212 Subject: Ridgemont Estates North 6th Addition Review #1 Spokane County No. P-1484E Dear Kevin: A review of the road and drainage plans for this project has been accomplished. Areas of concern to us are indicated in red on the attached prints and calculations. Please make the corrections and resubmit them to this office in order that the review process may proceed. Please provide 2 copies of plans and calculations for the project with each submittal. If you have any questions about this review, please contact us at 456-3600. Thank you. Sincerely, Spokane County Engineers Dean Franz, P.E. Plans Review Engineer encls: Plans (1 set) Calculations (l copy) Comments (3 pages) cc: project file dl, 1026 W Broadway Ave • Spokane, WA 94260-0170 • (509) 456-3600 FAX (509) 324-3478 TDD• (509) 324-3166 1. 2. 3. 4. S. 6. d 7. i i i 8. i s i 1. 2. 3. EASEMENTS Adequate drainage easements are shown for maintenance of drainage ditches or pipe systems. There are easements, proposed or existing for natural channels which cross the property. An easement was provided wherd street drainage was diverted onto private property. The perpetual maintenance of private systems has properly been provided for. The maintenance of drainage systems within Spokane County ROW has been properly provided for. Appropriate drainage language has been provided by the reviewing engineer to the surveyor andrkr engineer who is involved with the platting wo. Pre-existing drainage easements on this parcel are not affected by,this plat overflow easements are provided from swales/ponds located in low points 4. 5. 6 MISCELLANEOUS QC check of review completed(date) (init.) Bond quantities for drainage item calculated (date) (init.) Vertical curve sight distance worksheets done (date) (init.) Vertical curve geometry worksheets done (date) (init.) Drainage volume worksheets done (date) (init.) Stamped road mylars to Permit Tech. (Sylvia/Suzanne) Stamped lot plans, to Admin. Asst. (Sandy) 19 7_ r_k.li-,tv3 OEAu993 DRAINAGE PLANS (cony d) 16. 17. 18. Pipe materials meet county standards for systems that lie within county ROW. (Note: The type of pipe in private systems may be as specified by the design engineer) The culverts shown are properly stationed from centerline stationing. Odes the drainage system configuration avoid conflicts with underground utilities? 19. is there a need for energy dissipation on any of the culvert outlets shown on the plans? 20. Is there a need for rip rap around the culvert outlet at any of the culverts as proposed on the drainage plans. 21. 22. The rip rap that is shown for the drainage plans is adequate for the culverts where erosion is a concern and the engineer has submitted acceptable rip rap design calculations. Pipe anchors are shown for pipe grades greater than 150. 23. There are no instances where water is trapped against a fill with no culvert shown. 24. Profiles and cross sections are shown on the plans for all proposed channels and ditches. 25. Ditches with eroding velocities have a proper lining for erosion protection. 26. Water will properly flow from an existing or proposed ditch on to the pavement as proposed on the drainage plans. 27. Where the ditch profile passes from cut to fill the flow has been properly disposed of. 18 Cklistv3 O/Aut993 DRAINAGE PLANS ( cost' d) 4. 5. 6. 7. 8. 9. 10. The designer has provided a letter from the pipe manufacturer certifying that the intended pipe is suitable for coven less than ' (PVC) has provided RCP), 1' (HLlPE1AI7S) or the engineer pipe bedding for trench details for upgraded these areas The minimum velocity within the pipe system is 4 feet per second at design flow in a backwater condition. (Note: The County Engineer may permit lower velocities) calculations show a minimum The backwater freeboard of 0.75 feet for each catch basin or manhole. vert The minimum et for ex eed PtY i5 standard . 0.5% and all pipes me All angle Points in the storm sewer system have suitable access such as a manhole for cleaning. At locations where'ltwo different pipe sizes enter the same manhole the 4.8 diameter points of each pipe are at the same elevation. (Note: Exception allowed for drop manholes) 11. is there any downsizing of pipes in a systems of pipes that are 181'' in diameter and smaller. There is a downsizing of pipes in the amount of 311 for a minimum of 103 feet in a pipe system that contains pipes that over 18" in diameter. All pipes in the pipe system are 12" and larger as per Spokane County Standards; (10" pipe that is allowed for connection of inlets to catch basins or drywells, if the length does not exceed 44 LF and the velocity is at least 4 fps). All storm sewer pipes are located a minimum of 5 feet from a reak or side property line and have adequate easements for maintenance. Inlets on the same slope are located es fthatdQhe maximum width of spread for the gu not exceed 6' (from curb face for Type "A" or "R") „g~, , from back of curb for Type 1 12 . 13. 14. 15. The plans and profiles show all culvert pipe types, stations, offsets, lengths, and inverts 17 ,-L-1 -tv3 ❑JAug93 DRAINAGE PLAINS (cant' d) V 18. The invert at the curb inlet is at or above the max. water surface elevation for the design storm 19. Filter fabric is specified for the gravel envelope around the drywell - is specified between the drywell and the gravel envelope installation specification is adequate. 20. Irrigation plan for County-maintained 208 swales Lot plans submitted on )J c- 208 LOT PLANS 1. Lot plans are requirled; submitted on 2. The 208 lot plans show: the lot number, block number, subdivision name, date drawn,, scale, and north arrow. dimensions to lot1corners drainage easements setback requirements swale floor elevation scale floor dimensions rim elevation if drywells are present curb cut station, offset, invert and length any drainage ditches shows depth from the top of the curb an attached cross section of the Swale or ditch 3. Lot plans have been stamped by a professional - engineer on all pages 4. Lot plans are of sufficient scale to maximize the lot size to the 8 1/2" x 111" paper size. (Drawings may be on plain white paper) 5. 208 lot plans were approved on CULVERTS AND PIPE SYSTEMS 1. The road culverts are at the low points of stream flow. 2. The headwater was calculated for culvert entrances and is under 2 diameters for culverts under 18° in diameter and 1.5 diameters for culverts greater than 18". 3. There is a minimum of 12" of cover for all culverts and storm sewer pipes 16 ckliacu3 OjAu993 DRAINAGE PLANS (coa't' d) 8. Soil. type is appropriate for drywells (pert rate 7211/hr) if not: ga. overflow from a Swale at a low point will be directed away from building pads by an identified easement over improved ground an existing natural' drainage channel covered by an easement g. Drywell location does not conflict with underground utilities. 10. Drywell type is specified. 11. Drywell grate type is specified ('type 3 -std. detail D-7) 12. Drywell grate elevation is: below the invert at the curb inlet between 611 and 8" above the swale floor elevation II 13. Does the note. „Wrap the drywell with a filter fabric (Amoco 4545 or equivalent)" appear on the plans? 14. Swale floor elevatiion is: specified , between 611 and $1' below the drywell grate elevation at least 6" below the normal gutter flowline at the curb inlet for Swale withouta dry-well line at at least. 8" below the normal gutter the curb inlet for swale with a drywell 15. Swale floor dimensions are shown minimum area is shown i ~ the area matches the required area from the 208 calculation for impervious areas. 15. Basements for the 208. are shown on the drainage plans are shown on the subdivision plat i are of adequate size to contain at least 6" freeboard above the max. water surface elevation 1 for the design storm are tied to the lot corners. 17. The side of the swale that is the furthest distance from the street should have a top of Swale elevation that is higher than the highest water level of the swale. 15 ckIIOLt3 011--93 DRAINAGE PLANS [cunt' d] 8. 9. 10. 11 12. A curb cut detail is shown on the plans with the new county back drop with transitions and a 211 depression for curb cuts inside county ROW, or referenced to SCRS std. detail B-15 The plans shows acceptable curb cut details and grate details for installations which lie within private road easements. If inlets are in a gravel road or a dirt ditch a 6' x 61 A.C. apron is shown around the inlet. Catch basin or special manhole details are shown or a standard drawing is specified. Critical low points in the drainage system have been provided with ioverflow easements. 208 SWALE SYSTEMS 1. 2. 3. 4. q 5. i w i 6. Is the swale located outside a future set aside area? See Findings, and Order for where setasides are required- The swale bottom and sides have sod or grass turf specified. Swale side slopes do not exceed a 3:1 side slope. 2 1211 deep., Should onlyfbe swale depth is allowed where less than constrained by obstacles) If depth of water from bottom to drywell rim is between 6 and 8 inches, soil mixture has been specified which meets Spokane County Guidelines. Orywell is: located within 8 feet of the curb line, or a maintenance access route and easement are provided Drywell stationing is staggered from the inlet by at least 4' 7. Multiple drywells are located more (center--center) apart than 30' 14 ciklioty} O/Aug93 DRAINAGE PLANS (cont'd) 11. Does the 100-year 12. Does the the desi; 13. -is the m, "B" less entire plat lie outside of designated Flood Plain Area? entire plat lie outside of Zone "B" of 3nated Flood Plain Area? ax. street ponding in any part of a Zane than 1'? 14. Does the pleat contain appropriate language limiting the lowermist opening in a structure located in a Zone "Bill to not less than 11 above the lowest road elevation? 15. The drainage concept,i.s compatible with planning commission requirements. 116. The difference between present and future flows is retained on the site. INLETS 1. The inlets shown are within the stream flow. 2. inlets are shown on the low side of a road or at the low point of a vertical curve 3. Curb type inlets are shown at sags and are properly sized. Perimeter does not include the side of the - grate against the curb face (all grate types). Perimeter is divided by 2 for calculations where no curb opening (Type 1) is provided. Area r clear area - 2 for Type 1 grates) 4. There are no long curves with flat grades which pose a problem. 5. The centerline road stations, offsets, and invert elevations for all inlets are shown on: plans profile. 6. Grate type is shown on the plan and is acceptable. (Spokane County Standard inlets in county ROW, on private property other inlet type may be specified) (Type 1: D-2; Type 2: D-4) 7. A detail drawing of the grate/curb installation is shown on the plans and includes the 2" depression and transitions as per county 11 standards for grates that are located within county ROW, or referenced to SCRS std. detail D-8 13 ckl xsstv3 o/Aug93 DRAINAGE PLANS ( coat' d) UNDERGROUND GRAVEL GALLERIES 11 1. .3 void ratio for gravel free space volume is used 2. Perc rate from field test is used to develop outflow rate 3. 1o-yr event volume is contained entirely underground 4. 100-yr event volume is contained by a combination of underground storage and above ground storage up to 8" depth of u round storage 5. f8-ndergrand storage canda above g o exceeding 8" depth 5a. soil mixture is specified for water depth in pond exceeding 8" 6. Entire gallery is gapped in filter fabric CoNvEYANCE Conveyance - pipes ditches tter hei ht gutter flow depth is less than gu g Backwater - pipes, ditches headwater culverts curb drop/curb inlets on grade (fig 16), sump (fig 17) Grates - sump (fig 15), continuous grade (fig 16) Riprap - stone gradation, pad dimensions 7. Soils type is "p'„re-approved" (Garrison, etc.,) i for drywells without percolation tests 8. Does the drainage report identify the SCS soil groups for the project area and for the proposed roads to be built in the protect area. 9. The drainage design maintains sheet flow patterns in natural watercourses i i 10. The drainage design maintains existing sheet ow patterns without concentrating flows 12 ck1,0tv3 o/Au993 0I DRAINAGE PLANS 1. Has a plat map been submitted which shows lot dimensions, street widths, etc.? 2. Was a map with contours spot elevations submitted to properly determine drainage basins? 3. were all existing drainage courses shown? 4. Were all the proposed drainage courses shown? 5. Were Hydrologic calculations submitted for each basin? (Bowstring if area s 10 acres, SCS TR-55 if area > 10 acres) Offsite (50-yr storm if undeveloped, 10-yr storm if developed) Onsite (10-yr storm) Q for entire area Q for roads only INFILTRATION POND Actual pond volume provided DETENTION POND Release to pipe system: contain 50-yr developed release at 50-yr pre-developed secondary overflow to pipe in control structure for 100-yr developed emergency overflow weir for 100-yr developed sump prior to outlet to control structure 1' min. freeboard grassed sides/floor for publicly-maintained ponds sprinkler system for publicly-maintained ponds Retained on site, no drywell: contain 100-yr'developed emergency overflow for 100-yr developed 208 SWALES 208 swale floor,area, volume requirements 208 swale floor area provided 208 swale volume provided ck115tv3 0/Au993 ROAD PLANS (coot' d) 23. DRIVEWAYS 23a. can a driveway slope of 80 or less be maintained between the edge of :pavement and the right-of-11 way? 23b. Can the driveway less be between right-of -way and the building ~setback line? 10 Ckj,.,tv3 olAug93 RprpLMS ( cant' d) 18f 18f. 7k 3.9 . 19a. 19b. 20. 2Da. 4- 2Db. the required 51x5' landing zone at the bottom of the ramp is located inside of a line drawn 1' inside a lane extended between the curb faces of the adjoining street at intersections? any drainage structures are located outside of the landing zone? 20d. The intersection horizontal sight distance analysis shows that sight triangle encroachment on private property is 2' or less 21. Is there a need for slope easements? 22. Is there a need fir erosion protection? 9 eklissty) ❑Jnu993 ECR, MCR, and ECR elevations are set so that the superelevation between the intersection and the curbline is banked properly for right-hand turns into and out of the 'intersection roads (the road slopes from the intersection down to the flowline) ECR, MCR, and ECR elevations at intersections without stop sign control are set so that the superelevation between the intersection and the curbline does not exceed: (ref. AASHTC) 10!- (flat terrain) 8% (rolling terrain) 6% (mountainous terrain) CUL-DE-SACS The cul-de-sac grades (top of curb) meet county cul-de-sac standards (la min.) The cul-de-sac curb is shown in profile INTERSECTIONS ~ ride Do the intersections meet the 20 g requirements? Wheelchair rannps are provided at intersections with sidewalks 20c. If there is a change of direction at the wheelchair ramps, are the ramps oriented so that: a 51x5' pad is provided at the top of the ramp? 13h. if curb grades are below 0.8%, has a special note been added which requires a licensed land surveyor to verify that the curb forms are at the correct plan grade prior to construction? 14. Has an "R" v lue test been performed for each soil. group? 14a. The pavement section is adequate for the R-value A Traffic index for the road type lif ~ o 01R C on t' RO PLANS (d) an is. Locations where water is intended to flow through an inlet or curb cut are at the low point in vertical curve 16a. stop signs are shown for all streets which intersect an arterial (Check with County Traffic Engineer if there is a question) 16b. street name signs are shown at all intersecting streets 16c. is there a need for barriers at the end of dead end streets? 16d. is there a need for other special signing? (Check with the County Traffic Engineer) X 17. 18. 18a. Has the Eire District approved all proposed private road turnarounds that are substandard according to our Spokane County Road Standards? CURB RETURNS Ih Are BCR, MCR, and ECR stations/elevations on curb returns shown on the plan? in the profile? 18b. Are the curb return elevations correct? I 18c is there positive drainage from the road intersection to the MCR? 18d. Curb return radius meets County Standard minimum of 20' (to back of curb for rolled/wedge curbs, to face for vertical curb face types) 18e. BCR, MCR, and ECR elevations are set to allow drainage from the centerline to the curbline ck]iatva O/Au993 8 ROAD PLANS (cont'd) 12i. A 411-wide, white painted fogline at 12" from the edge of paving is indicated (tapers or tangents) 12j. Are the curb grades above the county minimum of 0.8%? 12k. if curb grades are below O.86, has a special note been added which requires a licensed land surveyor to verify that the curb forms are at the correct plan grade prior to construction? 13. NEW STREETS 13a. Does the proposed alignment meet Spokane County Standards? vertical slopes vertical curve length horizontal curve radius intersection separation 154)' on local access 13b. The plans show the typical cross section for streets 13c. Does the proposed street width snatch the Findings and Order? 13d. The cross-section shows: existing RAW proposed RAW future setaside 13e. Does the typical section on the plans meet Spokane County Road Standards? cross slope is shown cross slope is within standards cross slope is correct when checked on profile 13f. Cu t •e. s own proper type for the road classification meets Spokane County Road Standards for curbs I within the public right-of-way ,f consistent with the curb type in the general area 13g. Are the curb grades above the county minimum of 0.80? 300' ❑n arterials 7 ckl.x Bt ~1 O)Aug43 RprplamS ( cant' d NNWX-- 6. Is the bench mark shown on the plans? 7. Are stationing equations shown? 8. is stationing correct (south to north, west to east, reading left to right on the plan)? 9. Are existing utilities shown on the plans (or an information copy of the utility plans submitted)? 10. Are proposed utilities shown on the plans (or an information copy of the utility plans submitted)? 11. Does the note "Any conflicting utilities shall be relocated prior to construction of roads or drainage facilities." appear on the plans? 12, STREET WIDENING ~C 12a. Are curb design sheets provided for widening of existing streets? 12b. Does the curb design conform to Spokane County Standards of section cross slope (Between 2% and 4.5%-)? 12c. Is there a street cross section shown for widening existing streets? 12d. Does the proposed new width match the width required in the Findings and Order? 12e. The cross-section shows: existing R/W proposed R/W future setaside 12f. 1001 (min.) pavement taper into project is shown (1) There is adequate R/W for the taper to extend from the new paving width to existing pavement. (2) There is inadequate R/W for the taper to extend from the new paving width to existing pavement; taper extends from existing paving to R/W. 12g. Length of pavement taper out of project meets: WS2 - 60 for design speeds s 40 mph WS for design speeds 7 45 mph ft. min. taper length approved by County Traffic Engineer 12h. Transition from end of curb to existing paving is shown (curb should nose down in 121+) K ROAD PLANS 1. List any roads that must be designed and constructed on the project. ROAD REQ'D WIDTH DESIGN MIN./MAX. STOPPING SIGHT MIN. CURVE NAME CLASS. PAVED R W LF-RRAIN SPEED GRADE DISTANCE HORIZ. VERT. Asp of `j A~^rL 2. Planning conditions require submission of a landscape plan. (NOTE; Usually associated with PUD' s ) 3. I have checked the landscape plan against the road and storm drainage design and there are the following conflicts: 4. The following road plans have a bearing on the design of roads for .his project and a copy is in h f'le• t e ~ . f~ it 1l rr , P,-A, $r 5. I have sent an "R value and percolation test request to the Construction Section with soils information and a layout of the project. `+R" value test request to Designer (date) . GENERAL ITEMS (cont'd) 24. List any design devIiation requests and their l~, status: 25. Locate the Findings list any unusual cc f RVP 1 b OEr~ CAt&,Rn 23. Eackcheck of previo 24. All previous commen i Order f or the project and tions: s comments completed s adequately addressed 3 r y6t, to ° 0/4 GENERAL ITEMS (coot"d) 10. The calculations are bound together are stamped and signed 11. The plans and calculations Engineer by a Professional 12. The developer has signed and approved the road and drainage plans 13. Are there any conflicts between the proposed drainage ditches on the plat drainfields and any 14. Bowstring calculations by developer are in the file for this review. 15. Vertical curve stopping sight distance re in file for this calculations by developer a review nin sight 16. Horizontal & vertical ~~i 1e for tthis are calculations by develop review 17. The engineer/developer has provided evidence of ic utility servicing coordination with the electr the project 18a. The file contains a Spokane County Section Map 18b. The file contains a Spokane County Assessors's Map 18c. The file contains an aerial photo of the proposed project area 18d. The file contains a corrected preliminary of the final plat map 19. The project is located in urban boundary area 20. The project is located in the Aquifer Sensitive Area 21. The project plan name matches the plat name i 22. Is the entire project located outside of an ? identified Flood Plain Area 23, is the entire project is located outside o an r Management Problem Area? i identified Stormwate 2 ,r J SUBMITTAL CHECKLIST PROJECT # REVIEW REVIEWER: DATE: IZE PROJECT: TEL # PROJECT SPONSOR: PROJECT ENGINEER (Road & Drainage Plans]i TEL ~r l3a PROJECT SURVEYOR (Plat) TEL GENERAL ITEMS YES NO N/A 1. The $100.00 fee far plat review has been paid to Spokane County for this submittal x 2. An agreement to pay fees has been submitted to Development Engineering Services 3, The fee agreement has been signed by the project firm ' If . s owner or a principal of the developer written signed by an agent of the owner, attached to the i s authorization from the owner fee agreement ( 4. Review fee account is current (no invoices over 30 days outstanding) S, 1 have noted the plans in, plans out dates on-the pink sheet in the file 6. If the project is a mobile home park, were the plans reviewed by Planning? 7. 2 copies of the plans were submitted A i r . copies of the calculations were submitted 9. The plans are on 241' x 3511 sheets w 0 w 0 0 0 u / u / ~ ~ --guitd~h9 80.00 v LLJ w o w W . 0 • N O 0 r z 5 e .t6ack-- . ~ 80.00' Ld a w''^^ 0 0 Z 3 80.00' • 17TH 3+60 . Nl•S~ - -.;~o , ~3 ? 162.50 S89'23'17"E y'~ ~o S89 2317 - E Gsy yo.~o • 105.00' rc. 3 No.7.g3 ~ O g3 - 1 W r--- 00 j I'7 1 1 ~ t oo ~ cQ rn i cQ re) 1 LO Exhibit A-1, continued: Hydrologic sail groups for United States soils IAEfsr c l fUL SKEAA C l GAPCDr 1 Gib FAf9STQNF C I f"I10kf C I GAPO 0 C 1 GIL$SPif a IFRke1RrN a d PULTo N D d GaPO. 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D 6 I LANG GAAA 1 D 1 GEPQAUp a l " [q A p FAI]r" L I CAItit$ C (GyGWE~r(~ a Y G EG INC. r l L OS lCft GAt C FAIPR 1,6■INt51C44 C I '1 TI I ' G9ALACN D I GL.PrIN ■ FRISCO 8 I.4aIwE8V[Lli A l GEaLAwf 1 d GLaSGp■ C fNISdIC d ! GAL+IA D 14/RA13,]A f 1 GLNLC 4 d GL.SS*.CA p f4[Tt. 11 1 G BwETN I CARPC'CnaL1:5 D 1 49 w NakTDrN 1 d GL'AN a Fg111 ELL C 1414E CNIFIj a C k (.-R l I C.AeICK r k GCAw•Ar / 1 4LE.SaN e {A0UCP4 D 1 GALE k C I GERNEF C 1 GL ttf C FAODO I GALtn ; vl A 1 aup. r I GfAa ! 1 GLfN FWa4M■w L 144VtPP1 1' d 4 .Cr lit N O d aS LtArrp C 1 4Lfr+a.P 1 FGOL IC 9 I G.LLSI l+r. 1 L { 4AAMIN tll al GEAN►AD. DQ&IN iLr f 1 GLFNB.ii. t 1 C C "')L1C. C I GaLf $1r1VA a 4 G•Ft'• l G/E rNa p l D 1 GEA}1 a d GLtmoci.G a LEYa11QN[3Q0] I GALtT b 1 GwS [4 4 Sfle E I 6LtkpLA1A f +gQLIC. FLUI)aen r I C.L ILfE C EfL I GASrf: N4P• 4 1 C 4 Si NfR 04001 CL!NpAOQa D fgpn{.ORF a l 4A4. di1fQ ` I G4Shc p d GE81PlM 0 I GL!hCAWp F FROM TE N.C S i 4ALkiFRO. C d :.ASGGLr P d Gf14rw0 0 [ 4LCACAAp. rCl. C FAQNrIfw C k SALlN:-.LKaLI I GABSarAT 1 GfTCNCLL C 1 3aLI++f ''O'raN G ! 46LL4n40 " GAsSV1LL; a I GCTKAIL a 1 GLCwCO r ~D FRGSr l ~ALL•rrN C 1 LA'1QTI C I C Gfrr ri C d GLEnCRt. PQ+rOfp Q ►A4dAA0 C r G■LL1_GQS C I Gat A 1 4rTd c p l GL£NaiLf 0 FNUITA a I L■LLfN ti 1 . r r £c Gt C! 4LtND.Lf. bLI FAUITF+ELD a + GALLI■ ! at G SSCA f r GETStIa C ! GLCwD.L6. AApiLT C f4Ul1n4AST _ C l ® l CAI C 1 Gd014CR C d FLpaDFD FPUIIL■r.a 7 I G/LLIQ+'! 91, 0 1 41100.1 0 1 GLLADER}QN a F ANP. £ I GALLNaK tl d' 4ATt ii+Dd? 1 C G+tl1aNSCA£fa C I LLENDIrE a .a ATELO rCI -60 I G+LLVP It 1 GAIL14 I Glans a l GLCNODA• aID F9u 11L&NO. 0 1 C I GA"O CIOI GrIQA a l GIs atv C I GLt+af DE+a p FA WE C 1 GALL D 1 I L 0 1 1:10S"VILLf p d LLtNiLG e F4rFyUA4 0 1 G06 wA r a 1iN I' I GlBMELL C I GLZNF GAD FI. gPLrr C I 4/L rEiiL'1. k GAUL AT 6 I LIDtON C 1 4LENNaLL C Fr. Gag CO. a I 4+L V•,2 a C 1 4ALlt,[ C I GIf LD• C I GLt nr.aw 0 FOCAA S ! GALYIN A I G r t tL I GArILAk C l 4dFFDNa O k GLiN-•r 1 FVP`aLt 4 1 44tigst a 1 GAMINS C d Gl4GfA C 1 LLE ti~ ■ L iuEC3 C I G.+tL$4 ; 14601PT4 D + GILT tl ! 4Ltw;..tir L FutcGIT■ a d 4w.1tl04 1• i 6•Y D 1 6&L1fAr a d 6LiNDr4 0 Fuca* C I GaN4Cf C 14aYLtSYIi LS 0/a1 G1L1aa 4 1 GLtNPQOL a •u4wrf€ 1 k G.NAD11 a . ! G■ LuR T a 4 ~I 61L1I 0 1 GLENAIa D ruG"tS C I 4aNCE C 1 G C I nP 4lLCIiT ■ 1 GLEkitaiL a /ULCNiR F C I GAka4 a GAVVIL d L£ L I GdLLD tl k GLinAa}} D p4 C-10 , GAryii 0 ! GA;e LLt D 1 IILCWEii l GLf P. p f UL L A 0 C d GWwtTT a ! GACgi p ! GlLfaa C C I GLt 10. NDN 4 4 L ► ; P F $ d 414"514914 L d 4AtrrLL C 1 GIL£i 0 1 4LtNraN. r+t.t L F~+LLtATON aV d GaNSnIW. P4NpkC D I GtALwaAf C l 41LPOAD 11/DI 4LIKIOSN a FuLr+fii a l 6..+r 0 1 G(wWr a l GdLIC'a0. D I GLCkrICa 1 #WLACA. QAAINLQ C I L4p541 TE lI ! GE1}C:N as SIAA IIF fCA k GLiwYILL1: C r 1 I M1514■ 1Ur+ d GLCAVDN p Appendix A: Hydrologic soil groups Soils are classified into hydrologic soil groups (HSG's) to indicate the minimum rate of infiltration obtained for bare sail after prolonged wetting. The HSC's, which are A, I3, C, and D, are one element used in determining runoff curve numbers (see chapter For the convenience of TR•55 users, exhibit A•1 lists the HSG classification of United States soils. In e^Nbzt A•1, some of the listed soils have an added mndifier; for example, "Abrazo, gravelly." This refers to a gravelly phase of the Abrazo series that is fond in SCS soil map legends. Disturbed soil profiles The infiltration rate is the rate at which water enters the soil at the soil surface. It is controlled by surface conditions. HSC also indicates the transmission rate-the rate at which the ►vater moves within the soil. This rate is controlled by the soil profile. ApproNimate numenc•al ranges for transmission rates bho%%,n in the HSC definitions were first published by Musgrave (USDA 1955). The four groups are defined by SCS soil scientists as follows: Group A soils have low runoff potential and high infiltration rates even %vhen thoroughly wetted. They consist chiefly of deep, well to excessively drained sands or gravels and have a high rate of water transmission (greater than 0.31) in/hr). Group $ soils have moderate infiltration rates when thoroughly wetted and consist chiefly of moderately deep to deep, moderately well to well drained soils "'ith moderately fine to moderately coarse textures. These soils have a moderate rate of water transmission (0.15.0.30 in/hr). Group C sods have low infiltration rates when thoroughly wetted and consist chiefly of soils with a layer that impedes downward movement of water and soils with moderately fine to fine texture. These sails have a low rate of water transmission (0.05-0.15 in/hr). Group D soils have high runoff potential. They have verv low infiltration rates when thoroughly wetted and consist chiefly of clay soils with a high swelling potential, soils with a permanent high water table, Soils %vith a cla~Tan or clay layer at or near the surface, and shallow boils over nearly impervious material. These soils have a verv low rate of water transmission (0-0.05 inJlir). - As al result of urbanization, the soil profile may be conbiderably altered and -the listed group class,i[ication may no longer apply. In these circtiimstances, use the following to determine HSC accui{ding to the texture of the new surface soil, provided that significant compaction has not occurred (I3rakensiek .ind Rawls 1983): HSO Soil [eXtures A Sand, loamy sand, or sandy loam B Silt loam or loam C Sandy clay loam D Clay loam, silty clay loam, sandy cl iv, silty clay, or clay Drainage and &n•oup D soils Sumer Sods in the list are in group D because of a high water table that creates a (h-ainage problem. Once these soils are effectively drained, they are placed in it different group. For example, Ackerman soil is classified as AID. This indicates that the draine-d Ackerman soil is in group A and the undrained soil is in group D. (210•VI•TR.55. Second Ed., Ji 11 ne 1986) A-1 t: 1 SPOKANE' COUNTY isopluvials of IQ year 24 hour precipitation in tenths of an inch. a . 20 4 26 Z6 Doer Park i IB ` 3O ' P6 SPOKAIYL 1t Gi N ' 2 ! Chgney F SP ngle I 2U Lalah I8 1 b-6 i i I FIGURE 4 Sheet 1 of 2 r. k `J RATIONAL FORMULA DATE = 10/7/94 DESIGNER = K W PROJECT NAME = R.E. NORTH 6TH ADD. DESCRIPTION = STORMWATER DRAINAGE SUBAREA 1 = .24 ACRES SUBAREA TOTAL AREA = .24 ACRES COMPOSITE OVERLAND FLOW VALUES Ct = .15 L = c.) N .4 S .01 CHANNEL FLOW VALUES L - 772 Z 1 = .172 ^ Z i = ~:6 N - .016 B w [_1 S - .007 TD = .163 COMPUTED VALUES DUR - 5.00 I1C) - 7.18 010 .69 QA = .fag C~1R$ 0?fGNIMG AT LbW PvIN-T I SIP,, ' x 0 .Cn1 ~Cdt0.l ~nei~ln of o~~ 1 ~L = 6.1 CQ 3 Q 0.69 CFs ~otdl ee0.k rQAp- oi[ 3/7 h 3.vla-l [4)3I v.163~j/- YDROLOGY CMULKIN BASIN "C" PAVT. 1 RUNOFF COEFFICIENT = .9 RUNOFF COEFFICIENT = .9 ltg8.~$ enirarie,e I o w z 0.2.4r C a 3.~-v FI• ' ~ d C.uY-~ a?~~►~ ; 4 w; ~eed ~J - BDW aTR I NO C: ALCULF)T I ONS DATE 9/78/94 DESIGNER = K W P'CMLJLKIN D^51N "C" PROJECT NAME = RE NOF"TH ~jTH ADO. DESC R I PT T ON = STORMG4(- TE_R' DRA I NPO k t- I[itC nsi Ly Odev. vi n VC,Ltt stc)r 7gp !m,1n. l (Sec. D ti n. /hr. l {c:.-F.s. ? tLu, ft.) (cui ft. 7 (ctk. ft, ] it .r'rCs 1C3 c,U6 2 rril. 900 11 10. 0 600 2. i4 3. S6 2264 1 BOO 1('164 14.2 f3'52' . 87, . ~?2 7 2 5 tti I 774 15.0 900 1.77 2.81 =4B 2700 640 20.0 12cl0 1.45 2.711 7'4 4 77,600 -166 2S. n 1500 4 a 21 L 1 a 9 _i ~l CIs 500 1057 70, C) I GO() r 1.04 1. 6 74 i5 540C) -191:4' 75.0 ' 100 .?1 1 u 41 '4 a 7 6 _ 000 2R4T I C), CI 24r_ir_r C4.4 1.70 : 50 / 7200 7-69- Ci w' f0 f] 74 1E3 0 11'3f1 0 C~ 6. JJ. c_ 300 .64 1 . 02 Z7,6 5 77 9900 _6247 60. C) 7.60C.) .61 .97 7,772 10900 -7028 6t;. 0 _ 900 . 60 95 3V64 1 17CrCr -71 ,6 70. 0 4200 . _ 6 . 92 4140 1260C) -8460 75.0 415C)0 .56 .80 4227 1 W J00 -92.: 8c )r [wr 4SQ0 . l . 04 4289 1440C) _101 11 5100 . 5,2 . 8'2 I 90. 0 5400 . 50 .79 4 ' 2 16200 -1 1677 95. 6 15 700 .49 .72 4666 17100 -1 2 4,:14 100. 0 6000 .49 .76 4ACIO 1 G0 C) C) --1 7200 1-H E MAXI MUM STORAGE IS 11 ')T.59241 CIJ. 1-T. The ti me o F ccnr" en Cr a L i crn :L<; 14. 197FJ Iinx rsut 0s. The Unde veloped "r I ow out is ' c.+.5. TEN YEAR STORK C,ALC RATIONAL F-fli s;l1U1 H'r'I7ROLCMY i1i`k 9/ 2 3/9zj D 13 1:0 IgEI = F" W k [~I"1[JI_F' 1 !V 1 F'k°~ C (V C" PF 'O,l C, T Pk~P'[l_ = F,'. F ~'~J(IR T FR T6a~ °F ~H Ta=~0C)I.~ D;-r!(-R P 1 r ~I CIN 5 ] CJR VJA I FR k~F 1A .1 ]Vh"LJ C_ :auSAF." E!1 1 = 1 ~ 10' Ai'REE; 9liBik=i R F A j I`iUNf_1F C:(: 1-Fl= T C; I FNT r m °x 2, AClik_'a3, SUBPARFA Ri 1P ICjf° F C(3E!° 0= [ L: I I-M T = n 1 -1 01i ',L_ oiRiL-A - 4.7 kCI7:=::i CoI'9l-ID I TI_d R(_IRIC FF- C;LJE!-F" J (uTF. N r- - '2 77 E.{'2 W:4 _J'VI RLk ;f D FLOW 'v ALUln S C,t .1`, I__ W-_ 2 0 4 ^d 41 4 B - ,t]1=I [ir l`IF•II L r-!_OW V A L Ur- L - 1 C~7 7_ L 172 I; r) - . ~Ir.ltza I -D . 20r) CgriF-`LJ FF T) Ye L[JI-S I° UR = l zI . 1 Q I ICI 1 #-i-' 1 rJ~ - . lv M0N'C ~STA'T5 S NDFrtR AID IIoN IAa. 1L1 QRAIWA E C.A~..~L1LA~C~[ t s 9/2-9 /94 - BASIN - - - - - _ - - ~ow5-CR~~iC~ ~ t~3~ -~"C•3 it ~ ~o~~l.Ir ~A'~~=EI~ DRYw~I.[.5 ~3 cF~ ou-t) S~C 9 F~ AG}~ P C~DV ~l7 = Ar 4f 4 z z Z~ w2~ ~ ~5;;3l+t gyp! faZ - 3u.36-k- [~IDG~M~NT ~~TAYi ~S Nv~rtK ~T~t f'~'DFI~~o[d NQ , 12"~ I~ D~P•►r~AG~ C.ALCU LA7ivr4S Kw~ 2041 690 f1, 4,~ r~ it~ t'~a~Y, ~a0NvF,A._ST (.-~0.6. , (1(~~ .~.1.~9, F-T D.Z$ AcF-F- 7-0 1D T- ORR L~ T D I ~-53,4r is . . n sn . w . c r - r r.w-,.-.-a+vw a-w~..n..e...r.... ._,n~ . 1. . - _ _ Y r. • _ n . _ a: _ r.... - _ .n __n_.. .r _ . - -...--w .r,. r. _y.... -r~rr... _a ~qr « --e.v,•. rn....ew...w.. .................Y--._.~ -r-. _.r... _.a-._r.-. - _-s. _ a_. _a_... .r--n._ w. rwa.._-....a-..~_..-.>_._-r-~~.r.r ti _~-.._rre_~-w r>-._-_. __v_~.__.... r.r_r „•.r _..r_.«-f. . _ . . m. . r_r..... •-.w_- m~ ._~.m _ _ _ -li'r~_ . _ _ rr._ _ _._.v-..._ ._..r.._.,.~«. - .~_r-.,._~~r ~.....n.r..~.__. r - - BOWSTRING CALCULATIDNE LATE = 9/30/ 94 DES IGNER = V W MCMULKI N BASIN "C" PROJECT NAME = R.E. NORTH 6TH ADD. DESCR I PT T DN = STORMWATER DRAIN AGE t t Intensity Qdev. Vin VOUt Storage [min.) (eec.) (in. /hr.) (CU. +t.) (CU. ft.) (CLL. ft.) 5. 0 %iM Y w. 18 . 137 1557 300 1257 10.0 600 2.24 2.73 2194 600 1594 11.9 71 2. 04 2.48 2371 71: 165 7 15.0 900 1.77 2.16 2463 900 15063 220.4 1200 1.45 1.77 2546 12200 1348 - 25.0 1500 1.21 1.47 2=mr66 1.=.~00 1065 0.. 0 18022 Y 1. 04 1.27 2: 87 1 sOO 787 7.5.0 2100 .91 1.11 .I 11 2596 2100 496 40.0 2400 .82 1.00) 2639 2400 2:79 45,0 2700 .74 .90 226522 22700 -40 50. C; 3000 .68 . 6.? 22686 3000 14 55.0 3300 .64 .7S 227622 :71300 -571 8 60.0 3600 .61 .74 2855 7600 -745 65.0 3900 .60 .722 7.002 3900 -898 70. 0 4200 .5B .71 31.:2 4210[:5 - 1062 75.0 4504 .56 .68 -;206 4500 --1294 GO. 0 4600 .5-3- .65 :.255 4600 `1545 85.0 5100 .52 .67, 351 5100 -1749 90.0 5400 .50 .61 -436 5400 -1964 95.0 5700 .49 .60 X547 5700 °2153 1 CIO. 0 6000 .48 . 58 1,650 600Ca -2~ ICY THE MAXIMUM STORAGE IS 1657.10258599 CU. ET. The time o-f concentration is 11.8912:N mini tee. The Undeveloped flow out 15 1 c,f.s. TEN YEAR STORM CALL DATE = 9IZO/94 RATIONAL FORMULA HYDROLOGY DESIGNER = K W MCMULK 1 N BASIN "C" PROJECT NAME = R.E. NORTH 6TH ADD. DESCRIPTION = STORNWATER DRAINAGE SUBAREA 1 SUBAREA 2 TDTAL AREA OVERLAND F Ct L N S = .63 y ACRES = 4.34 ACRES 4.97 ACRES _OW VALUES .15 = 530 .4 - .021 CHAN114EL FLOW VALUES L = Q TD = 0 COMPUTED VALUES DUR = 1 1 . 59 I 10 = 2.X14 ryry q Li0 L. Am QA - C~ • 00 SUBAREA 1 RUNOFF COEFFICIENT = .9 SUBAREA 2 RUNOFF COEFFICIENT = .15 CCIi'' POS 1 TE RUNOFF COEFFICIENT = .245070422535 ~1DCa MDKrt eSTAT5S NDF--XR CoTH P,D'DITIDN Ns~. ~~~t~C• 0.) 2-0 5-TOP AG~ - _ PONS-TlzIt-l6 --.165 --~T.3 P 1u 1.9 ~AKFeL -9FYW I-.5. 5~ D Fz AGE ~~oV lptfl - - - - - - r 1r _ 3 0,3 SF ` ~ 90 3n.3~vk 7-5 DRF~tNAG CALCU A~tvr~5 .k [3v F~ A 5 IN -0. F f-.4 t T e L1 N "D a _V CL 0 _P. E- D ,FKV T 4R- C., R us RATIONAL FORMULA HYDROLOGY DATE = 10!7094 DESIGNER = K W MCMULKIN BASIN "B" PAVT. PROJECT NAME = R.E. NORTH 6TH ADD. DESCRIPTION = STORMWATER DRAINAGE SUBAREA 1 = .7.6 ACRES TOTAL AREA = .76 ACRES OVERLAND FLOW VALUES Ct = .1a L _ 0 N = .4 rs - . 01 CHANNEL FLOW VALUES L - 505) Z1 = .17? Z2 = =36 N _ .016 S - .015 TD .1586 COMPUTED VALUES DUR 5.00 110 = 3. 18 0110 - 1 . OC DA - 1.03 SUBAREA 1 RUNOFF COEFFICIENT = .9 COMPOSITE~RUNOFF COEFFICIENT = .9 L%,uxja.r- Flo,4) co&~'s CU~~ QFI NINE AT L.'4W ?DINT , STA. 311-98.18 S" = 0.41, -~vdal l(r &L 561- o' ❑?eV%j"3 l~ w 0,1556, L7ep~ln of waxier aA e-vptrav+ce ( Y 1,03 CF5 oiol beak ra~~~ p~ ~iow I 3j GL 2- 3 0'8 -1 ~A OJS66 h to 0.61 r 0~f2 i 1 ' riowsTRI NG i C3^II__CUL..AT I LI1,JS D SF -;NER I•' Eel r'ICN',llJI_F°I N D lSI N "E;" F'IROJECT NAME = R.E. I,10'r3TH 6TH ADD. D SCR I F'T T ON mm STORM WA TER DRA I NAOE L III I"Er4SIty Od a v. V I n yoI_It St nrage (III Lli.) Lw.f tie. } 0 n. 1hr-. 3 (r. 3 =a. )I ((--U. 4 F.. ~ WLL. $"1-. ~ Li Ll. f t. ~ S.") T e:{p]C) 1. 3 8 4.. 07 1676 60o 10711 a C1 600 7. 2- 4 2.07 2012 1200 812 15. Cl 90C) 1 . f 7 r'. 26 22)9 1Cli0 (_1 469 e{.a . C] y t_}k l 1 M 215 1 . 86 2 41 b :'_=i 1 16 2_5 . o, 15 0 ] ] .2 1 1 . 515 '2400 70f-]i_1 -..~z-i } TIC]. 0 lo0o 1.414 1 . - - 2,b 1 ~:~,[]C3 --1069 -71 J Cl 21 100 .91 c; '75 o64 4200 -l rte. 6 40. 0 '~j no .92 1 , ta`, ~6','t. 4C3( _1 ] --2175 45. CJ 27,n0 .74 w 9 '265 ee 1 C) C-) -27-47 5) C] . Cl 7000 . „c-3 .87 269Q 6000 --31 01 54 . 3'2 "796 66CIC1 -•7nI3 ca C1® o 1 CI0 .61 . 713 2009 72C]F ] Lb-31 1 f f.} . ?00 . 6C) .76 :~C14 r 7c3CIC1 ~4 75-i 70 C} 4200 .58 .7z3 39 5400 -5207 Ci .]k.} ~6 . 71 y6; }ClC-) 0 °.r f'2 PC) ca . r . 613 _ . rE 9600 -6276, 95. C ] 5100 . 52 .66 :ill -4:x'6 1 C)2100 -677 1701.0 ~4C1O .50 .64 ~5 -'C1 10800 -7" 80 V t2i . 0 5700 .49 .6-- 76 ,8 1 140C) -7762 l;el~t. (I 6 1t')C] .4A .63 ;11,7110 1 ,C)(,)0 --a:' THE MAXIMUM STORAGE IS 1C1 ;5.6616' CU„ F=T. 4, The, to rmca of c-onc-I*rltrati n i s 5 monUtOS. 11-im, [_Inuego] apis~[1 r•'1 73 LIa L,aL.It . C 2 c. d . TEN YEAR 1,33TOR'M CAL(- t,,' 'II/ i;,A-ri CNAl.. FORMULA H ~'I)!;[_ll_{=1C~`r DATE = ?/2//94 DESIGNER = F: W 3MC>1` ULi:IN BASIN "F{" F'R'O-J EC T NAME ~ IR . i° . NORTH' &TI-i ADD. DESCRIPTION I~TORHI,,ATER DRAINAGE SUBAREA `1 = 1. 0? c i:EIs SI.IBA R =A 1 F,C.INUF F" C 0 F"F I C f i 1\1T = K 9 ~IJDs'yi Ef7 = y?. 3, l ~yl R. C~CJI,; -~F2E ~1 RU R4Ji~EC1F'F C DEF-F I C I E N'r = 1 -i-o-fA ii- AREA e. IS A C RE C:OMi OIS1` E iiUn1t]l°°1'= COE FICTrNT - .4 2=4849566 d O','ER'L.C)ND FLOW VALUES L = Cf 99 ;:i , r 7 1 L`FiF <i NE L FLOW VALUCS CM CJ 1 a Z 1 .17'2 Z 2 -:6 tN - .tt16 D 0 S - .{)!2 r,rlf F'IJ I ED YAL LIIT;S DUR 5„ 00 1210 - -q OA ~l , 11-11 E ~DGENIaMT ~S-TATES NDRTK 6TH KDlATroN 12.1D6 d A~~AG~ ~AL~u~~.roo~ts ~IZ9/94 Kw ~~SrrJ B k2 4N. fir)- SD Wa L E . F.F E.L ~ P-.Y-w-r k. tr y (z c vu~[ -3 1D. G 1 r rsG, + Z`3 '4 _2 5 2 6D 2 F-I©GEMON'T aSTRTIS No~LTI'-k 6" A£~b1~~vn1 Na. -11 (1 I VN M 1A f AC'Fs✓ lk ~r~P 5 - 1 ~ 1 -l-. ~,74j ODD 000 -.-r v~ou r~ - - - - •_~-~,~~ss -z-- ~~BtS~~_- ~t~,~_i~.._ _ r..9.1r X34_ - . '2,1.1 .,Pc1~'~ I Table 5 --,Runoff curve numbers for selected agricultural, suburban, and urban land use. (Antecedent moisture condition Ii, and I. = ❑.2S) HYDROLOGIC SOIL GROUP LAID USE OESCR.1MON A R C i) Cultivated 1and=1: without conservation treaeacat 72 81 88 91 with ;onservation treatment 62 71 78 81 Pasture or range land: poor condition 68 79 86 89 goad condition Q 39 61 74 80 Meadow: good condition 30 5°8 71 78 W-4 or Forest land: thin stand, poor cover, no mulcts 45 66, 77 83 good cover+l 25 55 7O 77 Open Spacea, lama, par"@ golf courses, camotarics, etc. 6044 conditioq: grass cover au 75% or more of the area 39 61 74 80 fair coaditiga: grass cover an 50% to 75%,of the area 49 S9 79 84 C- rcial and bualnesa areas (85S impervious) 89 92 94 95 Iadustrisl districts (72% Impervious). 81 88 91 93 Resideatia;:lf Average lot site Average Impervious." 118 acra or lass 65 T7 85 9o 92 114 acre 3d 61 75 83 87 113 acre 30 57 72 81 86 112 acre 25 II 54 70 80 85 1 acre 20 51 68 79 84 Paved parking lots, roars, driveways, etc,-1 98 (-9,B-) 98 98 $treats and roads pared with curbs and storm saverell 98 98 98 98 gravel 76 85 89 91 dirt 72 82 97 89 ll For a more detailed description of agricultural land use curve numbers refer to Aatioaal Engineering Handbook, Section 4, Hydrology, Chapter 9, Aug, 1972, !1 Good cover is protected from grating and litter snd brush cover Boil. 31 Curve numbers are computed assuming the runoff from the house and driveway is dir"ted torarda the street with a minimum of roof water dtrectad to lama where additional Infiltration cuuld occur. -1 The remaining pervious arena (lawn) are considered to be In good ,Feature condition for these curve numbers. 21 In some warmer climatca of the country a curve number of 4)5 may be used. TABLE 5 z i i z ~tf DGEmowr E STAI9F ' BASIN DESIGNATION R vut-r~ vrFfsj-re PROJECT Nog- H CTH AVpLTiaN CALC-k.W. MCKuLr-rN DATE 1,0/3/9+ CHECK DATE SOIL GROUP AREA 11.9+ (Acres) SLOPE % CURVE NUMBERc PRESENT CONDITION FUTURE CONDITION LAND USE % CR i PRODUCT GF~~55 2..`$a WEIGHTED CN: ~I I.4`6 ~ i RUNOFF DEPTH: . 2 in. Qi in. P1 7. o in.,! QI[__ in. P50- _ In. Q5 in. Ploo_ In. QIQO._ in. PEAK DISCHARGE:, HYDRAULIC LENGTH Q ft. EQUIV. AREA Acres EQUIV. x SLOPE _ ADJ. EQUIV. PEAK CHART PEAK DISCHARGE FACTOR _ DISCHARGE FLAT (0-2%) cfs/in. MODERATE (3%-7%) cfs/in. X cfs/in. STEEP ()8%} cfs/in. ADJ. EQUIV. PEAK DISCHARGE X ACTUAL AREA g ADJ. PEAK DISCHARGE EQUIV. AREA cfs/in. X Acres = cfs/in. Acres ADJ. PEAK DISCHARGE cfs/in. X ( ~ Q (in.) = DES'xGN DISCHARGE cfs/in. X QZ in. = D cfs. QI in. 01 cfs. Q, in. D5 cfs. QIO in. 3 14CL cfs. I FIGURE 14 6-I5 Quick TR-55 Ver.5.45 S/N:1315460151 Executed: 11:22:08 10-03-1994 Ridgemont Estates Korth 6th Addition RUNOFF CURVE NUMBER DATA Composite Area: Ssain A AREA CN SURFACE DESCRIPTION (acres) pant./roofs/drives --..-0-a5 -98 V grass r P044v".rt 11.09 +11 69 Lool COMPOSITE AREA 11.94 71.1 [ 71 Quick TR-55 Ver.5.45 S/N:1315460151 Executed: 11:49:34 10-03-1994 REN6TH-TrT Ridgemont Estates North 6th Addition Tc COMPUTATIONS FOR: Basin A SHEET FLOW (Applicable to Tc only) Segment ID Surface description Manning's roughness eoeff., n 0.4000 Flow length, L (total c or = 300) ft 0.0 Two-yr 24-hr rainfall, P2 in 4.000 Land slope, s ft/ft 0.0000 0.8 .007 * (n*L) T = hrs 0.00 = 0.00 0.5 0.4 P2 * S SHALLOW CONCENTRATED FLOW Segment ID grass Surface (paved or unpaved)? Unpaved Flow length, L ft 800.0 Watercourse slope, s ft/ft 0.0190 0.5 Avg.V = Csf * (s) ft/s 2.2240 where: Unpaved Csf = 16.1345 Paved Csf = 20.3282 T = L / (3600*V) hri 0.10 = 0.10 CHANNEL FLOW Segment ID Cross Sectional Flow Area, a sq.ft 0.00 Wetted perimeter, Pw ft 0.00 Hydraulic radius, r = a/Pw ft 0.000 Channel slope, s ft/ft 0.0000 Nanning's roughness coeff., n 0.0000 2/3 1/2 1.49 * r * s V = ----------------a---- ft/s 0.0000 n Flow length, L ft~ 0 T = L / (3600*V) hrs 0.00 - 0.00 i ..TOTAL •TIME .(hrs) .....0.10.. Quick TR-55 Version: 5.45 S/N: 1315460151 Page 5 Return Frequency: 10 years TR-55 TABULAR RYDRdGRAPH METHOD Type II. Distribution (24 hr. Duration Storm) Executed: Watershed file: REN6TH .MOP Hydrograph file: .HYD Ridgemont Estates North 6th Addition Time Flow Time Flow (hrs) (cfs) (hrs) (cfs) 18.6 0 22.4 0 18.7 0 22.5 0 18.8 0 22.6 ❑ 18.9 0 22.7 0 19.0 0 22.8 0 19.1 0 22.9 0 19.2 0 23.0 0 19.3 0 23.1 0 19.4 0 23.2 0 19.5 0 23.3 0 19.6 4 23.4 0 19.7 0 23.5 0 19.8 0 23.6 0 19.9 0 23.7 0 20.0 0 X23.8 0 20.1 0 23.9 0 20.2 0 24.0 0 20.3 0 24.1 0 20.4 0 24.2 0 20.5 0 24.3 0 20.6 0 24.4 0 24.7 0 24.5 0 20.8 0 24.6 0 20.9 0 24.7 0 21.0 0 24.8 0 21.1 0 24.9 0 21.2 0 25.0 0 21.3 0 25.1 0 21.4 0 25.2 4 21.5 0 25.3 0 21.6 0 25.4 0 21.7 0 25.5 0 21.8 0 25.6 0 21.9 0 25.7 0 22.0 0 25.8 0 22.1 0 25.9 0 22.2 0 22.3 0 Quick TR-55 Version: 5.45 SIN: 1315460151 1 page 4 Return Frequency: 10 years TR-55 TABULAR HYDROGRAPH METHOD Type II. Distribution (24 hr. Duration Storm) Executed: Watershed Pile: --a REN6TH MOP Hydrograph Pile: .HYD Ridgemont Estates North 6th Addition Time F1oW Time Flow (hrs)--`- ---(cfs) (hrs) (cfs) 11.0 0 14.8 0 11.1 0 14.9 0 11.2 0 15.0 0 11.3 0 15.1 0 11.4 0 15.2 0 11.5 0 15.3 0 11.6 0 15.4 0 11.7 0 15.5 0 11.8 0 15.6 0 11.9 0 15.7 0 12.0 1 15.8 0 12.1 4 15.9 0 12.2 2 16.0 0 12.3 1 16.1 0 12.4 1 d 16.2 0 12.5 1 16.3 0 12.6 1 16.4 0 12.7 1 16.5 0 12.8 1 16.6 0 12.9 0 16.7 0 13.0 0 16.8 0 13.1 0 16.9 0 13.2 0 17.0 0 13.3 0 17.1 0 13.4 0 17.2 0 13.5 0 17.3 0 13.6 0 J 17.4 0 13.7 0 17.5 0 13.8 0 17.6 0 13.9 0 17.7 0 14.0 0 ° 17.8 0 14.1 0 17.9 0 14.2 0 18.0 0 14.3 0 18.1 0 14.4 0 18.2 0 14.5 0 18.3 0 14.6 0 18.4 0 14.7 0 18.5 0 Quick TR-55 Version: 5.45 SIN: 1315460151 Page 3 Return Frequency: 10 years TR-55 TABULAR HYDROGRAPH METHOD Type 1I. Distribution (24 hr. Duration Storm) Executed: Watershed file: REN6TH .MOP Hydrograph file: HYD Ridgemont Estates North 6th Addition Composite Hydrograph Summary (cfs) Subarea 11.0 11.3 11.6 11.9 12.0 12.1 12.2 12.3 12.4 Description hr hr hr hr hr hr hr hr hr Basin A 0 0 0 0 I 1 4 2 1 1 Total (cfs) 0 0 0 0 1 4 2 1 1 Subarea 12.5 12.6 12.7 12.8 13.0 13.2 13.4 13.6 13.8 Description hr hr hr hr hr hr hr hr hr Basin A 1 1 1 1 0 ❑ 0 0 0 Total (cfs) I 1 1 1 0 0 0 0 0 Subarea 14.0 14.3 14.6 - 15.0 15.5 16.0 16.5 17.0 17.5 Description hr hr hr hr hr hr hr hr hr Basin A 0 0 0 , 0 0 0 0 0 0 Total (cfs) 0 0 0 0 0 0 0 0 0 Subarea 18.0 19.0 20.0 22.0 26.0 Description hr hr hr hr hr Basin A - 0 - 0 0 0 0 Total ( cfs ) 0 0 0 - 0 0 Quick TR-55 Version: 5.45 SIN: 1315460151 Page 2 Return Frequency: 10 years TR-55 TABULAR HYDROGRAPH METHOD Type 11. Distribution (24 hr. Duration Storm) Executed: Watershed file: REN6TH MOP Hydrograph file: HYD Ridgemont Estates North,6th addition 5>» Summary of Subarea Times to Peak <<<< Subarea Basin A Composite Watershed Peak Discharge at Composite Outfall (cfs) 4 4 Time to Peak at Composite Outfall (hrs) 12.1 12.1 Quick TR-55 Version: 5.45 SIN: 1315460151 Page 1 Return Frequency: 10 years TR-55 TABULAR HYDROGRAPH METHOD Type II. Distribution (24 hr. Duration Storm) Executed: Watershed file: --7 REN6TH MOP Hydrograph f i l e : . HYD Ridgemont Estates North 6th Addition Input Parameters Used to Compute Hydrograph sccc -Subarea AREA CN Tc * Tt Precip. Runoff Ia/p Description (acres) (hrs) (hips) (in) I (in) input/used Basin A 11.90' 71.0 0.10 0.04 2.00 61.1I 0.27 1.41 .41 * Travel time from subarea outfall to composite watershed outfall point. I Subarea where user specified interpolation between Ia/p tables. Total area = 11.94 acres or 0.01866 sq.mi Peak discharge = 4 cfs -j 0 Computer Modifications of Input Parameters <<<cr Input Values Rounded Values Ia/p Subarea Tc * Tt Tc *"Tt Interpolated Ia/p Description (hr) (hr) (hr) (hr) (Yes/No) Messages 3asin A 0.10 0.00 Yes - * Travel time from subar ea outfall to composite watershed outfall point. ti* Tc & Tt are available in the hydrograph table s. D6J, fog POND-2 Version: 5.15 SIN: 1295160123 Plotted: 10-03-1994 11.3 11.4 - 11.5 - 11.6 11.7 - 11.8 11.9 - 12.0 - 12.1 - 12.2 - 12.3 - 12.4 - 12.5 - 12.6 - 12.7 - 12.8 - 12.9 - 13.0 - 13.1 - 13.2 - 13.3 - 13.4 TIP (hi * Fj x FJ ,I Flow (cfs) 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 x x x x 1E 7S) .le: REN6TH . HYD .1e: EST-f?oMTE. EST x x Qmax = Qmax = q 4.0 cfs 2.0 cfs POND-2 version: 5.15 SIN: 1295150123 OUTFLOW HYDROGRAPH ESTIMATOR [<[[C Inflow Hydrograph: RENOTH HYD Qpeak = 4.0 cfs Estimated Outflow: ESTIMATE.EST Qpeak = 2.0 cfs Approximate Storage Volume (computed from t= 11.90 to 22.20 hrs) 900 cubic-ft p G t~-1 ~r N~c S A°t s K O F.I " p 1 T +v N t~l o• t L R►~it~AG~C GALCU ►~-rsoIk s KWM ST pRAGE REQ l51 Rib • , - - - - - - - - - - o.~ "2~~~ _S_SD'~F•G~__~.~~22iv2~,~T~}~ ~z~ ice' T~ .R _F'C~~_'~- 12+N• IFZ• Aau .P9Y_W-.~~-GF ~STItAPIT 10F_ 5To~P.G6 PRIDy MSID Qo- Ve, - ' t ?o tA ?-vD66 ORI ~5~~~~5 ~RrtH ~rt~ ~,D~at--ti~rv Ida 1. tz'1tC, [~RAINRCti~ G1~, L~l1LAT dvNS ~ ~~b~9'~ k trr! M - 13As tN A - - - - - - - - - - - - - ANa._- or LvTS_ e 151 oC) o F-[ - p ~1V ~ 5 L 4~ _ GRAS ~ - A(. Soo 149 Ak or -04- Avg f Stormwater Drainage Report; Ridgemont Estates North 6th Addition SUMMARY: The development is divided into three (3) basins; A, 8, and c. See Drainage Map for Ridgemont Estates North 6th Addition. Each basin is composed of two subareas; 1) grass lawns,{and 2) impervious roofs, driveways, and asphalt paved streets. St;ormwater flows overland across roofs, grass lawns, and driveways and into grass drainage ponds. Stormwater from asphalt streets flows alo'~tag the curb gutters and into the grass drainage ponds through curb openings located at low points in the curb profile. The present drainage basin boundary for Basin A is shown on the drainage map. This basin area will change as adjacent unplatted port-ions _of Ridgemont :states North are platted. aka,- r- caf asin i1, sma ler in t~fe 1=uLure bu m-erv-ous sub ea w' _ 7cf°e se. T ~ d'e i n ane sc FAI~iG'es wil- e c~e~'gneci Far he pre -runrcf r 1c~n ra l~r._ r h i he to u e c, m nn. ne Ira) nag c' lities will be constructed outside this plat, and modifications to the pond can be made later as adjacent property is developed. The drainage basin boundary for (Basin c will change slightly as adjacent portions of Ridgemont Estates North are platted. The basin area will remain ,about the sarne size, but the impervious subarea will incr ease. Calculations for stormwater runoff were made for a present basin condition and a future condition. Th jif e LI rur~e3fiJ~tarn,l.CTTr;~B 1~ - l mod, rags a rlar~e~tr,►' vie 1w a'nd~tara9e an h`~s t • ~ . Th eifrTrG-T,= i•a~r r„a-e detent'on and d's he F 1 •n1~rgm -ra - S t,rte.•etwl le der- -fined f a he fir to re runcaf f c - nd • n ce oi0~1y~liCclrftx~ClliiT~'kh]'a "111E~PJsi-n1Ida&i.w~~~r 41f~aC~e ` 'CW] Cl ure The grass percolation areas (drainage ponds) were calculated to hold the, -first 1/2" of rainfall runoff over the asphalt street areas. Figure 2, page 6-3, of the "Guidelines for Stormwater Management", by Spokane County Engineers, was used for rainfall intensity and duration occurring at a, C~-y ar s ~a-- f rroc. luer oy. The Rational and Bowstring (Methods were used to calculate the peak stormwater runoff for each basin, and the'type and number of drywells needed for each basin based on the storage capacity of the pond. I , STORMWATER DRAINAGE CALCt1LATIONS FOR RIDGEMONT ESTATES NORTH 6TH ADDITION October 12, 1994 a t-66iC` ~ 50, 7 I' u►a" S Prepared by: ev- Simpson Engineers, I6c. North-909 Argonne Road Spokane, Washington 99212 TABLE OF CONTENTS I. Summary II. Stormwater Drainage: Calculations for Basins A, B, and C of Ridgemont Estates North 6th Addition] III. Attachments-► Soils Map and Tables ;I w- Street and Drainage Flans. 7'F ova. McM~ WAS OFFECiA!- "II LI DOCU%.-~-::T SPOKANE C01UN1 T Y ENGINEERS OFFICE -drys 0~ ~AL PROJECT I r RECEIVED I;p '~2857$ ~a SLIIjM17AL = c'` 'O CT 13 IM AL~ . RETURN TO COUNTY ENGINEER 4 } DATE TQl4/ • - SPOI[A{~E COUNTY ENGINEER - Exhibit A-1, continued: Hydrologic soil groups for United States soils F:EcsI C ( fVLSNE•A C I GAPC01 D I GLD FCCSTONC C ( FYLSTONE C I G♦PC 0 1 GILISPIE 0 rALe IOVN • 0 1 ELL ION 0 1 G•PO. ORAINCO D C I GC( I GtCOUWG C I GILL•N0 C rRCer♦T(R 11 1 /uL is 0 1 GAPPNA TEN 0 1 GCLNORC C I GILLCNOLR 0 fAELLC r l fYLr10CR O 1 GAR* L 1 G1LL1•w c CU T , • U E b l fun lLA 0 1 F APFCR C 1 6C9 61 0 1 G14L1G•N p U04 O FN LLStluRG 0 1 fuOUAt . b l Cefalstm 0 1 CILLS E NONT C I fuRNISS cawro O Ct 1 • 1 GILL30uPG C p WL N 0 1 fuNaNYA 0 0 ( G1PrUTT G IS 6 1 b G Lw•N I l p f0c«CN C 1 (WWI 1 4A CENO C C I G949 C I L wOW[ 1 G OOR C Af rC NC AEfR 0 •I fuQv. Ov•INCD 0 C 1 r, ANCtS ( GAACI• G C 14fLAlf b l GIL p FgE MChJCNN C I An ULINA C I GARCIIAS C 1 Gem I GEN $TON► C I G{LPI« C fA ENC nw A N O I fuluvAf. C 1 G.PCON C . 1 LLw10 / C C iR rN O I G•ASIA• C I GARCCLIp 0 1 GLNSON C 1 41La ON LSe&f R N n.LA 0 1 C►OAL]UN 0 1 6fRCLNA r l 69NAr .tl I GILT LOLL C 0 F E FRESNO. 0 G♦665 C 6ANOINEP • GCNtGR•f 0 GI-Lfl 1 1 0 1 GA00VALLT D HICK I GfPDNtAtS fOGK li l GtwtSL! p ET FRESNO. O O C 1 GAO CI C 1 GARONERC 11-6C C I GfNeV• t O I G11.t• G GL 0 W w S LUI- S 1 GAb ICA D GIAD ON! I 1 Gtho• 1 IN A 0 fWfr• fAE [NIK 0 0 1 6.pINo D 1 GAWtT r 14ENOLA D 6 I GINI 1 GINLAND o O Fgl•w• D 1 GACET 1 GACINAOD C I GAaI•N C I G9N11lLT D 1 41Nw10 C #'AI••rl D I GiC1tl, O G•AfltLn I C I CCNTAV 0 1 GINSFA C ►A I OLO C l G•OOCS 0 C 1 GAMN ILL 0 1 6&000«0• C I GIA.RD O 1LOL•NOEq C 1 6.001 I GAalpe" C 1 GCLNADCK o f GIAA400T p 0 0 FA If O.•N C 14.OSOfN A 14AA11• E 1 6COAG(CAELK O 1 GIRO p IAIENOS C 1 6 . VL T C C 1 600LA«D R 14 n I GCOWGCtOVN 0 1 GIST D rA1~NOSNIP ♦ W05 fR I aub AT uw Ltt 4 I G1dLOCL C I GtORGfVILLE 0 1 GII•KYD C FRIES - ] GAO-!LL. C I GAhNPN O I GtORGI• C I G11•w 0 falzsLANO 4 I G•GLOr b AR«DPf I C I U I GLPfcao Gf PO C 1 GIrIN C •LIJCLES IS I L•GtlO•% GIANeL 0 I LL •C IfACA[LK FgiNOLE C C&4 1L' C 1 GtPPEAT C I GL•OOCA 0 FAI«(S C 1 G•..EL , • I G1NN[W O 1 GERALD 0 1 4LACtL D iW10 t I GARNIL t I Gcorta D 1 CA.AOCVILLC 0 fAloA♦ C 14•IL• D 141MD 0 1 GLPOWUN 0 1 GL.OLr. Ica - p FQI) to.. G 1 G•1NES b C l GAWA D I GtLING 0 1 GLAOSTCNt 0 IRIPP C•1NtSOCgO I C ( G.GNEiSOv V 1 GLRLACN fa IScD b , I GAII.LSrILLC A I F•ARat11 I I 4•gg157 CARL •wf 0 1 4L•aG0■ C iglSllf 0 1 G.L•1• p N l C.AppCNS t 1 0 GLWL! 0 1 GL•SS«LA G FLITI 0 1 G aa. nWEiN ] c 1 GfWwANiOrN o f 4L:•N p PAI[[fLl C 1 4♦6CNutt C •N'10 1 P f l GIYw•AT r l 4LE•a0A 0 FWOOEP(. O ( -6i 1 GA TCN C' I GfgwEfi C I GLEEC C iW000 ] I G 6fN 0 1 OA - C 1 6tWON1 C 1 4LFN p N t &R I G•Av IN P 1 GtKR•R fMOL IC I I CALL SI IA• C C l 4 n/01 G(WA♦RO. DAAINEO t I GLFMp•P. it C ;COLIC. C I G•Lt;/qrw • 14..961[. A 1 GA6jPt.• r l 6tWal 0 1 GLENOCAG b rLLV•TION<5000 14•LfT o f G•S CLLLK D 1 G(SSIE t I GLLNbL♦lA C %OOLIC. FL000f0 f, 1 GALILEE c 1 CASCCN•0• G 1 GC%SNfR r/01 GLThpROOK p FAONnoAf o I 4.1. ISIfO C 6•SIL 1 n l CtsIPIr A I GL•«C•Mn t FPONItN.C 1 GAL. ISI(0. C , 1 :.A SG LIT r l 4fTAr41 0 I CLENCARD• VL1. C f]ON11LW C I SAL IN:-•LKALI ( GASSAV•T I D Gt1CNELL C 1 S•LINt ;~~lo. G 1 .:.LL•w t 1 4.savlLLe 1 C CIICAIL D 1 GLCNCOf 6'0 Fq'ST ] I :..LL•IIN C , 14 A% 1D11 I C eflrTS C 1 4LfNCn(. PONOLO 0 f aozago C I G•LLE405 e , I GAT I • Gtl[VILLC 0 1 GLLNOALE p FMUIT• n 1 G•LLfN 0 1 4-Its 1 GtrieK C 1 4LLN0•L(. ALT C FAU11`►I1LO . 1 CALL I• I I GA1(SCh r 1 C GtVSLN C( GLCNOALI,. R•AELT C tMuIINY461 C 1 GALL1+! 0 1 CAIt TILT I 0 G100LfR C 1 /LOOOtO f PU1TU NU ! I WLLION b l GAIf►'T 1 GIUVON n 1 GLENOIRSON p if.u1TLAN0. C I,4.L LNArI tl 1'GAlfrroC C 1 61000ASCALEK C( CLANG Irf p NcO:RAItLr OL1 1 G.LLUP t l GAIL at. C I Gloos D 1 GLL«oOW• A,0 fAUITLANO. wo C 16.4.00 CIO I CA IOW D l eltNer C I GLf«tOLN p EAT( C 16.4.1 AT;(: U 1 G10SOVVIL6e 0 1 4LIN(LG p favesuR4 0 1 4.LY4 f 1 G C I GIOrCLL C I GLLNiOAO C fl. opur C 1 C. •LVC51vd. • 1 G•YL `t I C C GIOLO C I GLE«N•4. L Ft. 4D4L« 3 1 L.L r;t C I G~r(L I . ItLD G C I GLt N..•w n Fuo•0 C 4.6vift 0 1 6AVILAN C I GIFFORD 0 1 GLf N- •v p fYHLL 0 I GAT.t 0 1 GAVINS C 1 GIGGeR C 1 GLL«• C t utG] C I G.+CLLA 0 I GAVIP14 O I GILA 0 1 4LLN►._~Gw C fuCGOST• 0, I 4"004 0• GAV I D 1 41LOCR1 U I GLLNOwA p f ut RA C I G4016Ce C 14ArLtSrILLS O/01 G1L00A 0 1 4LewPOOL •~G•rff A I c•NADO o f 6.1LUAO 0 1 CILOT o 1 LLEwW10 p fuGNtS C I G.wC! C I Gr T N C4 C C I 116, .W IS1 • I GLLNAOSt p LCN(A C 14•«00 0 GA 1 I I I L C O o 1 GLINWOSS p FU LOA e/o c l •N1s 0 LI , 9 ( GAIt LLL 0 1 G1LCAf ST 0 I K EMSICO p f YLL•+ C G.Ni.E T T O . GALO S I 0 1 G1Le.p C ( 4L to. ION 0 /uLL:r 0 I L•NaNfq ' C ( GAIVfLL C I GIL(S n I CLINTON. r(t C fuLLERION n l G•NSNtA. PONOCC O I GLAFNAur C 1 41LfOWO n/pI 1LtN1oSN FuLNEP b I G(.RT A I GIL/CRD. D I GLCMVILe p OWLNra. OAAINCO C 1 G♦P OUT Tf • n 1 6t11pGM b ( STWA11f IL0 I GLLNV ILLS C n 1 wbsTNAluw I cLtwroM i~ Appendix A: Hydrologic soil Soils are classified into hydrologic soil groups (HSG's) to indicate the rri1111mum rate of infiltration obtained for bare soil after prolonged wetting. The HSC's, which are A, 13, C, and D. are one element used in determining runoff curve numbers (see chapter For the convenience of TR-55 users, exhibit A-1 lists the HSG classification of United States soils. The infiltration rate is the rate at which %%.ater enters the soil at the soil surface. It is controlled by surface conditions. HSG also indicates the transmission rate-the rate at which the water move: within the soil. This rate is controlled by the suil profile. AplAroximate numerical rMiges for transmission rates sho%m in the HSG definitions were first published by Musgrave (USDA 1955). The four groups are defined by SCS soil scientists as (allows: Group A soils have low runoff potential and high infiltration rates even when thoroughly wetted. They consist chiefly of deep. well to excessively drained sands or gravels and have a high rate of water transmission (greater than 0.30 in/hr). Group $ soils have moderate infiltration rates when thoroughly wetted and consist chiefly of moderately deep to deep, moderately well to well drained soils t+,ith moderately fine to moderately coarse textures. These soils have a moderate rate of Mater transmission (0.15.0.30 in/hr). Group C soils have low infiltration rates when thoroughly wetted and consist chiefly of soils with a laver that impedes downward movement of water and soils with moderately fine to fine texture. These sods have a low rate of water transmission (0.05-4.15 irilhr). Group D soils have high runoff potential. They have very low infiltration rates when thoroughly wetted and consist chiefly of clay soils with a high swelling potential, soils with a permanent high water table, Soils W`Kh a claypan or clay layer at or near the surface. and shallow soils over nearly impervious material. These soils have a very lu%v rate of water transmission (0.0.05 h0u•). groups 1 In exhibit A-1, some of the listed soils have an added modifier; for example, "Abrazo, gravelly." This refers to a gravelly phase of the Abraza series that is found in SCS soil map legends. Disturbed soil profiles Asa result of urbanization, the soil profile may be considerably altered and the listed group classification may no longer apply. In these circumstances, use the following to determine .HSG according to the texture of the new surface Soil, provided that significant compaction has not occurred (Brakensiek and fir: wls 19133). HSG Soil lextnres A Sand, loamy sand, or sandy loam B Silt loam or loam C Sandy clay loam D Clay loam, silt3, clay loam. Sandy clay, silty clay., or clay Drainage and group D soils Sume soils in the liar are in group 17 because of a high water table that creates a drainage problem. Once these soils are effectively drained, they are placed in a different group. For example, Ackerman soil is classified as JVD. This indicates that the drained Ackerman Soil ss in group A and the undraancd soil is in group D. (210•VI-TIC.-55, Second Ed., June 1986) I A-1 V SPOKA &E CouN ry lsopluvia/$ of Id year 24 hour precipitation in lenths ❑f an inch. 20 IB 1 I i i i 26 26 2s Doer Park 26 2$ 22 ,SP©KANE I~Cz~MQN'f I.$TRTES NoR'fH 67H ADD. d ' I i I I 0 Ch9ne~ Spangle 20 Lalah 6-6 I ' 1 . s Fl GURE 4 Sheet ! ❑f 2 SPOKANE COUNTY Isopluvials of 50 year 24 hour precipitation in tenths of an inch. a ' 24 26 28 30 Deer 34 Park ■ 38 34 3d MSPbKANE tA[797" kDD. 22 28 GCheney !S angle Latch • 22 Z4 25 ~I IM FIGURE 4 n Sheet 2 of 2 b- 7 RATIONAL FORMULA HYDROLOGY DATE = 10/7/94 DESIGNER = K W MCMULKIN BASIN "B" PAVT. PROJECT NAME = R.E. NORTH 6TH ADD. DESCRIPTION = STORMWATER DRAINAGE SUBAREA 1 = . =.6 ACRES SUBAREA 1 RUNOFF COEFFICIENT = .9 TOTAL AREA = .76 ACRES COMPOSITE RUNOFF COEFFICIENT . 9 OVERLAND FLOW VALUES Ct = .15 L = 0 N - .4 5 - . 01 CHANNEL FLOW VALUES L - 505 Z1 = .172 7 L? ,6 N - .016 ~ C) 3 _ Ole TD = . 1566 COMPUTED VALUES DUR = 5.00 110 = :;.Is O1O - 1.03 DA - 1 .07 Cirlrr$ DF'~hYi~~ AT L❑VJ [}aINT .ETA, ~~-~q$."~~ [1~~5~t o'i D~~ininc~ = D,158~~ ~7e~~1n of wv~~er a$ e~.~rcz+~Ce r t-03 CF5 `~ot~l beak ra~~ oJ flow 3v Q z- 3.ra ❑r H 1 H_ b.LSBG, _ O.Z c l % 3.057 ~D•158~ Pz. C u [L$ ID w VA ~ r \,41 e ¢j ~ K1 L' E. ~ C~ID~~NIPN~f ES'rAZIF. 5 N 0gi14 67H FL?L7. Wo - 12116 Ra~N►aC~ CALcuL A"[ tv N5 113011+ ~A 5 P N C aYN _ D F~F5 El E, uN'D c- v-PEA - A_ pAv ,T; ~.~..606-} ( Lb') z---- l D,?-'l.i B._ g I D C~ E M O WT S T AT r; S ICI D 9.1 H Y H f'•D 17 lT l to tr . 1~-~ l 6 ~ pR+fy1NAG~ CAIr.G+~LF~'C~D~~ ~ ~q4 $As I N C. , 1N41 ~ 1 cFc ou~[~ CIO' SIB' 6 13 DATE = 9/_0/94 RATIONAL FORMULA HYDROLOGY DESIGNER = K W MCMVLKIN PROJECT NAME - R.E. NORTH 6TH ADD. DESCRIPTION - STORMWATER DRAINAGE SUBAREA 1 = .6e ACRES SUBAREA C = 4.i4 ACRES TOTAL AREA = 4,97 ACRES OVERLAND FLOW VALUES Ct = .15 L = 530 N - .4 S - .0'21 CHANNEL FLOW VALUES L = 0 TD = 0 COMPUTED VALUES DUFF = 11.89 Ilo = .04 010 ~ 44 E3 RA = x.00 BASIN k'C" SUBAREA 1 RUNOFF COEFFICIENT = . ? SUBAREA 2 RUNOFF COEFFICIENT = .15) COMPOSITE RUNOFF COEFFICIENT = .24,5070422-:535 BOWSTRING CALCULATION DATE = 9/30/ 94 DES IGNER = K W MCMULKIN BASIN "C" PROJECT NAME = R.E. NORTH 6TH ADD. DESCRIPTION = STORMWATER DRAIN AGE t t Intensity Qdev. Vin Vout Storage (min.) (sec.) (in./hr.) (c.f.s..) (cu. ft.) (cu. ft.) (cu. ft.) 5.0 300 3.18 3.G7 1 557 300 1 257 10.0 600 2.24 2.73 2194 600 1594 11.9 ►K 713 2.04 2.48 2371 713 1657 15.0 900 1.77 2.16 2460 900 1563 20.0 1200 1.45 1.77 2548 1200 1348 25.0 1500 1.21 1.47 2568 1500 106E 00.0 1800 1.04 1.27 2587 1800 787 35.0 2100 .91 1.11 596 2100 496 40.0 2400 .82 1.00 2639 2400 239 45.0 2700 .74 .90 2652 2700 -4B 50.0 3000- .68 .83 2686 3000 -314 55.0 3300 .64 .78 2762 1500 -508 60.0 3600 .61 .74 2855 3600 -745 65.0 3900 .60 .72 1002 3900 -898 70.0 4200 .58 .71 3138 4200 -1062 75.0 4500 .56 .68 3206 4 500 -1294 eon 4800 .53 .65 3255 4BOO -1545 85.0 5100 .52 .63 3351 5100 -1749 90.0 5400 .50 .61 2436 5AOO -1964 95.0 5700 .49 .60 3547 5700 -215. 100.0 6000 .48 .58 3650 6000 -2350 THE MAXIMUM STORAGE IS 1657.10258599 CU. FT. I The time of concentration is 11.89123 minutes. The Undeveloped flow out is 1 c.f.s. TEN YEAR STORM CALC ~IAC~MDNTi 57A"T~ NtiRTH (,114 p,~i~iTlvPl Nt7 , X21 kG C k u L- PJ N'S ` 1zg /94 A54N NgITH 4fF ~~76 AF, Y-,FL.~P~P A ~AV r. pNv~A 5T. ~S~O.~ba~C~B l[?,.Z~ ~.Sg FTC b.Z Ac C~E kocFS Ia...~9Ts - (2. ~.Oav 3fv, pR~v L-oTs @ l Dao F-r a 5~ t3P D F~ ~-o T 1fh Iv.,t 3C,, pEf~-V IRU S s 10--1 t~1&1 6 E C. AlYC~7LA~C1ID tAs 'i lA~a z (.l 1'r- 3 W S-T Fz ItA _3 (3 cF- au-t~ 5"C D fz AGS P F-DV kl>V D z RATIONAL FCJl--dI(JLA HYDROLOGY DATE = 9/2(3/99 DE'SICNI-I; = K W MCMI.Ji_KAN Ll(-i`i_[N "C" F'I= O JECT W-IMC PA 7 Nn TI-1 61-H ADD. L. BA1-i1 A 1 = I. 10 A .RCE; 5U1= ffiR'1 A I FiU!'+1OFF C OF FF f L; I FNT• = . `i' cilJiIr"iRE " = -5 AC'RF) L=rUPri FEE RLINOF-L° C.:f7l-._I=F [C.CENT - a 15 1 CITA.l_- PiREA 4 . 7 ACice P f;i Cd.~I~~POS 1 I-L" RUNOFF [~;C]I -F F I C I I NT - 7R2 97 0 '^4A -T)[ iRL AND ICI.OW FLOW VALUE G CL I , L 5'~` s 1 - .014 C:I • APIIINEL FLOW VALUE!] L - 1 CCJ 71 = . 1 7'' 7 _ 76 l51 . J 4~ 1-D .as L~0MPLl TED Y P L U F!D? 1 UR' = 1zi. 19 92 laT F ~ . ~ s DATE = 97220J94' I]~;TC,IVI f; = is VJ P1EMULWKIN DA11s1N PROJECT P•iANE: - 1.1E N013TH 6TH ADD. t ` - In torl~-,i ty U d c v . Vi n VO ]t Cif'Cll itge (Irarl yy (sL--c-uI 011./hr.~ ~f- .T' .sa.~ -CU Tt.J ~&Ll. FL J 41_ll. ft I}. C} .`00 _ a 1 A 1. C.) n -ri 1f 1 1 1 1 C). 0 ~SC1t_1 2.24 :il. 6 'H64 1 F300 1064 14.,:, t"1115 -1 . 1 . 8 } yam'... '7,2 ~ l F ! lY - =1 •-1 1 ;iii 1 1 . -1 S 2. _ 1 M'$, 14 360 0 --166 2S.0 1500 14 2 7 1. 912 z14 1iva(lart ~1t)~°7 C] „ 0 1 f 1C1 1 11 C14 1. 61 5400 19115 . CY 1 tart . ~ I. Iq S 45 630C) '2400 1. 7 c , 97 . Ca ~7rY~~ .74 1 . 1c3 ° 1. f3 l1C1c~ °`at3 ;CY. 1C1 . 6FJ 1 . 00 55) 7 yf;)frt_) ~"1 41 7(-)o d 1 02 -"fa~a. 99C)c) -6247 7600 . 61 .97 '77:' 10 @o 3 -7(S `,C?0 .60. .95 7964 1 17C?a`) -77-°6 7(_! . -`{i TOO A 5kG . SAWS -.11 ~i E.i 1 26CI 1 `-0460 4~1C3f7 .56 412 2 A' 1 `a~paY 927 34 41,(89 1 440(l -101 L 1 C3Ij 5100 . s 8:, 1X1.1 1 . (oc) C.z3f~7 I 9i ± 1 5 400 ICY . 79 `a ' 1 fly i 14 i -11677 qC .O 5700 .49r .78 gf,,66 1 71OO -174',4 1 i,1Ci . a_1 6L) 1[_1 .49 . 76 4000 11 1C1i,1 - 1712 00 THE ["A 1 MUM STC3I;F`iG IF) 11-'>:,.5924 CU. !---T. Ti°1r Lime of coric_er l ration ,13 14.r197. .1-I In L1i1_tE-115 The L]I-i L ievc-5I to p L'_" CJ i 1 ri W 0L-It 1 S c 'f . Vii., . TLN 'SEAR' 7TC7RM CAL lam' RATIONAL FORMULA HYDROLOGY DATE = 10/7/94 DESIGNER = K W MCMULKIN BASIN "C" PAVT. PROJECT NAME = R.E. NORTH 6TH ADD. DESCRIPTION SUBAREA 1 TOTAL AREA OVERLAND FLi Ct L N C = STORMWATER DRAINAGE .24 ACRES - .24 ACRES DW VALUES .15 = C~ .4 . Q1 SUBAREA 1 RUNOFF COEFFICIENT = .9 COMPOSITE RUNOFF COEFFICIENT = .9 CHANNEL FLOW VALUES L = _•,2 Z 1 = .172 Z2 = L.6 N - .016 S .007 TO _ .163 COMPUTED VALUES OUR = 5.00 110 = IS 010 - .69 DA - .69 R~ a?~-VketkG A0 LaW POINT , ScTA. 3 1 t 9 $.1 8 le-l ~ b.1~3 ~ I7~?~In o~ W ~~e.r a~' en'rX`a+n~e 0.69 (-Fs Cot l ,~e~k rai-e- of -Flow { z ~L}~~-[~ ~vr l 0.163 ~ 'h D • G ~ Q D. ~ 9 0 C, Ilk R15 0 ?f~ NiKG 11 4` wide- t 8" d&-eF r r~ SPOKA&E CouNrY IsopluVials of IQ year 24 hoar precipitation in tenths of an inch. 20 2 4 26 2s . Deer Park i ° r~ 30 26 $4 i 22 'SPOKANE D ' k 0 Chone k 22 f - T -i 6 Spangle 2U Latah re i k 6-6 k i L FIG AE 4 Sheet I of 2 ..,1. Appendix A; Hydrologic sail groups Soils are classified into hydrologic soil groups (HSG's) to indicate the minimum rate of infiltration obtained for bare soil after prolonged wetting. The HSG's, which are A, 13, C, and D, are one element used in determining runoff curve numbers (see chapter For the convenience of TR-55 users, exhibit A-1 lists the HSG classification of United States soils. The infiltration rate is the rate at which water enters the soil at the soil surface. It is controlled by surface conditions. HSG also indicates the transmission rate-the rate at %%hich the water move., within the soil. This rate is controlled by the sail profile. Approximate numerival ranges fur transmission rates shown in the HSG definitions were first published by Musgrave (USDA 1955). The four groups are defined by SCS soil scientists as follows: Group A soils have low runoff potential and high infiltration rates even when thoroughly wetted. They consist chiefly of deep. well to excessively drained sands or gravels and have a high rate of water transmission (greater than 0.30 in/hr). Group B soils have moderate infiltration rates when thoroughly wetted and consist chiefly of moderately deep to deep, moderately well to well drained soils with moderately fine to-moderately coarse textures. These soils have a moderate rate of water transmission (0.15-0.30 in/hr). Group C soils have low infiltration rates when thoroughly wetted and consist chiefly of soils with. a laver that impedes downward movement of water and soils ►vith moderately fine to fine texture. These soils have a low rate of water transmission (0.0".15 Whir). Group D soils have high runoff potential. They have very low infiltration rates when thoroughly wetted and consist chiefly of clay soils with a high swelling potential. soils with a permanent high water table, soils Mth a claypan or clay layer at or near the surface, and shallow soils over nearly impervious material. 't'hese snails have a very lu%v rate of water transmission (0.0.{}5 ntithr). In exhibit A-I, some of the listed soils have an added modifier; for example, "Abrazo, gravelly." This refers to a gravelly phase of the Abr=o series that is found in SCS soil map legends. Disturbed sail profiles As a result of urbanization, the sor] profile may be considerably altered and .the listed group classification may no longer apply. In these circumstances, use the following to determine HSG according to the texture of the new surface boil, provided that significant compaction has not occurred (Brakensiek ::nd Rawls 19133): HSG Soil lextures A Sand, l0amy° sand, or sandy loam 8 Silt loam or loam C Sandy clay loam D Clay loam, silty clav loam, sandy clay, silty clay, or clay Drainage and group D soils Some soils in the list are in group D because of a high Water table that creates a rlt aiiiage problem. Once these soils are effectively drained, they are placed in a different group. For example, Ackerman soil is clas,itied as AID. This indicates that the drained Ackerman soil is in group A and the undrained soil is in group D. (210-VI-TR.55, Second Ed., June 1986) A,1 Exhibit .Art, continued: Hydrologic soil groups for United 5Lates soils FREEST C I fLK,$tic#0 C I GAPCOr 0 1 GCO 0 1 GILISPIC 0 FWEESTOwc F C J FUa5I4we C I G.PO O J GCE C I CILLA.O C I tt10.14 0 J PLLION 0 1 4.PO. DRAIwEO C I GEtaURG C I CILLEhOER a fkCEr4Ica a I fL4.15 0 1 G►AAaaTCR d 14Ctmoae C I GILL LA* C FAtLLChER P I OULVIOCR D ! 4aAA C 1 creQ 0 l CILL IGAN 0WetjLOUI a J 01 U..IC4 0 1 4Aw[i4 a 1 GLCAISLn a . I GILLS a C FULLSOUF4 f Ae.runr D ! I WU.T F I CAUfp a I GEia a I Gl" SaUPG C r QEa C I PkMk 155 0 I Gave UT r 0 ! GE I SCL a 1 GiLA.. a fOthcw a C 1 f4WSnuA 0 1 4.LC 0140 C I 6E149 C 1 C. ILr.13RE C 4FRE^44nCACCR 0 1 FWT 1 Iu4T. OQAINeR 0 C 1 400cfs I GAP CIIL L! C GCLAIC atp 0 Le -8 4 FRtwChJCiyr C I fuS UlIka P I GAvc If A$ I C I GEM, sTOar C 1 G 1 G16AIn 4ILQQW C fRCw[nr.■p d I fu5Ur4f4 C I GAAC0I4 C I Gt.lD C 9 FRChCnT0.r1 0 14A4sYQA C I GaAOELLF` 0 1 GLrSOw I ~ I LT I oil fo CI LT GE 0 f Af SMr41ta O I CAD/6301. a ! GARCLwA F 1 494&v 0 1 4lwLErl fAESrr0. 0 I 4.466 C ! 6A11111htf A I GewerRar G I Lln.r d aaL6PML-A4.AA6J fwESNO Y I 6A041Y466Y 0 i 6,00wCR1S FOLK h 1 4ChESCt t! 4lxt■ a 0 . wICK S06Loft C I G"LL C I 46HO1.tNYIL6C C I Gee.ErA d l 41•4[A a fh4:.4 { 4ADICA 0 1 4A404i4C • I GEMOa 0 I Claf o fQElw1K a U { 4.61NO L At L T I P 1 F 1 4C'i.06 d f ftQ 4IwlA p rAt.aA 0 { .6ACH600 0 6aQFA 1 GAQF It 6P I C GEIrI i L L T 0 1 C. I wr. 1 A C Fri 1-4T O i 4.CiaA 0 1 GAFnl6L 1 0 1 GtwrQr G D I GI kaIDLO C J G&Does C 1 GAA IItII C 1 LOCOnp■ 44CnflocA C{ GlOAQ.A0 0 p *F%OLQ i C 1 LA001 a i GAG lJA t l 6CORGCC4LfA d I d! L14.G00T LARD p 41LOr ialfh05 C ! G•otoc4 C 1 GfRLAND a I 490l.LfTOrw D ! CYSI 6 p fRI.aOS+•IP C I 4AOS00w. ■Er C 1 GEOAIGLrILLf a I GIIaKDA C iWtES a I sUat144Tuw I GfriLOCrr 6 ! CCOALIa C 1 G!i•. a fAlC3L a..0 3 n P G►g.tkL 1 4•GCOr C I GAh..pra C I GCPrOWO G I Clr lrr C S ! 6.Gt10.% d C l G.P"P( l 4rhgEL 0 1 GEPa 6 1 GLACIEDCPCC6 FA1iaLC ! G.GIL ? 16awnt0 r I GCYIrCbr C! G6r0GL6 a FQlhFS C J GAwEE e J 4ARn4: 0 I GERALD 0 + 460Ct6 a F"G 10 S I Late 0 466 0 I At ! 10CA4•fa 0 1 LLAOfTILL.r 0 f417hA C 1 6a1L4 1 0 I GL"ALM 0 1 6a,AaEraICA D FWI]tgM C I G+ihtS 0 C 1 GAWA I GCGIw4 a{ GG►pilCn( a fR1aP ■ J G.INA;%QC40 C a HCYS,p~ - I GtAL■Cn D l 4LAarlw " FR{.CO 0 1 4A1hESr14 LF A T( I I LIWLANt a l LLa5G0. C fQIsIIe a . . 1 Lot at ■ 4+R415:114 E I GENIC d l GLar.SwLA G f1.i7I a . 1 Ga*aWfIn D a J I 4 N5 'd I GE4wAwT0614 a 1 4L- At a FQIIICLL C ! G.6Cr.4Tl C A 1 1 GAFTCN f I GEwr.I,T r I GLf►50r. fkvUCA4 0 1 4A6i C 1 GC4..CCr I GLLCE C c f WU60 3 1 6►6Ln Ir l 4ARYf4Q1. C I GtW4.i4 e C V (.6[m a f+:Otiw.ti C G ! •l t0 F f 4•9r lr O l 4C6A.40 C 1 G6Ewn.A a iGOL IC i G 1 .LtST 1h• 6 ! 4P4r17. ai®I 49W4AA0. DAAli4 ED E 1 a CL . At I C i&361C. C I G■LC$1911" ■ 4, -F it ! Gas 7Pha r ! O GC ! dcfi e GLi•a4 a •LtrATlOarCSRD7 I CAL ET a d I GF13.11 f E e I LLEhalaiA C ~40LlC. f600090 r. ! CAL ILfe C l Las CLECC N GASCC•.a0• G 1 0 GtSS+•FA OtOl GL.1.PAgOa 0 +Wann4Af a ! r.6!`1F0 C Ga5I6 1 GtSlrlr 0 l 46fi.t+Ma F fpun rEw■ C 9 { GA61SICO. C { :.aSGL.IT P 1 4FIAr.r a I 46 Cr+C ■Aa. .Er. C f ~0ar1 IC 4+ C I SaLIM:-.6CALl 1 4A4S►rAT ! 0 GElCnf66 C I 5.61+•C . J+rI O+. G 1 y.6 LAw0 r G■SSr16LE 1 C 41 Taa1L 0 1 G6C sC Of ar0 iW;ST 3 I rA64•TIN C I Ga~j 004 ! C GFTIrs C ! GLEwCO9. 0064000 0 iQ0lAA0 C { LaLLf GaS d 1 Gar• I 41 II W ILL[ 0 V QI fMOALF r F6uIIA a 1 G■6LIA1 a I GAICS r{ 4t.rtf, C 1 4LtnDAkC. rLT C FQUIYFICLO A I GALL IA F 14AI(SCh f l 4tysta C I GLChD•LL. AAAELT C r iuIIKURSI C I GAL6l r. d l CHIC qlE. C 1 d 410OLLR G C I FLOa 0 FpulTka..D 9 { 4ALLIgM a l GATC►fr 1 1000w a l LL EMOE Q $ ON a FiUlILap0. C 1GAk6NAY 0 I'4A If.I+4P C I C GId40hSCAEEA C I GLE.0ITC a 060.pr 12lT ■Cr i G.L6tilr t t Ga{LIy I 6100s 0 1 4LCr.00AA A10 F Q U I I L A1r0, r~T C I G/LOO Cs01 4alOW a ! Gitw4T C I GLEhiDCw 0 f4 If { I G p { GlaSOYTl66C 1 4L1wLLC fQTESUR4 a l 444, 44 r 14#ULF4LOW f i GO.C66 C C I GLC..iOAD C F1, 0puw C, I LALVC SI ■ I 4AUL C~ O { C I G J0E0w 4IC a C 1 GLfw..~6k 6 Fl. (.61C EM 5 ! GaL y: C 4 i GAwt6 6 . C ! GLiir+rrr a frre a®, C I CrLVIN a l 4.4{4an C ! C GIfF010 1 FUAyIE 0 { G+tir•T A 14ATIns i A4,P 41 C C ! C.h- GLL a C +uLL3 C ! GA.ra LLR C f GArIp1A 0 ! 6 GILa a ! 6LC,w..trC+4 C FWLC05TA 0 I G"4044 a• 1 GAT 0 1 6iLaLPr a I GLC~0 C I LAmILL C 14aTLt%VILLC 40001 64L a0a a l CLEm 046 ► ~v4..FC 4 I IA..■OU 0 . ! 4•T6UHO a I id I a LLC rr+i g ruG..EB C { 4•MCC C I G}Tnsd C I C GALCOPLLT I GLLMaDSC a FukCwaA [ I GAaO~ Q 14ag4JL6f I O C1LCa a' J G6E+.Wass c FulOA ClD1 G+nis L` I GiLCACST d i GGfhslLO a FW"A0 C 4Ar.ME T T I A I GAIDS 'D I GI L C 1 469 h Ion n FULL; P 0 4.r.S6694 ' i GALrrLL' C I 96 G ILLS a I GLEr.lOw. 091 C F46LC0404 h I G#MIMLA► POrrOLC D I 4L►CnAAI [ 1 4lLr0p0 trip! LLlwlpSn • FaLMfP 0 I Gall a i GCA..4 61LfCWa. D I 46CnTlL. a FuL-CW. ORAINCO C d L.A7uITC a { CCg;,G+r C 1 a YTRAfir lLg ! 46E C I Si.a514alUw { LLCft Fo1% 0A1 Y DRAINAGE EASEMENT DESCRIPTION A temporary drainage easement over that. Portion of the NW 114 of Section 25, T. 25 N, R, 44 E.W Ni described as follows: Begin at the NE corner of Lot 2 Block 1 of RIDGEMONT ESTATES NORTH 1ST ADDITION, thence S 99'23'17"E, along the South line of 1_at 1 Block I of said 1ST ADDITION projected, 220.00 feet to the True Point of Beginning; thence N 00°36'43"E 140.00 feet; thence S 89'23'17'E 240.00 feet; thence S 0U°36'43"W 400.00 feet; thence N 73°40'46"W 166.21 feet; thence N 00°36'43"E 40.00 feet; thence N 49°34'ST'W 78 10 feet; thence N 00°36'43"E 125.00 feet; thence N 89023'17"W 20.OU feet to the True Point of Beginning. A . r j j I / ~d f II UNPLATTED 220,00' S89'23'17"E ^o f 0 f ?a.c fN89'23'1 3 pLO rt] C3 - `-j -rv~- r I i I 1 i s G7 a i C] I r -_----r------ i ~ I 1 l f I I I I I f I 1 I I I 240.00' 89'2Si 7'k E lo 3 - ~~:2~ 4 ~ i~ Q ~ C] ~ ~ Q / G cn !•111.111E-FJ1EG=E:THE TI_1FPEF, GF. 1~ ~~_~1c51 l,.0; Nanh, ZQ Airmnrlc ''-1 "'POVAnc. VA 992) z Fati• j".92r.1510 TRANSAMERICA TITLE INSURANCE COMPANY CERTIFICATE OF DV?NnRSHIP This is to certify that Alfons B. Renz and Hilda E. Rent; Bruce B. Butler, Trustee. Bruce B. Butler., F.S., Profit Sharing Trust; James P,. Wilharm and Mary Han!,,y, Co-'Trustees. Evergreen Whole- sale Lumber, Inc., Profit Sharing Trust; Brian Jen.ner, Trustee, Brian .lenrier, Inc. , Pension Trusty: Fern S, Klaus, a single person; Tony Higley, a married Man dealing in his sole and separate nronnrt•r ; Stine 0, Daub la,e ; Terrence R. Whitten and liar j orie. P. t•Thitten, husband and w 0e, Kenneth J. Tupper, Trustee, Tuner, Inc. , Profit Searing Trust; Delores Douglas; Richard 1.7. McF€>cchran and Bruce A. IlcEachran, Co-Trustees Robert 1.7. McEachran Life Insurance Trust, dated ra 10, 1952; and Jack R. Felgenhauer and Gloria F. Felgenhaver, hu"band and -life are the owners of record as to the following described property, being a portion of Assessor's Parcel No. /A5252.9071• Sullivan South Enterprises, a Washington partnership, is the contract purchaser. Dated this 15th day of Alagust, 1995. naureen Wild Title Examiner lr C1. qt. C i .rol• 11 i1.1.. k 1.% a .,I- t•1HIDE;Ft1EPE/THE TUPPER GP. P. G14 .r D1[A NAGrs EA.SUXENT DESCfiitrr1ON A lctbparnry drainage astnient over duct portion of the NW 114 of Scciialt 25, T. 25 N., IL 4-1 1r. W.M. dcscritxd as follows: Begirt nt the NE corner of Lot 2 Block i of TuDot:moNT ISSTATES NORA 1 ST ADDITION; thence S 99"23' 1 TT, along the South line of Lot I Block I of sold IST ADDITION pmjcctfid. 220.00 Ihct to [he Truc Point of 13cghudng; thence N 00"36'43"E 140.00 feet: Utencc S 891123'17"E Z-IU.00 Meet; thence S UU036'43"W 4UU.00 feet; thence X1 73°40',16"W 166.21 feet; thence N 00"36'43"E 40.00 feet; Ilscnce N 47°W5 7" NV 78.10 feet; 1ltcucc N 0n036'43"E 125.0[1 feel: thehee N 99023' I7"W 70.110 feet to the Ttuc Point ofEeglnning. `e REV EW CONIMEWS SPOKANE COUNTY DWISION OF ENGINEERING & ROADS 1026 W BROADWAY, SPOKANE WA 99260-0710 PI-TONE (509)456-3600 FAX (509)3243478 Dean Er REVIEW i REVIEWER: ~ PROJECT P-1684E DATE: 20 Tune 1995 PROJECT NAME: idgemnnt Eaates PST. fdh Add, These comments'are to be used in conjunction with the-road and drainage plan redline markups, which are attached. Address all comments by revising the plans and drainage calculations, unless otherwise noted. 1st Review: G4) The 1218' pond located at the easterly terminus of 17th Ave is located outside of the plat boundary. As such, a separate drainage easement will need to be created. Provide the following documents so the easement can be prepared: a) legal description; b) an exhibit of the easement drawn to scale and placed on 8 x" x 1160; and c) a title report of the property(ies) which will be encumbered by the easement to ascertain proof of ownership. Once this information is provided, the County can prepare the easement document. This 1208' pond will need to be owned and maintained by somebody. The County will not accept this pond. Therefore, submit a proposal describing who will own and maintain this pond. This item is pending submittal of the information needed to develop the easement documents 06- G5) The Owner's approval signature on each plan sheet will need to be provided by the final submittal of the plans. oy,,G6) The Hearing Examiner's Committee Conditions of Approval require that 16th Ave. be widened and improved to County Standards along the a street frontage. A phasing agreement has been established between the County and Developer's representative, Have Renz. A copy of the phasing is attached. Road and Drainage Mans Road Plans/Profiles Sheet 1 1) The berm is to be shown in the profile. Note: it is understood that this 12081 pond is temporary. And when 17th Ave is extended outside Ridgemont Estates N. #6, this pond will be replaced with a new facility. REVEEW C(3NEMENTS Page 2 of 2 20 June 1995 RE VEEW # _L PROJECT # -P-1684E PROJECT NAME KWgemo ,states N. 6th Add. COMMENTS BASED ON PLANS AND CALCULATIONS IN THIS SUBMITTAL General fits p[C 1. The attached Standard Notes are to be incorporated into the plans 2. The Drainage language is to be incorporated into the plat dedicatiop. The Drainage language will be provided once a proposed maintenance mechanism of the off-site temporary pond drainage facility is provided and agreed upon by the County. See Comment G4 above. Ut Mans 1. The 248 Swale berm elevations, as shown in the plans, is to be indicated in the lot plans. *5!mp6on Engineers, Inc. CIVIL ENGINEERS AND LAND SURVEYORS N. 909 Argonne Roads Spokane, WA 99212 (509) 926-1322 - Fax: 926-1323 TO: Dea% FrAvvz P -r=. av-av%e Couitt F-YI ►heers SUBJECT: i Nnvn+ Esta~'e N v rtt► 6TH A d d i-ki av► DATE: la► us z lgq 5 lhGt~Ade.d ibr LrLr jeer i eW cAre- r rots of kc re.vise S'6-ee.j' (XKA c~lrai+n~t ~h 5 ~~~~e 0.k'e ie.s Of tKe dram%o, a easeiw~ilt descrti fi vl are e. j%i v-f tke e.owse mehf ail a~ it1e Ire aIrt Of +~e Ir a 12 e- v-+4 e- v% tAtn6erej 16 u Aite e-cLsemevk+ ke fsife ~rai+~~► cis i~~ owhed ai w~~' as ih b . 1. C sKA A~s0} . hC-1t&4'j iS 0. r-0 b~ h l dv- Ai 4 1` e~ Art CAVE topes e i a 1,[ at A "~'c~W►, ~ oc ~ 5` e~ of rv~e5si ~hat~ e. ~rie.eY-, ► C- e-v V\ E. i Signed ~ -W, I&28k:~3 Easement Log Plata Reviewer: Project Name: Contact Person: Project No. Developer: Easement No. 1 Description: Easement No.,2 Description: Log Dates Log Dates Easement Number 1 Easement Number 2 Legal Description & Title Re t R d f E _ r por equeste rom ngr. Legal Description Receives ] Title Report Received 2 Legal Description given to Dave B. to check Legal Description Approved b ~ y Dave Berto Easement Document Request G T R M - r iven o ay oors Ray M. Sends out Document Signed Document Received Easement Recorded Notes. (i.e. Recording No., etc.) 4 SUBMITTAL CHECKLIST PROJECT # REVIEW # ~ REVIEWER: DATE: 15 June 1995 PROJECT: 1*~ MRM AbUk l't AW r7a,4 PROJECT SPONSOR: TEL # 'f3 PROJECT ENGINEER:. 6I TEL # (Road & Drainage Plans) PROJECT SURVEYOR: 'PEEL # (Plat) ADMINISTRATIVE REQUIREMENTS YwD Nn ® Nan E] 1. The $100.00 fee and Agreement to Pay Fees for plat review have been accepted by Spokane County for this submittal. Yea 0 No 0 wA ❑ 2. The Review Fee Account is current (no invoices over 30 days outstanding). Y. Nn 0 N/A El 3. I have noted the plans in, plans out dates on the pink sheet in the file. Yea ❑ M O NIA 4. If this is a mobile home park project, were plans routed through Planning? Yea T No ❑ N/A 5. The file contains a Spokane County Engineers Section snap, Assessors's map and aerial photo. Yea Nu E] NIA E] ti. Field review made. If yes, complete attached form "Field Review Report". PLAN REVIEW REQUIREMENTS Yea No ❑ NIA ❑ 1. Yes NO 0 NIA C] 2. Yea ,0NIAE] 3. Ya©m' rmAll 4. +0 -ElmE1wAE1 5. Yea No ❑ N,A ❑ 6. Yea k Q mA E) 7. Yes ❑ NO Q NIA ❑ 8. 2 copies of the plans and a bound drainage report were submitted. The plans are on 24" x 36" sheets. The plans and calculations are stamped. Plans must be marked "Preliminary " or "Not for Construction" if they are not the final approved plans. Final plans must be signed and dated by the responsible Washington State Professional Engineer. The developer has signed and approved the Final Submittal of the road and drainage plans. The Standard Plan Notes have been included on the plans. Is the project located in the Aquifer Sensitive Area? List any design deviation requests and their status: NQ%V Locate the Findings and Order for the project and list any unusual conditions: Yes 0 No 0 NIA ❑ 9. Street names are consistent with Plat. FLOOD ZONES Y. ❑ N.11 NIA El 1. Does the entire plat lie outside of designated 100-year Flood Plain Area? Y. ® NQ 13 NfA ❑ 2. Does the entire plat lie outside of Zone "B" of the designated Flood Plain Area? Yes 13 N. F] NIA 0 3. Is the max. street ponding in any part of a Zone "B" less than 1'? V. ❑ Na ❑ NIA El 4. Does the plat contain appropriate language limiting the lowermost opening in a structure located in a Zone "B" to not less than 1' above the lowest road elevation? Yea El NO El wA ❑ 5. Is the entire project located outside of an identified Flood Plain Area? V. ❑ N. F-1 NIA 1:1 6. Is the entire project located outside of an identified Stormwater Management Problem Area? ckhstv4.0/Ian95 1 ROAD PLANS 1. List any roads that must be designed and constructed on the project. ROAD NAME ROAD NAME ROAD NAME ROAD NAME ROAD NAME ROAD NAME ROAD CLASSIFICATION TRAFFIC INDEX (1) TERRAIN PAVED WIDTH RIW WIDTH POSTED SPEED DESIGN SPEED MINIMUM GRADE MAXIMUM GRADE STOPPING SIGHT DISTANCE MINIMUM HORZ CURVE TYPE OF CURB REQUIRED MIN ASPHALT SECTION MIN GRAVEL SECTION RITRAFFIC INDEX: Maior Arterial econ arv Arterial ❑ ector Arterial ca Access/Resi dential. ovate . Yes ❑NO ❑NIAEl 2. yes ❑ No EINIA ❑ 3. Planning conditions require submission of a landscape plan. (NOTE: Usually associated with PUD's). I have checked the landscape plan against the road and storm drainage design. If there are any conflicts, list them in space provided, or note that no conflicts were found. Yes ® No LJ NIA LJ 4. The fallowing road plans have a bearing on the design of roads for this project and a copy is in the file: Yes 13 No ❑ N,A ❑ 5. Vertical curves meet stopping sight distance requirements. V. E3Np ❑ WAD 6. An "R° Value Test is required for this project. Yes 0 Np ❑ NjA ❑ 6a. For this project, for each soil group called out an "R" Value Test has been submitted. v. ® N. D N,A O 6b. The pavement section is adequate for the "R" Value Test and required traffic index. Yea ❑ No 0 NIA E3 7. Is the bench mark called out on the plans? Yes D Np ❑ NIA ❑ 8.Are stationing equations shown? Yes ❑ NO Q NSA ❑ 9. Is stationing correct (south to north, west to east, reading left to right on the plan)? yea ❑ No ❑ NIA ❑ 10. Are existing utilities shown on the plans (or an information copy of the utility plans submitted)? yea ❑ NO 0 N!A ❑ 11. Are proposed utilities shown on the plans (or an information copy of the utility plans submitted)? yea 0 Np ®NIA ❑ 12. The project plan name matches the plat name. cklistv4.011an95 2 Yee ❑ NO Q NIA ❑ 13. STREET WIDENINGANTERSECTION WITH EXISTING COUNTY ROAD Yes El No ❑ NIA ❑ 13a. Are curb design sheets provided for widening of existing streets? Yee ❑ N. ❑ NIA ❑ 13b. Does the curb design conform to Spokane County Standards of section cross slope (Between 2 % and 4.5 Yee El No El NIA El 13c. Is there a street cross section shown for widening existing streets? Yee ❑ NO ❑ NIA ❑ 13d. Does the proposed new width thatch the width required in the Findings and Order? Y,. El No El NIA ❑ 13e. The cross-section shows: Existing RIW, Proposed RIW, any required Future Setaside, and edge of existing and proposed pavement. Yes a No ❑ NIA ❑ 13f. 100' (min.) pavement taper into project is shown. Yes El No ® NIA E] (1) There is adequate RfW for the taper to extend from the new paving width to existing pavement. Yea ❑ M 0 NIA ❑ (2) There is inadequate RfW for the taper to extend from the new paving width to existing pavement; taper extends from existing paving to RIW. Yes El N. El NIA ❑ 13g. Length of pavement taper out of project meets. AASHTO requirements: WS'=60 for design speeds 5 40 mph, WS for design speeds > 45 mph, or feet has been approved by Spokane County Traffic Engineer. Yea El NO ❑ NIA ❑ 13h. Transition from end of curb to existing paving is shown (curb should nose down in 12"). Yes El Na 0 NIA El 13i. Are the curb grades, for any required curbs, above the county minimum of 0.8%? Yn ❑ Nu El NIA E] 13j. The curb type meets Spokane County Standards. Y. Q Na 0 NIA ❑ 14. NEW STREETS Ya El N. El NIA E1 14a. Does the proposed alignment meet Spokane County Standards? ,r El N. E1NIA El (1) Centerline slopes are within Spokane County Standards. Ycs El Nn ® NIA E] (2) Vertical curve lengths are adequate for intersections and stopping sight distance. Yea 1:1 NE] NIA 1:1 (3) Horizontal curve radius meets Spokane County standards. Yes EINo ® NIA E] 14b. The plans show the typical cross section for streets. Y. 1:1 Na 0 NIA 0 14c. Does the proposed street width match the Findings and Order? Y~ E1Na ❑ ,AE] 14d. The typical road cross-section shows: Existing RIW, Proposed RJW, any applicable Future Setaside, edge of new pavement and any other required improvements. Yes ❑ Na ❑ NIA ❑ 14e. The typical road section on the plans shows the cross slope and it is within the 2 % to 4.5 % standard. Yn E] ❑ NIA (1) The Cross Slope is correct when checked on the profile drawings. Y.e El N. ® Na El 14f. Curb type: is shown and is the proper type for the road classification. Yea 13 Na ® NIA 11 (1) Meets Spokane County Road Standards for curbs within the public right-of-way. Yes 11 Na El NIA 11 (2) Consistent with the curb type in the general area. Y. ❑ N. E] NIA ❑ 14g. Are the curb grades above the county minimum of 0.8 W. ❑ No ❑ NIA ❑ 15. Has the Fire District approved all proposed private road turnarounds that are substandard according to our Spokane County Road Standards? (A one lot stub less than 154' on a public road is allowed). ckli=4 0/lan95 3 Yea Nd ®N,A 16. SIGNAGE PLAN Yea E]?~- 0 N/A ® 16a. Stop signs are shown for all streets which intersect an arterial (Check with County Traffic Engineer if there is a question). Yea ❑ No ❑ N,A O 16b. Street name signs are shown at all intersecting streets. Yea ❑ No ❑ N,A ❑ 16c. Is there a need for barriers at the end of dead end streets? re, 1-1 Na ❑ N,A ❑ 16d. Is there a need for other special signing? (Check with the County Traffic Engineer). Yes ❑ 0 N,A 11 17. CURB RETURNS Yes 1:4o Q N,A 11 17a. Are BCR, MCR, and ECR stations/elevations on curb returns shown in the plan view? Y. Q Na E]N,A ® 17b. Are the curb return elevations correct? Yes D Na ❑ N/A ❑ 17c. Is there positive drainage from the road intersection to the MCR? If not, is design safe according to AASHTO standards? Yea ❑ Na ❑ N,A ❑ 17d. Curb return radius meets the Spokane County Standard minimum. (to back of curb for rolled/wedge curbs, to face for vertical curb face types)? Yea 11 M ❑ N,A El 17e. BCR, MCR, and ECR elevations are set to allow drainage from the centerline to the curbline? Yes ❑ Nu ®N,A 11 17L The cross slope between the intersection and curbline meets AASHTO requirements: (ref. AASHTO) 10% (flat terrain); 8% (rolling terrain); 6% (mountainous terrain). Yes No 11 NiAE] 18. CUL-DE-SACS Yea E xa ©x,A El 18a. The cul-de-sac grades (top of curb) meet county cul-de-sac standards (1 % min.) Yes ❑ Nn El ❑ 18b. The cul-de-sac curb is shown in profile. Y. ® Na ❑ N,A ❑ 18c. The cul-de-sac radius meet Spokane County Standards. Yes ®Nu ❑ NIA ❑ 18d. The center of cul-de-sac Station is shown. Yes ❑ m ❑ x,A ® 19. INTERSECTIONS Yea O m ❑ N,A ❑ 19a. Intersections meet AASHTO sight distance requirements for controlled and uncontrolled intersections. Yes ❑ Na ® NIA O 19b. Intersection separation is greater than or equal to 150' on local access streets and 300' on arterials. Yea Q w 0 N,A ❑ 19c. Do the intersections meet the landing requirements? Yea ® NO O N,A E] 19b. Wheelchair ramps are provided at intersections with sidewalks. Y. El N. ® N,A El 19c. The intersection horizontal sight distance analysis shows that sight triangle encroachment on private property is 2' or less for controlled intersections. Yea E] NO E] N,A E] 20. Is there a need for slope easements? ckt M4 01)an95 4 Yes u Na Q NIA 0 DRAINAGE PLANS Yea 0 No 0 N,A 0 L Has a plat map been submitted which shows lot dimensions, street widths, etc.? Yea 0 Nu 0 N1A ❑ 2. BASIN MAP Yft 0 Na 0 N,A 0 2a. North arrow and scale is shown. Yn 0 K. 0 NA E1 2b. Subbasins are labeled and correlated with calculations. Yes 0 Nn E] NIA 0 2c. Was a map with contours/spot elevations submitted to properly determine drainage basins? Yea ❑ NO 0' NIA ❑ 2d. Were the routes used to determine time of concentration shown? Yea 1:1 No ® NIA 0 2e. Were all existing drainage courses shown? Y. 0 No 0 N,A 0 2f. Were all the proposed drainage courses shown? Y. 0 N. 0 NIA 0 3. Were Hydrologic calculations submitted for each basin? (National Formula if area 5 14 acres, SCS TR-55 if area 7 10 acres). Yp 0 No 0 NIA 0 3a Permission was given to use SCS TR-55 for basins 5 10 acres. Y. 0 No 0 NIA 0 3b. Basin includes offsite and onsite areas together (use 50 year analysis). V" ❑ Na i] NIA 0 3c. Basin is all onsite (use 10 year storm). Ya ❑ KO lI NIA ❑ 3d. Runoff rate for basin is compared to impervious road area runoff rate. The larger rate controls design. CONVEYANCE/DISPOSAL Yea E]No 1] NIA 0 4. Pipes/ Culverts - If, yes, complete checklist section for culverts and pipe-systems. Yea 0 Na 0 NIA 0 5. Ditches are identified in plans and details provided. And have a minimum grade of 0.5%. Yea O Nn i__I NIA 0 6. Are there any conflicts between the proposed septic tank effluent drainage fields and any ditches on the drainage plan? Ye, ❑ No O NIA Q 7. Gutter flow depth is less than gutter height and allows for 6' non wetted area of each side of centerline for local access or collector roads. Yes ❑ NO 0 NIA © 8. Locations where water is intended to flow through an inlet or curb cut are at the low point in vertical curve. YML1 No El NIA0 9. Backwater - Analysis for any pipe and/or ditches was submitted. Yea 0 No NIA ® 10. Headwater - Calculations for culverts were submitted for review. Yea 0 No ❑ NIA 0 11. Curb drop/curb inlets are used in the conveyance and plan and calculations for flow capacity have been submitted. Ya0 Ne ❑ NIA 0 12. Is Erosion protection required and have calculations been submitted for review. vn 0 N. 0 mA 0 13. Soils type is "pre-approved" (Garrison, etc.,) for drywells without percolation tests. Y. 0 No 0 NIA 0 14. Does the drainage report identify the SCS soil groups for the project area and for the proposed roads to be built in the project area? Yp ❑ N" ❑ NIA 0 15. The drainage design maintains existing flow patterns in natural watercourses. Yd 0 N. E] NIA 0 16. The drainage design maintains existing sheet flow patterns without concentrating flows. YWEI No ❑ NIA 0 17. The drainage concept is compatible with The Guideline for Stormwater Management. Yea 0 No D NIA 0 18. The difference between present and future flows is retained on the site. Y. 0 No 0 NIA 0 19. A detention basin concept is proposed for stormwater disposal. If, yes, use separate checklist for detention ponds. CULVERTS AND PIPE SYSTEMS vin 0 No 0 NA E3 1. The road culverts are at the low points of stream flow. ves 0 No 0 NIA 0 2. The headwater was calculated for culvert entrances and is under 2 diameters for culverts under 18" in diameter and 1.5 diameters for culverts greater than 18". Y. Cl Na 0 NIA E] 3. There is a minimum of 12" of cover for all culverts and storm sewer pipes. Yn Cl No 0 NIA E] 4. The designer has demonstrated that the proposed pipe is suitable for cover less than 2.5' (PVC), 1.5' (CMP), 1'(RCP) (HDPEIADS) or the engineer has provided trench details for upgraded pipe bedding for these areas. Y. 0 No 0 NIA 0 5. The minimum velocity within the pipe system is 4 feet per second at design flow in a backwater condition. (Note. The County Engineer may permit lower velocities). Y~ Q Na D N,A 0 6. The backwater calculations show a minimum freeboard of 0.75 feet for each catch basin or manhole. Y. 0 N. 0 wA 0 7. The minimum culvert and pipe slope is 0.5 % and all pipes meet or exceed this standard. Yes ❑ No ❑ NIA 0 8. All angle points in the storm sewer system have suitable access such as a manhole for cleaning. Yd 0 Ko 0 NIA 0 9. At locations where two different pipe sires enter the same manhole the 0.8 diameter points of each pipe are at the same elevation. (Note: Exception allowed for drop manholes). Y. 0 No 0 NIA 0 10. Is there any downsizing of pipes in a systems of pipes that are 18" in diameter and smaller. ckhsiv4 oldan95 5 J Yn ❑ Ns ® NIA E1 11. There is a downsizing of pipes in the amount of 3" for a minimum of 100 feet in a pipe system that contains pipes that over 18" in diameter. Ya ❑ No ❑ NIA 0 11 All pipes in the gripe system are 12" and larger as per Spokane County Standards; 10" pipe that is allowed for connection of inlets to catch basins or drywells, if the length does not exceed 44 LF and the velocity is at least 4 fps). Ya ❑ Nn 0 NIA ❑ 13. All storm sewer pipes are located a minunum of 5 feet from a rear or side property line and have adequate easements for maintenance. vM El No 11 MA E] 14. Inlets on the same sloe are located so that the maximum width of spread for the gutter flow does not exceed 6' (from curb face for Type "A" or "B", from back of curls for Type "R") for major arterials; 12' for collector streets and local access roads. Y" ❑ Na ❑ NIA 13 15. The plans profiles show all culvert pipe types, stations, offsets, lengths, and inverts. Yea 11 N9 ® NIA 0 16. Pipe materials meet county standards for systems that lie within county ROW. (Note: The type of pipe in private systems may be as specified by the design engineer). Y.O Nn 0 NIA ® 17. The culverts shown are properly stationed from centerline stationing. Ya 13 No ® NIA ® 18. Does the drainage system configuration avoid conflicts with underground utilities? Y. C1 N. El NIA El 19. Is there a need for energy dissipation on any of the culvert outlets shown on the plans? Y. El No ❑ NIA 13 20. Is there a need for rip rap around the culvert outlet at any of the culverts as proposed on the drainage plans. va El No ® NiA 0 21. The rip rap that is shown for the drainage plans is adequate for the culverts where erosion is a concern and the engineer has submitted acceptable rip rap design calculations. Ya ® NO 11 NIA El 22. Pipe anchors are shown for pipe grades greater than 15%. Y. ❑ No ❑ NIA 13 23. There are no instances where water is trapped against a fill with no culvert shower. Y. 11 No0 NIA 0 24. Profiles and cross sections are shown on the plans for all proposed channels and ditches. Y" ❑ N90 NIA ❑ 25. Ditches with eroding velocities have a proper lining for erosion protection. ra 1:1 No EINIA 0 26. Water will properly flow from an existing or proposed ditch onto the pavement as proposed on the drainage plans. Y. 0 N. 11 NIA E3 27. Where the ditch profile passes from cut to fill the flow has been properly disposed of. EKLETS Y" 0 No ® NIA D I . The inlets shown are within the stream flaw. Y" 1:1 No '0 NIA ❑ 2. Inlets are shown on the low side of a road or at the low point of a vertical curve rQC 1 N"0 NIA E1 3. Curb type metal inlets, if proposed, are shown at sags and are properly sized. Ye. ® No El NIA El 3a. Perimeter calculation does not include the side of the grate against the curb face (all grate types). Ya Q No ❑ NIA ❑ 3b. Perimeter is divided by 2 for calculations where no curb opening (Type 1 see standard DRWG B-10) is provided. Y~ El NO ® NIA E] 3c. Area = clear area - 2 for Type 1 grates) va11 No ® NIA ❑ 4. There are no vertical curves that produce areas of very flat grades for extended areas which could pose a problem with ponding water in traffic lanes. va 0 No ® NIA ❑ 5. The centerline road stations, offsets, and invert elevations for all inlets are shown in the plan views. Yea 1:1 No 13 NIA 0 6. Grate type is shown on the plan and is acceptable. (Spokane CounStandard inlets or WSDOT standard inlets in county ROW, on private property other inlet type may be specified) (Type 1: D-2; Type 2: D-4 in old 1981 standards or type 1, sheet B-IO;type 2, sheet B-i l for 1995 standards). Y" 0 Ne ® NIA ❑ 7. A detail drawing of the grate/curb installation is shown on the plans and includes a minimum I" depression and transitions as per county standards for grates that are located within county ROW, or referenced to SCRS std. detail D-8 in 1981 standards or sheet B-18 in 1595 standards. Ya 11 Nu Q' NIA El 8. A curb cut detail is shown on the plans with the new county back drop concrete apron with transitions and a I' depression for curb cuts inside county ROW, or referenced to SCRS std. detail B-8 of the 1995 standard drawings Ya ❑ No ❑ NIA El 9. The plans shows acceptable curb cut details and grate details for installations which lie within private road easements. (For plans that are subject to Spokane County Review). Y. ❑ No ❑ NIA El 10. If inlets are in a gravel road or a dirt ditch a 6' x 6' A.C. apron is shown around the inlet. YQ ❑ K. 0 NIA ❑ 11. Catch basin or special manhole details are shown or a standard drawing is referenced. Ya ❑ Na EINIA 11 12. Critical low points in the drainage system have been provided with overflow easements. (Where it is possible). Ref. Page 2-1 of GSM. eklistv4.011an95 is 208 SWALE SYSTEMS Yp ®No 0 NIA 0 I. Is the Swale located outside a future set aside area? See Findings and Order for where setasides are required. VnO N90 NIA 0 2. The Swale bottom and sides have sod or grass turf specified. 11.13 Nu0 NI ® 3. Swale side slopes do not exceed a 3:1 side slope. (A 2:1 side slope is allowed if Swale depth is less than 12" deep. Should only be allowed where constrained by obstacles) Y" ❑ No ❑ NIA 0 4. If depth of water from bottom to drywell rim is between 6 and 8 inches, soil mixture has been specified which meets Spokane County Guidelines. vp 0 No 0 NIA 0 5. Drywell is: Located within 8 feet of the curb line, or a maintenance access route and easement are provided. Y" 0 NO 0 NIA ❑ 6. Drywell Stationing is staggered from the inlet by at least 4'. Ya ❑ No 0 NIA 0 7. Multiple drywells are located more than 30' (center-center) apart. Y.11 No ❑ NIA 0 8. Soil type is appropriate for drywells (perc rate ~t 72"/hr), If not: Y" 0 No 0 NIA 13 8a. Overflow from a swale at a low point will be directed away from building pads by an identified easement over unproved ground or an existing natural drainage channel covered by an easement where an overflow is required. Ya ® No ❑ NIA 0 9. Drywell location does not conflict with underground utilities. V" ® No ® NIA 0 10. Drywell type is specified. Y" 0 No 0 NIA ❑ 11. Drywell rate type is specified (Type 3 -std. detail D-7 For 1981 standards or type 4, sheet B-15 of 1995 s standard Yes 0 No 0 NIA 0 12. ❑rywell grate elevation is: A minimum of 0.4' below the normal flow line at the curb inlet and is between 6" and 8" above the Swale floor elevation. V.0 No 1] NIA 0 13. Does the note: "Wrap the drywell with a filter fabric (Amoco 4545 or equivalent)" appear on the plans? 14. Swale floor elevation is: rQ 0 Nu ® NIA 0 14a. Shown on the drawing. rft0 N9 0 NIA 0 14b. Between 6" and 8" below the drywell grate elevation. Y- 0 N6 0 NIA 0 14c. At least 6" below the normal gutter flowline at the curb inlet for Swale without a drywell. Ys O N9 O NIA 0 14d. At least 10" below the normal gutter flowline at the curb inlet for Swale with a drywell. 15. Swale floor. Y" O No ❑ NIA 0 15a. Dimensions are shown. Ya0 NO ❑ NIA 0 15b. The area matches or is larger than the required area from the 208 calculation for impervious areas. 16. Easements for the 208: v. 0 No- 0 NIA 0 16a. Are shown on the drainage plans. Y"0 No 0 NIA 0 16b. Are shown on the subdivision plat and match the drainage plans. Yv ® No 0 NIA G' 16c. Are of adequate size to contain at least 6" freeboard above the max. water surface elevation for the design storm. Y" 0 NO 0 NIA ❑ 16d. Are tied to the lot corners. va ❑ Na ❑ NIA ❑ 17. The side of the Swale that is the furthest distance from the street should have a top of Swale elevation that is 0.2' higher than the lowest top of curb elevation along the Swale. Yd 0 No 0 NIA 0 18. The normal flow line at the curb inlet is at or above the max. water surface elevation for the design storm or the max. water surface will not pond water more than 12' in residential streets or 6' in arterials above collector classification. Y.O No ~ NIA ~ 21. 248 SWALES YBO N90 NIA 0 21a. 208 Swale fluor area, volume requirements sized properly to treat impervious surface areas. Ya0 N90 NIA 0' 21b. 208 Swale volume provided in accordance with "Guidelines for Stormwater Management". EASEMENTS Y-0 N90 NIA © 1. Adequate drainage easements are shown for maintenance of drainage ditches or pipe systems. Y.13 N. E] NIA 0 2. There are easements proposed or existing for natural channels which cross the property, and they are adequate to pass the 50 year storm plus a 30% added depth of flow for a safety factor. Y. El NQD NIA 0 3. A public drainage easement was provided where public street drainage was diverted onto private property. Yff0 N90 NIA Q 4. The perpetual maintenance of private systems has properly been provided for. VmC1 No ❑ NIA 0 5. The maintenance of drainage systems within Spokane County ROW has been properly provided for. Y-0 No 0 NIA 0 6. Appropriate drainage lari8uage has been provided by the reviewing engineer to the surveyor and/or engineer who is involved with the platting work. Y.0 No0 NIA 0 7. Are pre-existing drainage easements on this parcel affected by this plat? Yes 0 N90 NIA 0 8. Overflow easements are provided from swales/ponds located in low points where it is possible. cklLstv4 O/Jan95 7 ❑ ❑NIA ❑ UNDERGROUND GRAVEL GALLERIES CHECKLIST Is the site suitable for undergound gravel galleries based on the site screening criteria contained in the draft standards for gravel galleries. If no, an approved design deviation is required before future review. Yo ® Na ❑ NIA 0 1. .3 void ratio for gravel free space volume is used or test information is provided to justify ratio used. Yes 0 No 0 NIA ® 2. Perc rate from field test is used to develop outflow rate Yen ®Na ❑ NIA ❑ 3. 10-yr event volume is contained entirely underground Yea Q Na ❑ NIA O 4. 100-yr event volume is contained by a combination of underground storage and above ground storage up to 8" depth Yea O Na 0 NIA O 5. Soil mixture is specified for water depth in pond exceeding 8" Yea ❑ No ❑ NIA ❑ S. Entire gallery is wrapped in filter fabric Yea ❑ No O NIA ❑ 7. An adequate freeboard is provided in any above ground storage pond. Yea ❑ Na 0 NIA 0 Yea ❑ Na ® NIA ❑ 1 Yea El Na E NIA El Yes ❑ Na El NIA ❑ Yes ❑ Na El NIA El Yes E]No ® NIA El v,:, 1:1 No u NIA El Yes 1:1 No 1-1 NIA Yes[:] N. E] NIAE] Yea 1:1,,. 11 s,, El y, El N, 11 N/A0 Y,Ll Na®NIAE1 Yea ❑ No ❑ NIA ❑ Yra El Na ❑ NIA YJKW ❑ NIA El Yea4Na 1:1 NIA Y0, 1:1 NIA Y e ❑ NIA Y,Z N. ❑ NIA El Yes ❑ No 0 NIA Yo1Na©NIA® Yes El Na ®NIA E] Yea ® Na ® NIA Yea El No ® NIA Yes ❑ No 1:1 NIA 13 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. DETENTION POND Releases to a downstream channel or pipe system that is capable of properly conveying the proposed flows and does not cause downstream flooding. Contains 50-yr developed. Releases at 50-yr pre-developed. Secondary overflow to pipe in control structure for 50-year developed. Emergency overflow weir for 100-year developed. Sump prior to outlet to control structure. l' min. freeboard at 50-year design storm is provided. Lawn turf or hydro seeded sides and floor for publicly-maintained ponds or dryland grasses specified. Sprinkler system for publicly-maintained ponds or dryland grasses specified. Berm compaction and lift requirements specified where necessary. Is a 12' maintenance drive to the bottom of ponds needed? If so maximum grade is 6.1. 208 LOT PLANS CHECKLIST b 'A44 -01, T _ 1. Lot plans are required; submitted on 2. The 208 lot plans show: 2a. The lot number, block number, subdivision name, date drawn, scale, north arrow and street name. 2b. Easement dimensions in relation to property lines or corners. 2c. Location of curb, sidewalk or edge of asphalt as applicable. 2d. Setback requirements 2e. Swale floor elevation 2f. Swale floor dimensions are shown in relation to property lines or corners. 2g. Rim elevation drywell type, frame and grate type, centerline offset and station if drywells are ,present. 2h. Curb cut station, normal flowline invert. 2i. Any drainage ditches, their easements, flowline grade and other required improvements. 2j. Shows depth from the normal flowline to bottom of swale. 2k. An attached cross section of the swale or ditch. Yta LJ Na El NIA El Yea Q Na u NIA 0 Yp11 NO0NFAEl Yee Et,❑NIA❑ Yn❑Na❑NIA® 3. Existing easements, buildings, future set asides, and required building setback lines are shown. 4. The section drawing shows the concrete apron, R.O.W. line, and grass sod or seeding if approved. 5. Lot plans have been stamped by a professional engineer on all pages 6. Lot plans are of sufficient scale to maximize the lot size to the 8 'b" x I1 " paper size. (Drawings may be on plain white paper) 7. 208 lot plans were approved on ckfi&M 411an93 s EROSION & SEDR4ENTATION CONTROL REQUIREMENTS Yea D Nu ❑ NIA [3 ,1. Identify the clearing and disturbed areas in the plan. This includes cuts and fills along slopes. Minimize the amount of cleared area. Y. ❑ Nn '0 N/A E1 Z. Provide erosion control facilities which slow water velocities - through the use of check dams, debris basins, etc. re. ❑ Nn O NSA ® 3. Filter runoff from exposed areas prior to discharging into drainage ponds and particularly prior to directing runoff into drywells. Filtering measures included installing temporary silt traps, silt ponds, gravel cone filters, etc. In silt traps and ponds, size sediment storage volumes by determining the amount of silt material generated over a 6 month period, using the Flaxman Method. The silt traps and ponds are to provide a setting zone, and are to be sized in accordance with the method outlined in Section I1-5.8.6 and I1-5.8.7 of the WDOE 5tormwater Management Manual. V. ® Na 0 NIA ® 4. Stabilize exposed areas as soon as practical after grading work is complete, or when grading work will temporarily cease for more than . In wet winter months, temporary stabilization measures will be required throughout the duration of construction. Specify stabilization procedures, revegetation requirements, mulching, etc. Specify the maximum time that cleared areas are to be exposed without protection or stabilization and time of year. Y. ❑ Na 0 NiA ® 5. Stabilize drainage channels. Provide for temporary and permanent erosion protection measures. v'. ® M ❑ NIA ® 6. Provide for perimeter barriers around exposed areas through the use of silt fences, straw bales, temporary interceptor ditches, etc. Route runoff from unexposed areas around exposed areas wherever practical. Yu ® Na 0 NSA ® 7. List routine maintenance procedures to be implemented by the Contractor throughout the duration of construction. Silt traps, silt ponds, check dams, channel restoration, etc. All will require fairly constant maintenance, especially during and immediately following a rain storm event. VC3 Q Nn ❑ NIA ❑ 8. Reduce the amount of mud, dirt and rocks transported onto public roadways by motor vehicles or runoff by constructing a stabilization pad of rock spalls at entrances to construction site. ra ®No 0 NIA E] 9. Provide special provisions for construction under wet season conditions. Refine the season. Yes ❑ No NSA ❑ 10. Provide final restoration procedures, site restoreation, access road cleanup, cleaning drainage structures and ponds, etc. Y. ❑ Nu El NjA E3 11. Include in the plans the standard Erosion and Sedimentation Control notes prepared by Spokane County. cldistv4.011anO 9 Vn0N6 El N1A© 1. V.E]Na❑NIAE) 2. va❑NQdNrA1:1 3. Vex❑NO El NIAEl 4. yes El No EINIA E] 5. Vm❑No❑NIAE] G. Y.ElN.E]MAE) 7. V.ElNoEI NIA© 8. Y.0N.E]MAE] 9. FIELD REVIEW REPORT Field investigation trip made on Date this field report was completed Are there any existing utilities on the project site? (Overhead power, fire hydrants, etc.) If yes, describe. Are the drainage basins on the ground the same as those that are presented in the drainage report? Are there any drainage channels directed toward property? Are there any drainage channels directing water through the property? Do County roads cut off drainage as per drainage calculations? If there are culverts under county roads, does the flow go away from or toward the project? What kind of ground cover exists? res ®No 17 NIA ® 10. Describe any existing channel conditions: Yes EINo © NIA E] 11. Describe channel cross section: Ves E3No (3NIA E3 12. Existing Curb Type: cklistv4 OIJan95 10 S P a I~ A zv E u r r Y OFFICE OF THE CouNTY ENciNEER • A DivisioN OF THE PUBLIC WoRKs DEPART'Dr ENT Ronald C. 1-lormann, P.E., County EngLneer Dennis A Scott, P.E., Director June 20, 1995 Kevin McMulkin, P.E. Simpson Engineers, Inc. N. 909 Argonne, Rd. Spokane, WA 99212-2789 Subject: Rldgemvnt Estates forth 6th Add. Spokane County Project No. P-1684E Dear Kevin: A review of the cad and dr&bWe plans for this project has been accomplished. Areas of concern to us are indicated in red on the attached prints and calculations. Please make the corrections and resubmit them to this office in order that the review process may proceed. Please provide 2 copies of plans with the next submittal. If you have any questions about this review, please contact us at 456 -3600. Thank you. Sincerely, Spokane County Engineers Dean Franz, P.F. Plans Review Engineer encls: Plans (1 set) Calculations (1 copy) Comments (2 pages) Standard Notes Phasing of Project - 11" x 17' sketch cc: project file 1026W Broadway Ave. • Spokane, WA 99260-4170 • (509) 456,3600 FAX: (509) 324-3478 TDD: (509) 324-3166 REVIEW COMMENTS 15smafs SPOKANE COUN'T'Y DIVISION OF ENGINEERING & ROADS 1026 W BROADWAY, SPOKANE WA 99260-0710 PHONE (509}456-3600 FAX (509)324-3478 REVIEW 1 PROJECT P-1684E REVIEWER: Dean Franz, P.EP241- DATE: 1amaa 1995 PROJECT NAME: Ridggmont Estates N. 6th Kidd. These comments are to be used in conjunction with the road and drainage plan redline markups, which are attached. Address all comments by revising the plans and drainage calculations, unless otherwise noted. General Comments } Provide separate er and Ws arse, er plans, or show them in the road and storm plans. is to determine if there are any utility conflicts. Please note that utility structures such as sanitary sewer manholes and fire hydrants are not allowed within a 1208' scale/pond. e2Add a note to the plans requiring the Contractor~orelocate any conflicting utilities prior to construction. e3) Provide separate lot plans for all lots which will be encumbered by a drainage easement. If you need the lot plan standards please call { V G4) The '208' pond located at the easterly terminus of 17th Ave is located outside of the plat boundary. As such, a separate drainage easement will need to be created. Provide the following documents so the easement can be prepared: a) legal description; b) an exhibit of the easement drawn to scale and placed on 8 1/211 x 11"; and c) a title report of the property(ies) which will be encumbered by the easement to ascertain proof of ownership. Once this information is provided, the County can prepare the easement document. i ~ ~ . This '2081 pond will need to be owned and mainn tained by somebody. The County will not accept this pond. Therefore, submit a proposal describing who will own and maintain this pond. G5) The owner's approval signature on each plan sheet will need to be provided by the final submittal of the plans. G5) The Hearing Examiner's Committee Conditions of Approval require that 16th Ave. be widened and improved to County standards along the 1/2 street frontage. The frontage is as shown in the preliminary plat map. This condition may need to be met for this phase of the Ridgemont Estates North development. You will be informed when a decision has been made on this issue. REVIEW COMMENTS Page 2 of 3 3 January 1995 REVIEW # 1 PROJECT # P-1684E PROJECT NAME Ri emont Estates N. 6th Add. Road and Drainage Plans Road Plans/Profiles sheet 1 1) Provide positive drainage from the easterly terminus of 17th Ave to the '268' pond. Indicate and provide a det ail of a drainage ditch. Note: It is understood that this 1208' pond is temporary. And when 17th Ave is extended outside Ridg mont Estates N. 6, this with a new facility. PAJO lblwft) pond will be replaced A A%d f The drywell is to be placed within 8 ft. of the roadway, or provide ll d a 121 wide gravel drive also to be within 8 ft . rywe . of the Please address. For each 1208' pond, list the minimum berm Or elevation to be constructed around the perimeter of the pond. needs to be set at Top of curb + 0.2 ft. ff&CVM 1W 4j 4i Provide a street name sign at the intersection. Indicate in the plans the street name sign is to be in conformance with MUTCD and Spokane County Standards. Where the new road construction connects to an existing roadway, field measure the edge of pavement and top of curb. It appears this has been done, please confirm by indicating in the plans that the elevations listed are "existing". The vertical angle point at 17th Ave STA 1+50 provides an 41inappropriate grade break. Whenever there is a grade break greater than 1%, a vertical curve needs to be provided. Please revise the profile. Drainage Plan & Basin Map Sheet 2 Define the bottom of pond elevation for the pond located along the easterly side of Sonora St. 1208' Pond Section Detail; For the curb inlet, indicate the 2" drop from the normal curb flowline. ® The seeding requirements refer to Pond "A". where is pond "A"? Please label in the plans. Also add a note that the Contractor shall design and install an automatic irrigation system which in conformance with Spokane County Standards. Also as-builts of the irrigation system is to be provided to the County by the Contractor. As / . REVIEW COMMENTS Page 3 of 3 3 January 1995 REVIEW # 1 PROJECT # P-1 WE PROJECT NAME Ri&emont Estates N. 6th Add. 4*XAf " V Druinn' a Calculations ► ' MCAL D~) Whenever off-site runoff contributes to the drainage facilities, then the facilities are to be designed for the 50-yr storm event, per the County "Guidelines of Stormwater Management." The design approach is to perform the Powstring/SCS analysis for the 10-yr storm considering the on-site area only, along with the shorter time of concentration (Tc). Then perform the 50-yr analysis considering both the on-site and off-site areas combined, using the longer Tc (as appropriate for the larger drainage basin. Draw a comparison of the two, the larger volume requirements will be the controlling amount. Normally the contributing off-site area is analyzed using existing conditions. However, for Subbasin 'C', which is intended to be design for future conditions, the 10-yr storm for the entire subbasin will need to be considered as well. If you have any questions feel free to call me. M02 subbasin A: Whenever using QTR-55, multiply the basin area x 10 for data entry. This is because the flowrates generated are to the nearest integer. It is important to provided flowrates to at least + 0.1 cfs. Then by hydrograph multiplication, reduce the hydrograph to the correct amount. Please revise. DBr Provide level pool routing calculations for the pond in Subbasin 'A', which lists the max. water level achieved during the routing of the storm. DSubbasin C: T/id inage basin for future conditions change, per the calculation~learly show in the basin map what the limits of the basin 'W 11 be under future conditions. } Provide calculations demonstrating that the storm flow along the concrete curbs will not exceed 12' in width. Because the storm events need to be revised, the detailed review of the drainage calculations is not performed for this review. kVI'l jdr ~ 04 STORMWATER DRAINAGE CALCULATIONS FOR RIDGEMONT ESTATES NORTH 6TH ADDITION May 30. 1995 ' Prepared by: Simpson Engineers, Inc. North 909 Argonne Road Spokane, Washington 99212 TABLE OF CONTENTS 1. Summary RECEIVED JUN d 6 1995 SPOKANE COUNTY ENGWEER OFFICIAL PUBLIC [DOCUMENT SPOONE COUNTY ENGINEER'S OFFICE OR19,1 Pfi[7JEGT 1 N SUBMITTAL # z.P RETURN TO COUNTY ENGINEER II. 5tormwater Drainage Calculations for Basins A, B, and C of Ridgemont Estates North 6th Addition III. Attachments: * Soils Map and Tables Street and Drainage Plans. N Nlklo .WASL,- Stormwater Drainage Report; Ridgemont Estates North 6th Addition SUMMARY: The development is divided into three (3) basins; A, B, and C. See Drainage Map for Ridgemont Estates North 6th Addition. Each basin is composed of two subareas; 1) grass lawns, and 2) impervious roofs, driveways, and asphalt paved streets. 5tormwater flows overland across roots, grass lawns, and driveways and into grass drainage ponds. 5tormwater from asphalt streets flows along the curb gutters and into the grass drainage ponds through curb openings located at low points in the curb profile. The present drainage basin boundary for Basin A is shown an the drainage map. Basin A is primarily offsite with drainage flawing toward the plat. An earth berm will be constructed adjacent to the plat to intercept stormwater flowing onto the plat. St.ormwater will then pond up behind the berm and will percolate into the sail. The berm is temporary and will be removed when the adjacent unplatted portion of Ridgemont Estates North is platted and developed. Basins An and As are onsite, and the stormwater drainage facilities for these basins will be constructed on the plat. The drainage basin boundary for Basin C will change slightly as adjacent portions of Ridgemont Estates North are platted. The basin area will remain about the same size, but the impervious subarea will increase. Calculations for stormwater runoff were made for a present basin condition and a future condition. The future runoff condition for Basin C will require more dryweils and storage than the present runoff condition. Therefore, the drainage detention and discharge facilities along 5onara Street will be designed for the future runoff condition, since modifications to the pond would be undesirable in the future. The grass percolation areas (drainage ponds) were calculated to hold the first 1/2" of rainfall runoff over the asphalt street areas. Figure 2, page 6-3, of the "Guidelines for 5torrnwater Management", by Spokane County Engineers, was used for rainfall intensity and duration occurring at a 10-yea storm frequency for onsite drainage. The Rational and Bowstring Methods were used to calculate the peak storrnwater runoff for each basin, and the type and number of drywells needed for each basin based on the storage capacity of the pond. The S.C.S. QTR-55 method was used for calculating the stormwater runoff for Basin A. DIF-AINAGS C+~~~41LA~CiC7NS 5f~ _ ~S.l.'TE_.._.l.]N13~..Y_E[~oPEp....._~-0..-_~~,Gt~' -S"t~rw, _ • AgaA ToTAL. _AV>='.. 3ooil (1~'_~ r 5,6 0 V-f D.~(o Acre +1 _ _ _15 1 3 q, o_ F T . _ D_, Q S _ Ae F= - ~1a~r►ve_ i~Y+i-ti5vrn ~r~Ve.l 5t71~ IS ~aeP~bL~. o 0, _ 7~' - vvtc ~s ~q a~4 oga , _516,0$2--.i. ~I--°f-'Wgie-r -to e-'v 0A Did- cx J I I ~ I ` T ALA TTE. -N AO-00' t~ a d Gr o, y$ 5't'~v, d ca<r d ~ E ■ rz 038 $ 2-u-3ES ILO 'back z ~1 O-0Q' -1 I 8-.o .sa J )0+. r I ~ I ~ 1'. a7 I 1 Ff/S I E 1 P N 'l ~I 1 E ~~vtsruc~ Earth Berm ~ J ToIP of Berm El~v• 20 p° r r 3 _ I AVE. ^I F~1 9!1.01 To i i I f I i J 1 1 2317 W 125.00+ g M~ ~x ~ ~ a C~,r1~ nle-s, 1=e' 3a 00 ~a~~k ne C ~n Cur ~ ~ / T~nv r~ Et v 21 ~ g G.r 3nl , a and. aun ni I s~'rp 14-t rQ G'~d le C3arrel ~r~well~ 0~ clurb E~ l~ Pe B p --z ve.r ~ ~ s Y~ith Mewl V-ra,me. and Gtr 'ke'T e 4 pv~c ne C-O Awv,y Stvridox a Sto, 4A-05, 2.5 r i15 ht N Tod of Crake ~~ev Zo38I t 100.0006 $ o }t rn ~f Pond E lev 20 ~ - ~ F ui r 1 T. PC a -0 4- BA ~~c~ POND-2 Version: 5.15 SIN: 1295160123 Page 6 EXECUTED: 05-24-1995 11:27:45 SUMMARY OF ROUTING COMPUTATIONS Pond File: C:/PONDPACK/REN6 PND Inflow Hydrograph: C:\PONDPACK\REN6 HYD Outflow Hydrograph: C:\PONDPACK\REN6P HYD Starting Pond W.S. Elevation = 2038.00 ft Summary of Peak Outflow and Peak Elevation Peak Inflow e 7.10 cfs Peak Outflow - 0.23 cfs Peak Elevation = 2038.98 ft *****,Summary of Approximate Peak Storage Initial Storage 0 cu-ft Peak Storage From Storm = 11,315 cu-ft Total Storage in Pond 11,315 cu-ft POND-2 Version: 5.15 5/N: 1295160123 Pond File: C:\PONDPACK\REN6 Inflow Hydr©graph: C:`PONDPACK/REN6 Outflow Hydrogragh: C:\PONDPACK`REN6P Peak Inflow' = 7.10 cfs Peak outflow = 0.23 cfs Peak Elevation = 2038.98 ft 11.3 - 11.4 - 11.'5 - 11.6 - 11.7 - 11.8 - 11.9 - 12.0 - 12.1 - 12.2 - 12.3 - 12.4 - 12.5 - 12.6 - 12.7 - 12.8 - 12.9 - 13.0 - 13.1 - 13.2 - i TI1 (hi * Fj x Fj Page 7 . PAID .HYD .HYD EXECUTED: 05-24-1995 11:27:45 Flow (cfs) 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 11.0 x x x x x x x X* X X x x x x x x x x x x x x x x x X * x x x x x x x x x x * X X X [E `s ) le: C:\PONDPACK\REN6 .le: C:/PONDPACK♦REN6P * * * * * . HY,D Amax = 7.1 cf s .HYD Qmax = 0.2 cfs POND-2 Version: 5.15 SJN: 1295160123 Ridgemont Estates North 6th Addition CALCULATED 05-24-1995 11:08:18 DISK FILE: C:\PONDPACK`REN6 VOL Planimeter scale: 1 inch = 50 ft. Elevation Planimeter Area Al+A2+sgr(A1*A2) Volume Volume Sum (ft) (sq.in.) (sq.ft) (sq.ft) (cubic-ft) (Cubic-ft) - 2,038.00 0.41 1,025 0 0 0 2,039.00 11.30 28,250 34,656 11,552 11,552 2,040.00 25.21 63,025 133,470 44,490 56,042 * Incremental volume computed by the Conic Method for Reservoir Volumes. POND-2 Version: 5.15 SIN: 1295160123 EXECUTED: 05-24-1995 11:27:45 Page 1 * Ridgemont Estates North 6th Addition * soil outflow = 0.36 in./hr. per sq.ft. (value for sod) * = 0.00000833 cfs per sq.ft. * * Inflow Hydrograph: C:\PONDPACK`REN6 Rating Table file: C:\PONDPACK\REN6 ----INITIAL CONDITIONS---- Elevation = 2038.00 ft Outflow = 0.01 cfs Storage = 0 cu-ft GIVEN POND DATA ELEVATION OUTFLOW STORAGE (ft) (cfs) (cu-ft) 2038.00 0.0 0 2039.00 0.2 11,552 2040.00 0.5 56,042 .HYD .PND INTERMEDIATE ROUTING COMPUTA'T'IONS 2S/t 2S/t + 0 (Cfs) (cfs) 0.0 0.0 64.2 64.4 311.3 311.9 Time increment (t) = 0.100 hrs. POND-2 Version: 5.15 SIN: 1295160123 EXECUTED: 05-24-1995 11:27:45 Pond File: C:/PONDPACK\REN6 PND Inflow Hydrograph: C:`PONDPACKIREN6 HYD Outflow Hydrograph: C:/PONDPACK/REN6P HYD INFLOW HYDROGRAPH ROUTING COMPUTATIONS Page 2 TIME INFLOW Il+I2 2S/t - 0 2S/t. + 0 OUTFLOW ELEVATION (hrs) (cfs) (cfs) (cfs) (cfs) (cfs) (ft) 11.000 0.00 -0.0 0.0 0.01 2038.00 11.100 0.00 0.0 -0.0 -0.0 0.00 2038.00 11.200 0.00 0.0 -0.0 -0.0 0.00 2038.00 11.300 0.00 0.0 -0.0 -0.0 0.00 2038.00 11.400 0.00 0.0 -0.0 -0.0 0.00 2038.00 11.500 0.00 0.0 -0.0 -0.0 0.00 2038.00 11.600 0.00 0.0 --0.0 -0.0 0.00 2038.00 11.700 0.40 0.4 0.4 0.4 0.01 2038.01 11.800 0.70 1.1 1.4 1.5 0.01 2038.02 11.900 1.10 1.8 3.2 3.2 0.02 2038.05 12.000 4.00 5.1 8.2 8.3 0.04 2038.13 12.100 ~o 7.10 11.1 19.2 19.3 0.08 2038.30 12.200 4.10 11.2 30.1 30,4 0.12 2038.47 12.300 1.70 5.8 35.7 35.9 0.14 2038.56 12.400 1.40 3.1 38.5 38.8 0.15 2038.60 12.500 1.20 2.6 40.8 41.1 0.15 2038.64 12.600 1.00 2.2 42.7 43.0 0.16 2038.67 12.700 0.90 1.9 44.2 44.6 0.17 2038.69 12.800 0.80 1.7 45.6 45.9 0.17 2038.71 12.900 0.80 1.6 46.8 47.2 0.17 2038.73 13.000 0.70 1.5 48.0 48.3 0.18 2038.75 13.100 0.60 1.3 48.9 49.3 0.18 2038.76 13.200 0.60 1.2 49.7 50.1 0.18 2038.78 13.300 0.60 1.2 50.6 50.9 0.19 2038.79 13.400 0.50 1.2 51.4 51.8 0.19 2038.80 13.500 0.60 1.2 52.2 52.6 0.19 2038.82 13.600 0.50 1.1 52.9 53.3 0.20 2038.83 13.700 0.50 1.0 53.5 53.9 0.20 2038.84 13.800 0.50 1.0 54.1 54.5 0.20 2038.85 13.900 0.40 0.9 54.6 55.0 0.20 2038.85 14.000 0.40 0.8 55.0 55,4 0.20 2038.86 14.100 0.40 0.8 55.4 55.8 0.20 2038.87 14.200 0.40 0.8 55.8 56.2 0.21 2038.87 14.300 0.40 0.8 56.2 56.6 0.21 2038.88 14.400 0.40 0.8 56.5 57.0 0.21 2038.88 14.500 0.40 0.8 56.9 57.3 0.21 2038.89 14.600 0.40 0.8 57.3 57.7 0.21 2038.90 14.700 4.40 0.8 57.7 58.1 0.21 2038.90 14.800 0.40 0.8 58.0 58.5 0.21 2038.91 14.900 0.40 0.8 58.4 58.8 0.22 2038.91 15.000 0.40 0.8 58.8 59.2 0.22 2038.92 15.100 0.40 0.8 59.1 59.6 0.22 2038.93 15.200 0.40 0.8 59.5 59.9 0.22 2038.93 15.300 0.30 0.7 59.8 60.2 0.22 2038.93 15.400 0.30 0.6 59.9 60.4 0.22 2038.94 POND-2 Version: 5.15 S/N: 1295160123 EXECUTED: 05-24-1995 11:27:45 Pond File: C:IPONDPACK\REN6 PND Inflow Hydrograph: C:/PONDPACK/REN6 HYD Outflow Hydrograph: C:/PONDPACK/REN6P HYD INFLOW HYDROGRAPH Page 3 ROUTING COMPUTATIONS TIME INFLOW I1+I2 2S/t - O 2S/t + O OUTFLOW ELEVATION (hrs) (cfs) (cfs) (cfs) (cfs) (cfs) (ft) 15,500 0.30 0.6 60.1 60.5 0.22 2038.94 15.600 0.30 0.6 60.2 60.7 0.22 2038,94 15.700 0.30 0.6 60.4 60.8 0.22 2038.94 15.800 0.30 0.6 60.5 61.0 0.22 2038.95 15.900 0.30 0.6 60.7 61.1 0.22 2038.95 16.000 0.30 0.6 60.9 61.3 0.22 2038.95 16.100 0.30 0.6 61.0 61.5 0.22 2038.95 16.200 0.30 0.6 61.2 61.6 0.23 2038.96 16.300 0.30 0.6 61.3 61.8 0.23 2038.96 16,400 0.30 0,6 61.5 61.9 0.23 2038.96 16.500 0.30 0.6 61.6 62.1 0.23 2038.96 16.600 0.30 0.6 61.7 62.2 0.23 2038.97 16.700 0.30 0.6 61.9 62.3 0.23 2038.97 16.800 0.30 0.5 62.0 62.5 0.23 2038.97 16.900 0.30 0.6 62,2 62.6 0,23 2038.97 17.000 0.30 0.6 62.3 62.8 0.23 2038.97 17.100 0.30 0.6 62.5 62.9 0.23 2038.98 17.200 0.30 0.6 62.6 63.1 0.23 2038.98 17.300 0.20 0.5 62.6 63.1 0.23 2038.98 17.400 0.20 0.4 62.6 63.0 0.23 2038.98 17.500 0.20 0.4 62.5 63.0 0.23 2038.98 17.600 0.20 0.4 62.5 62.9 0.23 2038.98 17.700 0.20 0.4 62.4 62.9 0.23 2038.98 17.800 0.20 0.4 62,3 62.8 0.23 2038,97 17.900 0.20 0.4 62.3 62.7 0.23 2038.97 18.000 0.20 0.4 62.2 62.7 0.23 2038.97 18.100 0,20 0.4 62,2 62.6 0.23 2038.97 18.200 0.20 0.4 62.1 62.6 0.23 2038.97 18.300 0.20 0,4 62.1 62.5 0.23 2038.97 18.400 0.20 0.4 62.0 62.5 0.23 2038.97 18.500 0.20 0.4 61.9 62.4 0.23 2038.97 18.600 0.20 0.4 61.9 62.3 0.23 2038.97 18.700 0.20 0.4 61.8 62.3 0.23 2038,97 18.800 0.20 0.4 61.8 62.2 0.23 2038.97 18.900 0.20 0.4 61.7 62.2 0.23 2038.97 19.000 0.20 0.4 61,7 62.1 0,23 2038.96 19.104 0.20 0.4 61.6 62.1 0.23 2038.96 19.200 0.20 0.4 61.6 62.0 0.23 2038.96 19.300 0,20 0.4 61.5 62.0 0.23 2038.96 19.400 0.20 0.4 61.5 61.9 0.23 2038.96 19.500 0.20 0.4 61.4 61.9 0.23 2038.96 19.600 0.20 0.4 61.3 61.8 0.23 2038.96 19.700 0.20 0.4 61.3 61.7 0.23 2038.96 19.800 0.20 0.4 61.2 61.7 0.23 2038.96 19.900 0.20 0.4 51.2 61.6 0.23 2038.96 20,000 0.20 0.4 61.1 61.6 0.23 2038.96 i POND-2 Version: 5.15 SIN: 1295160123 EXECUTED: 05-24-1995 11:27:45 Pond File: C:IPONDPACK/REN6 PND Inflow Hydrograph: C:OPONDPACK/REN6 HYD Outflow Hydrograph: C:\PONnPACK\REN6P HYD INFLOW HYDROGRAPH Page 4 ROUTING COMPUTATIONS TIME INFLOW I1+12 2S/t - O 2S/t + 0 OUTFLOW ELEVATION (hrs) (cfs) (cfs) (cfs) (cfs) (cfs) (ft) 20.100 0.20 0.4 61.1 61.5 0.22 2038.96 20.200 0.20 0.4 61.0 61.5 0.22 2038.95 20.300 0.20 0.4 61.0 61.4 0.22 2038.95 20.400 0.20 0.4 60.9 61.4 0.22 2038.95 20.500 0.20 0.4 60.9 '61.3 0.22 2038.95 20.600 0.20 0.4 60.9 61.3 0.22 2038.95 20.700 0.20 0.4 60.8 61.3 0.22 2038.95 20.8010 0.20 0.4 60.8 61.2 0.22 2038.95 20.900 0.20 0.4 60.7 61.2 0.22 2038.95 21.000 0.20 0.4 60.7 61.1 0.22 2038.95 21.100 0.20 0.4 60.6 61.1 0.22 2038.95 21.200 0.20 0.4 60.6 61.0 0.22 2038.95 21.300 0.207 0.4 60.5 61.0 0.22 2038.95 21.400 0.20 0.4 60.5 60.9 0.22 2038.95 21.500 0.20 0.4 60.4 60.9 0.22 2038.95 21.600 0.20 0.4 60.4 60.8 0.22 2038.94 21.700 0.20 0.4 60.3 60.8 0.22 2038.94 21.800 0.20 0.4 60.3 60.7 0.22 2038.94 21.900 0.20 0.4 60.3 60.7 0.22 2038.94 22.000 0.20 0.4 60.2 60.7 0.22 2038.94 22.100 0.20 0.4 60.2 60.6 0.22 2038.94 22.200 0.20 0.4 60.1 60.6 0.22 2038.94 22.300 4.20 0.4 60.1 60.5 0.22 2038.94 22.400 0.20 0.4 60.0 60.5 0.22 2038.94 22.500 0.20 0.4 60.0 60.4 0.22 2038.94 22.600 0.20 0.4 60.0 60.4 0.22 -2038.94 22.700 0.20 0.4 59.9 60.4 0.22 2038.94 22.800 0.20 0.4 59.9 60.3 0.22 2038.94 22.900 0.20 0.4 59.8 60.3 0.22 2038.94 23.000 0.20 0.4 59.8 60.2 0.22 2038.94 23.100 0.10 0.3 59.7 +60.1 0.22 2038.93 23.200 0.10 0.2 59.4 59.9 0.22 2038.93 23.300 0.10 0.2 59.2 59.6 0.22 2038.93 23.400 0.10 0.2 58.9 59.4 0.22 2038.92 23.500 0.10 0.2 58.7 59.1 0.22 2038.92 23.600 0.10 0.2 58.5 58.9 0.22 2038.91 23.700 0.10 0.2 58.2 58.7 0.21 2038.91 23.800 0.10 0.2 58.0 58.4 0.21 2038.91 23.900 0.10 0.2 57.8 58.2 0.21 2038.90 24.000 0.10 0.2 57.6 58.0 0.21 2038.90 24.100 0.10 0.2 57.3 57.8 0.21 2038.90 24.200 0.10 0.2 57.1 57.5 0.21 2038.89 24.300 0.10 0.2 56.9 57.3 0.21 2038.89 24.400 0.10 0.2 56.7 57.1 0.21 2038.89 24.500 0.10 0.2 56.5 56.9 0.21 2038.88 24.600 0.10 0.2 56.3 56.7 0.21 2038.88 POND-2 Version: 5.15 SIN: 1295160123 EXECUTED: 05-24-1995 11:27:45 Pond File: C:\PONDPACK\REN6 PND Inflow Hydrograph: C:\PONDPACK\REN6 HYD Outflow Hydrograph: C:\PONDPACK\REN6P HYD INFLOW HYDROGRAPH TIME INFLOW (hrs) (cfs) 24.700 0.10 24.800 0.10 24.900 0.10 25.000 0.00 25.100 0.00 25.200 0.00 25.300 0.00 25.400 0.00 25.500 0.00 25.600 0.00 25.700 0.00 25.800 0.00 25.900 0.00 ROUTING COMPUTATIONS Page 5 I1+I2 2S/t - 0 2S/t + 0 OUTFLOW ELEVATION (cfs) (cfs) (cfs) (cfs) (ft) 0.2 56.0 56.5 0.21 2038.88 0.2 55.8 56.2 0.21 2038.87 0.2 55.6 56.0 0.21 2038.87 0.1 55.3 55.7 0.20 2038.86 0.0 54.9 55.3 0.20 2038.86 0.0 54.5 54.9 0.20 2038.85 0.0 54.1 54.5 0.20 2038.85 0.0 53.7 54.1 0.20 2038.84 0.0 53.3 53.7 0.20 2038.83 0.0 52.9 53.3 0.20 2038.83 0.0 52.5 52.9 0.19 2038.82 0.0 52.1 52.5 0.19 2038.82 0.0 51.8 52.1 0.19 2038.81 POND-2 Version: 5.15 SIN: 1295160123 Page 1 Executed 05-24-1995 09:53:15 Multiply Hydrograph by Constant Unit HYD File: C:\PONDPACK\REN6Xl0.HYD Output Hydrograph: C:/PONDPACK\REN6 HYD Multiplier Constant: .1 TIME Unit Multiplier Output Hydrograph (hrs) ordinates Constant (cfs) 11.00 0.00 x 0.100 = 0.00 11.10 0.00 x 0.100 - 0.00 11.20 0.00 x 0.100 - 0.00 11.30 0.00 x 0.100 = 0.00 11.40 0.00 x 0.100 = 0.00 11.50 0.00 x 0.100 - 0.00 11.60 0.00 x 0.100 0.00 11.70 4.00 x 0.100 = 0.40 11.80 7.00 x 0.100 - 0.70 11.90 11.00 x 0.100 = 1.10 12.00 40.00 x 0.100 - 4.00 12.10 71.00 x 0.100 = 7.10 12.20 41.00 x 0.100 4.10 12.30 17.00 x 0.100 = 1.70 12.40 14.00 x 0.100 - 1.40 12.50 12.00 x 0.100 - 1.20 12.60 10.00 x 0.100 = 1.00 12.70 9.00 x 0.100 = 0.90 12.80 8.00 x 0.100 - 0.80 12.90 8.00 x 0.100 = 0.80 13.00 7.00 x 0.100 = 0.70 13.10 6.00 x 0.100 - 0.60 13.20 6.00 x 0.100 = 0.60 13.30 6.00 x 0.100 - 0.60 13.40 6.00 x 0.100 = 0.60 13.50 6.00 x 0.100 - 0.60 13.60 5.00 x 0.100 = 0.50 13.70 5.40 x 0.100 = 0.50 13.80 5.00 x 0.100 = 0.50 13.90 4.00 x 0.100 - 0.40 14.00 4.00 x 0.100 = 0.40 14.10 4.00 x 0.100 = 0.40 14.20 4.00 x 0.100 = 0.40 14.30 4.00 x 0.100 - 0.40 14.40 4.00 x 0.100 - 0.40 14.50 4.00 x 0.100 0.40 14.60 4.00 x 0.100 = 0.40 14.70 4.00 x 0.100 - 0.40 14.80 4.00 x 0.100 - 0.40 14.90 4.00 x 0.100 0.40 15.00 4.00 x 0.100 = 0.40 15.10 4.00 x 0.100 - 0.40 POND-2 Version: 5.15 SIN: 1295160123 Executed 05-24-1995 09:53:15 Page 2 Multiply Hydrograph by Constant Unit HYD File: C:`PONDPACK\REN6X10.HYD Output Hydrograph: C:\PONDPACK\REN6 .HYD Multiplier Constant: .1 4 I TIME Unit Multiplier Output Hydrograph (hrs) Ordinates - - - Constant (cfs) 15.20 - - 4.00 x 0.100 - 0.40 15.30 3.00 x 0.100 = 0.30 15.40 3.00 x 0.100 = 0.30 15.50 3.00 x 0.100 - 0.30 15.60 3.00 x 0.100 = 0.30 15.70 3.00 x 0.100 = 0.30 15.80 3.00 x 0.100 - 0.30 15.90 3.00 x 0.100 = 0.30 16.00 3.00 x 0.100 = 0.30 16.10 3.00 x 0.100 - 0.30 16.20 3.00 x 0.100 - 0.30 16.30 3.00 x 0.100 = 0.30 16.40 3.00 x 0.100 = 0.30 16.50 3.00 x 0.100 = 0.30 16.60 3.00 x 0.100 = 0.30 16.70 3.00 x 0.100 0.30 16.80 3.00 x 0.100 - 0.30 16.90 3.00 x 0.100 - 0.30 17.00 3.00 X 0.100 = 0.30 17.10 3.00 x 0.100 - 0.30 17.20 3.00 x 0.100 = 0.30 17.30 2.00 x 0.100 = 0.20 17.40 2.00 x 0.100 - 0.20 17.50 2.00 x 0.100 = 0.20 17.60 2.00 x 0.100 - 0.20 17.70 2.00 x 0.100 0.20 17.80 2.00 X 0.100 = 0.20 17.90 2.00 x 0.100 = 0.20 18.00 2.00 x 0.100 = 0.20 18.10 2.00 x 0.100 = 0.20 18.20 2.00 x 0.100 = 0.20 18.30 2.00 X. 0.100 = 0.20 18.40 2.00 x 0.100 = 0.20 18.50 2.00 x 0.100 - 0.20 18.60 2.00 x 0.100 - 0.20 18.70 2.00 x 0.100 - 0.20 18.80 2.00 x 0.100 = 0.20 18.90 2.00 x 0.100 - 0.20 19.00 2.00 X 0.100 = 0.20 19.10 2.00 x 0.100 = 0.20 19.20 2.00 x 0.100 - 0.20 POND-2 Version: 5.15 SIN: 1295160123 Executed 05-24-1995 09:53:15 Page 3 Multiply Hydrograph by Constant Unit HYD File: C:\PONDPACK\REN6X1o.HYd Output Hydrograph: C:/PONDPACK/REN6 HYD Multiplier Constant: .1 TIME Unit Multiplier Output Hydrograph (hrs) Ordinates Constant (cfs) - 19.30 2.00 x 0.100 - 0.20 19.40 2.00 x 0.100 - 0.20 19.50 2.00 x 0.100 - 0.20 19.60 2.00 x 0.100 = 0.20 19.70 2.00" x 0.100 = 0.20 19.80 2.00 x 0.100 = 0.20 19.90 2.00 x 0.100 - 0.20 20.00 2.00 x 0.100 = 0.20 20.10 2.00 x 0.100 0.20 20.20 2.00 x 0.100 - 0.20 20.30 2.00 x 0.100 = 0.20 20.40 2.00 x 0.100 = 0.20 20.50 2.00 x 0.100 0.20 20.60 2.00 x 0.100 - 0.20 20.70 2.00 x 0.100 = 0.20 20.80 2.00 x 0.100 0.20 20.90 2.00 x 0.100 - 0.20 21.00 2.00 x 0.100 - 0.20 21.10 2.00 x 0.100 - 0.20 21.20 2.00 x 0.100 = 0.20 21.30 2.00 x 0.100 = 0.20 21.40 2.00 x 0.100 = 0.20 21.50 2.00 x 0.100 - 0.20 21.60 2.00 x 0.100 = 0.20' 21.70 2.00 x 0.100 = 0.20 21.80 2.00 x 0.100 - 0.20 21.90 2.00 x 0.100 = 0.20 22.00 2.00 x 0.100 = 0.20 22.10 2.00 x 0.100 - 0.20 22.20 2.00 x 0.100 - 0.20 22.30 2.00 x 0.100 = 0.20 22.40 2.00 x 0.100 = 0.20 22.50 2.00 x 0.100 = 0.20 22.60 2.00 x 0.100 0.20 22.70 2.00 x 0.100 = 0.20 22.80 2.00 x 0.100 = 0.20 22.90 2.00 x 0.100 0.20 23.00 2.00 x 0.100 = 0.20 23.10 1.00 x 0.100 = 0.10 23.20 1.00 x 0.100 0.10 23.30 1.00 x 0.100 = 0.10 POND-2 Version: 5.15 SIN: 1295160123 Executed 05-24-1995 09:53:15 Page 4 Multiply Hydrograph by Constant Unit HYD File: C:\PONDPACK\REN6X10.HYD Output Hydrograph: C:\PONDPACK\REN6 HYD Multiplier Constant: .1 TIME Unit Multiplier Output Hydrograph (hrs) Ordinates Constant (cfs) 23.40 1.00 x 0.100 = 0.10 23.50 1.00 x 0.100 = 0.10 23.60 1.00 x 0.100 = 0.10 23.70 1.00 x 0.100 = 0.10 23.80 1.00 x 0.100 = 0.10 23.90 1.00 x 0.100 = 0.10 24.00 1.00 x 0.100 = 0.10 24.10 1.00 x 0.100 = 0.10 24.20 1.00 x 0.100 = 0.10 24.30 1.00 x 0.100 = 0.10 24.40 1.00 x 0.100 = 0.10 24.50 1.00 x 0.100 = 0.10 24.60 1.00 x 0.100 = 0.10 24.70 1.00 x 0.100 = 0.10 24.80 1.00 x 0.100 = 0.10 24.90 1.00 x 0.100 = 0.10 25.00 0.00 x 0.100 = 0.00 25.10 0.00 x 0.100 = 0.00 25.20 0.00 x 0.100 = 0.00 25.30 0.00 x 0.100 = 0.00 25.40 0.00 x 0.100 = 0.00 25.50 0.00 x 0.100 = 0.00 25.60 0.00 x 0.100 = 0.00 25.70 0.00 x 0.100 = 0.00 25.80 0.00 x 0.100 = 0.00 25.90 0.00 x 0.100 = 0.00 Quick TR-55 Version: 5.45 SIN: 1315460151 Page 1 Return Frequency: 50 years TR-55 TABULAR HYDROGRAPH METHOD Type II. Distribution (24 hr. Duration Storm) Executed: 05-24-1995 09:48:51 Watershed file: C:\PONDPACK\REN6 MOP Hydrograph file: C:\PONDPACK\REN6X10.HYD Ridgemont Estates North 6th Addition Input Parameters Used to Compute Hydrograph Subarea AREA CN Tc * Tt Precip. Runoff Ia/p Description (acres) (hrs) (hrs) I (in) (in) input/used Basin A @ 10x 104.40 70.0 0.10 0.00 - 2.60 0.50 1.33 .33 * Travel time from subarea outfall to composite watershed outfall point. I Subarea where user specified interpolation between Ia/p tables. Total area = 104.40 acres or 0.1631 sq.mi Peak discharge = 71 cfs Computer Modifications of Input Parameters Input Values Rounded Values Ia/p Subarea Tc * Tt Tc * Tt Interpolated Ia/p Description (hr) (hr) (hr) (hr) (Yes/No) Messages Basin A @ 10x 0.10 0.00 Yes * Travel time from subarea outfall to composite watershed outfall point. Tc & Tt are available in the hydrograph tables. Quick TR-55 Version: 5.45 SIN: 1315460151 Page 2 Return Frequency: 50 years TR-55 TABULAR HYDROGRAPH METHOD Type II. Distribution (24 hr. Duration Storm) Executed: 05-24-1995 09:48:51 Watershed tile: C:/PONDPACK/REN6 MOP Hydrograph file: C:\PONDPACK\REN6X10.HYD Ridgemont Estates North 6th Addition ]>33 Summary of Subarea Times to Peak c<<< Subarea Basin A @ 1Dx Composite Watershed Peak Discharge at Composite Dutfall (cfs) 71 71 Time to Peak at Composite outfall (hrs) 12.1 12.1 Quick TR-55 Version: 5.45 5/N: 1315460151 Page 3 Return Frequency: 50 years TR-55 TABULAR HYDROGRAPH METHOD Type II. Distribution (24 hr. Duration Storm) Executed: 05-24-1995 09:48:51 Watershed file: C : \PONDPACK\REN6 . MOP Hydrograph file: C:\PONDPACK\REN6XID.HYD Ridgemont Estates North 6th Addition Composite Hydrograph Summary (cfs) Subarea 11.0 11.3 11.6 11.9 12.0 12.1 12.2 12.3 12.4 Description hr hr hr hr hr hr hr - hr hr Basin A @ 10x 0 0 0 11 40 71 41 17 14 Total (cfs) 0 0 0 11 40 71 41 17 14 Subarea 12.5 12.6 12.7 12.8 13.0 13.2 13.4 13.6 13.8 Description hr hr fir hr hr hr hr hr hr Basin A@ 10x 12 10 9 8 7 6 6 5 5 Total (cfs) 12 10 9 8 7 6 6 5 5 Subarea 14.0 14.3 14.6 15.0 15.5 16.0 16.5 17.0 17.5 Description hr hr hr hr hr hr hr hr hr Basin A@ 10x 4 4 4 4 3 - 3 - 3 - 3 2 Total (cfs) 4 4 4 - 4 - 3 - 3 3 3 2 Subarea 18.0 19.0 20.0 22.0 26.0 Description hr hr hr hr hr Basin A@ lox 2 2 2 2 0 Total (cfs) 2 2 2 2 0 Quick TR-55 Version: 5.45 S/N: 1315460151 Page 4 Return Frequency: 50 years TR-55 TABULAR HYDROGRAPH METHOD Type II. Distribution (24 hr. Duration Storm) Executed: 05-24•-1995 09:48:51 Watershed file: C:1.P0NDPACK/REN6 MOP Hydrograph file: C:/P0NDPACK\REN6X10.HYD Ridgemont Estates North 6th Addition Time Flow Time Flow (hrs) (cfs) (hrs) (cfs) 11.0 0 14.8 4 11.1 0 14.9 4 11.2 0 15.0 4 11.3 0 15.1 4 11.4 0 15.2 4 11.5 0 15.3 3 11.6 0 15.4 3 11.7 4 15.5 3 11.8 7 15.6 3 11.9 11 15.7 3 12.0 40 15.8 3 12.1 71 15.9 3 12.2 41 16.0 3 12.3 17 16.1 3 12.4 14 16.2 3 12.5 12 16.3 3 12.6 10 16.4 3 12.7 9 16.5 3 12.8 8 16.6 3 12.9 8 16.7 3 13.0 7 16.8 3 13.1 6 16.9 3 13.2 6 17.0 3 13.3 6 17.1 3 13.4 6 17.2 3 13.5 6 17.3 2 13.6 5 17.4 2 13.7 5 17.5 2 13.8 5 17.6 2 13.9 4 17.7 2 14.0 4 17.8 2 14.1 4 17.9 2 14.2 4 18.0 2 14.3 4 18.1 2 14.4 4 18.2 2 - 14.5 4 18.3 2 14.6 4 18.4 2 14.7 4 18.5 2 Quick TR-55 Version: 5.45 SIN: 1315460151 Page 5 Return Frequency: 50 years TR-55 TABULAR HYDROGRAPH METHOD Type II. Distribution (24 hr. Duration Storm) Executed: 05-24-1995 09:48:51 Watershed file: C:\PONDPACK\REN6 MOP Hydrograph file: C:\PONDPACK\REN6X10.HYD Ridgemont Estates North 6th Addition Time Flow Time Flow (hrs) (cfs) (hrs) (cfs) 18.6 2 22.4 2 18.7 2 22.5 2 18.8 2 22.6 2 18.9 2 22.7 2 19.0 2 22.8 2 19.1 2 22.9 2 19.2 2 23.0 2 19.3 2 23.1 1 19.4 2 23.2 1 19.5 2 23.3 1 19.6 2 23.4 1 19.7 2 23.5 1 19.8 2 23.6 1 19.9 2 23.7 1 20.0 2 23.8 1 20.1 2 23.9 1 20.2 2 24.0 1 20.3 2 24.1 1 20.4 2 24.2 1 20.5 2 24.3 1 20.6 2 24.4 1 20.7 2 24.5 1 20.8 2 24.6 1 20.9 2 24.7 1 21.0 2 24.8 1 21.1 2 24.9 1 21.2 2 25.0 0 21.3 2 25.1 0 21.4 2 25.2 0 21.5 2 25.3 0 21.6 2 25.4 0 21.7 2 25.5 0 21.8 2 25.6 0 21.9 2 25.7 0 22.0 2 25.8 0 22.1 2 25.9 0 22.2 2 22.3 2 Quick TR-55 Ver.5.45 S/N:1315460151 Executed: 09:47:08 05-24-1995 'Ridgemont Estates North 6th Addition RUNOFF CURVE NUMBER SUMMARY Subarea Area CN Description -(acres) (weighted) Basin A @ 10x 104.40 70 Quick TR-55 Ver.5.45 s/N:1315460151 Executed: 09:47:08 05-24-1995 Ridgemont Estates North 6th Addition RUNOFF CURVE NUMBER DATA Composite Area: Basin A @ 10x AREA CN SURFACE DESCRIPTION (acres) pavt. 3.60 98 grass 100.80 69 COMPOSITE AREA 104.40 70.0 ( 70 } ~U)6~MOMT {,STKTGS ~ gr-IR a~H AL)I) TJmIA Yad. IZ'1~ I oil - 5 j4\F. rc: A FIT . , A C r= rt ®~A1. A ekV T. LoT.5 @ 2-c)02 10 U?kVE5 L-O-T 'P` 6 7-AS5 - &0 315 38f 6 8~ fT.~ 0.~'~ AC~~ ~v~7GEh'~aNT ~SrtrA"~~~ i~alzTt~ c®Y~ ~~~~~fv~ v A~~ t eCaul RF.e - l~ -dear .s~`orr„ fy4. 12~~ ~ ~r,3 4WSr►'~` ~_.C. Yr• f.Y.~ - p~ub~earr e~7rwel~ ID c 4.y A-r 5I 1D E PF-ZvIDe ~ 2 S. 4 0 La 2.D b 3f LK rr' fl "f 2'ir 2"L+ 2 11 t a I z9 RATIONAL FURMULA HYDRDLE)BY DATE = 4/24195 DESISNER = K W MCMULKIN BASIN "A" Vk PROJECT !TAME = 1=t. E . NORTH 6TH ADDITION DESCR I F'T I ON - STORMW(wTER DRAINAGE SUBAREA 1 = .49 ACHES SUBAREA I RUNOFF COEFFICIENT .9 SUBAREA 2 = .89 ACRES SUBAREA 2 RUNOFF COEFFICIENT = .1C TOTAL AREA = 1..38 ACRES comr'OS L -rE RUNOFF COEFFICIENT = . 416; [=s4:7~47026 OVERLAND FLOW VALUES ct - 1S N _ .4 S - .01 CHANNEL FLOW VALUES L - .11 Z1 = .172 Z2 = --",6 N .016 D - S = .026 TD .1836 COMPUTED VALUES DUR - 5. 00 T10 = w+.1e 01 0 = 1 g CA - 1 8 , B OWSTRING CALCULATIONS DATE = 4/24/95 DES IGNER = h, W MCMUL4` IN BASIN "A`1 PROJECT NAME ~ R.E. 1413RTFI 6TH ADDITION DESCRIPTION - 5TORMWATER DRA I N ;AGE t t Intens:L Ly Odev. VSn Vora storage' Orin. 3 (Ser- (in. /hr. (CU. ft. 3 (CU. ft.) (CL(. ft. 3 5,~► c.] C1 . I E4 1.43 , 77~4 4-34 10. 0 600 '22. 2 4 1.29 9C 1 600) 0: 15. 0 900 1.77 1 . 02 1019 900 119 20. 0 1200 1 . 45 .8--, , 10185 1200 -1 15 25.0 1500 1.21 .70 1114 1500 -~;E)6 0. 0 1800 1.04 .61) 117-', h 1800 -664 :5. 0 ~ I oc_1 .91 . 5E 1 151 y 1 C1 C1 --949 40.0 2400 . 82 .47 1179 2400 -1221 45. (=1 2700 .74 . 4~--, 1191, W2700 -1509 50.0 SOOO . 68 .39 1212 w c.)Q 0 -1788 55.0 3 :'00 .64 . ::~17 1251 -2049 60. 0 x,600 .61 . ,~5 1297 r•60Cj -271 0 65. 0 3-90C1 . 60 3 4 I ~•6G 3900 215- 2 70.0 4200 .58 1 42, 0 0 -2767 7.5. 0 45c:10 .56 1467 4500 ~yCsG~a 8C1. C1 4800 . 5: . YO 1497, 4800 ,C1T 85.0 510C1 .52 .30 15:9 51 C1 C1 r~ - X61 90.0 5400 .50 .29 15801 5400 821 C1 95.0 5700 .49 .213 16::~:; 5700 -4067 1 GO. 0 6000 . 48 .28 160:. 600101 "-4i• 17 THE MAXIMUM STORAGE 1S 474.41703-' CLL. FT. 4 The time of concentration is 5 mz nates. The Undevelo ped f I ow out a s 1 c. f. s. TEN YEAR STORM CALC .l rte/ RAT IO14AL FORMULA HYDROLOGY DATE = 4/24/95 DES IONER = K W MCMULK 114 BASIN "All PROJECT NAME = R.E. NORTH 6TH ADD1T1ON DESCRIPTION = F'AVT. SUBAREA 1 = .49 ACRES SUBAREA 1 RUNOFF COEFFICIENT = .9 TOTAL. AREA = .49 ACHES compOS T TE RUNOl= F" COEI=F I L I t NT .9 OVERLAND FLOW VALUES Ct = .15 L -=a N = .4 S ()I CHANNEL FLOW VALUES L = 315 Z l = .172 Z2 = 36 N = .016 H 0 S - -a'-16 TD = .166 COMPUTED VALUES DUR = 5. 00 110 = 3.18 010 = 1.40 QA = 1.40 ~~rb Dpenih3 ph C.Dv1';{ inu0 5 GYrL~e wzw m cwt g ~J+c-r o, ~Cor Sir or-v~w~'~er Nl~ha~~mea~n~ i i a_ I [DEPTH OF FLOW - y w FEET 0 .1<64~ AI .02 .03 .04 ,03 .06 .00 .10 2 4 e 3 8 7 8 9 10 1 I 4 11 Id r •I ~ ~ k I ---1- ~ t -4- t I _L_L I ' F1 1, I ~ C 1 I 1 1 i C I I~ 1 1 1 I l~ lk'~' I I I I I I 1I I f I Cl I" I p r I I I ~ I I 1 f I I; ~ I I . I p C I I I I k 11 I.I I 1 1 9 I I I f I I . I I I i j i f I ! I f I I I,ii ~ I I I I 4 I y l I I I I C I 11 I I I (a) DISCHARGE PER FOOT OF LENGTH OF CURB OPENING INLETS WHEN INTERCEPTING 100% OF GLITTER FLOW (b) PARTIAL INTERCEPTION RATIO FOR INLETS OF LENGTH LESS THAN L' 1.0 .a .6 8 .4 .3 .2 , Q~ La !10 D•105 oa 06 .0S .04 i .03 .02 i t k I I t f I 3 I I ~ ± I I I ~ryo I L i I I i I I' I 1 t i I I I 1 I 0 4 O Qa 3 .09 06 06 10 - 2 3 ,4 5 s a 10 L/L,a CAPACITY OF CURB OPENING INLETS ON CONTINUOUS GRADE 6-39 FIGURE 16 ~~ASNA CA,l.CUL,k-T1014s ~wm +~S t N A - X11- try : l ~ Z t+_rnn Zoe- I FT. 3 Y -y;l 01,14 rir,c~ ~ - ~ fT ~ ~ ~ ~ a+~~le. ~pcxrr~~ DryWe~l ~FtAG Ei iv e-os-t 4>> XL zs- RATIONAL FORMULA H` DR'OLOGY DATE = ~~95 DESIGNER = I ; W 1'lCNULi' 1N f~AS I fd ' F,5 PROJECT NAME = R.E. NORTH 6TH ADDITION DESCRIPTION = STORNWATER DRAINAGE cnumHRL- A I = .04 ACRES SUBAREA I RUNOFF COEF rF I C I ENT = SUBAREA 2=.07 ACRES SUBAREA C RUNOI'F COEFFICIENT = TOTAL AREA = . 1 1 ACRES COMPOSITE RUNOFF COEFFICIENT = OVERLAND FLOW VALUES Ct _ .15 L = 0 ` N = .016 S .01 CHANINEL FLAW VALUES L 95 Z1 = .172 Z2 = 7.6 N .016 B _ ~7 S - .010 TD = .0766 COf'3PUTED VALUES DUR = a.0o I l t_f = ~y . 15 010 .15 DR = .1S Cut~ ov, Cav►+iMuvus Grade a 7- 2tA f lowliv%e, devressioh, OA o~e►n'vi°~ 0.0-74fo' De,?t4n of stow 'M v%orv"v3 g~~~er C 0.15 C.- 's L7esigv% -DiSc~a+rccie a z D.v51 L 1 t C-A,, drum 1io (a) , p9• (-39 ~.v51 .9 . 15 .4227272727227 "SpakA~.e Cguvr't Gk~d~l+nes 4 QA'd : uv fir, Qpe+n~n~ ' w ic1e. } ~ ~ e~ 20WETRING CALCULATIONS DATE = 5/15/ 95 DESIGNER = K: W MCMUL KIN BASIN "A5 PROJECT NAM E = R.E. NORTH 6TH ADDIT ION DESCRIPTION = STORMWATER DRAINAGE t t Intensity Odev. Vtn VOUt Storage (rein.) (sec.) fin. /hr. 7 fc.+ . s. f (CU. f t.) (CU. ft.) (CU. ft. ) 5. 0 ~ 3cl0 L•. 18 . 115 59 9(_l -31 10.0 600 2.24 . 10 7:7 1 SO -107 1`,.0 900 1.77 OB 82 270 -18 3 20.0 1200 1.45 .07 883 160 - 27? 25. Cs 1500 1.21 .06 90 450 -360 :!;Q. 0 1 E300 1. 04 . 05 92 540 -448 - 35. 0 2100 .91 u4 9 z 67,0 - ;,7 40. 0 2400 .02 . 04 95 720 -62.,,E 45. Cl 2710 .74 . 0 , 96 X310 -714 50. 0 3000 .60 . 0:." 9B 900 -802 55.0 ~ ~ i1C1 .64 . 0 101 990 °884 60. 0 _600 .61 .0 10 5 1080 --975 65.0 31900 . 60 .0:1 1 1 1 1 170 -1059 70.0 4200 .58 .0- 116 1260 -1144 75. Cl 4500 .56 .0 119 1Z=f,0 -1231 80.0 4BOO .53 .02 121 1440 -1.x19 85.0 5100 .52 .02 1I5 157,,Ca --1405 90. C) 5400 .50 .02 128 1620 -1492 95.0 5700 .49 .02 1 Vi2 1710 -1578 10Cs.O 6000 .48 .02 136 1800 -1664 THE MAXIMUM STORAGE IS 0 CU. 1=T. * The time of concen tration is 5 minutes. The Undeveloped f l OW OUt 1s C . f . S. TEN YEAR STORM CAL_C 0.0166 DEPTH OF F OW - y - FEET .01 .02 .03 .04 .05 .0e "O .10 .2 .3 4 . s 6 7 6 9 10 I l I ! i i i l I I I I II 117 I LI ---f- I I 1 1 1 1 1 1 I~ I I I 11 . I I ~I I I I ~I ,I II I I t'll I I I I I ~ I I' ~ 1 1 1 1 1! 1 1 I I i l ' I (I I I I I ~ I I IF~~`.~ _ I I •1 X 1 1 I( I-- I ~ I( 0~ ~::I~- I I I~Ii1..1-! I g ~ ~I I I ti ~ 1 I I l l I' o I I + ~ I I I 1 I I 1 1 1 I I I I I I I I I I IIII I I I I ~I 1 1 1111!' I I I I I IIII I I I I 1 • I I I I III ICI ~I I I i l l (a) DISCHARGE PER FOOT OF LENGTH OF CURB OPENING INLETS WHEN INTERCEPTING 100% OF GUTTER FLOW (b) PARTIAL INTERCEPTION RATIO FOR INLETS OF LENGTH LESS THAN La 1.0 .9 .a .s .4 .3 .2 ~ - Qa La .10 :0s 06 o.oSl 505 ,04 .03 .02 .01 1.0 i .e ' 6 .s 4 Q 3 Q 0 x 10 .05 .06 08 .10 .2 .3 .4 .5 .6 .6 1.0 • I 1 I a/ - - - - ° o L L " j I I I I I L I - _ 06 / ~ I I t I I I I I ~ I 1 0, ~ o T- o 11 1, I I I -1-- I i I - - I I I f- I j 1 I• 1 I I I -t. I I I I I L/La CAPACITY OF CURB OPENING INLETS ON CONTINUOUS GRADE 6-39 FIGURE 16 ~'In{~~i''IVNT ~S7A'~i ~1~~T~1 ~~H ADU~Y4oN ~lvlZ~i6 ~F +~+XIAA.6e CALCUL.&-fION 5 ~~rGA ' a lQCn 1 v A~ TOTAL ~uoFS 1 - 2-ooD F-I.L z i Uoa r-\ Z3G~tivES LET` L 1~~d ~~i a z ODD l ~ I t l{a~ ~41.vvap -1 ~ ~DOD `~~,6~~ Ft• F~~~~ MFERV~13u~ g1DG~CMvNT S7 ATE 5 N~F:°~ F4 + P`D'GI~~Dr ~O . l? o G 42 4 ~ ~1k-'C . ~ 'Bow S'{ (IN G I 'D LE.. f5Ar-F-S L D F-Ywl L L z GFL c]u- ~T~RACE 1y5'D'. L I.I') ((07. (0e 5, )--z . 4J !~T`J s 3 0.33 ll~ I F 10 N L F'( ei i ,U _d I-dY D R C= L-1)Gy 'RC~ 1 T NA1E = F•,. L. NDRT1-1 6 1 i-i k`1L71) I ir,.i ~_SCIR a i'' I-1 1I -I' f:"i DRC~ WF'- FER 11 J L31-+f-,1.Nf iGE E IuEllA.13LA civ C:C r7 ~IJL.A;7E- i 1 RL11'Ql'-jF- F CwLIEF F I C I Fill" `-aC.lL~F REP 1 J k aL;F;ir '13U r"lF%Lri i IJf`JLJF F C C C F 1 CW 1 ENT - i s [ l ,'-ii=:F-,1 _ ~ ~ Li AC-, R I:-: C:L , 1dW'L] `s j 11, RLil~iOi- i- i_•I.7i= F i°° l C: i F kJ-!' » ari ~Ul =r'T ;::'LOW VALUES L - 0 ~ ~ rr 1 r` C.~-C-~{tiC°" e 6°-e_L;~+1 Sr',id_U=S I- ; ±L5 ' Z C . 17~ Z2 - 6 r jd _ C.3 6 5 5 U F. is a t_1 4 . ) 7 r,,ows-f l'7vI) CAL-GCII_t1T10111,=1 - it I F- "i iJ~M2f ti2I DI-S] LE ER' I• W I41E:..iyULl 11N1 E:EISI.N I I B F'I ,'0,JE 'C: I" 114A- I',IE E=t; P E. 1't1(3nTH 6°E°l I ADD . -)L1 SCR 1I=' T 7 ON w U I-(7RHW r'A TE-R D!- A l I IAOL_- t 1 9-~ ~.a?!~: l y •1 n Uou L Stcir aC;e {171 4 I} 3 5"r E7 C: ft I"~, fE°11 f ~C r` . ) ~Ctt. F +L ) 1 Ct it t~ ~Y ?.21 2. + ''tr1 1 .'?~Y 1 15L 0 77 r .26, ~ [:7X r,CYCt !tl F L7 i~y 'c i , tl 'm 1 lt_, I . 41._+ i . D6 2Al 16 ''I L 6- 21 1 - a 2. 15 t'. 1 1-1 -4 3 0 Crsr ~F}. fY ],f3(3Ci ] . (7LI _ '2`.a.1 °•Elt~7 X41.' , 5,, { t 1 1 1's .2:_9~ t I 4200 1 L, ;240" aid. 1„[Y nra 4i -LL}{Ysj ! `3(_Y , r) y'.Ct? YCl .Ear; [ ! o' , 6 Vc, css"aa 1(1 ;XJ 1 5 F. s9 EF_ ~ W~i_F! i . cs•T : e I _3 2 7 66001 - ~•(.31 •1 70. [-t -1 TO") . ~i1; y[3 ~r-t(! -':i',Y)7 ?I w L-) :.;={)i ] . 5 F . m7^C, r3 17,1 C), }C! c- i -7. r1r) 0 :#r1 ~Y . a ° . saC~ m r_ I ]t:Yt7 -E fe: .52 6 6 r, .6- 1 f'.Q ` 5,,{_! 7C.9C} .=Iq .6-- 6 IS -77L~ 1 0 6000 .43 .61 -7,418 12000 U, 1'H E' Ill 1X 1 N UN STC1RADE IS 10 7FI. cl~61.67 CU. F T. # The t-] mc-, of i ©ncen tnat3.on is 5 MA Ct+rtteS~ 11-1a Hrld(nV.-~1cipind flow k-fi-,-kt rEN YEAR' S1°OR11 C -ILC RATIONAL FORMULA HYDROLOSY DATE = 10/7/94 DESIGNEE: = K W MCMULKIN DAMN „8„ PAVT. PROJECT NAME = R.E. NORTH 6TH ADD. DESCRIPTION SUBAREA 1 TOTAL AREA OVERLAND FL Ct L N C = STORMWATER DRAINAGE - 36 ACRES .7,6 ACRES 3W VALUES _ .15 .4 .01 SUBAREA 1 RUNOFF COEF=FICIENT ~ .9 COMPOSITE RUNOFF COEFFICIENT ~ .R CHANNEL FLOW VALUES L 505 Z1 = .172 Z2 = 6 N - .016 D - cl 5 .018 TD = .1566 COMPUTED VALUES DUE; = 5.00 110 - 7.18 010 - 1.07 OA - 1.03 Cut- vP 1~NtN G A'T Law ? G IN T , ZTA. 31-t95,18 Sit ra.GI! -Nta1 1ne.15kt o~ D?entiv,,3 = 0-1566, wvier ~t e+,-Vrav~r-e G2 l•v3 C, s ~❑~al ~~ak rate of Flow (l~~~H}jt 0.158G ~ O.Z e 3 I ~ } r CuR op~N~ G 'n vli4~ ~a ee ~IUC ~MDN`C ~ 5'~~."C ~ ~ ~oRTi H ~ Th1 f~C]17. ~v. 1~.~ lG Cu-~TE~t S~CzAD DN SDt~a®P• 5'~,~2`~~~5 la, 5Ii1 ah C, - - - lS ° - - ~ 5.~8` --12.52- - ~z.z4 - - _ . S07a a -j 16% I Z'- ID -y- kyor =l9Ca~Mo~~~TA~ 6~1Cr~kl 6'IH.UU. Nv. 671 _ ~ e^1 l`rq -r D SV S L- OF 59 ~E17 ~o~~ i ~1~~4 1 ~~'0.Y'J YO~^,~--•-- - 0 t7 ~ U6~ - ~ 9Y - A Lr-~~~.~~~aus.~._'~~►Z~~._~._I~raUt7 ~ ~,C?.1~~].~_ `?~~~~i~._Fri_ p~~~ f,c~.~. ~-1~, 13a. x.°12 l~~ ~ ~5~_~~.2 G€' Ass [~tPG~Nto~vrt ES-Ovr5s wnF~Iw 6-rp App. tvr~, VL"It6 5 ~ ~1 C- ~~~-StTE UNpEVEI.aP~D C) Ck S+trY4, ?-ID ST lam. xK/rT. 3 cis 0..i) e D r LCI Is. 54 fi -7 +D RATIONAL FORMULA HYDROLOGY DATE = 4/21/ PROJECT NAME DESCRIPTION SUBAREA 1 = SUBAREA C = TOTAL AREA = MCMULKIN BASIN "C" 1 RUNOFF COEFFICIENT RUNOFF COEFFICIENT rE RUNOFF COEFFICIENT 95 = R. E. NORTH STORMWATER .61 ACRES 4.34 ACRES 4.97 ACRES DESIGNER = K W 6TH ADDITION DRAINAGE SUBAREA SUBAREA COMPOST OVERLAND FLOW VALUES Ct = .15 L = 530 N = .4 S .021 CHANNEL FLOW VALUES L = 0 TD = 0 COMPUTED VALUES DUR = 11.89 150 = ^.87 Ccii- 0 A .9 .15 .245070422505 BowsTRTNG CALCULATJONS MATE = 4/21 /95 DES IGNER = K W MCMUL1,1N BASIN "C" PROJECT NAM E = R, E. NORTH 61-1-1 ADDII"ION DESCRIPTION = STORMW ATER DRAIN AGE t t Ili tend ty Odev. V.t f } VOUt Storage (asIn. ~ (SEC.) din. /hr.) (CU. 'fit.) (CU. +t.) (CLL. ft.) 5.C] r0 0 4.57 C.57 --Lci 9C)(-) 13C8 10. 0 600 7 . 710 v,. 9(-) . 1:,4 1800 1 - w"4 11.9 71 ; 2.87 3.50 31',413 140 1207 15.0 900 22.45 2. 98 7.41 C1 2700 710 20.0 1200 1.97 2.44) 3461 3600 -1:719 25.0 1500 1.6B 2.0b :566 4-500 --9:!,4 0 . 0 180C) 1.46 1. 78 61,21 54CICI -1768 Z5. 0 2100 1 . 7C~ 1.58 .709 6700 2 15 91 40. 0 -240 0 1.18 1.44 2798 7200 - _;402 45. 0 270(? 1. Cab 1 . 2 ~ G71 01 00 -4229 0. 0 7-000 r .99 1.21 910 9000 - Cigo 55. 0 'C0 0 .92 1.12 970 99Cdiva - 5 9I-L 0 60.0 3 ca[:)0 .87 1.06 4072 10800 -67 28 65. 0 w9()0 .83, 1 . 01 4188 11 700 -7512 70.0 4200 .79 .96 4275 12-600 --F1 W 215 75.0 45 0 0 .77 .94 4448 1 ,00 -9052 8(--).0 480C) .75 .91 4606 14400 -9794 e5. o 51 L)O .7w .89 4750 15 _,0 -1 C) 5 JL► 9(-]. C) 5400 .71 .06 4880 16-26-1 -11 --',2 s 9s.0 5700 .69 .84 4994 17100 -12106 100.0 6000 .67 -62 094 1(300(-.) -12906 THE MAXIMUM STORAGE IS 1:~,7. 6-36`F 1999 CU. FT. The time o+ coneen tr,t 3 on is 1 1.€391',3 s;sl rtUte15. The Undevel oped flow out iii : e. f. sa. FIFTY YEAR STORM CAL C s RATIONAL FORMULA HYDROLOGY DATE = 10/7/94 DESIGNER = K W MCMULKIN BASIN "C" PAVT. PROJECT NAME = R.E. NORTH 6TH ADD. DESCRIPTION = STORMWATER DRAINAGE SUBAREA I = .24 ACRES TOTAL AREA = .24 ACRES OVERLAND FLOW VALUES Ct .15 L - 0 N .4 CHANNEL FLOW VALUES L r 332 Z1 = .172 Z2 = =6 N = .016 B = 0 5 = .007 TD = .16:3 COMPUTED VALUES DUR - 5.00 I10 - u.1S 010 _ .69 CAA - .69 SUBAREA 1 RUNCIFF COEFFICIENT .9 COMPOSITE RUNOFF COEFFICIENT = .9 C'UR'S Q?? ,XArvAG AT 1,OV4 FOiNT , SSA. l $.`3 $ kA = 0-\63 ' Deb- In air w o.'te.r o.t eh~rws~c~ Q 0•(09 C,~s Flo iot ~e~l~ r0.-ke- 0i --Flow 3f G~~~ ~F''~1yir~G } 4~ wide r Su d~e~ I'D MriR7 57fi'CIF-_ L Mog-fR 6TH ~.p17. t~`}lG S?REAlD Z]N SbNoRA 5'T. 412-419S F,AS I M 5 O v+~ DAS7 4~ ~ 1 170 Lo-- k ---\N.id ~N~ -~.r- v', + L~ .o W er_. -SAO ..~-AZI._._ AY -z- ~Q NY STORMWATER DRAINAGE CALCULATIONS FOR RIDGEMONT ESTATES NORTH 6TH ADDITION May 30, 1995 Prepared by: Simpson Engineers, Inc. North 909 Argonne Road Spokane, Washington 99212 TABLE OF CONTENTS I. Summary II. Stormwater Drainage Calculations for Basins A, B, and C of Ridgemont Estates North 6th Addition III. Attachments: * Soils Map and Tables =K Street and Drainage Plans. OFFICIAL PUBLIC DOCUMENT SPOKANE COUNTY ENGINEER'S OFFM ORIGINA PROJECT # suemmk # RETURN TO COUNTY ENGINEER Storrnwater Drainage Report; Ridgemont Estates North 6th Addition SUMMARY: The development is divided into three (3) basins; A, B, and C. See Drainage Map for Ridgemont Estates North Path Addition. Each basin is composed of two subareas; 1) grass lawns, and 2) impervious roofs, driveways, and asphalt paved streets- Stormwater flows overland across roofs, grass lawns, and driveways and into grass drainage ponds. Stormwater from asphalt streets flows along the curb gutters and into the grass drainage ponds through curb openings located at low points in the curb profile. The present drainage basin boundary for Basin A is shown on the drainage map. Basin A is primarily offsite with drainage flowing toward the plat- An earth berm will be constructed adjacent to the plat to intercept stormwater flowing onto the plat. 5torinwater will then pond up behind the berm and will percolate into the soil. The berm is temporary and will be removed when the adjacent unplatted portion of Ridgemont Estates (North is platted and developed. Basins An and As are onsite, and the stormwater drainage facilities for these basins will be constructed on the plat. The drainage basin boundary for Basin C will change slightly as adjacent portions of Ridgemont Estates North are platted. The basin area will remain about the same size, but the impervious subarea will, increase. Calculations for stormwater runoff were made for a present basin condition and a future condition- The -Future runoff condition for Basin C will require more drywells and storage than the present runoff condition. Therefore, the drainage detention and discharge facilities along Jonara Street will be designed for the future runoff condition, since modifications to the pond would be undesirable in the future. The grass percolation areas (drainage ,ponds) were calculated to hold the first 1/2" of rainfall runoff over the asphalt street areas. Figure 2, page 6-3, of the "Guidelines for Stormwater Management", by Spokane County Engineers, was used for rain-Fall intensity and duration occurring at a 10-year storm Frequency for onsite drainage. The Rational and Bowstring Methods were used to calculate the peak stormwater runoff for each basin, and the type and number of drywells needed for each basin based on the storage capacity of the pond. The S.C.S. QTR-55 method was used for calculating the stormwater runoff for Basin A. eS-TkTCS rDIZ-TH 6-THAIDDkl t~~a DF-P tNAGe CAS-CULAT1oN5 5f2 ~~t5 ITE , UNIDSVIELoPED 50-year storo.., . - - - AFP-- . - - - -1 Act= Ta~Ry PAv T. _ T. _._1 6R►~S5 7- DDY - - L Q- a_o pDv 533 Cis ver - ---C]►~ lgw_; F _ zry0,4i . [aI-+Ae for. ~Qd r1Sl7V1_ J0, i ~r►er Y- 'A ak er c ❑ i sn VD F- P f wi-t~ a Per m 9~t c1ev~~!Dpi 20 C° \A/ atle h a+~ ~1y315_' _ ev~$ia~_G3°~_~ AYE. .1 I I 1 TED T ~e a d Grain s`f'5pe- ~a hard kU O.OQr -11 $0.0 64.54 1 1 f k J - ~ n k I 1 s k I 9 lb ~0 I 0 0o v I In I riI ti ~i v In I 1 ! f I ~ 1~ / I Q G P N ! 39° I ~~ns~ruciI Ea,r~b Berm, I -TO!? D'i Berm ~Erv zo4~° ! ri , (fee pei I y AVY , -1 N- 7,~- - -VI ..:,515 .o, Xo l~ ko `9 c►i o U) ~I a ,n ~ e ~T r Q 1 80. 0 V N 1 1 `loo ble 5,1.rrel B r5*el1 f ~ Vro-me- and G!r 1 ~ Kok ne. Cvun-Y~ ~'~"andc~r~ ~ S#~.. ~to5, 25 ri9h~ I To ? of Gra#e E,~ev. 20-38L, 00.00, ' m d go+~d Elev Z09-7 P'23`17"W 125.00' 1 ak +ne C "a C 7 ~A ~-t'TE<i f7 G f ar EA f nv r El w. Z y `J Sp ao rv . 4t m -¢c 0~ c4cb El }pe b z i r ° P j ~ 5 BA ut r~ Tc Pe c l L!'W X, POND-2 Version: 5.15 SIN: 1295160123 Page 6 EXECUTED: 05-24-1995 11:27:45 SUMMARY OF ROUTING COMPUTATIONS Pond File: C:`PONDPACKIREN6 PND Inflow Hydrograph: C:\PONDPACK`REN6 HYD Outflow Hydrograph: C:1PONDPACK\REN6P HYD Starting Pond W.S. Elevation = 2038.00 ft Summary of Peak Outflow and Peak Elevation Peak Inflow = 7.10 cfs Peak Outflow - 0.23 cfs Peak Elevation = 2038.98 ft Summary of Approximate Peak Storage Initial storage = 0 cu-ft Peak Storage From Storm = 11.315 cu-ft Total Storage in Pond = 11,315 cu-ft POND-2 Version: 5.15 SIN: 1295160123 Pond File: C:\PONDPACK\REN6 Inflow Hydrograph: C:\PONDPACK\REN6 Outflow Hydrograph: C:IPONDPACK\REN6P Peak Inflow' = 7.10 cfs Peak outflow = 0.23 cfs Peak Elevation = 2038.98 ft 11.3 - 11.4 - 11.5 - 11.6 - 11.7 - 11.8 - 11.9 - 12.0 - 12.1 - 12.2 - 12.3 - 12.4 - 12.5 - 12.6 - 12.7 - 12.8 - 12.9 - 13.0 - 13.1 - 13.2 - TIP (hi * Fi x Fi 0.0 1.0 Page 7 PND HYD HYD EXECUTED: 05-24-1995 11:27:45 Flow (cfs) 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 11.0 x x x x x x x X* X X x x x x x x x x x x x x x x x x x x x x x x x x X x x x X :E le: C:\PONDPACK\REN6 le: C:/PONDPACK/REN6P * * * * .HYD Qmax = 7.1 cfs .HYD Qmax = 0.2 cfs POND-2 Version: 5.15 SIN: 1295160123 Ridgemont Estates North 6th Addition CALCULATED 05-24-1995 11:08:18 DISK FILE: C:\PCNDPACK`REN6 VOL Planimeter scale: 1 inch = 50 ft. * Elevation Planimeter Area AI+A2+sgr(A1*A2) Volume Volume Sum (ft) (sq.in. ) (sq.ft) (sq.ft) (cubic-ft) (cubic-ft) 2,038.00 0.41 1,025 0 0 0 2,039.00 11.30 28,250 34,656 11,552 11,552 2,040.00 25.21 63,025 133,470 44,490 56,042 * Incremental volume computed by the Conic Method for Reservoir Volumes. POND-2 Version: 5.15 SIN: 1295160123 EXECUTED: 05-24-1995 11:27:45 Page 1 * * * Ridgemont Estates North 6th Addition * soil outflow = 0.36 in./hr. per sq.ft. (Value for sod) * = 0.00000833 cfs per sq. ft. Inflow Hydrograph: C:/PONDPACK\REN6 Rating Table file: C:\PONDPACK\REN6 ----INITIAL CONDITIONS----- Elevation = 2038.00 ft Outflow = 0.01 cfs Storage = 0 cu-ft GIVEN POND DATA ELEVATIONI OUTFLOW P STORAGE (ft) (Cfs) (cu-ft) 2038.00 0.0 0 2039.00 0.2 11,552 2040.00 0.5 56,042 .HYD .PND INTERMEDIATE ROUTING COMPUTATIONS 2S/t 2S/t + 0 (cfs) (cfs) 0.0 0.0 64.2 64.4 311.3 311.9 Time increment (t) = 0.100 hrs. POND-2 Version: 5.15 SIN: 1295160123 EXECUTED: 05-24-1995 11:27:45 Pond File: C:IPONDPACKOREN6 PND Inflow Hydrograph: C:\PONDPACKIREN6 HYD Outflow Hydrograph: C:`PONDPACK\REN6P .HYD INFLOW HYDROGRAPH Page 2 ROUTING COMPUTATIONS TIME INFLOW I1+12 2S/t - O 2S/t + 0 OUTFLOW ELEVATION (hrs) (cfs) (cfs) (cfs) (cfs) (cfs) (ft) 11.000 0.00 -0.0 0.0 0.01 2038.00 11.100 0.00 0.0 -0.0 -0.0 0.00 2038.00 11.200 0.00 0.0 -0.0 -0.0 0.00 2038.00 11.300 0.00 0.0 -0.0 -0.0 0.00 2038.00 11.400 0.00 0.0 -0.0 -0.0 0.00 2038.00 11.500 0.00 0.0 --0.0 -0.0 0.00 2038.00 11.600 0.00 0.0 -0.0 -0.0 0.00 2038.00 11.700 0.40 0.4 0.4 0.4 0.01 2038.01 11.800 0.70 1.1 1.4 1.5 0.01 2038.02 11.900 1.10 1.8 3.2 3.2 0.02 2038.05 12.000 4.00 5.1 8.2 8.3 0.04 2038.13 12.100 'e7.10 11.1 19.2 19.3 0.08 2038.30 12.200 4.10 11.2 30.1 30.4 0.12 20738.47 12.300 1.70 5.8 35.7 35.9 0.14 2038.56 12.400 1.40 3.1 38.5 38.8 0.15 2038.60 12.500 1.20 2.6 40.8 41.1 0.15 2038.64 12.600 1.00 2.2 42.7 43.0 0.16 2038.67 12.700 0.90 1.9 44.2 44.6 0.17 2038.69 12.800 0.80 1.7 45.6 45.9 0.17 2038.71 12.900 0.80 1.6 46.8 47.2 0.17 2038.73 13.000 0.70 1.5 48.0 48.3 0.18 2038.75 13.100 0.60 1.3 48.9 49.3 0.18 2038.76 13.200 0.60 1.2 49.7 50.1 0.18 2038.78 13.300 0.60 1.2 50.6 50.9 0.19 20138.79 13.400 0.60 1.2 51.4 51.8 01.19 2038.80 13.500 0.60 1.2 52.2 52.6 0.19 2038.82 13.600 0.50 1.1 52.9 53.3 0.20 2038.83 13.700 0.50 1.0 53.5 53.9 0.20 2038.84 13.800 0.50 1.0 54.1 54.5 0.20 2038.85 13.900 0.40 0.9 54.6 55.0 0.20 2038.85 14.000 0.40 0.8 55.0 55.4 0.20 2038.86 14.100 0.40 0.8 55.4 55.8 0.20 2038.87 14.200 0.40 0.8 55.8 56.2 0.21 2038.87 14.300 0.40 0.8 56.2 56.6 0.21 2038.88 14.400 0.40 0.8 56.5 57.0 0.21 2038.88 14.500 0.40 0.8 56.9 57.3 0.21 2038.89 14.600 0.40 0.8 57.3 57-7 0.21 2038.90 14.700 0.40 0.8 57.7 58.1 4.21 2038.90 14.800 0.40 0.8 58.0 58.5 0.21 2038.91 14.900 0.40 0.8 58.4 58.8 0.22 2038.91 15.0001 0.40 0.8 58.8 59.2 0.22 2038.92 15.100 0.40 0.8 59.1 59.6 0.22 2038.93 15.200 0.40 0.8 59.5 59.9 0.22 2038.93 15.300 0.30 0.7 59.8 60.2 0.22 2038.93 15.400 0.30 0.6 59.9 60.4 0.22 2038.94 POND-2 Version: 5.15 SIN: 1295160123 EXECUTED: 05-24-1995 11:27:45 Pond File: C:/PONDPACK\REN6 Inflow Hydrograph: C:\PONDPACKIREN6 Outflow Hydrograph: C:/PONDPACK`REN6P INFLOW HYDROGRAPH .PND .HYD .HYD ROUTING COMPUTATIONS Page 3 TIME INFLOW I1+I2 2S/t - 0 2S/t + O OUTFLOW ELEVATION (hrs) (cfs) (cfs) (cfs) (cfs) (cfs) - - - - - - - - (ft) ' - 15.500 0.30 0.6 60.1 60.5 0.22 2038.94 15.600 0.30 0.6 60.2 60.7 0.22 2038.94 15.700 0.30 0.6 60.4 60.8 0.22 2038.94 15.800 0.30 0.6 60.5 61.0 0.22 2038.95 15.900 0.30 0.6 60.7 61.1 0.22 2038.95 16.000 0.30 0.6 60.9 61.3 0.22 2038.95 16.100 0.30 0.6 61.0 61.5 0.22 2038.95 16.200 0.30 0.6 61.2 61.6 0.23 2038.96 16.300 0.30 0.6 61.3 61.8 0.23 2038.96 16.400 0.30 0.6 61.5 61.9 0.23 2038.96 16.500 0.30 0.6 61.6 62.1 0.23 2038.96 16.600 0.30 0.6 61.7 62.2 0.23 2038.97 16.700 0.30 0.6 61.9 62.3 0.23 2038.97 16.800 0.30 0.6 62.0 62.5 0.23 2038.97 16.900 0.30 0.6 62.2 62.6 0.23 2038.97 17.000 0.30 0.6 62.3 62.8 0.23 2038.97 17.100 0.30 0.6 62.5 62.9 0.23 2038.98 17.200 0.30 0.6 62.6 63.1 0.23 2038.98 17.300 0.20 0.5 62.6 63.1 0.23 2038.98 17.400 0.20 0.4 62.6 63.0 0.23 2038.98 17.500 0.20 0.4 62.5 63.0 0.23 2038.98 17.600 0.20 0.4 62.5 62.9 0.23 2038.98 17.700 0.24 0.4 62.4 62.9 0.23 2038.98 17.800 0.20 0.4 62.3 62.8 0.23 2038.97 17.900 0.20 0.4 62.3 62.7 0.23 2038.97 18.000 0.20 0.4 62.2 62.7 0.23 2038.97 18.100 0.20 0.4 62.2 62.6 0.23 2038.97 18.200 0.20 0.4 62.1 62.6 0.23 2038.97 18.300 0.20 0.4 62.1 62.5 0.23 2038.97 18.400 0.20 0.4 62.0 62.5 0.23 2038.97 18.500 0.20 0.4 61.9 62.4 0.23 2038.97 18.500 0.20 0.4 61.9 62.3 0.23 2038.97 18.700 0.20 0.4 61.8 62.3 0.23 2038.97 18.800 0.20 0.4 61.8 62.2 0.23 2038.97 18.900 0.20 0.4 61.7 62.2 0.23 2038.97 19.000 0.20 0.4 61.7 62.1 0.23 2038.96 19.100 0.20 0.4 61.6 62.1 0.23 2038.96 19.200 0.20 0.4 61.6 62.0 0.23 2038.96 19.300 0.20 0.4 61.5 62.0 0.23 2038.96 19.400 0.20 0.4 61.5 61.9 0.23 2038.96 19.500 0.20 0.4 61.4 61.9 0.23 2038.96 19.600 0.20 0.4 61.3 61.8 0.23 2038.96 19.700 0.20 0.4 61.3 61.7 0.23 2038.96 19.800 0.20 0.4 61.2 61.7 0.23 2038.96 19.900 0.20 0.4 61.2 61.6 0.23 2038.96 20.000 0.20 0.4 61.1 61.6 0.23 2038.96 POND-2 Version: 5.15 SIN: 1295160123 EXECUTED: 05-24-1995 11:27:45 Pond File: C:/PONDPACK\REN6 PND Inflow Hydrograph: C:/PONDPACK/REN6 HYD Outflow Hydrograph: C:/PONDPACK/REN6P HYD INFLOW HYDROGRAPH Page 4 ROUTING COMPUTATIONS TIME INFLOW I1+I2 2S/t - 0 2S/t + 0 OUTFLOW ELEVATION (hrs) (cfs) (cfs) (cfs) (cfs) (cfs) (ft) 20.100 01.20 0.4 61.1 61.5 0.22 2038.96 20.200 0.20 0.4 61.0 61.5 0.22 2038.95 20.300 0.20 0.4 51.0 +61.4 0.22 2038.95 20.400 0.20 0.4 60.9 61.4 0.22 2038.95 20.500 0.20 0.4 60.9 61.3 0.22 2038.95 20.600 0.20 0.4 60.9 61.3 0.22 2038.95 20.700 0.20 0.4 60.8 61.3 0.22 2038.95 20.800 0.20 0.4 60.8 61.2 0.22 2038.95 20.900 0.20 0.4 60.7 61.2 0.22 2038.95 21.000 0.20 0.4 60.7 61.1 0.22 2038.95 21.100 0.20 0.4 60.6 61.1 0.22 2038.95 21.200 0.20 0.4 60.6 61.0 0.22 2038.95 21.300 0.20 0.4 60.5 51.0 0.22 2038.95 21.400 0.20 0.4 50.5 60.9 0.22 2038.95 21.500 0.20 0.4 60.4 60.9 0.22 2038.95 21.600 0.20 0.4 60.4 50.8 01.22 2038.94 21.700 0.20 0.4 60.3 60.8 0.22 2038.94 21.800 0.20 0.4 60.3 60.7 0.22 2038.94 21.900 0.20 0.4 60.3 60.7 0.22 2038.94 22.000 0.20 0.4 60.2 60.7 0.22 2038.94 22.100 0.20 0.4 X0.2 60.6 0.22 2038.94 22.200 0.20 0.4 60.1 60.6 0.22 2038.94 22.300 0.20 0.4 60.1 60.5 0.22 2038.94 22.400 0.20 0.4 60.0 60.5 0.22 2038.94 22.500 0.20 0.4 60.0 60.4 0.22 2038.94 22.600 0.20 0.4 60.0 60.4 0.22 2038.94 22.700 0.20 0.4 59.9 60.4 0.22 2038.94 22.800 0.20 0.4 59.9 60.3 0.22 2038.94 22.900 0.20 0.4 59.8 60.3 0.22 2038.94 23.000 0.20 0.4 59.8 60.2 0.22 2038.94 23.100 0.10 0.3 59.7 60.1 0.22 2038.93 23.200 0.10 0.2 59.4 59.9 0.22 2038.93 23.300 0.10 0.2 59.2 59.6 0.22 2038.93 23.400 0.10 0.2 58.9 59.4. 0.22 2038.92 23.500 0.10 0.2 58.7 59.1 0.22 2038.92 23.600 0.10 0.2 58.5 58.9 0.22 2038.91 23.700 0.10 0.2 58.2 58.7 0.21 2038.91 23.800 0.10 0.2 58.0 58.4 0.21 2038.91 23.900 0.10 0.2 57.8 58.2 0.21 2038.90 24.000 0.10 0.2 57.6 58.0 0.21 2038.90 24.100 0.10 0.2 57.3 57.8 0.21 2038.90 24.200 0.10 0.2 57.1 57.5 0.21 2038.89 24.300 0.10 0.2 56.9 57.3 0.21 2038.89 24.400 0.10 0.2 56.7 57.1 0.21 2038.89 24.500 0.10 0.2 56.5 56.9 0.21 2038.88 24.600 0.10 0.2 56.3 56.7 0.21 2038.88 POND-2 Version: 5.15 SIN: 1295160123 EXECUTED: 05-24°-1995 11:27:45 Pond File: C:\PONDPACK\PEN6 PND Inflow Hydrograph: C:/PONDPACK`REN6 HYD Outflow Hydrograph: C:/PONDPACK\REN6P .HYD INFLOW HYDROGRAPH TIME INFLOW (hrs) (cfs) 24.700 0.10 24.800 0.10 24.900 0.10 25.000 0.00 25.100 0.00 25.200 0.00 25.300 0.00 25.400 0.00 25.500 0.00 25.600 0.00 25.700 0.00 25.800 0.00 25.900 0.00 ROUTING COMPUTATIONS Page 5 I1+I2 2SIt - 0 2SIt + 0 OUTFLOW ELEVATION (cfs) (cfs) (cfs) (cfs) (ft) 0.2 56.0 56.5 0.21 2038.88 0.2 55.8 56.2 0.21 2038.87 0.2 55.6 56.0 01.21 2038.87 0.1 55.3 55.7 0.20 2038.86 0.0 54.9 55.3 0.20 2038.86 0.0 54.5 54.9 0.20 2038.85 0.0 54.1 54.5 01.20 2038.85 0.0 53.7 54.1 0.20 '2038.84 0.0 53.3 53.7 0.20 2038.83 0:0 52.9 53.3 0.20 2038.83 0.0 52.5 52.9 0.19 2038.82 0.0 52.1 52.5 0.19 2038.82 0.0 51.8 52.1 0.19 2038.81 POND-2 Version: 5.15 S/N: 1295160123 Executed 05-24-1995 09:53:15 Page 1 Multiply Hydrograph by Constant Unit HYD File: C:/P0NDPACK\REN6X10.HYD Output Hydrograph: C:/PONDPACK\REN6 HYD Multiplier Constant: .1 TIME Unit Multiplier Output Hydrograph (hrs) Ordinates Constant (cfs) 11.00 0.00 x 0.100 - 0.00 11.10 0.00 x 0.100 = 0.00 11.20 0.00 x 0.100 = 0.00 11.30 0.00 x 0.100 = 0.00 11.40 0.00 x 0.100 = 0.00 11.50 0.00 x 0.100 = 0.00 11.60 0.00 x 0.100 = 0.00 11.70 4.00 x 0.100 = 0.40 11.50 7.00 x 0.100 = 0.70 11.90 11.00 x 0.100 = 1.10 12.00 40.00 x 0.100 4.00 12.10 71.00 x 0.100 = 7.10 12.20 41.00 x 0.100 = 4.10 12.30 17.00 x 0.100 1.70 12.40 14.00 x 0.100 = 1.40 12.50 12.00 x 0.100 = 1.20 12.60 10.00 x 0.100 - 1.00 12.70 9.00 x 0.100 0.90 12.80 8.00 x 0.100 - 0.80 12.90 8.00 x 0.100 - 0.80 13.00 7.00 x 0.100 = 0.70 13.10 6.00 x 0.100 = 0.60 13.20 6.00 x 0.100 - 0.60 13.30 6.00 x 0.100 - 0.60 13.40 6.00 x 0.100 0.60 13.50 6.00 x 0.100 = 0.60 13.60 5.00 x 0.100 = 0.50 13.70 5.00 x 0.100 0.50 13.80 5.00 x 0.100 - 0.50 13.90 4.00 X 0.100 0.40 14.00 4.00 x 0.100 - 0.40 14.30 4.00 x 0.100 - 0.40 14.20 4.00 x 0.100 = 0.40 14.30 4.00 x 0.100 0.40 14.40 4.00 x 0.100 = 0.40 14.50 4.00 x 0.100 - 0.40 14.60 4.00 x 0.100 - 0.40 14.70 4.00 x 0.100 0.40 14.80 4.00 x 0.100 0.40 14.90 4.00 x 0.100 = 0.40 15.00 4.00 x 0.100 = 0.40 15.10 4.00 x 0.100 = 0.40 POND-2 Version: 5.15 SIN: 1295160123 Executed 05-24-1995 09:53:15 Page 2 Multiply Hydrograph by Constant Unit HYD File: C:\PONDPACK\REN6X10.HYD Output Hydrograph: C:IPONDPACK\REN6 HYD Multiplier Constant: .1 TIME Unit Multiplier Output Hydrograph (hrs) Ordinates Constant (cfs) 15.20 4.00 x 0.100 - 0.40 15.30 3.00 x 0.100 - 0.30 15.40 3.00 x 0.100 0.30 15.50 3.00 X 0.100 = 0.30 15.60 3.00 X 0.100 = 0.30 15.70 3.00 x 0.100 - 0.30 15.80 3.00 x 0.100 - 0.30 15.90 3.00 x 0.100 = 0.30 16.00 3.00 x 0.100 - 0.30 16.10 3.00 x 0.100 = 0.30 16.20 3.00 x 0.100 = 0.30 16.30 3.00 x 0.100 - 0.30 16.40 3.00 x 0.100 - 0.30 16.50 3.00 x 0.100 = 0.30 16.60 3.00 x 0.100 - 0.30 16.70 3.00 x 0.100 0.30 16.80 3.00 x 0.100 - 0.30 16.90 3.00 X 0.100 - 0.30 17.00 3.00 x 0.100 0.30 17.10 3.00 x 0.100 = 0.30 17.20 3.00 x 0.100 0.30 17.30 2.00 X 0.100 = 0.20 17.40 2.00 x 0.100 - 0.20 17.50 2.00 x 0.100 = 0.20 17.60 2.00 x 0.100 - 0.20 17.70 2.00 x 0.100 = 0.20 17.80 2.00 x 0.100 = 0.20 17.90 2.00 x 0.100 = 0.20 18.00 2.00 x 0.100 = 0.20 18.10 2.00 x 0.100 = 0.20 18.20 2.00 x 0.100 - 0.20 18.30 2.00 x 0.100 = 0.20 - 18.40 2.00 x 0.100 0.20 18.50 2.00 x 0.100 = 0.20 18.60 2.00 x 0.100 = 0.20 18.70 2.00 X 0.100 - 0.20 j 18.80 2.00 x 0.100 _ 0.20 - 18.90 2.00 x 0.100 = 0.20 19.00 2.00 x 0.100 = 0.20 19.10 2.00 x 0.100 = 0.20 19.20 2.00 x 0.100 = 0.20 POND-2 Version: 5.15 SIN: 1295160123 Executed 05-24-1995 09:53:15 Page 3 Multiply Hydrograph by Constant Unit HYD File: C:/PONDPACK/REN6K10.HYD Output Hydrograph: C:\PONDPACK\PEN6 HYD Multiplier Constant: .1 TIME Unit Multiplier Output Hydrograph (hrs) Ordinates Constant (Cfs) 19.30 2.00 x 0.100 0.20 19.40 2.00 x 0.100 = 0.20 19.50 2.00 x 0.100 - 0.20 19.60 2.00 x 0.100 = 0.20 19.70 2.00 x 0.100 = 0.20 19.80 2.00 x 0.100 w 0.20 19.90 2.00 x 0.100 = 0.20 20.00 2.00 x 0.100 = 0.20 20.10 2.00 x 0.100 - 0.20 20.20 2.00 x 0.100 - 0.20 20.30 2.00 X 0.100 = 0.20 20.40 2.00 x 0.100 - 0.20 20.50 2.00 x 0.100 = 0.20 20.60 2.00 x 0.100 = 0.20 20.70 2.00 x 0.100 - 0.20 20.80 2.00 x 0.100 = 0.20 20.90 2.00 x 0.100 = 0.20 21.00 2.00 x 0.100 = 0.20 21.10 2.00 X 0.100 - 0.20 21.20 2.00 x 0.100 = 0.20 21.30 2.00 x 0.100 = 0.20 21.40 2.00 x 0.100 = 0.20 21.50 2.00 x 0.100 - 0.20 21.60 2.00 x 0.100 = 0.20 21.70 2.00 x 0.100 = 0.20 21.80 2.00 x 0.100 W 0.20 21.90 2.00 x 0.100 0.20 22.00 2.00 x 0.100 0.20 - 22.10 2.00 x 0.100 - 0.20 i 22.20 2.00 X 0.100 = 0.20 22.30 2.00 X 0.100 = 0.20 22.40 2.00 x 0.100 = 0.20 22.50 2.00 x 0.100 - 0.20 22.60 2.00 x 0.100 - 0.20 22.70 2.00 x 0.100 = 0.20 22.80 2.00 x 0.100 = 0.20 22.90 2.00 x 0.100 = 0.20 23.00 2.00 x 0.100 0.20 23.10 1.00 x 0.100 0.10 23.20 1.00 x 0.100 = 0.10 23.30 1.00 x 0.100 = 0.10 POND-2 Version: 5.15 5/N: 1295160123 Executed 05-24-1995 09:53:15 Page 4 Multiply Hydrograph by Constant Unit HYD File: C:\PONDPACK\REN6X10.HYD Output Hydrograph: C:\PONDPACK/REN6 HYD Multiplier Constant: .1 TIME Unit Multiplier Output Hydrograph (hrs) Ordinates Constant (cfs) 23.40 1.00 x 0.100 - 0.10 23.50 1.00 x 0.100 = 0.10 23.60 1.00 x 0.100 = 0.10 23.70 1.00 x 0.100 - 0.10 23.80 1.00 x 0.100 = 0.10 23.90 1.00 x 0.100 0.10 24.00 1.00 x 0.100 = 0.10 24.10 1.00 x 0.100 = 0.10 24.20 1.00 x 0.100 - 0.10 24.30 1.00 x 0.100 = 0.10 24.40 1.00 x 0.100 - 0.10 24.50 1.00 x 0.100 = 0.10 24.60 1.00 x 0.100 = 0.10 24.70 1.00 X 0.100 - 0.10 24.80 1.00 x 0.100 = 0.10 24.90 1.00 X 0.100 - 0.10 25.00 0.00 X 0.100 - 0.00 25.10 0.00 x 0.100 0.00 25.20 0.00 x 0.100 = 0.00 25.30 0.00 x 0.100 - 0.00 25.40 0.00 X 0.100 w 0.00 25.50 0.00 x 0.100 = 0.00 25.60 0.00 x 0.100 = 0.00 25.70 0.00 x 0.100 = 0.00 25.80 0.00 x 0.100 0.00 25.90 0.00 x 0.100 = 0.00 Quick TR-55 Version: 5.45 SIN: 1315464151 Page 1 Return Frequency: 50 years TR-55 TABULAR HYDRVGRAPH METHOD Type II. Distribution (24 hr. Duration Storm) Executed: 05-24-1995 09:48:51 Watershed file: C:/PDNDPACK/REN6 MOP Hydrograph file: C:\P0NDPACX\REN6X10.HYD Ridgemont Estates North 6th Addition >>>s Input Parameters Used to Compute Hydrograph <r<< Subarea AREA CN TC * Tt Precip. Runoff Ia/p Description (acres) (hrs) (hrs) (in) (in) input/used Basin A @ 10x 104.40 70.0 0.10 0.00 2.60 0.50 1.33 .33 * Travel time from subarea outfall to composite watershed outfall point. I Subarea where user specified interpolation between Ia/p tables. Total area = 104.40 acres or 0.1631 sq.mi Peak discharge = 71 cfs »3> Computer Modifications of Input Parameters Ewer Input Values Rounded Values Ia/p Subarea Tc * Tt Tc * Tt Interpolated Ia/p Description (hr) (hr) (hr) (hr) (Yes/No) Messages Basin A @ 10x 0.10 0.00 Yes * Travel time from subarea outfall to composite watershed outfall point. Tc & Tt are available in the hydrCgraph tables. Quick TR-55 Version: 5.45 SIN: 1315460151 Page 2 Return Frequency: 50 years TR-55 TABULAR HYDROGRAPH METHOD Type II. Distribution (24 hr. Duration Storm) Executed: 05-241995 09:48:51 Watershed file: C:\PONDPACK\REN6 MOP Hydrograph file: C:/PONDPACKIREN6X10.HYD Ridgemont Estates North 6th Addition >>a> Summary of Subarea Times to Peak c<er Subarea Basin A @ 10x Composite Watershed Peak Discharge at Composite Outfall (cfs) 71 71 Time to Peak at Composite Outfall (hxs) 12.1 12.1 Quick TR-55 Version: 5.45 S/N:'1315460151 Page 3 Return Frequency: 50 years TR-55 TABULAR HYDROGRAPH ME'T'HOD Type II. Distribution (24 hr. Duration Storm) Executed: 05-24-1995 09:48:51 Watershed file: C:IPONDPACK`REN6 MOP Hydrograph file: C:\PONDPACK\REN6XIO.HYD Ridgemont Estates North 6th Addition Composite Hydrograph Summary (cfs) Subarea 11.0 11.3 11.6 11.9 12.0 12.1 12.2 12.3 12.4 Description - - - hr - hr hr hr hr hr hr hr hr - - Basin A @ 10x - - 0 0 0 11 40 71 41 17 14 Total (cfs) 0 0 0 11 40 71 41 17 -----e_ 14 Subarea 12.5 12.6 12.7 12.8 13.0 13.2 13.4 13.6 13.8 Description hr hr hr - hr hr hr hr hr hr Basin A@ 10x 12 - 10 - 9 8 7 6 6 - 5 5 Total (cfs) 12 10 9 8 7 - 6 6 5 5 Subarea 14.0 14.3 14.6 15.0 15.5 16.0 16.5 17.0 17.5 Description hr hr hr hr hr hr hr hr hr Basin A@ 10x 4 4 4 4 - 3 3 3 3 2 Total ( cfs ) 4 4 4 - 4 3 3 3 3 2 Subarea 18.0 19.0 20.0 22.0 26.0 Description - hr hr hr hr hr - - Basin A@ 10x 2 - - 2 2 2 0 Total (cfs) 2 2 2 2 0 Quick TR-55 Version: 5.45 SIN: 1315460151 Page 4 Return Frequency: 50 years TR-55 TABULAR HYDRCGRAPH METHOD Type II. Distribution (24 hr. Duration Storm) Executed: 05-24-1995 09:48:51 Watershed file: C: \PQNDPACK\REN 6 . MOP Hydrograph file: C:1PCN©PACKIREN6X10.HYD Ridgemont Estates North 6th Addition Time Flow (hrs) (cfs) 11.0 0 11.1 0 11.2 0 11.3 0 11.4 0 11.5 0 11.6 0 11.7 4 11.8 7 11.9 11 12.0 40 12.1 71 12.2 41 12.3 17 12.4 14 12.5 12 12.6 10 12.7 9 12.8 8 12.9 8 13.0 7 13.1 6 13.2 6 13.3 6 13.4 6 13.5 6 13.6 5 13.7 5 13.8 5 13.9 4 14.0 4 14.1 4 14.2 4 14.3 4 14.4 4 14.5 4 14.6 4 14.7 4 Time Flog (hrs) (cfs) 14.8 4 14.9 4 15.0 4 15.1 4 15.2 4 15.3 3 15.4 3 15.5 3 15.6 3 15.7 3 15.8 3 15.9 3 16.0 3 16.1 3 16.2 3 16.3 3 16.4 3 16.5 3 16.6 3 16.7 3 16.8 3 16.9 3 17.0 3 17.1 3 17.2 3 17.3 2 17.4 2 17.5 2 17.6 2 17.7 2 17.8 2 17.9 2 18.0 2 18.1 2 18.2 2 18.3 2 18.4 2 18.5 2 Quid TR-55 Version: 5.45 SIN: 1315460151 Page 5 Return Frequency: 50 years TR-55 TABULAR HYDROGRAPH METHOD Type IF. Distribution (24 hr. Duration Storm) Executed: 05-24-1995 09:48:51 Watershed file: C:\PONDPACK`REN6 MOP Hydrograph file: C:\PONDPACKIREN6X10.HYD Ridgemont Estates North 6th Addition Time Flow Time Flow (hrs) (cfs) (hrs) (cfs) 18.6 2 22.4 2 18.7 2 22.5 2 18.8 2 22.6 2 18.9 2 22.7 2 19.0 2 22.8 2 19.1 2 22.9 2 19.2 2 23.0 2 19.3 2 23.1 1 19.4 2 23.2 1 a 19.5 2 23.3 1 19.6 2 23.4 1 19.7 2 23.5 1 19.8 2 23.6 1 19.9 2 23.7 1 20.0 2 23.8 1 20.1 2 23.9 1 20.2 2 24.0 1 20.3. 2 24.1 1 20.4 2 24.2 1 20.5 2 24.3 1 20.6 2 24.4 1 20.7 2 24.5 1 20.8 2 24.6 1 20.9 2 24.7 1 21.0 2 24.8 1 21.1 2 24.9 1 21.2 2 25.0 0 21.3 2 25.1 0 21.4 2 25.2 0 21.5 2 25.3 0 21.6 2 25.4 0 21.7 2 25.5 0 21.8 2 25.6 0 21.9 2 25.7 0 22.0 2 25.8 0 22.1 2 25.9 0 22.2 2 22.3 2 Quick TR-55 Ver.5.45 5/N:1315460151 Executed: 09:47:08 05-24-1995 Ridgemont Estates North 6th Addition RUNOFF CURVE NUMBER SUMMARY Subarea Area CN Description (acres) (weighted) Basin A @ 10x 104.40 70 Quick TR-55 Ver.5.45 S/N:1315460151 Executed: 09:47:08 05-24-1995 Ridgemont Estates North 6th Addition RUNOFF CURVE NUMBER DATA Composite Area: Basin A @ lOx AREA SURFACE DESCRIPTION (acres) part. 3.60 grass 100.80 CN 98 69 COMPOSITE AREA 104.40 70.0 ( 70 ] R~D6EMoNT ~STA7E5 NORZH lo~N ADV~~~oN No. I'Z'll6 ~~AINA61~ CAI.Cu L-ATIoNS 4 ~24r95 hw m BAS IN N ON- S I'CE : l0-~eav,;'{'orw~ p.FZf A <o o, 315 F'C l . 3 `i Ac F -E YAV T. - I-ITH Avf-. z 6 , 426 -f P ~~~5 z S I_oTs @ 2000 -t loam _ Is,'ooo rt,z DR~v E S !~o"C IMQERV~oUS z ~,4Z~ -4- 15, 000 - 21 4Z~ Fz,Z o.49 ;,CF-6 All 6 RASS 001315 - ZIl,+z0 38,889 IfTi 0.$cl1cF=E t`~or -C ~5TAT 5 ND(?-CH 6Ytl ADL)kTtoN to -3ear s~ rr,,, NO M-1Ira m ` ° 7) .SI 1D 'r- ag~E '?F-QMibeD e q S 1 Zrl. S0 74, 14+ Z ~ RATIONAL F 013MULA HYDROLOGY DATE = 4/24/95 DESIGNER = F; W MCMULI IN BASIN "A" PROJECT NAME = R. E . IVORTH 6TH ADDITION DESCRIPTION = STORMWATER DRAINAGE SUBAREA 1 = .49 ACRES SUBAREA 3 RUNOFF C(3EFF I C I ENT = .9 SUBAREA ? = . e9 ACRES SUBAREA 2 RUNOFF COEFFICIENT = .15 TOTAL AREA = 1.1',0 ACRES OVERLAND FLOW VALUES C t = . 15 L - C3 N - .4 S = .O1 CHANNEL FLOW VALUES L 15 T1 = 172- 72 = w+6 N = .016 D - 0 S - .026 TD = . 18 ,6 r C011POSITE RUNOFF COEFFICIENT . 416=C)474752 6 COMPUTED VALUES DUR - CIO I1C) - C. 15 - 010 - IT .e 3 OA L Sf BOWSTRING CALCULATIONS DATE = 4/24 /95 DES IGNER = K W MCMULKIN BASIN "A" PROJECT NAME = R.E. NORTH 6TH ADDITION DESCRIPTION = STORMWATER DRAIN AGE t t Intensity Cldev. Vin Vout Storage (min.) (sec.) (in. /hr.) (r_. f. s.) (cu. ft.) (cu. ft.) (cu. ft.) 5.0 % 300 3.18 1.87-1 7=+4 -1.00 4ti,4 10. 0 600 2.24 1.29 9i ► _C 600 = 071 15. 0 900 1.77 1.02 10 19 900 119 20. 0 1200 1.45 .83 1085 1200 -1 15 25.0 1500 1.21 .70 1114 1500 -086 10.0 1800 1.04 .60 1136 1800 '-664 35.0 2100 .91 .52 1151 2100 -949 40.0 2400 .82 .47 1 179 2400 -1221 45.0 2700 .74 .43 1191 2700 -1509 50.0 3000 .68 .19 1212 1000 -1788 55.0 000 .64 .07 1251 1300 -2049 60.0 3600 .61 .35 1297 1600 -230*:. 65.0 3 900 .60 .14 1168 3900 25!2 70.0 4200 .58 .30 14!3 4200 -2767 75.0 4500 .56 .12 1467 4500 -301::, 80.0 4800 .51 .10 1490 4000 -0107 85.0 5100 .52 .00 1509 5100 -1561 90.0 5400 .50 .29 1580 5401 -3820 95.0 5700 .49 .28 1630 5700 -4067 100.0 6000 .48 .28 1683 6000 -417 THE MAXIMUM STORAGE IS 434.4178 CU. FT. The time of concentration is 5 minutes. The Undeveloped flow out is 1 c. f . s. TEN YEAR STORM CALC RATIONAL FORMULA HYDROLO{SY DATE = 4/24/95 DESIGNER = K W MCMULKIN BASIN "A" PROJECT NAME = R.E. NORTH 6TH ADDITION DESCRIPTION = PAVT. SUBAREA I = .49 ACRES SUBAREA 1 RUNOFF COEFFICIENT = .9 TOTAL AREA = .49 ACRES GE]#`1pos 1 TE RUNDFF COEFF I L I EN r _ .9 OVERLAND FLOW VALUES Ct = .1C L - C~ N - .4 S - . 01 CHANNEL FLOW VALUES L = 31 Z1 = .172 72 = -36 N = .016 O = 0 S = .026 TD = .166 COMPUTED VALUES DUR 5. 00 110 - x.15 010 - ~ 1.40 QA w 1.40 u,rb 0?e-hlh3 v~% Conii+nuotAS (Shade. 0. = Zµ D~lowl,v.e c t?resriov, ai tj~eneA5 o'k 6(~ 1 0~ - r) w In hvr m p,l yJ+(ax - l•4Q c.~5 des i~~n p~~cl~~Y9e. Q~ ~ O.loS ~runn ~ig. 1(~, {a~ ~ Pg. ~-3R "SQa~r~+nt Co~.+n~u~ 'Gv.i~elin~: ~ ~ -For 5~t vrw.wo,'rer ~'lana~~w►e,in~ SAS( ~ur~ QPe..+n1►ntJa ] w~6c~e , ~ r . r DEPTH OF FLOW - y w FEET I)A(06 . Or pt .03 ,04 .05 06 .08 .10 1 .3 2 4 ■ 3 8 7 B 9 10 I r~ F ~ I I 11 I ~l I ~ I I I I ~ 1 I 4- T 9 I I I I I I ~ I 1 1 .I 4 1 1 I.. 7T- I I I I ~ ' I I r I1I I I i I i~~ H I I I IT I I ~ 1 I IQ1./~, I I I l I I I~ I~ o~ ~-I- --I 1- $~~-1 I I" ~ I I I ~L I I I I I I 1! I I I 1 @ t_ -I i I I ~ I I ' 1 i lI` 1;~_r I I_I ~ j~ l I I 'I I I I ~"-II I I I ! 1 1 1 1 ` I ~ I, III I t l l l I I l f o~ I I I I I I 1 I I.Ir f I ~ 1I ,1 ~ 1I 11. ' ~ DISCHARGE II ~ i ~ I f I ~ I I I t a I i l PER FOOT OF LENGTH 'OF CURD OPENING INLETS WHEN INTERCEPTING 100 % OF GUTTER FLOW (b) PARTIAL INTERCEPTION RATIO FOR INLETS OF LENGTH LESS TITAN L. Ip .e .s .s .3 .2 ~a La IQ _Oe .03 ,p4 I .03 .02 .0r 10 s ° s I I I I I I o~ 1 I I l I I I I I I I x I / I I I I I I F~ ~wc 17 I i- I - I - --r i I i I I. ~ 1 I ~ i I I I I is -r L,o CAPACITY OF CURB OPENING INLETS ON CONTINUOUS GRADE 6.39 FIGURE 16 O Qa ~lDGSrhoN1 ~--5TA757-S 611-1 AflD. I~~tk~ KWM ~S4N Iy -DtA-511 : 1D-uJewr storm - A` G~r~ss A- 9_l5 ~-I fo = 3, 405 Fri AcR~ 4 . - ~7®~N 5'{CY• i+VR9 _ ~r~i ~ ~ ~ i1ng~~ ~7'xrr~l C~s - - ` u _ ~ ~ _ . _I x~. ~ ~ CL R+~n,+~s~ 1 {31^1 ~ p, 5 C~r~ ~ - - • - • _ 6 . _7.`~ -a 21 r -2- r w~ RAT IOI14AL FOR HULA HYDROLOGY MITE = 5/5/95 DESIGNER = K W I'"1C HULK l N PROJECT NAME = R. E . NORTH 6TH ADD I T MN DESCRIPTION = 5TORNWATER DRAINAGE S BASIN All LJ1;sr ~F+EA 1 = , Q4 ACRES SUBAREA 1 RUNOFF COEFFICIENT = .9 SUBAREA = .07 ACRES SUBAREA 2 RUNOFF COEFFICIENT = . 15 TOTAL AREA = . 11 ACRES C011POS 11-E RUNCIFF COEFFICIENT - .422727272727 OVERLAND FLOW VALUES Ct = .1S L 0 N - -016 S .01 CHANNEL FLOW! VALUES L - 9S Z1 = .172 Z = 76 N - . 0116 $ - C1 G = .X11 s TD _ .0766 _ COMPUTED VALUES DUR _ . GG I10 010 = .15 QA - .15 ' CUr~) z 'Z z 0,j-j F~awli~e dErrGS~i©r. c~~ o~e~,►r,c~ 0.0-74(o` Depth -low i►n +nvrv o.l 9N C p. 15 CAS D~ s ig+n b i cc ar_qe E" ~.v~~ rCrvws Fig pg. 6-39 Lq OAG r 2.q$ Q.051 " s pov- ay.e CtpwAl ~ ~auide.l►~nes 4 Svc StllrVl,water mrano,ge-Me-hC - I 4 SA'[ : eur D a"4 , deep DOWSTR IN(3 CA LCULATIONS DATE = 5/5/915 DESIGNER = K W MCMULKIN BASIN "A" PROJECT NAME = R. E . NORTH 6TH ADDIT ION DESCRIPTION = 51-ORMWATER DRAINAGE t t In Lensi ty Ddev. Vin VOUt Storage (min.) (sec.) (in. /hr.) (c. i- . s.) (cu. it.) (CU. ft.) Q:Lk. -ft.) ~ . 0 300 18 .15 '1 90 -311 107. 0 600 2.24 . 10 -Z 1801 -107 15.0 900 1.77 .08 82 270 -188 20.0 12001 1.45 .07 88 ~60 -272 25.0 1500 1.21 .(-.)6 90 450 -360 . O.0 1800 r 1.04 .05 92 540 --448 35.0 2100 .91 -04 93 670 -57 ,7 40. 0 2400 . 132 .04 95 720 -625 45. 0 2700, .74 . 07, 96 81 -714 50.0 3000 .68 .0~, 98 900 -802 55. 0 3:300 .64 .03 101 990 -889 60.0 3600 .61 . 0: 105 1 OBO -975 65. 0 7-900 .60 . O, 111 1170 -1059 70.0 4200 . 58 .0 116 12607 -1144 75. 01 454.10 .56 . , 119 1 x•50 -121:711 eo.0 4800 .5 .02 121 1440 --1319 85. 0 510I0 52 .02 125 1570 - 1405 90. 0 54070 .50 . 02 lib 16204 -1492 95. 57`= 0 .49 .02 l 32 1710 -1578 100.0 60.700 .4e . 02 1 -.6 1800 -1664 THE MAXIMUM STORAGE IS 0 CU. FT. The time of concen tration is 5 min utes. The Undeveloped flow out is .7 c . f . s. TEN YEAR STORM CALC I p.01 DEPTH OF F OW - y - FEET .01 ,512 .03 04 04 06 a .10 ~ r .4 e s a a e 9 10 i 11 ~ I i l1 I I I 1 !I - - - - - - + . ~ 1 I I I I lop I jil . ~ I I t~ 1 I 1~ 1 I I ~~1~1i1~ I~ I C I ts. I l ! X I! j° I I T~ I I I t I I II 1 1 I I ~I I kl .I I I 1 1 I I I I I I I II I I I I 'I R I I I I I I} I I I I I I~1 k~ l ~ I ` I d l 1 I I k l l l l 1 1 1 f l ~ I I ~ I I I l 1 ~ j l l {n) DISCHARGE PER FOOT OF LENGTH OF CURB OPENING INLETS WHEN INTERCEPTING 100% OF GUTTER FLOW (b) PARTIAL INTERCEPTION RATIO FOR INLETS OF LENGTH LESS THAN Lti IO .a .a .3 .4 3 Q~ Lo 10 .oa .03 .02 .01 1.0 .a s .s 4 Q 3 Q a 2 10 .05 08 .08 10 2 3 .4 .7 a ,8 1.0 L/LSD CAPACITY OF CURB OPENING INLETS ON CONTINUOUS GRADE 5-34 FIGURE 16 l I I 4- a! _---t---- -4- '-t7 ! I I I I 1 L I - 06 / ~ I I ~j` } I I I ~ I ~ I I ~ I 00, I n t I i . I_ i I I I I I I I I I 1 I ~»C~k~o~T Es7~T~~ I~o~`r~ ~-tH AD~e~t®N NpIZ~~G Df~F~1NAG~ CAI~CL]L ~.~idN5 9 19IR ICI d- _ 4= ~ M - 1,~`! i•$S O.a~ Act 2.0 DO 0 f-T.7-. L a"T a looo -F-t- z ooo FT, L ¢'Y d01>o ~tC7 3C~ 4 , c~Z ~Y ~.T7~ IS~F` G~P.S 138 50 z 210 Pve.F-S 17-9/-lr l2 t►~. BO'V4 a-t ~N_ I}w3. `C _ . ? . ou LE._ R -S.'L D F-YwS L L 5 ~~a1~~GE t~Ray3p+En . 30-36° 61 5.3 6 r 4AC 2.9 ~ z5 ~ rip ~ 65,36t 60 !'=i T ;i WC c~~E DESIGNER I' V! MCMLL?'Tl',l ROJ E€ -E- NAME F; . E. NORTH 6)-11H ADD.. rf i_ CE'1 1 FT f1)N i l-lftij j€"lfl 1 L- D1-', l C7X_ E_ _ f ) E`d - e . 13 - C) i 'L11'31 E E -,C) V l U EL IS DU i J . 47i 1 C) f ~)I CIA '=al.~~~~i=4EWr=~ i F;1»11~ai~lE°-f= i:C]~Te F- TC=if~l~i~- r:,7UD IFS 2 C(21 11 E''C1;-:1 1 "E RLJNOP C= € 'GE= ICE= 1 C.s I rP• T r 1 i'` BOWSTRING CALCULATJON~'; DA rE. _ m a, "^7=1 DES IGNER - N P1L:1' ULP ] N RA.:)'1I'1 "B'' i "'i;1mC: i• i'Jiil'1E _ R. I`. NORTH 6TH ADD., i)ESCRIPT1 ON `=i'frJRm wA fER DFt(y.[N i1RE t t InLewLty L,!dev. VLn yof_tt, Stf:)i aqF. (rain.) (sec., (in. /hr (c,.; s.) (cu. + L (c u. ft.) (CU. •4 t,. ) 5.0 soo 3.18 4.07 3616 60u 10.0 60n 2.74 2.27 3012 ITUO 012 15.0 900 j./7 T.26 2T69 1poo 46q 20.0 1200 KA5 L.86 24K 2AuO K -.5.0 Inoo 1.2! 1.54 24RO 7000 -52.) 1n.0 3000 3.OA 1.11 T503 7600 .10AC? 75.0 2100 .91 1.10 216q 421Q 40.0 TAOO .82 1.05 2625 40"n -21.75 45.0 270t; .04 .95 5:(00 --_-...F 50.0 Zoo-) .68 . L37 7699 6000 ' - -'-1 L U5.0 0300' .32 1786 6600 _701-1 60.0 1600 .61 .78 2889 7200 -401 65.0 3900 11 6'.1 .76 50A7 7800 - 4 7 5'-', fir)~i) 420-0 5£l , -r~a' ~•1,ri^ _ n ,•,.ar"; c') -52M 75.0 4500 .56 1171 7T68 9000 -577") 600 APOO .57 60 =1 9400 -627''3 85.0 Q00 .52 .06 1428 10200 -1772 90.0 5400) 1. t;r-) .6A S52n 1"gon -720-) 95.0 5700 .4? .63 1619 11400 -7762 10U.0 6000 .48 .6J 3710 12000 -0252 THE MAXIMUM STORAGE IS 1005. 6616 CU. FT. the t•] f e Of c one entr aLi rn is 5 minutes, V e (lndev?1 c)ped 4 low out 2 r°. f s. TEN YEAR STORM CALC DATE = 10/7/94 RATIONAL FORMULA HYDROLOGY DESIGNER = K W MCMULKIN BASIN "B" PAVT. PROJECT NAME = R.E. NORTH 6TH ADD. DESCRIPTION = STORMWATER DRAINAGE SUBAREA 1 = .16 ACRES TOTAL AREA = .36 ACRES OVERLAND FLOW VALUES Ct = .15 L = N - .4 S = .01 CHANNEL FLOW VALUES L = 505 Z1 = .172 Z2 = _,6 N - .016 B = 0 S = .018 TD _ .1586 COMPUTED VALUES DUR = 5.00 110 = 3.18 010 = 1.03 QA = 1.03 SUBAREA 1 RUNOFF COEFFICIENT = .9 COMPOSITE RUNOFF COEFFICIENT = .9 CuR$ OFSNIN6 AT LDW POINT , .STA. 31t98.18 = g~ o.Gl~ Total hei9hfi o-E opening K = 0-1566 DeietL► of wooer aA eh-trohce Q = I.03 CFS TotoA veok ra-tt o-( Flow Z 3.o81(L)~H~Z for H 1 K o.►S86 ` o.z.4 h h D (A d3 _ a Q 2L EM V. 3.0$l H 3iz 3•0~l 0.1586 3~z Cu[c$ OpENIrtG ~o wide I dee -VDG MQR7 ~ 5'TATEs iiDRTH ~~T4i p.D17. ~a. l2.I16 Gv~'tTE~ SP~~~p 'ON n k L1 L c 5 b' - - ~ - 0 5o' ~-IS' D •ICa ~`C eta 1 5 4d_.c _1Z t7KAY _ - { 1~` - t7K~Y RI~~EMDN-~ ES7igZ Ne ~H 6-TH EY~U. Nth. l ~lG W Ml ®t~-51Y~ 1~EVELoPEv ~bEv ► oPEp - OFF ~~wr 5tor_w~ _ _ - st . TE1~s g~DGEMvNT ESTATES No?.IH (o TN ADD, IV0. 1 LIIG 4~2i ~q5 D?-AINAGE CAL-CULATIDN-S VWM BASIN__ C- ----b N-StTE DEv~LoP~c ~ FF-SITE-UNDE-VeLOPED-•---50 ~2ar_ S~oYYv~_ z 12 ►N~ --..._....b~.._gowv 57R1-14 G. 3.._..._3.-.~?o.U.$LE. ASR - r sTo(Zp,GE pRovibE~ : - - ~,.-.`~'B F~•' > 133 . - - - . 6 0 - _ - _ o -o 2~1 ZS._". _..2.__21_...... 1.4 + ~ p• . _ . 2 Z - - 3~~ } ?c' - - -z•27 '15.36 t -7 o 2 2 RAI IONAL FORMULA HYDROLOGY DATE = 4/21/95 DESIGNER = K W MCMULI:IN BASIN "C" PROJECT NAME = R.E. NORTH 6TH ADDITION DESCRIPTION = STORMWATER DRAINAGE SUBAREA 1 = .60 ACMES SUBAREA C = 4.34 ACRES TOTAL AREA = 4.97 ACRES OVERLAND FLOW VALUES SUBAREA 1 RUNOFF COEFFICIENT = SUBAREA 2 RUNOFF COEFFICIENT = COMPOSITE RUNOFF COEFFICIENT = Ct = .15 L = 550 N = .4 S = .021 CHANNEL FLOW VALUES L - 0 TD = 0 COMPUTED VALUES DUR = 11.89 150 = 2.87 650 3 50 0A = C~, 66 .9 .15 .245070422505 DOWSTN I NG CALCULATIONS DATE: = 4/21 !95 DES IGNER = V W MCMULKIN BASIN "C" PROJECT NAM E ~ R. E . NORTH 6TH ADDITION DESCR I PT I ❑IV - STORMWATE R DRAIN AGE t t Isatensx ty Qdev. Viii Vaut Storage cbec. r tit,.1hr. r cc.f.s. 3 (ctn. ft.) (C:Lt, ft.) cC:Lt. ft.) 5. 0 0 4. 157 5.57 2'2' ;8 9uO 3 ~ a 10. Cl 600 --..2() 3. 9u : ti t rLh 1 800 3 3:114 1 1 . 9 717, 2. e37 Z.. ,r(} 7, ,48 214`.} 120 15.0 900 2. 45 2.913 741C) 2700 710 ^[1, [1 1200 1.97 r'.4(_1 ,461 7600 --1 19 25. 0 1 500 1.68 y'. 0S 7566 4 500 --9::4 4,1. rl 1 BOO 1.46 1.77 ~ 67. 2' 54C1Ci -1768 35. 0 i 1 CIO 1 . w,0, 1. 563 = 7019 67, 00 --2591 40. +J 2400 3, . 18 1.44 -_'796 7:200 -My4C12 45. 0 - 2700 1. OB 1 . - 2 31371 X3100 -4 29 50. 0 3i ]t iC} .99 1.21 X1910 9000 _t090 55. CD x300 . 9:1 1.12 397 0 990(1 -59,U 60. 0 36[ )C 1 . B7 1 .06 4s.) 7'2'' I (A300 -L-)728 65.1 35900 . e,3 1 . 01 4168 11700 -7512 7C}.0 420Cl .79 .96) 4275 122600 -0-725 75.o 45 Q 0 .77 .94 4448 1 _-.500 _9052 B0. C} 48(.)C) . 75 .91 4606 14400 -9794 85.0 5100 .7. .89 47501 15700 -1011 501 90. Ca I 540C.) .71 . @6 48130 1600 --1 1 320 95.0 5700 .69 .134 4994 17100 -12106 100.0 60100 .67 . B2 5094 113000 -12,906 THE Mr; I MUM STORAGE IS 1 x37. 63651999 GU. FT. The time of concentration 15 11.891-':, mi nuto5. The Undevel oped flow ❑u t 15 3 a. f. s. FIFTY YEAR STORM CALC -I RATIONAL FORMULA HYDROLOGY DATE = 1017!94 DESIGNER = K W MCMULKIN BASIN "C" PAVT. PROJECT NAME = R.E. NORTH 6TH ADD. DESCRIPTION ~ STORMWATER DRAINAGE SUBAREA 1 = .24 ACRES SUBAREA 1 RUNOFF COEFFICIENT = .9 TOTAL AREA = .24 ACRES; COMPOSITE RUNOFF COEFFICIENT = .9 OVERLAND FLOW VALUES Ct m .15 L 0 N .4 S - .01 CHANNEL FLOW VALUES L - 772 ZI = .172 Z2 = C6 N - .016 B 0 S - .007 TD - .16::- COMPUTED VALUES DUR = `1.00 1101 - - 3.15 01Ci - .69 QA = .69 GUR?, ol?,"`tAG Art ~-vW FoINT i SIP" 3 t t °18.~ 8 Vt ! z 0, (P-1 k `fatal ~a 6 tt &t of b V e yx' + 5 k'L D.163 ai w o,te.r a~ ev,+rav~cE C 0.(49 Cis lo-voA veak• rate a -'!ow 3.095-1 ~or - _ 0.163 0 , 2.4 C L -c 3•o8-7 04) 3VL 3.000 GuIF- 16 0 1? IF- IrmA NK G • 41 wade- ) $4 Ae eIF ~►l'[ DER SF'REAt3 ~ONoRA 5'T.1z41cs g~ 5 ~ ~ 5 , ~ ah~ KC~• - - -1'6'- - - - - - - - fig" - - - - - - - - C7L ! Y1 L~ b o s lv, ~l u - - - .4 4 l Z { .'...0 Y- AY.. SPOKANE COUNTY Isopluvials of 50 year 24 hoar precipitation in lenlhs of an inch. 24 26 28 30 F-kDGEM©NT S STATES ~ 22 FIGURE 4 Sheet 2 of 2 -7 22 2426 SPOKANE COUNTY Isopluviols of lQ year 24 hour precipitation in tenths of an inch. 20 26 26 26 26 24 j NOF -fH (TI, p,qp, C'6 p n e .I T f SPC • i . 6-6 i FIGURE' iRE 4 Sheet l of 2 appendix A: Hydrologic soil groups Soils are classified into hydrologic soil groups (HSG's) to indicate the minimum rate of infiltration obtained for bare soil after prolonged wetting. The HSG's, which are A, B, C, and D, are one element used in determining runoff curve numbers (see chapter For the convenience of TR-55 users, exhibit A-1 lists the HSG classification of Uruted States soils. The infiltration rate is the rate at which waiter enters the soil at the soil surface. It is controlled by surface conditions. HSG also indicates the transmission rate-the rate at %vhich the water move: within the soil. This rate is controller{ by the soil profile. Appi•aximate numenval ranges fur transmission rates shown in the HSG definitions were fu-st published by Musgrave (USDA 195-5). The four groups are defined by SCS Soil scientists as follows: Group A soils have low runoff potential and high infiltration rates even when thoroughly wetted. They consist chiefly of deep, ivell to excessively drained sands or gravels and have a high rate of water tr ansnussion (greater than 0.30 inlhr). Group B soils have moderate infiltration rates when thoroughly wetted and consist chiefly of moderately deep to deep, moderately well to well drained soils with moderately tine to'moderately coarse textures. These soils have a moderate rate of water transmission (0,13-0.30 in/hr). Group C soils have low infiltration rates when thoroughly wetted and consist chiefly of soils with a laver that impedes downward movement of water and soils with moderately fine to tine texture. These soils have a low rate of water transmission (0.05-0.15 in/hr). Group D soils have high runoff potential. They have verT low infiltration rates when thoroughly wetted and consist chiefly of clay soils with a high swelling potential, soils with a permanent high water table, soils u-ith a claypan or clay layer at or near the surface, and shallow soils over nearly impervious material. These soils have a very low rate of water transmission (0.0.05 irv`hr). In exhibit A•1, some of the listed ,,oils have an added modifier; for example, "Abrazo, gravelly." This refers to a gravelly phase of the Abraza series that is found in SCS soil map legends. Disturbed soil profiles As a result of urbanization, the soil profile may be considerably altered and the listed group classification may no longer apply. In these circumstances, use the fol)OWLnb to determine HSG according to the texture of the new surface soil, provided that sigrnifcant compaction has not occurred 03rakensiek and Rawls 1983): HSG Sort textures A Sand, loamy sand, or sandy loam B Silt loam or loam C Sandy clay loam Q Clay loam, silt%' clay loam, sandy clay, jilt- clay, or clay Drainage and group D sails Some boils in the list are in group D because of a high water table that creates a drainage problem. Once these soils are effectively drained, they are placed in a different group. For example, Ackerman soil is classified as A/D. This indicates that the drained Ackerman soil is in group A and the undrained soil is in group D. (210-VI-TR-55. Second Ed., June 1986) A-1 Exhibit A-1, continued: Hydrologic soil groups for United States soils _ FDfEST C l fUL5NC4-R C I GAPC01 0 l Leo FACeS TONE C I iULSTONr C I GAUD D 1 GILISPi9 0 fACEID.k s 0 1 fLS f oil 0 1 GaPD. OWAIMED 0 C 1 Rte I GCe5wwG C 1 GILL. ND W C fk[[r4TfA d i PUL}5 D I GAPPr1AIt14 a I Gatmoft C ! GILL. tW p faffifhfo r f R 0 GAGA I C C I GILL 1^0 C fACEttout a 1 fUkftk a I CONFER GECA i a 1 416L94Am p fRiLSOW&G 0 ! t WVAv 9 ! Get a1$1N a l G;LL5 C FACkgkl C I fUNNf5.i D I GOPfUiT a I Gtfa a l LiLLSauPG q rk4ft a I f°uR SNUA O I L+LCEko a C 14f15LL 1 49LC a I G1L+Arl A eOLkCN C I fvw1F Q I 4AACEi G l LEL41t C ! GILAC-4 C fkfvCNCACf F 0 l fuRY. 04AINfo C I GOACIA C I Gem p l ClrrrAR p fkCMCMjCkh C I f" UL IOA C 1 GAOL i IAS C I Gi:<f SID w0, C ! LILPIN q FACNCM^AN a l fusuv&A p I GAkC4p C I GtAtp G I G1Li0r q fRCr.CNTO■k 0 1 GAASIRA C 1 G+ACfLLp O l GCNSDk C 1 G1LSiDN p 1495.04■AICA p I S.aALDON a i 400rtNA 1 490441 .5 1 414-1 904t 0 fafsf40. P 1 4Aaa5 C i GAlihlheP a ! LcstLA of 0 1 41wLfIt a S-LIM9-ALKALC 1 4464VALLT ❑ 1 G01FOh1N+S FQ;4 6 ! Gef.CSff D I GinAr 0 fhtSNO. Tr1ICIL $06 U1. C i GA0[L L i GOGpktR 1L.t C . ! GtNEr. t a l GlktA 4 p . I GAaICA P 1 CARA t a I Lino* lwG[R 1 p fRC■■ fatiklia a Q 1 GAolkp 1 GAC l GaAtY I 6thOLA 0 p 1 CAN[ l G1kLA..D p p fa1Ah4 0 fr 1 GACNaDD c l GANf*01 LIhI1LLY D i 41..15. [ f61144I 0 1 L-C1dA 0 i GANFItLP C 1 Lek1AY D 141k5ER C tRIOLO 1 GADDfS C 1 LANNI4L 0 I CLOCQND■ C I L1pAAO Or f. l k D L r NO Eft C I DADDY 14AR IPilo C I LLCMADLA d r90 1 ! Ll4 G 6 FA IfDwa04 C 1 LAOaOEy A I GAACIm E I 4f O1rLC C>aE EI[ a 1 GIRD a fAiEkDS C I 4.050C40, rfi C C i GOpLANQ " t c 1 4tDRGtTp.R 0 615.1 1 p fR1ti.Dyw1P • I SuaSfg4luw 'LA LTT C I CCOR4 VILLE 4 0114 ! GLLP q FRIES O LAD r~ I LL I 40146 OCL 0 I QkWK IA L ! CA TAA 0 F41cSt■•.0 it 1 4AG46 C 1 Gs4,1k1%h C l LCPfFWD C I Llvlw C JrLE 5 Di4 p 1 GAROQP( 0 I LCPA i 4LACIfACAEt1C Fg1tii#Lt C ! GAG 1L ; I LphniG t I LEi k[F T q l LL 0D0E. a M IVES C 14rr•EE I LAkptD A l G06ALD 0 l LL rCEL p fHID 5. 1 GAIT C l GAWNI C. E I GCRFta 0 1 LLAOEYILLE B FR17hm C 1 La1ir O l CAko D 1 4LRDAUw 0 ! CL+Dfralfil p f Al3Tpq L I G-11.9 S b 1 C CARR 0 1 G9L INL r ! 44--05. ICht t fRl RP ► 1461Nt SackQ ! 4aFRE I io% if 1 L91iLaCN 0 1 LL-Q■ k 1 INI.CD B ! 6aiAfSr1L6E C 1 # 1 C►frR11I ' 1 LFA fl f5. 3 CtALANE p 14-4-4540. C fQj%jIC p i GALA IA ❑ I k C AApCC MA ~G I D Gf4lE a I G6455h£F y FL I Tt b I La}DAETrI a G ' I Gt++l+AkiO■k 6 1 LL. rrl D 'VdI4ZfLL L 1 G.LL>•UTI i C .yl:l r F I 41RNr.r F 4Lfr i 5 at. a 1144 CntPG D 0 1 C. -L t ! GAATCN &P C I Gfa.Cf. C I LLErE C fkooo 1 C.ALCk t l F G ' C I GtiROAI E 1 Li Er. p f ADti. A0,, C i 4A p LtoI 1 a i 6AG r 111 4ANY Ik D I GtLAAap C i W.F.n AP Ff.DL 1C 9 144LLSIAN■ l 4AVtA a/01 Cf WaAA0. Dealmcc' I I GLF.aAR. rCA L ffOL1C. C 1 4&LI*1111h A l A GPn 11 1 GtAST 0 1 GLt.afbG a `LfVATIDNg6001 AL C T I G a 1 GAS CLtt4 P 1 Lfi$it C '1 GLthol.AAa C •4DLIC. fLCgQCO P I LAL IL Ff C ! L f L 1 41$$NfA riI0 1 4L;kA0OD11 D f RQNDQQF 8 , .l SAL I$1fO C A5cf"Aa 11 1 LC5.1P 11+ it ! GL~hCAAa f fpONIIidAC q i G.L151f6. C fA$11. F 1 GEravaY 0 1 GL,fNCAB d. rEl. C 12041 Irv ' 4 ! 5.+LIk:"44-4-44-1 1 1 4.5Ga.1T G075Ar.T r I 0 L97CnEL6 C I SALI.f +4'+fVs 0 1 4+LL-hU 11 1 445.5114-4-: 1 4-1 T5AlL ❑ I GLL.c❑t a/Q fq,5t C I GA~Tp11 C I C Lf111S C I GLEN car PQAeOtD 0 FR01490 C I Gas a I GAT I LrIIVaLLE 0 1 4L[kOALf p R&WIFA it 644-Lt I N c! 4- 4 11 5 ! LCVI11: C 1 LLtN0AL1. rLT C r 84-31 TF 141.0 4 1 Lr.LL I A t I 6&1C5C. F 1 Lf v 5 L" L ! LLf Np.LL. AaRELT L Phuit"UR51 I C I LOLL1+• a 1 C+4I1T1t■ C 1 d 41aaLER C d fLOO0/0 OUIILA" ~ 4ALL 6 IQM n 1 &&190, 01 1 G1000" a l GL£w01FSDw d ff.UIIL'AID . C 4ALLFfOr a 1 '6419111'00 C I GIadDNSCWf£L C ! GLEND1rf p +•uQ;AaiE tY +C I I 4ALLWO f 1 Gr IL IA C I Llpai 0 I CLt.DDRA .110 iQUlil.k0, ■I;I C I 6440Q Ce01 GAIoff a l Lltkty C i GLCNEOEN p f a C 1 GALL D i G 0 I GIaSQtiYfLLE o I LLt N[LL a FRYf SuRG d 1 40LV■ aups F I GIarCLL C I P O R OAp F1. APU0 f L I GAL YE 5,3 L'!. f ! GfUL OY ~ 6 I L I Gso E Gig G C l 4LC.nALL C p f. 4AEEN a l GAL 1:1 L I - GF1LL IELOr C ! 4Lth"Aa q FUpA■ S 14aLviN . D 1 4.114-+N C I GIFFQAD 0 I GLfk•►4 4 fV0569 0 1 G01,*AT a l GAYIkS C i L144t0 C 1 4-L£.• ■ L fuCG3 C i 4■r9LEA a 1 GAVIP14 0 1 &ILA d 1 CLt..•...fN q FVf40SIA 14Ahp44 11 . 1 GAY 0 1 41LaERI D I GLt wOw• a fuff,4 C 1 LAr14EE C I GAYLA sVILL. a/Q1 4ILAD4 a l LLf.PDDL •++GrrEC 4 ! 4■NaQQ 0 1 . GATLIJ40 D I L1LaY 4 1 GLENRID 0 V" % k v" C ! G&MC4 4- 1 4*vkCd I f. SLA: "a 1SI 4 I LLfwaQif p OU&Chgg r L I 4Ae Oft a 1 G#TYlLLI C I GILCQ a` 1 LLf N■ D U$ p UL 0 A. A F Cf0 1 GANIf 0 i Gm1f LLf o I GIL CAEST a I 14Lfhsto 0 f VLL&w C I 4Af.hill a 4A101 D 1 LILT AD 1 4LfNI0 r. p fu".,p • D I U.-INIM C I C+trIL LI C 1 414-£& o a f CL LnT0.. ■dI C iULL£RIOw n l LAg5.nC R. PQkotD D i . GLAC"ARl C I GIL00&0 null GLtk105.w a f4LAEP R 0a I 1 1 EAR r 4 A GILTCAO. 0 I GLCn11 fVLAFA. QRA1wCQ C 1 (Ask ITC 1 CaFCry a l a I SIArI4f1f0 S L L I LLtnY1E C U*$TRATU^ 1 4LEk10k n 74 i COU i NTT, WASHINGTON Map I Soil mute sym4ol DsC Dragoon stony- silt loam, 0 to 30 percent slopes. DsD Dragoon stony silt loam, :30 to .55 per- cent slopes. DYD Dragoon very rocky complec, 21) to 55 percent slopes. P-~rrnvalmi1.y per hr. Av:ulahle 7,1 water Reaction I)sper~iu❑ Shrink-s%%ell capacit.% (1:5 dilution) potcntud In. prr in. q,,111 am! p// I Ek6 Lloika silt loam, U to 20 percent slopes. I 0• to 2 5 ; 0. 17 to 0. 21 0 8 to 2. 3 i 0. 12 to 0. 1; EIC Eloika very stony silt loam, 0 to 30 per- 5.0 to 10 0 0. Ofi to 0. of > to cent slopes. ! U 04 to 0. UG EID Eloika very- stony silt loam, 30 to 53 percent slopes. I Em Eindent silt loam. 0. S to 2 5 1 0. 17 to 0. 20 RS to 2. 5 0 17 to 0. 20 Fab Frecuran silt loam, 5 to 20 percent slopes. . 0. ? to 0 8 0. 17 to 0. 20 FaB3 Freeman silt loam, 5 to 20 percent slopes, severely eroded. 0. 2 to 0. 8 0 17 to 0. 20 FaC3 Freeman silt loam, 20 to 30 percent slopes, severely eroded. ; <0 0.5 0 17 to 0. 20 Fm Fresh water marsh. GaC3 Garfield silty clay loam, 0 to 30 percent I slopes, severely eroded. J 0.2 to 0 8 0. 17 to 0 16 GgA Garrison gravelly loam, 0 to 5 pe rcent U. (r) to 0 2 0. 21 to 2 5 0 14 to 0 17 0 17 to 0 20 slopes. f . . GgB Garrison gravelly- loam, 5 to 20 percent slopes O. S to 2 i 0 12 to 0 14 to 5 0 0 OS to 0 ] 0 ! >10 0 64 to 0 oG Gm6 Garrison very gravelly loam, 0 to 8 i percent slopes. 3; to 5. 0 0 OS to 0 10 5' to 5. 0 . O$ to 0 10 GnB Garrison very stony loam, 0 to 20 > 10 0 0.1 to U. 06 percent slopes, ! GpA Clenrose silt loam, 0 to 5 percent slopes. i GpB Clenrow silt loam, 5 to 20 perceutslope,, ; GpC Glenro~e silt loam, 20 to 30 percent dope,. . 8 • to 2 5 0 17 to 0.20 GpD Clenro-,e silt loam, 30 to 55 percent ,lope" ~ G 1 to G i G. 1 to G. f G 1 to 7. 6.6 to 7.:i 7.8 to 9.0 7.4to8 4 G6to7.3 6.6 to 7.3 6. 6 to 7. 3 i -fligh------ IIigh__. Ifigh_____-, Moderate__. Low------ \roderate--- Low Low------- - _ Low to mod- erate. Low. Low. Low. Low to mod- erate. Lo w•. Moderate. Low to-mod- Crate. Moderate. G 6 to 7. 3 Low \IOderate 6. 6 to 7. 3 Low- . Ifigh. 6. 6 to 7. 3 low- Moderate. 6. G to 7 3 \toder:rte Low G. 6 to 7_3 \loderatc___ . Low 6 6 to 7. 3 high------- . Low. G 1 to 6 G lfoderntc___ Low G 6 to 7 :3 Moderate--- . Low ti- G to 7. 3 111911 . Low. 6.1to73I ; Ifoderate__I 1 'Ow to moderate. ,;r j 92 Soil series or t'•pe' and m:,1, Fymbols Topsoil Dragoon (DrC, Good to DsC, DsD, poor. DvD). L• loika (Ek B, EIC, EI D). En,dent silt loam (Em). Freeman (Fa B, FaB3, FaC3). Garfield (GaC3)___I c 11'A HI\ GTON 93 Suitability as source of- Cuultinucrl Sand 1 Gravel 1 Isd ,Not suit- Not suit- able. able, nc•e ho Not suit- able. Nlot,suita- ble. fair to poor. Not, suits- Suitable at depth t o grea er tJhnn 60 inches. life, "Cot suRn- I si h ble. g . ro-. -Not suitn- blo. Fair to Not, Fuita- \ot suita- good. ble. ble. Garrison A, GCB, rn B, GnB). Fair- _ - I g,C Inntnote at end of table. Not suit- able. Good b(.)01\ - surface surface layer. Ind. rjcr- t to pur• i 1 (rsi,t - I IN r1'. lv II t Irr- :1• If(- Low r siztauce to crosion; mod- erate water- bulding eapne- ily; vcgelntion diflleult, to c talai,h exec-pt on Dragoon silt, lonln. Modernte resiSt- ance to erosion; moderate unieh. holding ca. )~ac•ity, vrgt•is• lion diflicult to establish exeept. on ]loikn silt, lonln. Moderate resist- :slue to erosion; very bigb'cater. holding it y; c.\cept for Sall -t oh-1 a nt. spccicv, %'Vgctn. Moll dlfhcull to establish. Alodernle resict- mice to clo,iou; very high'cnteh- bolding pralme• itv; vegetation fairly easy to rat n~,h~b. Alodprate resist. ante to vroSloll; vel v high 'cater•bobbng cal,nrit v; N119411:11 ion hilly cagy to 1•bl:l i,l i Sh. Alodl•rale resia- ancC 10 rrusion; lnudcl:,te to lu'c "tiler-holding capaeh' ; vog(, intion Alflirult. lu tStahl,-h on very Flpny loan), fnll)y cagy all otbl•h soils. Sewage dis},o.al I fields Trafh,cabilil} Alodrrnte to mudelalcly ral'id pern,c- ability; mod. el:,tcionod- crately rapid 'cater-holding capacity. Atodelnte to very rnpid pelulcnoility; model ate '+atcr•holding capacil}. 1'cry low shear strength; lo't• load-carrying capacity; lllodvrnle to modest cly rapid pvrmc- nbility. Low shear strength; mod- erate to high lo:ld-carrying capacity; mod. crate to very rnpid pernlc- nbilit Alodcrntc to modcral c•h• n' pern,~ vi nbilit y ; vcr'• high'catcl 'hold. ing capm-Ity; saturated in 'ChitO and spring; Modest ell s1o'c to very do'c pclhnc• nbilit} ;very high o•nler- holdiug ca- pality; Faill- ratcd in sph , ut;. AlodemIC to slow perine. abiht%•; very hilh'lnicr. holding en. pnrily. Alodcr•atc to very In)lid pl 1 n,t:a hihl y; hnodcratc• td, lo'c'cater- hnbliug ra- pacity. Veri low shear strength; mod. eh:Ate to low load-carrying capacity; mod. eratr to ;nod. ehately slow permca bil i t y. ''cry low ,h(-nr strc190); mod. eratr load. carrying ca. pacity; mod. thatch slow to ''ere slow pcrincabilit'•. Verv 1071 shear Ftrt•I,gl)); inod. ernle load. l.nrr' ing (.:I. parity; mod. crnle to blow }mnucabiht' . Iligh tibenr Cl reugt I, ; )jig], load-carrying e:,paelly- rllndelI1, to very rn1,id p,•7lnc: ilily. 1 I i (Joins sheet 67) _ C71 "4- I GO % ``-H S~<y1 ] J Y - r'te' o ( Y~ a r1 : _ _ ~ - ^ 1-~gA~ _ _ 1 V yr' - J ~ '-fir t~'1~ 1 1s.i SxB _ :E-q, 7 s 'ti,,, Est y ' --Y SAL _ s II': PoF - - :17 7r- GgB - - - . it c •-•~r s:~.~ - ` - - ~ ate, - • .1 ` 11 - . , ~:'~t..::-!} l X71 j GmB u' <y 1 ti J~ • ~ f r. ~ ~a" -.yam . 14' ,F.~£"'• ~ ~4 y~•'w i-~. - 3S GRA VEL `M _ ~I Fm l:<i.L y - P!T 1 tab j'. • i:`-~l Wit' : p,.`~ ~ . I - t , SPC~ ir7 = HhA Stc SPC j r Z E y r rf ` IPrSAA StC~ Bab SPC' I - i { (PoAz~ SDC SSC ] N ,i F- (Joins sheet 85) f ` i d °o Ln O ~ 0 0 0 0 4/ N f o- Ap,(~ FROM ANGLE DIST NORTH EAST TO AUTO INVERS E START 997.65035 1219.98745 2 2 INV N 0 36 43.0 E 140.0000 1137.64236 1221.48269 3 3 INV S 89 23 17.0 E 240.0000 1135.07910 1461.46900 4 4 INV S 0 36 43.0 W 400.0000 735. 10192 1457. 19690 5 5 INV N 73 40 46.0 W 166.2100 781.80876 1297.68441 6 6 INV N 0 36 43.0 E 40.0000 81.80648 1298. 11162 7 7 INV N 49 34 57.0 W 78.1000 872.44281 1238.65094 8 8 INV N 0 36 43.0 E 15.0000 997.43568 1239.98597 9 9 INV N 89 23 17.0 W 20.0000 997.64928 1219.98711 10 LAT & DEFT 0.00106 0.00034 10 HCLOSE N 17 45 41.7 E 0.0011 997.65035 119.98745 2 PREC = 1 TO 1083055 Area = 80600.24 sq ft 1.85033 ac STORMWATER DRAINAGE CALCULATIONS FOR RIDGEMONT ESTATES NORTH 6TH ADDITION May 30. 1995 Prepared ley: Simpson Engineers, Inc. North 909 Argonne Road Spokane, Washington 99212 co RECEIVED JUN 0 6 1995 TABLE OF CONTENTS SPOKANE COUNTY'ENGINEER Am a z. summary II. StormWater Drainage Caiculati®ns for Basins A, B, and C of Ridgemont Estates North 6th Addition III. Attachments: Soils Map and Tables 'w Street and Drainage Plans. %".P Mc S .P C7 IC A N E s" C C) U N -r Y inift DEPARTMENT OF BUILDING ANT] PLANNING A DIVISION OF THE PUBLIC WORKS DEPAR'T'MENT ]AmES L. MANSON, C.B.0, DIRECTOR ❑ENNIS M. SCOTT, P E, DIRECTOR MEMORANDUM RECOVER SEF 0 71995 a TO: Division of Engineeting and Roads cow Engineeit Division of Utilities Division of BmIdings Spokane County Health District Fire Protection District No. 1 Vera Water Power FROM: Louis Webster, Planner I DATE: September 7, 1995 SUBJECT: Proposed Final Plat of PE-1684-92 (Ridgemont Estates forth 6th Addition) Enclosed find copies of the above referenced final plat. Please review and forward any comments by September 18,1995. If you have any questions you may contact Louis Webster at 456-2205. Thank you. sam Enclosure e: Ken Tupper, 12929 E. Sprague, Spokane, WA 99216 Charles Simpson, 909 N. Argonne, Spokane, WA 99212 1E0Et\jED SFP 0 8 05 1026 WEST BROADWAY AVENUE • SPOKANE, WASHINGTON 99260 BUILDING PIdONE: (509) 456-3675 • FAX (509) 45611703 PLANNING PHONE. (509) 456-2205 • FAX (509) 455-2243 'I`DD !5091324-3166 S P Q I~ A N E CJ U N -r - x-OFFICE OF THE CouNTY ENGINEER r Ronald C. Hormann, P E., County Engineer A DivisiON OF THE PUBLIC WORKS DEPARTMENT Dennis M. Scott, P.E., Director September 5, 1995 Kevin McMulkim N. 909 Argonne Rd Spokane WA 99212 (509) 926-1322 f(509)926-1323 Kevin, Please submit a proposal describing who will own and maintain the `208' pond located at the easterly terminu of 17th Ave. The document must be submitted and the procedure determined acceptable to Spo e C ntyj$nor to final approval of the road plans. Paul Lennemann, E.I.T. Plans Review Engineer e4'~' Bean Franz, P.E. Plans Review Engineer cc:fiie 1026 W Broadway Ave. • Spokane, WA 99260-0170 • (509) 456-3600 FAX (509) 324-3478 TDD (509) 324-3166 STORMWATER DRAINAGE CALCULATIONS FOR RIDGEMONT ESTATES NORTH 6TH ADDITION April 9, 1996 Prepared by: Simpson Engineers, Inc. North 909 Argonne Road Spokane, Washington 99212 1. Summary 0 SPO E ouPIrr ENG. IQ% 0o r P-40&- NSTRUC~ o PERMIT REQUIRED! NOTIFY THE PERMIT ENGINEER 456-3600 24 HIPS. PRIOR TO CONSTRUCTION TI. Stormwater Drainage Calculations for Basins A, B, and C of Ridgemont Estates North 6th Addition 111. Attachments * Soils Map and Tables RECEIVED * Street and Drainage Plans APR 1 0 1996 SPOKANE COUNTY ENGINEER Stormwater Drainage Report; Ridgemont Estates North 6th Addition SUMMARY: the development is divided into three (3) basins; A, B, and C. See Drainage Map for Ridgemont Estates North 6th Addition. Each basin is composed of two subareas; 1) grass lawns, and 2) impervious roofs, driveways, and asphalt paved streets. Stormwater flows overland across roofs, grass lawns, and driveways and into grass drainage ponds. Stormwater from asphalt streets flows along the curia gutters and into the grass drainage ponds through curb openings located at low points in the curb profile. The present drainage basin boundary for Basin A is shown on the drainage map. Basin A is primarily otfsite with drainage flowing coward the plat. An earth berm will be constructed adjacent to the plat to intercept stcrmwater flowing onto the plat. Stormwater will then pond up behind the berm and will percolate into the soil, The berm is temporary and will be removed when the adjacent unplatted portion of Radgemont Estates North is platted and developed. Basins An and As are onsite, and the Stormwater drainage facilities for these basins will be constructed can the plat- fhe drainage basin boundary for Basin C will change slightly as adjacent portions of Ridgemont Estates North are platted. The basin area will remain about the same size, but the impervious subarea will increase. Calculations for stormwater runoff were made for a present basin condition and a future condition. The future runoff condition for Basin C will require more drywel.ls and storage than the present runoff condition. Therefore, the drainage detention and discharge facilities along Sonara Street will be designed for the future runoff condition, since modifications to the pond would be undesirable in the future- The grass percolation areas (drainage ponds) were calculated to hold the first 1/2" of rainfall runoff over the asphalt street areas. Figure 2, page 6-3, of the "Guidelines for Stormwater Management", by Spokane County Engineers, was used for rainfall intensity and duration occurring at a 14-year storm frequency for onsite drainage. The Rational and Bowstring Methods were used to calculate the peak Stormwater runoff for each basin, and the type and number of drywells needed for each basin based on the storage capacity of the pond. The S.C.S. QTR=55 method was used for calculating the stormwater runoff for B~ksi.n A. I ?-IV(Se IDR-T 5 Na TH A~~~~rors ~7F~Alr~YA~~ CA1~~UL►~YyaN~ UUAD'SV-EE-DPEU 5o-~eo~r stn-.,-- o ~r TOTAL. ASS _~w- r~ GO._._°._.1 r ~~D_._~-. J33t ? D.D Fl,' S-CU~~•G~. ~EC~1~I~EL' 1-UmE l1[ 5-f - sq. 1(1 ~eAY~^6, []rn f'oade } 5flti~ lS CO"p w~~ -G rJ` _ arc©~a 1VI l(0 s[zeH 9 S Kw" I_v.4 A c9~-- . v ACH=E ~ O.C]b Act{E - ~~~~AGE p9- ovti~E1 = ~C La , ovr ► 5 - c w s ~ 2 bT : "tDr ~ vl~ 5 ~,-a `~z-_..t.- of _~+1 oL+,, r _ w;ll ~reo~c~ o~ e.~rk v~1u~~►e„ _~1 ~ 315 .~l~v~~-i~+~ ~v3~ ° c - ----~-4.e.~e.~v~r~ ~.._wa_~' ~u~~~___5~or a_~~. vd~um~te _►_~-_~-~=®'!id~ ~ , _ . A V E. ..,_,w, I ~ f ~ I I 40- 1 I I . IV TTED ry ti 1 0.00 8 .00, 1 ~ ~ etl ~ "'C ~ e 8 ~ P F E N 1 I d Graff e. lord Lw 39° I F~zo3s$ a i a i I ° v- S 6cxck ~0tns~ ruck ,o r ~ Berm I TQQ flf Berm zo•}p° (See ❑e-i m } I 008 - 50 3 A + s$ - VEO 95.0 I in ilk ~--a° 1 f X15 + Crb nle~, 14 co Soak ne C un I _ I 7' TQ -f Cur' l u a I ga. Gr 3nl 1 w a ! 5A -4* t® ~a J of Clarks E1 `-Po ble $v.rrel Vr3,AeA ~ I-~ Pe I i&r 'ev s, ~ 1 ~ ` ! lrsi$~n Me-ta4 P~came and G~r ~'e,'['`~Pe. j~ak ne Coknt S~anda~rJd N J + '5t0. 4 t 05, 2-5 r i~h1 ~ lI ~ r ~ ToP Qf Gru#e ~1ev. 2o~g~ ~ I I 1 ~ I-o I 1 1 Cl(l. L)C]' $ o t~' m of Pond ~.le•~ 7-c) In __-n ut rte` 'j ~Q to N8?'23'170W 125.430' - - 7. c a i ► : .fe{fIS#[ A~it~{'s~~e: ~lliu~±~ 4 ~i ~~,:i, .,•,.,.ri ,7: t /`i s_1...... , t:}rte. _z.~~€ _.~;_:f~._..,~_•`?a ~ _ POND-2 Version: 5.15 SIN: 1295160123 EXECUTED: 05-24-1995 11:27:45 Page 6 SUMMARY OF ROUTING COMPUTATIONS Pond File: C:`PONDPACK\REN6 PND Inflow Hydrograph: C:/PONDPACK/REN6 HYD Outflow Hydrograph: C:`PONDPACK\REN6P HYD Starting Pond W.S. Elevation = 2038.00 ft Summary of Peak Outflow and Peak Elevation Peak Inflow = 7.10 cfs Peak Outflow = 0.23 Cfs Peak Elevation = 2038.95 ft Summary of Approximate Peak Storage Initial Storage Peak Storage From Storm Total Storage in Pond 0 cu-ft 11,315 cu-ft 11,315 cu-ft POND--2 Version: 5.15 SIN: 1295160123 Page 7 11.3 - 11.4 - 11.5 - 11.6 11.7 - 11.8 - 11.9 - 12.0 - 12.1 - 12.2 12.3 - 12.4 - 12.5 - 12.6 - 12.7 - 12.8 - 12.9 - 13.0 - 13.1 - 13.2 - TIN (hi * Fi x Fi Pond File: C:\PONDPACK\REN6 PND Inflow Hydrograph: C:\PONDPACK\REN6 HYD Outflow Hydrograph: C:`PONDPACK\REN6P HYD EXECUTED: 05-24-1995 Peak Inflow 7.10 cfs 11:27:45 Peak Outflow = 0.23 cfs Peak Elevation = 2038.98 ft Flow (cfs) 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 11.0 x x x x x x x X* x IX x x x x x x x x x x x x x 'x x x x x x x x x x x x x x _X X E 'S) le: C:\PONDPACK\REN6 le: C:IPONDPACKIREN6P * * * * .HYD Qmax = 7.1 cfs .HYD Qmax = 0.2 cfs POND-2 Version. 5.15 SIN: 1295160123 Ridgemont Estates North 6th Addition CALCULATED 05-24-1995 11:08:18 DISK FILE: C:/PONDPACK\REN6 VOL Planimeter scale: 1 inch = 50 ft. Elevation Planimeter Area Al+A2+sgr(Al*A2) Volume Volume sum (ft) (sq.in.) ' (sq.ft) (sq.ft) (cubic-ft) (cubic-ft) 2,038.00 0.41 1,025 0 0 0 2,039.60 11.301 28,250 34,656 11,552 11,552 2,040.00 25.21 63,025 133,470 44,490 56,042 * Incremental volume computed by the Conic Method for Reservoir Volumes. POND-2 Version: 5.15 SIN: 1295160123 EXECUTED: 05-24-1995 11:27:45 Page 1 * Ridgemont Estates North 6th Addition * soil outflow = 0.36 in./hr. per sq.ft. (Value for sod) * = 0.00000833 cfs per sq.ft. Inflow Hydrograph: C:\PONDPACKOREN6 Rating Table file: C:\PONDPACK\REN6 ----INITIAL CONDITIONS---- Elevation - 2038.00 ft Outflow = 0.01 cfs Storage - 0 cu-ft GIVEN POND DATA ELEVATION OUTFLOW STORAGE (ft) (cfs) (cu-ft) 2038.00 0.0 0 2039.00 0.2 11,552 2040.00 0.5 56,042 . HYD .PND INTERMEDIATE ROUTING COMPUTATIONS 2S/t 2S/t + 0 (cfs) (cfs) 0.0 0.0 64.2 64.4 311.3 311.9 Time increment (t) = 0.100 hrs. r POND-2 Version: 5.15 SIN: 1295360123 EXECUTED: 05-24-1995 11:27:45 Pond File: C:\PONDPACK/REN6 Inflow Hydrograph: C:/PONDPACK/REN6 Outflow Hydrograph: C:/PONDPACK\REN6P INFLOW HYDROGRAPH .PND .HYD .HYD ROUTING COMPUTATIONS Page 2 TIME INFLOW 11+I2 2S/t - 0 2S/t + ❑ OUTFLOW ELEVATION (hrs) (cfs) (cfs) (cfs) (cfs) (cfs) (ft) 11.000 0.00 -0.0 0.0 0.03 2038.00 11.100 0.00 0.0 -0.0 -0.0 0.00 2038.00 11.200 0.00 0.0 -0.0 -0.0 0.00 2038.00 11.300 0.00 0.0 -0.0 -0.0 0.00 2038.00 11.400 0.00 0.0 -0.0 -0.0 0.00 2038.00 11.500 0.00 0.0 -0.0 -0.0 0.00 2038.00 11.600 0.00 0.0 -0.0 -0.0 0.00 2038.00 11.700 0.40 0.4 0.4 0.4 0.01 2038.01 11.800 0.70 1.1 1.4 1.5 0.01 2038.02 11.900 1.10 1.8 3.2 3.2 0.02 2038.05 12.000 4.00 5.1 8.2 8.3 0.04 2038.13 12.100 ~-=,7.10 11.1 19.2 19.3 0.08 2038.30 12.200 4.10 11.2 30.1 30.4 0.12 2D38.47 12.300 1.70 5.8 35.7 35.9 0.14 2038.56 12.400 1.40 3.1 38.5 38.8 0.15 2038.60 12.500 1.20 2.6 40.8 41.1 0.15 2038.64 12.600 1.00 2.2 42.7 43.0 0.16 2038.67 12.700 0.90 1.9 44.2 44.6 0.17 2038.69 12.800 0.80 1.7 45.6 45.9 0.17 2038.71 12.900 0.80 1.6 46.8 47.2 0.17 2038.73 13.000 0.70 1.5 48.0 48.3 0.18 2038.75 13.100 0.60 1.3 48.9 49.3 0.18 203'8.76 13.200 0.60 1.2 49.7 50.1 0.18 2038.78 13.300 0.60 1.2 50.6 50.9 0.19 2038.79 13.400 0.60 1.2 51.4 51.8 0.19 2038.80 13.500 0.60 1.2 52.2 52.6 0.19 2038.82 13.600 0.50 1.1 52.9 53.3 0.20 2038.83 13.700 0.50 1.0 53.5 53.9 0.20 2038.84 13.800 0.50 1.0 54.1 54.5 0.20 2038.85 13.900 0.40 0.9 54.6 55.0 0.20 2038.85 14.000 0.40 0.8 55.0 55.4 0.20 2038.86 14.100 0.40 0.8 55.4 55.8 0.20 2038.87 14.200 0.40 0.8 55.8 56.2 0.21 2038.87 14.300 0.40 0.8 56.2 56.6 0.21 2038.88 14.400 0.40 0.8 56.5 57.0 0.21 20138.88 14.500 0.40 0.8 56.9 57.3 0.21 2038.89 14.600 0.40 0.8 57.3 57.7 07.21 2038.90 14.700 0.40 0.8 57.7 58.1 0.21 2038.90 14.800 0.40 0.8 58.0 58.5 0.21 2038.91 14.900 0.40 0.8 58.4 58.8 0.22 2038.91 15.0007 0.40 0.8 58.8 59.2 0.22 2038.92 15.100 0.40 0.8 59.1 59.6 0.22 2038.93 15.200 0.40 0.8 59.5 59.9 0.22 2038.93 15.300 0.30 0.7 59.8 60.2 0.22 2038.93 15.400 0.30 0.6 59.9 60.4 0.22 2038.94 POND-2 Version: 5.15 SIN: 1295160123 EXECUTED: 05-24-1995 11:27:45 Pond File: C:1PONDPACK\REN6 PND - Inflow Hydrograph: C:IPONDPACK\REN6 HYD Outflow Hydrograph: C:\PONDPACK/REN6P HYD INFLOW HYDROGRAPH Page 3 ROUTING COMPUTATIONS TIME INFLOW I1+I2 2S/t - O 2S/t + O OUTFLOW ELEVATION (hrs) (cfs) (cfs) (cfs) (cfs) (cfs) (ft) 15.500 0.30 0.6 60.1 60.5 0.22 2038.94 15.600 0.30 0.6 60.2 60.7 0.22 2038.94 15.700 0.30 0.6 60.4 60.8 0.22 2038.94 15.800 0.30 0.6 60.5 61.0 0.22 2038.95 15.900 0.30 0.6 60.7 61.1 0.22 2038.95 16.000 0.30 0.6 60.9 61.3 0.22 2038.95 16.100 0.30 0.6 61.0 61.5 0.22 2038.95 16.200 0.30 0.6 61.2 61.6 0.23 2038.96 16.300 0.30 0.6 61.3 61.8 0.23 2038.96 16.400 0.30 0.6 61.5 61.9 0.23 2038.96 16.500 01.30 0.6 61.6 62.1 0.23 2038.96 16.600 0.30 0.6 61.7 62.2 0.23 2038.97 16.700 0.30 0.6 61.9 62.3 0.23 2038.97 16.800 0.30 ' 0.6 62.0 62.5 0.23 2038.97 16.900 0.30 0.6 62.2 62.6 0.23 2038.97 17.000 0.30 0.6 62.3 62.8 0.23 2038.97 17.100 0.30 0.6 62.5 62.9 0.23 2038.98 17.200 0.30 0.6 62.6 63.1 0.23 2038.98 17.300 0.20 0.5 62.6 63.1 0.23 2038.98 17.400 0.20 0.4 62.6 63.0 0.23 2038.98 17.500 0.20 0.4 62.5 63.0 0.23 2038.98 17.600 0.20 0.4 62.5 62.9 0.23 2038.98 17.700 0.20 0.4 62.4 62.9 0.23 2038.98 17.800 0.20 0.4 62.3 62.8 0.23 2038.97 17.900 0.20 0.4 62.3 62.7 0.23 203'8.97 18.000 0.20 0.4 62.2 62.7 0.23 2038.97 18.100 0.20 0.4 62.2 62.6 0.23 2038.97 18.2030 0.20 03.4 62.1 62.6 0.23 2038.97 18.300 0.20 0.4 62.1 62.5 0.23 2038.97 18.400 0.20 0.4 62.0 62.5 0.23 2038.97 18.500 0.20 0.4 61.9 62.4 0.23 2038.97 18.600 0.20 0.4 61.9 62.3 0.23 2038.97 18.700 0.20 0.4 61.8 62.3 0.23 2038.97 18.800 0.20 0.4 61.8 62.2 0.23 2038.97 18.900 0.20 0.4 61.7 62.2 0.23 2038.97 19.000 0.20 0.4 61.7 62.1 0.23 2038.96 19.100 0.20 0.4 61.6 62.1 0.23 2038.96 19.2001 0.20 0.4 61.6 62.0 0.23 2038.96 19.306 0.20 0.4 61.5 62.0 0.23 2038.96 19.400 0.20 0.4 61.5 61.9 0.23 2038.96 19.500 0.20 0.4 61.4 61.9 0.23 2038.96 19.600 0.20 0.4 61.3 61.8 0.23 2038.96 19.700 0.203 0.4 61.3 61.7 0.23 2038.96 19.800 0.20 0.4 61.2 61.7 0.23 2038.96 19.900 0.20 0.4 61.2 61.6 0.23 2038.96 20.000 0.20 0.4 61.1 61.6 0.23 2038.96 POND-2 Version: 5.15 SIN: 1295160123 EXECUTED: 05-24-1995 11:27:45 Pond File: C:/PONDPACK\REN6 PND Inflow Hydrograph. C:/PONDPACK/REN6 HYD Outflow Hydrograph: C:IPONDPACKIREN6P HYD INFLOW HYDROCRAPH Page 4 ROUTING COMPUTATIONS TIME INFLOW 11+12 2S/t - O 2S/t + 0 OUTFLOW ELEVATION (hrs) (cfs) (cfs) (cfs) (cfs) (cfs) (ft) 20.100 0.20 0.4 61.1 61.5 0.22 2038.96 20.200 0.20 0.4 61.0 61.5 0.22 2038.95 20.300 0.20 0.4 61.0 61.4 0.22 2038.95 20.400 0.20 0.4 60.9 61.4 0.22 2038.95 20.500 0.20 0.4 60.9 61.3 0.22 2038.95 20.600 0.20 0.4 60.9 61.3 0.22 2038.95 20.700 0.20 0.4 60.8 61.3 0.22 2038.95 20.800 0.20 0.4 60.8 61.2 0.22 2038.95 20.900 0.20 0.4 60.7 61.2 0.22 2038.95 21.000 0.20 0.4 60.7 61.1 0.22 2038.95 21.100 0.20 0.4 60.6 61.1 0.22 2038.95 21.200 0.20 0.4 60.6 61.0 0.22 2038.95 21.300 0.20 0.4 60.5 61.0 0.22 2038.95 21.400 0.20 0.4 60.5 60.9 0.22 2038.95 21.500 0.20 0.4 60.4 60.9 0.22 2038,95 21.600 0.20 0.4 60.4 60.8 0.22 2038.94 21.700 0.20 0.4 60.3 60.8 0.22 2038.94 21.800 0.20 0.4 60.3 60.7 0.22 2038.94 21.900 0.20 0.4 60.3 60.7 0.22 2038.94 22.000 0.20 0.4 60.2 60.7 0.22 2038.94 22.100 0.20 0.4 60.2 60.6 0.22 2038.94 22.200 0.20 0.4 60.1 60.6 0.22 2038.94 22.300 0.20 0.4 60.1 60.5 0.22 2038.94 22.400 0.20 0.4 60.0 60.5 0.22 2038.94 22.500 0.20 0.4 60.0 60.4 0.22 2038.94 22.600 0.20 0.4 60.0 60.4 0.22 2038.94 22.700 0.20 0.4 59.9 60.4 0.22 2038.94 22.800 0.20 0.4 59.9 60.3 0.22 2038.94 22.900 0.20 0.4 59.8 60.3 0.22 2038.94 23.000 0.20 0.4 59.8 60.2 0.22 2038.94 23.100 0.10 0.3 59.7 60.1 0.22 2038.93 23.200 0.10 0.2 59.4 59.9 0.22 2038.93 23.300 0.10 0.2 59.2 59.6 0.22 2038.93 23.400 0.10 0.2 58.9 59.4 0.22 2038.92 23.500 0.10 0.2 58.7 59.1 0.22 2038.92 23.600 0.10 0.2 58.5 58.9 0.22 2038.91 23.700 0.10 0.2 58.2 58.7 0.21 2038.91 23.800 0.10 0.2 58.0 58.4 0.21 2038.91 23.900 0.10 0.2 57.8 58.2 0.21 2038.90 24.000 0.10 0.2 57.6 58.0 0.21 2038.90 24.100 0.10 0.2 57.3 57.8 0.21 2038.90 24.200 0.10 0.2 57.1 57.5 0.21 2038.89 24.300 0.10 0.2 56.9 57.3 0.21 2038.89 24.400 0.10 0.2 56.7 57.1 0.21 2038.89 24.500 0.10 0.2 56.5 56.9 0.21 2038.88 24.600 0.10 0.2 56.3 56.7 0.21 2038.88 POND-2 Version: 5.15 SIN: 1295160123 Page 5 EXECUTED: 05-24-1995 11:27:45 Pond File: C:/PONDPACK/REN6 PND Inflow Hydrograph: C:/PONDPACK/REN6 .HYD Outflow Hydrograph: C:IPONDPACK\REN6P HYD INFLOW HYDROGRAPH ROUTING COMPUTATIONS TIME INFLOW I1+I2 2S/t - 0 2S/t + 0 OUTFLOW ELEVATION (hrs) (cfs) (cfs) (cfs) (cfs) (cfs) (ft) 24.700 0.10 0.2 56.0 56.5 0.21 2038.88 24.800 0.10 0.2 55.8 56.2 0.21 2038.87 24.900 0.10 0.2 55.6 56.0 0.21 2038.87 25.000 0.00 0.1 55.3 55.7 0.20 2038.86 25.100 0.00 0.0 54.9 55.3 0.20 2038.86 25.200 0.00 0.0 54.5 54.9 0.20 2038.85 25.300 0.00 0.0 54.1 54.5 0.20 2038.85 25.400 0.00 0.0 53.7 54.1 0.20 2038.84 25.500 0.00 0.0 53.3 53.7 0.20 2038.83 25.600 0.00 0.0 52.9 53.3 0.20 2038.83 25.700 0.00 ,0.0 52.5 52.9 0.19 2038.82 25.800 0.00 0.0 52.1 52.5 0.19 2038.82 25.900 0.00 0.0' 51.8 52.1 0.19 2038.81 POND-2 Version: 5.15 SIN: 1295160123 Page 1 Executed 05-24-1995 09:53:15 Multiply Hydrograph by Constant Unit HYD File: C:/PONDPACK/REN6x10.HYD Output Hydrvgraph: C:/PONDPACK/REN6 HYD Multiplier Constant: .1 TIME Unit Multiplier Output Hydrograph (hrs) Ordinates Constant (cfs) 11.00 0.00 x 0.100 = 0.00 11.10 0.00 x 0.100 = 0.00 11.20 0.00 x 0.100 - 0.00 11.30 0.00 X 0.100 - 0.00 11.40 0.00 x 0.100 0.00 11.50 0.00 x 0.100 - 0.00 11.60 0.00 X 0.100 = 0.00 11.70 4.00 x 0.100 - 0.40 11.80 7.00 x 0.100 - 0.70 11.90 11.00 x 0.100 - 1.10 12.00 40.00 x 0.100 = 4.00 12.10 71.00 X 0.100 = 7.10 -x- 12.20 41.00 x 0.100 - 4.10 12.30 17.00 x 0.100 - 1.70 12.40 14.00 x 0.100 - 1.40 12.50 12.00 x 0.100 - 1.20 12.60 10.00 x 0.100 = 1.00 12.70 9.00 x 0.100 - 0.90 12.80 8.00 x 0.100 = 0.80 12.90 8.00 x 0.100 = 0.80 13.00 7.00 X 0.100 0.70 13.10 6.00 x 0.100 0.60 13.20 6.00 x 0.100 0.60 13.30 6.00 X 0.100 = 0.60 13.40 6.00 x 0.100 = 0.60 ` 13.50 6.00 x 0.100 - 0.60 13.60 5.00 x 0.100 0.50 13.70 5.00 x 0.100 = 0.50 13.80 5.00 x 0.100 - 0.50 13.90 4.00 x 0.100 = 0.40 14.00 4.00 x 0.100 - 0.40 14.10 4.00 x 0.100 = 0.40 14.20 4.00 x 0.100 = 0.40 14.30 4.00 X 0.100 = 0.40 14.40 4.00 x 0.100 = 0.40 14.50 4.00 x 0.100 = 0.40 14.60 4.00 x 0.100 - 0.40 14.70 4.00 x 0.100 = 0.40 14.80 4.00 X 0.100 - 0.40 14.90 4.00 x 0.100 = 0.40 15.00 4.00 x 0.100 - 0-.40 15.10 4.00 x 0.100 = 0.40 POND-2 Version: 5.15 SIN: 1295160123 Executed 05-24-1995 09:53:15 Page 2 Multiply Hydrograph by Constant Unit . HYD File: C :1PONDPACK\REN6Xi0 . HYD Output Hydrograph: C:1PONDPACK\REN6 HYD Multiplier Constant: .1 TIME Unit (hrs) Ordinates 15.20 4.00 15.30 3.00 15.40 3.00 15.50 3.00 15.60 3.00 15.70 3.00 15.80 3.00 15.90 3.00 16.00 3.00 16.10 3.00 16.20 3.00 16.30 3.00 16.40 3.00 16.50 3.00 16.60 3.00 16.70 3.00 16.80 3.00 16.90 3.00 17.00 3.00 37.10 3.00 17.20 3.00 17.30 2.00 17.401 2.00 17.50 2.00 17.60 2.00 17.70 2.00 17.80 2.00 17.90 2.00 18.00 2.00 18.10 2.00 18.20 2.00 18.30 2.00 18.40 2.00 18.50 2.0]0 18.60 2.00 18.70 2.00 18.80 2.030 18.90 2.00 19.00 2.00 19.10 2.00 19.20 2.00 Multiplier Constant x 0.100 X 0.100 X 0.100 X 0.100 x 0.100 x 0.100 X 0.100 X 0.100 x 0.100 x 0.100 x 0.100 X 0.100 x 0.100 X 0.100 X 0.100 X 0.100 x 0.1070 x 0.100 x 0.100 X 0.100 x 0.100 x 0.100 x 0.100 X 0.100 X 0.100 X 0.100 X 0.100 x 0.100 X 0.100 X 0.100 X 0.1030 x 0.100 x 0.100 x 0.100 X 0.100 x 0.100 x 0.100 x 0.100 X 0.100 X 0.1007 X 0.100 Output Hydrograph (Cfs) - 0.40 - 0.30 = 0.30 = 0.30 = 0.30 = 0.30 0.30 0.30 - 0.30 = 0.30 = 0.30 0.30 = 0.30 0.30 = 07.30 0.30 = 0.30 = 0.30 = 0.303 - 0.30 = 0.30 = 0.20 0.20 = 0.20 = 0.20 0.20 = 0.20 0.20 0.20 0.20 - 0.20 = 0.20 = 0.20 - 0.20 = 0.20 0.20 0.20 0.20 = 0.20 0.20 = 0.20 POND-2 Version: 5.15 S/N: 1295160123 Executed 05-24-1995 09:53:15 Page 3 Multiply Hydrograph by Constant Unit HYD File: C:/PONDPACK/REN6Kl0.HYD Output Hydrograph: C:/PONDPACK/REN6 HYD Multiplier Constant: .1 TIME Unit Multiplier Output Hydrograph (hrs) Ordinates Constant (cfs) 19.30 2.00 x 0.100 = 0.20 19.40 2.00 x 0.100 = 0.20 19.50 2.00 x 0.100, = 0.20 19.60 2.00 x 0.100 - 0.20 19.70 2.00 x 0.100 = 0.20 19.00 2.00 x 0.100 - 0.20 19.90 2.00 x 0.100 - 0.20 20.00 2.00 x 0.100 = 0.20 20.10 2.00 x 0.100 = 0.20 20.20 2.00 x 0.100 = 0.20 20.30 2.00 x 0.100 = 0.20 20.40 2.00 x 0.100 - 0.20 20.50 2.00 x 0.100 - 0.20 20.60 2.00 x 0.100 = 0.20 20.70 2.00 x 0.100 = 0.20 20.80 2.00 x 0.100 - 0.20 20.90 2.00 x 0.100 0.20 21.00 2.00 x 0.100 = 0.20 21.10 2.00 x 0.100 - 0.20 21.20 2.00 X 0.100 0.20 21.30 2.00 x 0.100 = 0.20 21.40 2.00 x 0.100 - 0.20 21.50 2.00 x 0.100 - 0.20 21.60 2.00 x 0.100 - 0.20 21.70 2.00, x 0.100 = 0.20 21.80 2.00 x 0.100 = 0.20 21.90 2.00 x 0.100 = 0.20 22.00 2.00 x 0.100 = 0.20 22.10 2.00 x 0.100 - 0.20 22.20 2.00 x 0.100 = 0.20 22.30 2.00 x 0.100 - 0.20 22.40 2.00 x 0.100 = 0.20 22.50 2.00 x 0.100 = 0.20 22.60 2.00 x 0.100 = 0.20 22.70 2.00 x 0.100 = 0.20 22.80 2.00 x 0.100 - 0.20 22.90 2.00 x 0.100 = 0.20 23.00 2.00 x 0.100 0.20 23.10 1.00 x 0.100 = 0.10 23.20 1.00 x 0.100 - 0.10 23.30 1.00 x 0.100 - 0.10 POND-2 Version: 5.15 SIN: 1295160123 Page 4 Executed 05-24-1995 09:53:15 Multiply Hydrograph by Constant Unit HYD File: C:rPONDPACK/REN6X10.HYD Output Hydrograph: C:\PON DPAC K\REN6 HYD Multiplier Constant: .1 TIME Unit Multiplier Output Hydrograph (hrs) Ordinates Constant (cfs) 23.40 1.00 x 0.100 = 0.10 23.50 1.00 x 0.100 = 0.10 23.60 1.00 x 0.100 = 0.10 23.70 1.00 x 0.100 0.10 23.80 1.00 x 0.100 - 0.10 23.90 1.00 x 0.100 0.10 24.00 1.00 x 0.100 = 0.10 24.10 1.00 x 0.100 0.10 24.20 1.00 x 0.100 - 0.10 24.30 1.00 x 0.100 = 0.10 24.40 1.00 x 0.100 - 0.10 24.50 1.00 x 0.100 = 0.10 24.60 1.00 x 0.100 0.10 24.70 1.00 x 0.100 = 0.10 24.80 1.00 x 0.100 = 0.10 24.90 1.00 x 0.100 = 0.10 25.00 0.00 x 0.100 = 0.00 25.10 0.00 x 0.100 - 0.00 25.20 0.00 x 0.100 = 0.00 25.30 0.00 x 0.100 = 0.00 25.40 0.00 x 0.100 - 0.00 25.50 0.00 x 0.100 = 0.00 25.60 0.00 x 0.100 - 0.00 25.70 0.00 x 0.100 = 0.00 25.80 0.00 x 0.100 = 0.00 25.90 0.00 x 0.100 - 0.00 Quick TR-55 Version: 5.45 SIN: 1315450151 Page 1 Return Frequency: 50 years TR-55 TABULAR HYDROGRAPH METHOD Type II. Distribution (24 hr. Duration Storm) Executed: 05-24-1995 09:48:51 Watershed file: --3 C:/PONDPACK/RENS MOP Hydrograph file: C:\PONDPACK\REN5K10.HYD Ridgemont Estates North 5th Addition » Input Parameters Used to Compute Hydrograph CCCC Subarea AREA CN Tc * Tt Precip. Runoff Ia/p Description (acres) (hrs) (hrs) (in) (in) input/used - Basin A @ 10x 104.40 70.0 0.10 0.00 2.50 0.50 1.33 .33 * Travel time from subarea'outfall to composite watershed outfall point. I Subarea where user specified interpolation between Ia/p tables. Total area = 104.40 acres or 0.1531 sq.mi Peak discharge = 71 cfs >>>a Computer Modifications of Input Parameters <c<c< Input Values Rounded Values Ia/p Subarea Tc * Tt Tc * Tt Interpolated Ia/p Description (hr) (hr) (hr) (hr) (Yes/No) Messages Basin A @ 10x - 0.10 0.00 Yes - * Travel time from subarea outfall to composite watershed outfall point_______ Tc & Tt are available in the hydrograph table s. Quick TR-55 Version: 5.45 SIN: 1315460151 Page 2 Return Frequency: 50 years a TR-55 TABULAR HYDROGRAPH METHOD Type II. Distribution (24 hr. Duration Storm) Executed: 05•-24-1995 09:48:51 Watershed file: C:\PONDPACK\REN6 .MOP Hydrograph file: C:\PONDPACK\REN6X10.HYD Ridgemont Estates North 6th Addition Summary of Subarea Times to Peak cc<r Subarea Basin A @ 10x Composite Watershed Peak Discharge at Composite Outfall (cfs) 71 71 Time to Peak at Composite Outfall (hrs) 12.1 12.1 Quick TR-55 Version: 5.45 SIN: 1315460151 Page 3 Return Frequency: 50 years TR-55 TABULAR HYDROGRAPH METHOD Type TT. Distribution (24 hr. Duration Storm) Executed: 05-24-1995 09:48:51 Watershed file: C:\PDNDPACK\REN6 MOP Hydragraph file: C:\PDNDPACK\REN6X10.HYD Ridgemont Estates North 6th Addition Composite Hydrograph Summary (cfs) Subarea 11.0 11.3 11.6 11.9 12.0 12.1 12.2 12.3 12.4 Description hr hr hr hr hr hr hr hr hr Basin A @ lox 0 0 - 0 - - 11 40 71 41 - 17 14 Total (cfs) - 0 - - - 0 - 0 11 40 71 - 41 17 14 Subarea 12.5 12.6 12.7 12.8 13.0 13.2. 13.4 13.6 13.8 Description hr hr hr hr hr hr hr hr hr Basin A@ lox 12 10 9 - 8 - - 7 6 6 5 5 Total ( cfs ) 12 10 9 - 8' 7 6 6 5 5 Subarea 14.0 14.3 14.6 15.0 15.5 16.0 16.5 17.0 17.5 Description hr - hr hr hr hr hr hr hr hr Basin A@ l Ox 4 4 4 4 3 - 3 - - 3 3 2 Total ( cfs ) 4 4 4 4 3 - 3 3 3 2 Subarea 18.0 19.0 20.0 22.0 26.0 Description hr hr hr hr hr - Basin A@ 10x 2 2 2 2 0 Total (cfs) 2 2 2 2 0 Quick TR-55 Version: 5.45 SIN: 1315460151 Page 4 Return Frequency: 50 years TR-55 TABULAR HYDROGRAPH METHOD 't'ype II. Distribution (24 hr. Duration Storm) Executed: 05-24-1995 09:48:51 Watershed file: --3 C:/PONDPACKXREN6 MOP Hydrograph file: --a C:1PONDPA+CK/REN6X10.HYD Ridgemont Estates North 6th Addition Time Flow Time Flaw (hrs) (cfs) (firs) (cfs) 11.0 0 14.8 4 11.1 0 14.9 4 11.2 0 15.0 4 11.3 0 15.1 4 11.4 0 15.2 4 11.5 0 15.3 3 11.6 0 15.4 3 11.7 4 15.5 3 11.8 7 15.6 3 11.9 11 15.7 3 12.0 40 15.8 3 12.1 71 15.9 3 12.2 41 16.8 3 12.3 17 16.1 3 12.4 14 16.2 3 12.5 12 16.3 3 12.6 10 16.4 3 12.7 9 16.5 3 12.8 8 16.6 3 12.9 8 16.7 3 13.0 7 16.8 3 13.1 6 16.9 3 13.2 6 17.0 3 13.3 6 17.1 3 13.4 6 17.2 3 13.5 6 17.3 2 13.6 5 17.4 2 13.7 5 17.5 2 13.8 5 17.6 2 13.9 4 17.7 2 14.0 4 17.8 2 14.1 4 17.9 2 14.2 4 18.0 2 14.3 4 18.1 2 14.4 4 18.2 2 14.5 4 18.3 2 14.6 4 18.4 2 14.7 4 18.5 2 Quick TR-55 Version: 5.45 SIN: 1315460151 Page 5 Return Frequency: 50 years TR-55 TABULAR HYDROORAPH METHOD Type 1T. Distribution (24 hr. Duration Storm) Executed: 05-24-1995 09:48:51 Watershed file: C:/PONDPACK\REN6 MOP Hydrograph file: --3 C.\P0NDPACK\REN6X10.HYD Ridgemont Estates North 6th Addition Time Flaw Time Flow (hrs) (cfs) (hrs) (cfs) 18.6 2 22.4 2 18.7 2 22.5 2 18.8 2 22.6 2 18.9 2 22.7 2 19.0 2 22.8 2 19.1 2 22.9 2 19.2 2 23.0 2 19.3 2 23.1 1 19.4 2 23.2 1 19.5 2 23.3 1 19.6 2 23.4 1 19.7 2 23.5 1 19.8 2 23.6 1 19.9 2 23.7 1 20.0 2 23.8 1 20.1 2 23.9 1 20.2 2 24.0 1 20.3 2 24.1 1 20.4 2 24.2 1 20.5 2 24.3 1 20.6 2 24.4 1 20.7 2 24.5 •1 20.8 2 24.6 1 20.9 2 24.7 1 21.0 2 24.8 1 21.1 2 24.9 1 21.2 2 25.0 0 21.3 2 25.1 0 21.4 2 25.2 0 21.5 2 25.3 0 21.6 2 25.4 0 21.7 2 25.5 0 21.8 2 25.6 0 21.9 2 25.7 0 22.0 2 25.8 0 22.1 2 25.9 0 22.2 2 22.3 2 Quick TR-55 Ver.5.45 S/N:1315460151 Executed: 09:47:08 05-24°1995 Ridgemont Estates North 6th Addition RUNOFF CURVE NUMBER SUMMARY Subarea Description Basin A @ 10x Area CN (acres) (weighted) 104.40 70 Quick TR°55 Ver.5.45 S/N:1315460151 Executed: 09:47:08 05-24-1995 Ridgemont Estates North 6th Addition RUNOFF CURVE NUMBER DATA Composite Area: Basin A @ 10x AREA CN SURFACE DESCRIPTION (acres) pavt. 3.50 98 grass 100.80 69 COMPOSITE AREA y 104.40 70.0 ( 70 ~ ~l~G~~or~~ ~5"CF~~►~~ ~la[c~H AAU~~~~l-~ tdo. I~7i~ RGA a,t~ AcE kV T. lrw~ EWlvy +z~ lS QQ 0 2 1 f `T 2 D ~ASS 3rl Fr C].t~ Ac~F- ESTATES Nol`TIN rTlf A,DD►T io W No, 12~► 6 5/4145 $AS_IN STDFA,6 UIRED _a~ "2D~" -..S'~oro~oJe 2 ((o~`t'26 ~T2) ~21N, z 2(08 ~T.= k?- lw/f I) 5oWS t.6v►oJ.. i- FT•~ -t- 1?c, k p- ~A~'r eL ~rywell (►-o cis o"T) SI oF- ACaS ?PzmIDe D C22'~` 1 (24.11 ~•6~~) 3lol f'f3 7 2~O~ 4 52 ~'C3 i 4 34 ~L -__a ,A 4 i 4 _ 'al ZO ~ '2?-At IK- r- v' l ..Z 2 Zo-25.4._. ' 21 + 3z.4 ' . . . Z _ . Z 22. ~ 2 9 1 FAA TIONAL FORMULA HYDROLOGY DATE = 4/24/95 DESIGNER = M, W I"IL;i"IULJ'II'4 BASIN "A" PROJECT NAME = R. E . NORTH 61-H ADDITION DESCRIPTION = O TORMWA TER DRAINAGE SUBAREA 1 = .219 ACRES SUBAREA 2 = .89 ACRES 1"01"AL AREA 1. -f3 ACRES OVERLAND FLOW VALUES ct = .1O L = Cj N - .4 S . 01 CHANNEL FLOW VALUES L - 1 i1 = .1I-' Z2 _ 36 N .016 B - 0 S - .026 I -D = . l e36 COMPUTED VALUES DUR = 15. f'0 010 - 1.8 - OA - 1 . B3 SUBAREA 1 RtJNf_1F"F COEFFICIENT = . t? SUBAREA RUNOFF COEFFICIENT = .15 COMPOSITE RUNOFF COEFFICIENT = .41d-O4E 47026 Dri-CE - 4/2-4 /95 DESI GNER K W MCMULVIN EASIN "A" PROJECT NAM = E r . E. -ION NORTH 6TH ADD I T DESCRIPTION = 5TDRMW ATER DRAINAGE- t t Intensity udev. Viii Vai-It Staraqe Oyan. 5 (soc. (in. /t'r. ) (CU. +k. ~ ICU. +t. } (CU. -Ft. y 5.0 7fc 'c'1Cl . 1 B 1 . 6 _i 7:.,4 v.f_I[ 1 -1-14 10. U 600 2.24 1.29 9[.).:, 600 10 1 15. 0 90f,) 1.77 1 . 0-2 1 C) 19 900 119 20. 0 122.)0 1.45 . 6~ 1 Q 6 15 1 '2100 -1 15 25. o 150C) 1.21 .70 r 1114 1 5uCl - =;56 0 1800 1.04 .60 117. 6 1800 - 664 X 5. [ 1 210 C.) .91 .52 1 151 2100 --949 40.0 400 .82 .47 1 179 2400 ] 221 45. C} 2700 .74 .4 1 191 2700 09 --1-1$ 50. 0 7-000 .69 . 7~9 1212 7000 --1768 55. 0 :..700 .64 . -37 1:951 :3100 .sZ69 60.0 =,600 .61 . _ , i 1297 a600 -2 :7101 65. Cl 7.900 . 60 _74 1 ',60 w~9f.}f.' 70.0 L1200 .58 L 1~E_ 11~ 75.f.) 4500 .56 ..'2 1467 453.}f:l 60. 0 4£00 .53 . ; Cl 1493 48(-X) 3.)7 B5. Q 5100) .52 0 15 _19 1 i:lC } - •;J fa 1 90.2-1 5400 .50 .29 1580 540Cl 9 5. 5700 .49 .20 16;7, 5700 --4067 100. [1 6000 .46 . ~8 16BL 6000 -4717 THE t A)CI MUM STORAGE IS A ti 4.4176? CU. FT. The time of concen tration 15 5 ml nUtf-5. The Undevel oped + 1 ow out is 1 c. f. s. TEN YEAF( ST ORM CALC RATIONAL F=ORMULA HYDROLOGY DATA. = 4/ 4 /95 DESIGNER = F; W MCMULK I N BASIN "A" PROJECT NAME = R.E. NORTH 6TH ADDITION DESCRIPTION = PAVT. SUBAREA 1 = .49 ACRES SUBAREA 1 RUNOFF COEFFICIENT = TOTAL AREA = .49 ACRES COMPOSITE RUNOFF" COEFFICIENT OVERLAND FLOW VALUES Ct - .15 L - Q N - .4 CHANNEL F=LOW VALUES L = 315 Z1 = .172 Z2 = 36 N - .016 B - a S _ .026 TD = .166 COMPUTED VALUES DUR = 5. 00 110 = -S.12 010 = 1.40 OA - 1.40 Curio D~~~.i1na~ Oh C4h~i+nuO~S GY'0.at. = 1.40 ~-fs bes io~v. 17 isc~hc~~ ~e .9 .9 ~ ~ (7.105 ~t~a+nn ~ l a~. 1~, {w} a fig. ~S - 3`d 44 y P~F~h~ Caun~i u tau+c~~li~re,5 A- ~or S~ o'r~mw0.~~r Nlrav.~~e,vne,~. Q 1.40 t3.?> { Q'a'A' o . t 05 r SAY flpe~ri►n~ ~ 14 wtid~. , $IA c~e~p e DEPTH OF FLOW - y - FEET- 0.166 01 .02 .03 .04 .05 06 Oa .10 2 .3 4 a .5 6 .7 .8 .9 to r ~ f ~ I 11 I r l I; - 4--9 - Ty - -r-E -I I ' L I ~ ( , ~ T t. - - 14-1 ~ I ~ A l i r ~I ' f I r ~~i I l 40 1I; I- gorl ~ I' I 1 { I I I I ~ I ~ - ~ Z' f 17. i 6 l 1 I i li l~l ~ d i I I I C I I ~ III f ~ l~f' . I l I 16 I C I f r 1- I I~ I ~ ~ I I 1 ;I ~~II~II I I ~ ---~t-- I~ I~~~ I I . I I~ I I I I I 1 1 1 .or _ k i (a) DISCHARGE PER FOOT OF LENGTH OF CURB OPENING - INLETS WHEN INTERCEPTING 100% OF GUTTER FLOW (b) PARTIAL INTERCEPTION RATIO FOR INLETS OF LENGTH LESS THAN La 10 .8 6 .5 .4 3 .2 a La x~ 0. l a 1 ,10 0s .06 i .0s 04 I i .43 I .02 1 i i _ I 10 a a s ' 4 , O 3 Q 0 2 10 .05 06 08 10 2 3 4 7 .6 8 10 L/La CAPACITY OF CURB OPENING INLETS ON CONTINUOUS GRADE 5-39 FIGURE 16 g1~G~MDh17- P,5YA'7 C-5 Nn~'~k1 ~-[t~ ~Dg k7LItC, DRAGE CALCk] -[i'TiioRs ~f l?5 W M - . . _.`~r, x_45 . _ ~ • 4 4 ~,G~E FT, ~°~v~=AGUE 3 - - -----~~---~aw-5-~r~i_,~g_~-__~ ~_._Cj__.~E~C~__ ~....._1----~ s,~~t~.`$a~r~.l ~r~w~.E4- - Z 10 V1. 01 4 21 RATIONAL FORMULA HYDd--1OLOGY BATE = 5/5/95 DESIGNER = K W MCMULK I N PROJECT !'JAIME R.E. NORTH 6TH ADDITION DESCRIPTION = STORMWATER DRAINAGE SAS! N "n'• SUBAREA 1 = .04 ACRE: SUBAREA 1 RUNOFF COEFFICIENT = SUBAREA 2 = .07 ACRES SUBAREA { RUNOFF COEFFICIENT TOTAL AREA = . 1 1 ACRES CC]MP051 `i°E RUNOFF COEFFICIENT = OVERLAND FLOW VALUES Ct - .15 L ^ 0 N 016 S CHANNEL FLOW VALUES L ^ 95 Z I = .172 Z = -T6 N - .016 B = 0 S _ . c.f1H TO = .0766 COMPUTED VALISES OUR - 5.00 110 - 3H IS 010 _ . 15 CAA •I~ c r'b oper~Nh5 oy~ Covk- i Au' ous (Sr-o Ae z D.l~r ~IoWia~e ae~~es~aa„ 0A nFe.+n►r\9 D.0- ((o' L7~p~In 6~ -Flow ih no~rw~o.l ~w~ter Q p.15 CA A-s desjyk 0, z X7.01&1 Lq a Q aC-/uw .9 .15 .422727272727 ~C'r~+N► frig. 1G (-39 "sv0-'o0Ae co\AV%A' 6~A q %Ynes ~o~ SCI v~cw.wr~.~er ~r.~~a~ernea~ ~715 Y ! B OWSTRING CALCULA T I C3N5 BATE = 5/5/95 DES IGNER = K W MCNULKIN BASIN "A" FROJECT NAME = R. E . NORTH 6TH ADDITION DESCRIPTION = STORMWATER DRAIN AGE t t Intensity Qdev. Vin YOUt Staraga tsT,in.) (sec.) (in. /hr. ) (c.+. S.) (CU. ft.) 4CU. f t.) (CU. ft. ) 5. 5 ~.7 r :17. 18 . 1'~r 59 VC-) - a 1 10.0 600 2.24 .10 77 180 -107 15.0 900 1.77 . C a 62 27x.; -18€3 20.0 1200 1.45 .07 Ba : :560 -272 25.0 1 500 1.21 .06 0 . 45CI -Z.60 30.0 1800 1.04 .05 92 540 -448 7.5. 0 2100 .91 .04 971 630 _517 40.0 2400 .8'? .04 95 /20 °-625 45. C.) 2700 .74 96 8 1 C) --714 50. 1000 .68 . C)` 98 900 -802 55. 0 3300 .64 , Cr 101 990 --BS9 60.0 3600 .61 .0- 105 1080 -97 65.0 Z1900 . 60 , 0 3 1 1 1 1 1170 _1059 70.0 4200 .58 .02, 116 1260 -1 144 75. 0 4500 .56 .0 3 119 1:'50 -1231 80.0 4800 .53 .0'? 121 1440 -1319 e5. 0 5100 .52. 15 30 -1405 9t_r, C) 5400 .50 .02 128 16 0 -1492 95.0 57C)0 .49 .(--)2 1712 1710 -1578 100.0 6000 .48 .02 1a6 1BOO -1664 THE MAXIMUM STORAGE IS Q CU. FT. * The time of concentration 1s 5 minutes. The Undevel aped 4 1 OW art 15 . c. f . "a. TEN YEAR STORM CALC 0, o~ G6 DEPTH OF F OW - y - FEET .01 .02 .03 .04 .05 06 a 10 .2 3 .4 # .5 a .7 8 .9 10 1 I I I t l I I I 1 I I I I it i i /0 - + - - - - - T T r I 1 T- -F 7_ _I -T j -L I I I ~_I I IJ-71 I I I I I ~I~ I I I I~ I~~j(~ I I I I I I i I 1 1 1 ~ I I ~ I ~ 1 1 1 1 1 I III ;III. I ~ I I I I. I III °o'~ ~°I 1 1 1 1 1 1 I I e ff ;o I I I I ti l l I I' ° I I I I I I I I I I I I 1 I I I I I I I I I I I I I I I I I I 1I ~ I I I ~ I ~1 I I I I I I I I I i I jt I I I IIII I I II I I I I I I IIII I I I (a) DISCHARGE PER FOOT OF LENGTH OF CURB OPENING INLETS WHEN INTERCEPTING 100% OF GUTTER FLOW (b) PARTIAL INTERCEPTION RATIO FOR INLETS OF LENGTH LESS THAN La 1.0 .8 .6 .3 .4 .3 .2 0 a La .10 .08 .06 e 0.051 -o s .04 .03 .02 I t . 01 ; 1.0 .a 6 I .s .4 Q .3 Q a 2 Io .05 .06 08 .10 2 .3 .4 .5 .6 .8 1.0 L/La CAPACITY OF CURB OPENING INLETS ON CONTINUOUS GRADE 6-39 FIGURE 16 I I I a/ - - 00, I I I I I I °6 I I ~ I I I I ~ I _ oo, o, ~ ° I ti - i_ I I I I - t. i I -L I I I I I I I I I I I I I rt I I I i_ I RUC, ~Mv rtT E 5STA T,S N v 1P.TK 6'~H PDDkTta1j NO, i L`] l6 DP~~NAGE CAL-CL] l.lrT t~N ~Z` V~ M A A, T0 ~ ~ ' ~ D i 1 FtiC 7A, . k-l IR rwee q-CAD S 5 1 15,E I T I .JLG ~t [ZOOMS °~_5 2-oDD fI DOo f-T-2- rA\ X) 9-1VF-:S z L~T=DOD iI DDD L ❑'C 1 DOQ 5 46i 61 E3 4 C- t ~edG~~IDNT G~`~AYE$ h,1p~TH ~~H ADUI°Crt]t~ N~ _ 1'I v~ DP.IN F~C~~ ~1~~CU LAT [ lJN I Z9 (:r r\N M ~ b A C R. C U.l F L> ~ Z b~' STa!~AG~._ 1.5, 612- G53 C - , _ fa).~W~lG_ (2 ~.F= e~vr j ~"CA~AG~ P~~v[vEAi. 3D.'3 G' 64- 6o Z RA-f ! C7NAL i OIi 1. 1JL_i='i E,iYDI i[.'PLO D'a PR03EEF NAME R.E. NORTH 6TH ADD., i.JLSC R II P TIi N ° - ST+JRMVd1°9 I ER DRF°tl~V~-CE r}L1~D Ai' sE= A I = 1.07 y -p ACRES r tl 9 SU E~~3°Ii"Alm A I RUNOFF d r ~e 0GF 1"7 lCi ENT w !T CUBAREA 1 = 2n ] I ACRES SUBAREA 2 RUNOFF COEFFICIENT o nk o bw C , 1 s AIri;PS C'ulFII-'owi E C ii[JE'•EOP Lt:EiE-E--lcipi•:I` OVERLAND FLOW VALUES L _ 4• N .4 rHANNEL FLOW VALUES L - `0 Z]_ ° . 37; Z2 6 F1 - .016 S 13 TD - .2655 o"]i`ii°'l i rco VALUE'S DUR 5.00 110 - L E" 010 4-m -CO) 77, on "Q4 DATE = : ''P ?4 DES A L11* EI-Q = V W 9 IC,"MUI__K Y I'd BA , t 1••1 1' i+" i `L°;€'j3EC: C MP111E = R' 1=. 1 l CR,TH 6 1"1.4 1 DD Iii-SCRIP-r f ON - STC71=;14WO TF P DR(-i -1 Nr' l3L C t I n t i- n r3 ti t y t d'T.' 1•' . V i n Lt C j E.€ { r+'t C', I, ^ i_- .i7 (Ill. /hr. y tf.°. f .s ~ Lcu. 4 t.. {[e€_€. f 1 7 °L,l • { i_.• ! . C } T; v4 tCl 1 111 E_17 167, lo.() 600 t.t"Y 2.3! 'y.'E1L~ ~E]S] C~f y 15. C) 94jr) 1.77 2a 26 2,21 9 1800 :°'4 i , (1 1 ~0 C7 1 a. L15 { Gb ~ -1~ 16 7!-4i iS 1 16 sb,j , t„'r T If) C.}C_I of i „ c l I Ono 1.04 1 , _ Ii,., J }S~1 - i F Yf- 4_l g f 1 E`70 . 9 L 1.16 _,°•f `~Srlf 2°741[1 .721 .9 5, '[~j'j? :j fElE_7 _-~r •1° `i:+~ 64 .812 27EM, ~60C,i :i_il.;. 6C?. j_} - 6070 . 61 .713 GL3L J t o-) 65 . Cl ,()C) 60 . 76 3(D14 7 7 SC_1C_i 7f) . Ci '3 0fD .511 . 7119 ,r'4nrj J-, ]I= Leo. Ci 4SOCl 60 r»~ 3i`.300 --6216 }ff~ § [ ] 41[,) + c2 . 61; ZiI TO 10200 °C 1 r 1 » 070 . 0 5400 50 64 108 0 _71130 N r=] 57C) Q x; 4'9 . 6 . 767,=3 1 1 C ]C'1 -°7 7c~ 9 THE lt--~X,Tf IU3"1 SfC3i= ASE I S, 1 C] 15. 66162 C L.1, FT The ti me n•f concen,ration z s 5 mi nut es. 1-he U n d i<~ c-21 o pev)I;4 f1, ow €3 C L r, 2 C + ca n TEN YEAR STORM CALC: RATIONAL FORMULA HYDROLOGY DATE = 10/7/94 DESIGNER = K W MCMULK I N PROJECT NAME = R.E. NORTH 6TH ADD. DESCRIPTION = STO MWATER DRAINAGE SUBAREA 1 = .--,6 ACRES TOTAL AREA = OVERLAND FLOW Ct = L N = S w .36 ACRE'S VALUES .15 .4 o1 CHANNEL FLOW VALUES L - =0f Z1 = .17? 22 = w6 N - .016 D - C~ S _ .018 TD = . 1'5 36 CL mpu rED VALUES DUR 5.00 Il() - 3.18 010 _ 1.03 QA = 1 .0-7 BASIN "B" F'AVT. SUBAREA 1 I:;,UNOFF COEFFICIENT = . 9 COMPOSITE RUNOFF COEFFICIENT = . 9 C.urAB J4'e4`IN6 Al LUW ?olr4T STA. ?1t9 W 8" Z. o.(.i' ~o~ral he 15kt o'~C ra?eniw,q Q-ks-36, ~7e ~r1n of wrier OJ cwtra ccc Q x.03 CF5 v~~l P20.v. V-xtc dJ f law 3v _ Q 3.o$O 0K~~`z 3.0 t~,Z (OA5$G) vz. [uTTSR S??EP,'D DN SOMO'g . z4 INS _ - - - - fig' - - - v.g❑ ~ - - --s o 50 .ti ~3•l~' O.IG> } O's 13x1 - - j 0. 1 1n ~i u 16 CA tea,+er 5.?~' wM D ) W OF F Eei6LOFe C) - Cox r s Y j j - D ~ 5 ~T "tia s - - ..w4_._L OTs...e.. 4 0 Z' T, _ h? r C] DG A- D-T a Fl o D =r , S s C) D cA " s ~~~~~v~~S~R~rEs NvZk~~4 AUS~. t 0. SSG P.ix~ -15 lz~D ~'Z 1 N1 T , c ~ s o "i 5 ~f F•G~ F OVII>ED : ~di ~ D . -.--_r L~;J i, mom.-_._______. ..r- _ . ~p~r _ -1 5,36 -7 RATIONAL FORMULA HYDROLOGY DATE = 4/21/95 DESIGNER = I: W MCMUL!' l N BASIN "C'k PROJECT NAME = R.E. NORTH 6TH ADDITION DESCRIPTION = STORMWATER DRA I NA13E SUBAREA 1 = .61' ACMES SUBAREA 1 RUNOFF COEFF 1 C I ENT = . 9 SUBAREA 2 = 4.34 ACRES SUBARL- A 2 RUNUF- COLFF I C I EI• T = . 15 TOTAL AREA = 4.97 ACRES CC]MPOS ] TE RUNOFF: C0EFF 1 C I EIV l- 24 507042-257.51 OVERLAND FLOW VALUES Ct = .15 L = 5:0 N _ .4 S - . 021 CHANNEL FLAW VALUES L 0 TD COMPUTED VALUES DUR = 1 1.'89 1150 = 2.B7 O 1 ~ - BOWSTRING CALCULATIONS DATE 4 /21/95 DES IGNER = K W MCMULKIN 8AaIN „C" PROJECT NAME = R. E . NORTH 6TH ADDITION DESCRIPT ION = STORMWATER DRAIN AGE t t Intensity Odev. V~ n VOUt Storage (rriin. 3 (sec.) (an. ftlr.) (c.f.s.) (cu. 4t.) (Cu. ft.) (CLAE ft. ) 5.0 30(-) 4.57 5.57 22='B 900) 3-11716 10.0 600 --1.2o 3. 90 7 17-; 4 1 BC}C) 1:1,::4 11.9 717, 2.87 -50 343 2140 120 7 15.0 900 2.45 2.98 '-74 10 700 710 20. 0 1206 1.97 2. 40 3461 X600 -1 ~ 9 25.0 1500 1.68 2. C}5 a566 4500 -91.: 4 0 11600 1.46 1. 78 7.632 540C; -1768 75. 0 .100 1. 30 s 1.56 7,709 6Z°,C}0 _2t5V 1 40.0 2400 1.18 1.44 3,798 7200 - ;402 45.0 2700 1 . C}8 1 . 32 3 871 8100 --4229 50. 0 1C.N }C} .99 1 . 1 -,[?10 9000 -5090 55.0 711300 .92 1.12 51?70 9900 - 591- ('1 60.0 36C.)Q .87 1.06 407' loec}CI -6728 65. C} 1900 . 83 1.01 4188 11700 -751'2 70. C} 4200 .79 .96 4275 12600 - 0--,215 75.0 4500 .77 .94 4448 13500 -9052 € 0. C} 4800 .75 .91 4606 14400 -9794 85. C} 51C}G .7 .89 475x} 15v(Do -10550 90.0 5400 .71 . G6 48130 16200 -1 1 Z•210 9 5. 0- 5700 .69 . 84 4994 171 CIO 12106 100. C} 6000 .67 ii2 5094 1 000C) -12906 THE MAXIMUM STORAGE I5 13,37.63651999 CU. FT. ;K The time of concentration is 11.0912".3 smi nutes. The Undeveloped flow out is 3 c.f.s. FIFTY YEAR STORM CALL - RATIONAL FORMULA HYDROLOGY DATE = 10/7194 DESIGNER = K W MCMULKIN BASIN "C" PAVT. PROJECT NAME = R.E. NORTH 6TH ADD. DESCRIPTION = STORMWATER DRAINAGE SUBAREA 1 = .24 ACRES TOTAL AREA w .24 ACRES OVERLAND FLOW VALUES Ct = .15 L - i) N - .4 S - .01 CHANNEL FLOW VALUES L = Z2 ZI = .172 Z2 _ -36 N _ .016 B - G S - .007 TD = .167 COMPUTED VALUES DUR - 5.00 T 1 s? - ~ . 1 'S 010 .69 DA _ .69 SUBAREA 1 RUNOFF COEFFICIENT = .9 COMPOSITE RUNOFF COEFFICIENT = .9 CURB 0l'~-ta1N.G A'T l-loW 'POINT 1 S` FN. 3 l t cl8.-I$ ~tl ~Lf r 0,~a'1~ ~o~~~ ~1ei~G►'~ a c~[~~Y1►na~ r 0-69 CF 5 l a-vo,1 v e. 0."(- 'C 4Ae- o f - I v w h i ~n 0,61 L 3.01&-j (09 C \.klF- > oP NItAG.1 41 wiAe- 1 5,4 8eer y~M~ CE z-rPleTs tAoiz-fti rr~~717. ziiq . i OIDY ~ 1B 13 5_.-16+ (?•1S` D •1Lo SPOKANE COUNTY Isopluvials of 50 year 24 hour precipitation in tenths of an inch. 24 26 28 22 22 30 24 26 ~t17GEMOr~T ~ ST,~T~~ K,OATH r"}, 'NVI I! FIGURE 4 Sheet 2 of 2 i 9 I r E E i E n-f SPOKA J E' COUNTY Isopluvials of IQ year 24 hour precipitation' in tenths of an inch. 20 i P G 1 i in ~I 6-6 26 26 q~,26 f E 26 '24 ?2 i147YH ~7M R9D, 20 9 i FIGURE URE 4 Sheet 1 o~ 2 Appendix A: Hydrologic sail groups 1 r f Kim Soils are classified into hydrologic soil groups (HSG's) to indicate the minimum rate of infiltration obtained for bare soil after prolonged wetting. The HSG's, which are A, B, C, and D, are one element used in determining runoff curve numbers (see chapter For the convenience of TR•55 users, exhibit A•1 Ilsts the HSG classification of United States soils. The infiltration rate is the rate at which water enters the soil at the soil surface. It is controlled by surface conditions. ,HSG also indicates the transmission rite-the rate at which the water move` within the soil. This rate is controlled by the soil profile. A(iproximate numerical ranges for transmission rates ahoxv-n in the HSG definitions were fu'st published V Musgrave (USDA 1955). The four groups are defined by SCS ;oil scientists as follows: Group A soils have low runoff potential and high infiltration rates even when thoroughly wetted. They consist chiefly of deep. well to excessively drained sands or gravels and have a high rate of ►rater transnussion (greater than 0.30 in/hr). Group B soils have moderate infiltration rates when thoroughly wetted and consist chiefly of moderately deep to deep. moder;itel►• well to well drained soils Mth moderately fine to"moderately coarse textures. These soils have a moderate rate of water transmission (0.15.0.30 in/hr). - Croup C sails have low infiltration rates when thoroughly wetted and consist chiefly of soils with a later that impedes downward movement of water and soils ►with moderately fine to fine texture. These soils have a low rate of water transmission (0.95-0,15 inlhr). Group D soils have high runoff potential. They have very low infiltration rates when thoroughly wetted and consist, chiefly of clay soils with a high swelling potential, soils with i permanent high water table, soils %dith a claypan or clay layer at or near the surface, and shallow soils over nearly impervious material. These soils have a very low rate of water transmission (0.0.05 in/hr). In exhibit A-1, some of the listed ,oils have an added modifier; for example, "Abrazo, gravelly This refers to a gravelly phase of the Abrazo series that is found in SCS soil reap legends. Disturbed soil profiles As a result of urbanization, the soil profile may be considerably altered and {he listed group classification may no longer apply. In these circumstances, use the follo►► ing to determine HSG according to the texture of the new surface sail, provided that significant compaction has not occurred (Brakenstek and Rawls 1933). RSG Soil textures A Sand, loamy sand, or sandy loam B Silt loam or loam C Sandy clay loam D Clay loam, silty clay loam, sandy clay, silty clay, or clay Drainage and bp-roup D soils Some soils in the list are in group D because of a high water table that creases a draurage problem. Once these soils are effectively drained, they are placed in a different group. For example, Ackerman soil is classified as A1D. This indicates that the drained Ackerman soil is in group A and the undrained soil is in group D. (210-VI-TR.55, Second Ed., June 1986) A-1 Exhibit A-1, continued; Hydrologic soil groups for United States soils Face$T C ! Fu45"tA: C ! GAPCOI 0 1 GEO D I Gil[SRI4 O fACCSTOme C ! FUL$"Oh C I G+PR D I Gft C 11:LLwxp C fAtflOeh 0 ! FLL IOR 0 l GAPO. GRAINEO C I GteQUAG C I &ILLeaOEA p fkeEu.T9R 0 ! 01 1.0.15 0 ! GAPP"41CR a ! &CtAORC C I GILLIAM C FAE£ICaER 1 1 FUL.AIOCA 0 1 GAPa C I GCEA 0 141LL¢4 M fAEEICIIui a l fuhltA 0 ! G+krl•R 0 1 &LCArSCN a . 1 GILLS a C FaC45au&G O 1 fUOUAT f 1 C•AACO 0 I CffO A ! GILL56URG C FAfROhT C I fUAhls$ ' 0 1 CAR OUTT a 1 &11544 L ..a 1 CIL rRta n l fu.ISAUA 0 1 G+FCtha C ! Gege C . I LIL.OAE a C fAcaCM C I f6"T ~ 0 1 GAACf$ G ! GCLRIC L I 61LI•.0 q ffrEti[nCAC(X 0 1 tURT. ORiINfp C I CAACI■ C 1 (tm C I GILFIN C foe NC h,001" C i fu1.4j41n♦ C I G+tIC IIAS C 1 GEA. S1OaF G I &1LROr [ fA£xCnaaN p l fu4mvafi C 1 &.ACON [ i GCMID C I GILSIOa fR9xCnfQw11 O .I G+A67gA C ! GAACCLLF• O d &LaSDa 11 P GILT EACC e 0 fI- r Sn641Cil O I C.AA630W A I LPRCLn+ P 1 GLMaw O k GIMLET] f - - p I GAaas C ! GrNO ixCP A 1 &caCCRAf 0 1 Gla..f 0 p b LI,4 •LFaL I I G+0aTAL4Y 0 1 GFROO+fRrS F0r¢ b I &Chf..5Ct x 1 Giatx FAesftoaq. TnICIr O C I G.DsL [ I GARD"IftyIL69 C I &EaeTa 0 1 61a6ER p 0 S LUO 04Eea I 4AliICt G+~FOGMt I • I &£h0a C I Glnl 4 FRf tRIK d a 16•bin0 I &ACLT 1 GAAt r p 1 Gt:n OLa 0 ! 4lalaa8 A FRI.ipA 0 1 GACM&Op C P 1 LARraN I GaRFIfLp ! [ I GeaI1LLT A I LI aw 1 5 C fAlw%l 0 ! G+L IAA 1 44iWiLL ! 0 I GLnFAY &LOCOnD■ 0 1 &lasfR C rRIOLO e G+OAES 1 C GARIPCR I £CnAf1C& C 0 I GIRARD 1 &!o•r.AOT O FA 1t DLAx D461 F L I.4&aO11 A 14,461 T+ e 1 GCORGf C4LLrC O 141AA a ACED -14 Filf"OS C l GaOSOty C I GFRLAaO C! C9OAGC10.a O I Gls1 a D fAI::aOyn Ip C J LAASpE~I. LCT C I &AALfT C! LtOA&LTILLE D I G! I •LuP [ FAIE5 • 1 _ SLQS I9 ~r Uri 1 &orll OCll O I GLOAGIA C 1 Gll Aa p FQIr5LA40 7 IS I fA09tLL ! Ga&COT C I G+h$1VN ' C ! LCPfCAO C I L1.1n C •e. I JC4CS O i, B I GARKDRf a ! LfF+p a PCpCeE I F.71v04C C I LaGIL r 1 GfAatL C ! Lfi•HE61 C I CL-00th n FRIxCi C 6 Gar~Ct ' r ' ! G.anfA p E GEPwtA D I 1;6 refl O FRIO L ! G+lF t 1 G+AMm: E I GCRffA 0 ! GL.Of TILL£ O 01,417/.,4 C ! GAILA O I G+hO G 1 GLODAV" 0 164.PC►.1tR A 0a FRL3T L I Galht6, 4 C 1 GwRR I LaLRfTSO'r P 1 ' 4fGIhG r l &L apSrCat C FAIAP L 1 G.Ing57CkO C! Gm0AI11 1 1 . 61ALACI+ 0 I GL►A.IN t FR[:CO 0 4 C.Al&CSrILLC t Cl RLawf L I GL•SGO. FA LS! IC d ! &.LAra A 1 p GAI3q tSJM C _t~ I CfQLC a I CLFSS^LA G I &.LOAeTH 1 CAARO naL.S 0 ! GdQ:Xw T0vN L I GLt AN L FAILICLL { GaLCMUl1 7 I C I G401 10 GAPICN ! ! Gt6..t.T f ! GLFaSOn a PG P I GALL C I &f0McA C I LLCOC C FRGOD G.L[h n! &Awvf1Qh C I G.A ONI t l'GLEN L F AO+..wq C G.4taa1 0 1 6aFr In D ! LfCA►RO L &L ! t p11Aa 11 p ~ I G.Ltsrlp+ 0 l C GAA0.IR arpl 'GERRARD. OA+iaCO t i GIf. rE7 C f7LIC. C l 6aLf$17Tr. 1 A ! 4:01* Pent ~ & f 1 O ! &tdml GE A I CLenaC6& b ~4ET.rlplrtseDS ! G.LtT a I Las C6LE[ S SSIL e ! 6LtxOLwIA e •AOLIC. FL00OCn Ir CAL I L C I &+6C('aA0v G ! 0 G[SiarES Po DI CL'.h"0GX 0 f4Oar14Ri b I Gw61 SfD $ C °I 4AS14 1 GtSIRlR n ! "'nC A 1,0 L FAGAIEaAC 7 1 G.LISrCO. C I . L&K6rT r l y &FIAmAr O 1 GL£hC+AO. ►ET. C 0130.00 ICa• - C I S+LIM:•.LIC►L1 1 001$$+7aT I p ccIcmcw. C I S.47hf +0tit0• ' O I a .46AxU C I AS%VILLt 1 C GE7Ka14 0 1 &4Chcaf boo fA :S7 7 C I LA}1071 ! C GET ITS C ! 41.9aCrIe. POx0t0 0 FAOLwA6 C I L•LLCGOS C I GAr 1 ° Gf TIY1LLC 0 1 GLiNG4Lf a F4U1 TA a I LaLL9k C I GAIt'J I LLwrL6 C I &LLnDALC. ET C FAiJI TFIELD • I GA4LIA $ F l Gf 7Stn C I CLfhO.LC. RAAELT C F A' UIImure SI _ C d LAL4. S y! a I IE■ C41Cr I GIOaLCA G C ! FLOG OtO FAUIILARO 4 1 &ALLIDM 1 I boom O I GLEaOfA$Ox L FGUITLaxO. [ I,L.LLi.FY A ! n I GATE►FT ' ~+rfTntsc C ! GIOOGaSCREEK C l GLEsD1rC n ~GO:o.rt♦.T WLr I &A4.41IP 9r I GwIL14 C I GILDS 0 I C4tkQCkA FQUITL aKO. WCF C 14•L V0 [/DI GaTgk O 1 LltatT C I CLthfofft p fATf C I L.Lr P 1 610".1vi61,L 0 ! 6LIaf4C q f .FSUAL 7 1&+41'. O 1 f l GAT►r'a G+ULPT 1 I GICVCLL L 1 GLLaFOAp C 01t1. elA Ur C I GLL rf5 mi. ■ 1 G+U4 tj C 1 G C 1 44 Ean+LL A F1. GR€Ea 7 ! G+4 r:l ! G+weL IE LO. C I GLe M.w• a FUAAA G I G+LTIh ! GAY14Ap C! GIfFGAO 4 I GLCh••r 0 Ful'plf D I &4ti 4aY b ! GwY I m's C I GIGGC0 C ! CLEW- A G fUC61 L ! GA9FLEA 0 I G~TlplA 0 1 0 1 GLL+ 0 a ! LL C FufGOST• p, 1 GvrAG. a• I GAT GILaERT P I-OP& ! CLLhp 0 FUERA C I GA 64f C l G+T4tSTILL~ boad 0 GILAOA 13 1 &LtaP06L A +UGa.f f 4 1 GAaA00 D I _ GA TL U149 1 C G1LOT O l 6LEMWG O FU G++fm C I G+xCC 1 G16c"OLSr A 1 "ChA 014 4 F UL[htA C 14.aA11 G i 413THIL4 C L I O GLLCO b 1 66EwAOSm fULOA E/O &aais 1 0 ! . GAlf LLC ! GILCAE57 a l "Efts Ito p FVLLA- C I GwhhCTT A! GAA04 A ! L161Adz C l 4LCh10q ° • 0 I 1.aa51+d°.A C ! GAtI1FL4 C I G1Lf5 a I GLCMIGN. ■f T C F UL L. C A 0h I It l G.nS.rLA. POaptC P l GLAC"Am F C I GILFORO nJl+ l GLt"10Sn " FULaeR D I G.rl1 0 1 &CAAT ' I GILT A I GLCn►if■ e fULAFA. AAAIhEp C ! GaPSUIrC O ! LCnT GeS a l O 1 011F SIA1C0 s 1 GLfa1lILLE C uOSTRATUa. ! GLEI1Da I t t + . / OFFICE OF THE COUNTY ENGINEER SPOKANE COUNTY, WASHINGTON TO: Jeff Forry, Department of Buildings FROM: Bill Hemmings DATE: Monday, April 15, 1996 SUBJECT: B.C.C. resolution # 91-0882 Implementation (JULY 2, 1991) Attached are the individual lot plans for each lot containing a swale in RIDGEMONT EST NORTH 6TH ADD,plat# P-1684E. Please give the appropriate lot plan to the individual applying for a building permit on the lot, so they can draw their house and approach to scale on the lot. We will need this plan, and the corresponding $1000.00 cash surety, in the form of cash, letter of credit, or savings assignment, before we can issue the approach permit. Also attached are the letter of credit and savings assignment farms, kldVU08pri 2196 "AGREEMENT" In consideration of the issuance of a building permit for Lot , Block , RIDGEMONT EST NORTH 6TH ADD (plat) plat # F 1684E (Developer) has deposited $1,000.00 with Spokane County as security for full and faithful performance by Developer respecting certain drainage facilities and sod in accordance with the drawings and specifications as submitted to and approved by the Spokane County Engineers Office on (date) 199 Developer hereby agrees that should such drainage facilities and sod not be constructed in accordance with the approved drawings within six months of occupancy, Spokane County may then use the security to bring these facilities and sod into conformance therewith. Developer shall be responsible for any costs incurred by the county in excess of the amount of security. Spokane County agrees to return to Developer any unused funds upon satisfactory completion of these facilities and sod. NAME & ADDRESS TO BE RETURNED TO: (Developer Signature) DATE kld\f1208pri 2196 For security purposes only, (developer) hereby assigns to SPOKANE COUNTY, a political subdivision of the State of Washington, the following: Savings Certificate Number in the face amount of $1,000.00 and field in and by Bank of Branch (bank address) This assignment is made as security for the full and faithful performance by (developer) of certain drainage facilities and sod for LOT BLOCK-, RIDGEMONT EST NORTH 6TH ADD(Plat) Plat 9 P 1684E in accordance with the drawings: and specifications as submitted to and approved by the Spokane County Engineers office on (date) , 199 Any interest benefits accruing under said savings certificate shall remain the property of . (developer) Said savings certificate to be released to (developer) any other party only with the prior written consent and agreement of Spokane County PROVIDED, FURTHER, the undersigned does hereby authorize (bank) to pay over to Spokane County all or a sufficient portion of the monies in the savings certificate referenced hereinabove upon written documentation being received from the Spokane County Engineer indicating that the purposes for which the savings certificate was assigned have not been fully and faithfully performed as required and a statement of that amount of money which the County Engineer as required and a statement of that amount of money which the County Engineer deems necessary to complete such obligation. Upon receipt of such written documentation, (developer) hereby authorizes (bank) to release to Spokane County that amount of money requested up to the maximum amount in the savings certificate. of security. (developer) shall be responsible for any costs incurred by the county excess of the amount DATED this day of , 199. BANK OF STORMWATER DRAINAGE CALCULATIONS FOR RIDGEMONT ESTATES NORTH 6TH ADDITION October 12,.1994 Prepared by= Simpson Engineer's, ' Inc. North 919 Argonne Road Spokane; Washington 99212 RECEIVED J U N 0 6,1995 TABLE OF CONTENTS SPOKANE COUNTY ENGINEER I. Summary II. S'torrnwater Drainage Calculations for Basins A, B, and C o-f Ridgemont Estates North 6th Addition III. Attachments,: , ► Soils Map and Tables Street and Drainage Plans. 0 ,N. M~ WAS EC~'1111rED ®CT 13 6% SkKANE COUNTY ENGINEER I %I -d P-168425 Stormwater Drainage Report; Ridgemont Estates North 6th Addition SUMMARY: The development is divided into three (3) basins; A, B, and C. See Drainage Map for Ridgemont Estates North 6th Addition. Each basin is composed of two subareas; 1) grass lawns, and 2) impervious roofs, driveways, and asphalt paved streets. Stormwater flows overland across roofs, grass lawns, and driveways and into grass drainage ponds. Storrnwater from asphalt streets flows along the curb gutters and into the grass drainage ponds through curb openings located at low points in the curb profile. The present drainage basin boundary for Basin A is shown on the drainage [nap. This basin area will change: as adjacent unplatted portions of Ridgernont estates North are platted. The area of Basin A will become smaller in the future but impervious subarea will increase. The detention and discharge facilities will be designed for the present runoff condition rather than the future condition. The drainage facilities will be constructed outside: this plat, and modifications to the pond can be made later as adjacent property is developed. The drainage basin boundary for Basin C will change slightly as adjacent portions of Ridgernont Estates North are, platted. The basin area will remain about the saine size, but, the impervious subarea will increase. Calculations for stormwater runoff were made for a present basin condition and a future condition. The future runoff condition for Basin C will require more drywells and storage than the present runoff condition. Therefore, the drainage detention and discharge Facilities along Sonara Street will be designed for the fu Lure runoff condition, since modifications to the pond would be undesirable in the future. The grass percolation areas (drainage ponds) were calculated to hold the first 1]2" of rainfall runoff over the asphalt street areas. f Figure 2, page 6-3, of the "Guidelines for Stormwater Management", by Spokane County Engineers,,was used for rainfall intensity and duration occurring at a 10-,year storm frequency. The Rational, and Bowstring Methods were used to calculate the peak stormwater runoff for each basin, and the type and number" of drywells needed for each basin based on the storage capacity of the pond. ItiG~mDN~ ~s -TNTS 5 VA ogi { (0-111 m)Dk r IvrA No - MI 16 BRA IN ACS C A 1. Gu L AT I r4 S 13 t, 19q- ~W M - - 6 A's I N - - oh-side: ~a.~e,lv~~~ - z a v ~__--x.1.9 4 - E _ T o-t-A 1.:~ m KIV 4_ b'T - ._ImpeF-V iDU-3_:~;_.-.~~.i ►-00$-.Fl-z ---A_1,a9 __ACF.C ('IVGtiMON-T ES-TA,'Cr--5 NkO?-I t CTH PDU~T~~N No . k1-1k6 DRAIN/,GE GA1.CUk-AlIoN5 9130194 KwM BASIN oh-S%ke: Aev2.1CQe'a _ ._-k'0-_.v~ear- ~~tc~•hn. c~-f=si~e:t-uhdev~.lo~e~__._..... STORAGE REQUIRES . A~ "ZoB" STORAGE--z C22~0,2~o.FT?)(_ ~Z ~N Z. 9.~.`t3 . F_T \ 1 IN• OU'C LOW HYDRoGRAPH. Z ADO ~T,J -i- Z. DougLE EARREL-.DRYwctrc.~ ~~TlrnA'Co[L (2 cFs o~Z~ S"foRA6E PRov IVED i 55 I .POND BOTTOM ,N I -7 o' POND-2 Version: 5.15 SIN: 1295160123 OUTFLOW HYDROGRAPH ESTIMATOR Inflow Hydrograph: REN6TH HYD Qpeak = 4.0 cfs Estimated Outflow: ESTIMATE.EST Qpeak = 2.0 cfs Approximate Storage Volume (computed from t= 11.90 to 12.20 hrs) 900 cubic-ft POND-2 Version: 5.15 SIN: 1295160123 Plotted: 10-03-1994 11.3 11.4 - 11.5 - 11.6 - 11.7 - 11.8 - 11.9 - 12.0 - 12.1 12.2 - 12.3 - 12.4 - 12.5 - 12.6 - 12.7 - 12.8 - 12.'9 - 13.0 - 13.1 -I 13.2 - 13.3 - 13.4 - Flaw ( cfs ) 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 * * * x x * x x x x x * * * * * * * * * * * * * * * * * * TIME (hrs) * File: HEN6TH HYD Qmax = 4.0 cfs x File: ESTITE.ES-T Qmax = 2.0 cfs * Quick TR-55 Version: 5.45 SIN: 1315460151 Page 1 Return Frequency: 10 year TR-55 TABULAR HYDROGRAPH METHOD Type II. Distribution (24 hr. Duration Storm) Executed: Watershed file: REN6TH MOP Hydrograph file: HYD Ridgemont Estates North 6th Addition Input Parameters Subarea AREA CN Description (acres) Basin A 11.94 71.0 * Travel time from subarea outfal I Subarea where user specified Used to Compute Hydrograph Tc * Tt Precip. (hrs) (hrs) (in) I 0.10 0.00 2.00 I to composite watershed ou interpolation between Ia/p Runoff Ia/p (in) input/used 0.27 1.41 .41 -fall point. tables. Total area = 11.94 acres or 0.01866 sq.mi Peak discharge = 4 cfs Computer Modifications of Input Parameters Input Values Rounded Values Ia/p Subarea Tc * Tt Tc * Tt Interpolated Ia/p Description (hr) (hr) (hr) (hr) (Yes/No) Messages 3asin A 0.10 0.00 Yes * Travel time from subarea outfall to composite watershed outfall point. t* Tc & Tt are available in the hydrograph tables. Quick TR-55 Version: 5.45 SIN: 1315460151 Pa e 2 Return Frequency: 10 years TR-55 TABULAR HYDROGRAPH METHOD Type TT. Distribution (24 hr. Duration Storm) Executed: Watershed file: REN6TH MOP Hydrograph file: HYD Ridgemont Estates North 6th Addition Summary of Subarea Times to Peak <<<< Subarea Basin A Composite Watershed Peak Discharge at Composite Outfall (cfs) 4 4 Time to Peak at Composite Outfall (hrs) 12.1 1.2.1 Quick TR-55 Version: 5..45 SIN: 1315460151 Page 3 Return Frequency: 10 years TR-55 TABULAR HYDROGRAPH METHOD Type II. Distribution (24 hr. Duration Storm) Executed: Watershed file: REN6TH MOP Hydrograph file: HYD Ridgemont Estates North 6th Addition Composite Hydrograph Summary (cfs) Subarea 11.0 11.3 11.6 11.9 12.0 12.1 12.2 12.3 12.4 Description hr hr hr hr hr hr hr hr hr Basin A 0 0 0 - 0 1 4 2 1 1 Total (cfs) 0 0 0 0 1 4 2 1 1 Subarea 12.5 12.6 12.7 12.8 13.0 13.2 13.4 13.6 13.8 Description hr hr hr hr hr hr hr hr hr Basin A 1 1 1 - 1 - 0 0 0 - 0 0 Total ( cfs ) 1 - 1 - 1 1 0 0 - 0 0 0 Subarea 14.0 14.3 14.6 15.0 15.5 16.0 16.5 17.0 17.5 Description hr hr hr hr hr hr hr hr hr Basin A - 0 - 0 0 0 0 0 0 0 0 Total (cfs) - - 0 0 0 0 0 0 0 0 0 Subarea 18.0 19.0 20.0 22.0 26.0 Description hr hr hr hr hr Basin A 0 0 0 0 0 Total (cfs) 0 0 0 0 0 Quick TR-55 Version: 5.45 SIN: 1315460151 Pa e 4 Return Frequency: l0 years TR-55 TABULAR HYDRDGRAPH METHOD Type II. Distribution (24 hr. Duration Storm) Executed: Watershed file: REN6TH MDp Hydrograph file: HYD Ridgemont Estates North 6th Addition Time Flow Time Flow (hrs) (cfs) (hrs) (ofs) 1.❑ 1 0 14.8 11.1 0 14.9 0 11.2 0 15.0 0 11.3 0 15.1 0 11.4 0 15.2 0 11.5 0 15.3 0 11.6 0 15.4 0 11.7 0 15.5 0 11.8 0 15.6 0 11.9 0 15.7 0 12.0 1 15.8 0 12.1 4 15.9 0 12.2 2 16.0 0 12.3 1 16.1 0 12.4 1 16.2 0 12.5 1 16.3 0 12.6 1 16.4 0 12.7 1 16.5 0 12.8 1 16.6 0 12.9 0 16.7 0 13.0 0 16.8 0 13.1 0 16.9 0 13.2 0 17.0 0 13.3 0 17.1 0 13.4 0 17.2 0 13.5 0 17.3 0 13.6 0 17.4 0 13.7 0 17.5 0 13.8 0 17.6 0 13.9 0 17.7 0 14.0 0 17.8 0 14.1 0 17.9 0 14.2 0 18.0 0 14.3 0 18.1 0 14.4 ❑ 18.2 0 14.5 0 18.3 0 14.5 0 18.4 0 14.7 0 18.5 0 Quick TR-55 Version: 5.45 SIN: 1315460151 Page 5 Return Frequency: (Tr years TR-55 TABULAR HYDROGRAPH METHOD Type II. Distribution (24 hr. Duration Storm) Executed: Watershed file. --a REN6TH MOP Hydrograph file: --a HYD Ridgemont Estates North 6th Addition Time Flow (hrs) (cfs) 18.6 0 18.7 0 18.8 0 18.9 0 19.0 0 19.1 0 19.2 0 19.3 0 19.4 0 19.5 0 19.6 0 19.7 0 19.8 0 19.9 0 20.0 0 20.1 0 20.2 0 20.3 0 20.4 0 20.5 0 20.6 0 20.7 0 20.8 0 20.9 0 21.0 0 21.1 0 21.2 0 21.3 0 21.4 0 21.5 0 21.6 0 21.7 0 21.8 0 21.9 0 22.0 0 22.1 0 22.2 0 22.3 0 Time Flow (hrs) (cfs) 22.4 0 22.5 0 22.6 0 22.7 0 22.8 0 22.9 0 23.0 0 23.1 0 23.2 0 23.3 0 23.4 0 23.5 0 23.6 0 23.7 0 23.8 0 23.9 0 24.0 0 24.1 0 24.2 0 24.3 0 24.4 0 24.5 0 24.6 0 24.7 0 24.8 0 24.9 0 25.0 0 25.1 0 25.2 0 25.3 0 25.4 0 25.5 0 25.6 0 25.7 0 25.8 0 25.9 0 Quick TR-55 Ver.5.45 5/N:1315460151 Executed: 11:49.34 10-03-1994 RENGTH.TCT Ridgemont Estates North 6th Addition Tc COMPUTATIONS FOR: Basin A SHEET FLOW (Applicable to Tc only) Segment ID Surface description Manning's roughness coeff., n 0.0000 Flaw length, L (total ¢ or = 300) ft 0.0 Two-yr 24-hr rainfall, P2 in 0.000 Land slope, s ft/ft 0.0000 0.8 .007 * (n*L) T = hrs 0.00 = 0.00 0.5 0.4 P2 * s SHALLOW CONCENTRATED FLOW Segment ID grass Surface (payed or unpaved)? Unpaved Flow length, L ft 800.0 Watercourse slope, s ft/ft 0.0190 0.5 Avg.V = Csf * (S) ft/s 2.2240 where: Unpaved Csf = 16.1345 Paved Csf = 20.3282 T = L / (3600*V) hrs 0.10 = 0.10 CHANNEL FLOW Segment ID Cross Sectional Flaw Area, a sq.ft 0.00 Wetted perimeter, Pw ft 0.00 Hydraulic radius, r = a/Pw ft 0.000 Channel slope, s ft/ft 0.0000 Manning's roughness coeff., n 0.0000 2/3 1/2 1.49 * r * s V = ft/s 0.0000 n Flaw length, L ft 0 T = L / (3600*V) hrs 0.00 = 0.00 .•TOTAL •TIME .(hrs)... ...t].10.. Quick TR-55 Ver.5.45 S/N:1315460151 Executed: 11:22.08 10-03-1994 Ridgemcnt Estates North 6th Addition RUNOFF CURVE NUMBER DATA Composite Area; Bsain A AREA CAC SURFACE DESCRIPTION (acres) Pvt./roofs/drives 0.85 98 grass 11.09 69 COMPOSITE AREA 11.94 71.1 ( 71 } J 1r~ I j i i i Y ~tD6eM0Wr ~SIA"f65- BASIN DESIGNATION A 44i-r,4 DF~Fst-rf_ PROJECT No F_-j4 GTH ADD1TIDN CALL k . Vj . M C-M u L k t rA DATE 110 13 19 4- CHECK DATE SOIL GROUP AREA 16.9+- (Acres) SLOPE % CURVE NUMBER: PRESENT CONDITION FUTURE CONDITION LAND USE % CN PRODUCT ~'AvT,lRvvFS I]Fz►v 5 __-7~\2-i 113 6.9 J3 WEIGHTED CN: "7 1.0-1 i RUNOFF DEPTH: P2 in. Q2 ' in. P1 -L , o in. QIO in. P5 in. Q5 in. P1O in. QlOCL. in. PEAK DISCHARGE: HYDRAULIC LENGTH o a+ ft. EQUIV. AREA Acres EQUIV. : 'X SLOPE y ADJ. EQUIV. PEAK CHART PEAK DISCHARGE FACTOR DISCHARGE FLAT (0-2%) cfs/in: MODERATE (3%-7%) cfs/in. X - cfs/in. STEEP (>8%) cfs/in. ADJ. EQUIV. PEAK DISCHARGE X ACTUAL AREA ADJ. PEAK DISCHARGE EQUIV. RE cfs/in. X Acres = cfs/in. Acres ADJ. PEAK DISCHARGE (cfs/iri.) X Q (in.) = DESIGN DISCHARGE cfs/in. X Qz in. - D cfs. Q1 in. DIO cfs. Q50_ in. D5 cfs. ,-,in. QlOo_ _ Dion cfs . FIGURE ]O 6-]5 Table 5 --Runoff curve numbers for selected agricultural, suburban, and urban land use. (Antecedent moisture condition II, and I. = 0.25) HYDROLOGIC SOIL GROUP LARD UBH DYSCRTP7I011 A C D Cultivated laad11i without conservation treatment 72 81 88 91 with conservation treatment 62 71 76 81 Pasture or range land. poor condition 68 79 86 89 good condition 39 61 74 8o liaadox: good condition 30 ~8 T1 78 Wood or Forest land: thin stead. poor cover, no mulch 45 66 , TT 83 good cover-21 25 55 TO T7 Open Spaces, lawns, par" . golf courses, ccmateriee, ate. good caadittojl; grass cover on, 75% or more of the area 39 61 14 80 fair condition: grass cover an 50% to 75% of the area 49 69 79 84 Commercial arts business areas (85% impervious) 89 92 94 95 Induatrtal districts (723 impervious) - 81 88 91 93 Residentia;:21 Average lot site Average % Imparviouall 1/8 acre or lees 65 77 85 90 92 114 acre 38 61 75 83 8T 113 &era 30 57 72 81 86 112 afire 25 54 To 80 85 1 mare 20 51 68 79 8L Paved parking lots, roofs, driveways. etc.-I1 98 98 98 98 Streets and roads: paved with curbs and atorm @overall 98 98 98 98 gravel 76 85 89 91 dirt T2 82 37 89 =1 Por a more detailed deacrlption of agricultural land use curve numbers refer to Rational Engineering Handbook, Section 4, Hydrology, Chapter 9, Aug. 1972. =0 Good cover is protected from grazing and litter end brush cover soil. f1 Curve numbers are computed assuming the runoff from the house and driveway to directed towards the street with a minimum of roof water directed to lawns vhare addltia+ul infiltration could occur. =1 The remaining pervious arena (lawn) ore considered to be in good Faature condition for theoe curve numbers. is In some waTDer climates of the country a curve number of 95 may be used. 6-8 TABLE 5 • .I r F o+ ,ra smQ R7 as-rrlTGs No F- 1 R 6-rti f aS/ Y~ 1 ~~Y~r NSA M,116 ~ 'D~AINA~~ C.AI~ Cu L A"f tivN ~ ~ Jig Acrd ~ ' P'~~~11Q'13:? 2.0 F-k7>< SMOWV 5S7pTFs N09TH 6TH ADDLTloN X2:7 vG tC- NN M B"IN $7D,F-A (~-E. -5-Q l2 1~. /AFT. 1B ow N 6 ~z cfs ow) 5'Cot~AG~ '~Ro!~_4C~Ep'. F 711~37 .1-7 - - Erl 60, 60 'Z A. •11) RATIONAL FORMULA HYDROLOGY DK i L m 9/20/Vl DE53 CsNER m K W MCMULKIN F'hDJECT NAME = R.E. NORTH 6TH ADD. DESCRIPTION STORNWATER DRAINAGE SUBAREA 1 = 1.07 ACRES SUBAREA 2 = 2.11 r9r._RES TorAL AREA = 1,19 ACRES OVERLAND FLOW VALUES ct a .15 L- - G i - 01 ETANNEL FLOW VALUES L_ - 505 21 = . 172 Z2 26 N - .016 B [_1 S .013 TD = . 655 POD Pi Fl=D VALUES DUR - 5. oo 110 7. In 1"4 4 07- =Q m 07, BASIN "B" C:M3°ii A L RUNOFF COE FF 1 f : L ENT „ .9 SUBAREA 2 RUNOFF COG FF 1 C 1 ENT = .15 C.:OM1=`OO T TE RUNOFF COEFFICIENT » 4022504%5b6 I: 0Wl,RTR l.IqG CAL.CL}I-A r I ONS nt`ETF = 9f 2n f";-1 DE57 C,NER ° I' W MCMUi. K I N DI AIS I N "13" PROJECT NAME F,. E. 11ORTH 6TH ADD. lj SCRIPT1ON = STORMWOTE'R DRAINAGE t -t. 11.1 terisIty Ud 'F-v. V I ri t+out stol-affiF (x, L n . } =i i:.,) 0 11. /hru 4- . s. } LC I[ 4' 1.. } ~(.:Lk. ft. ] CCU. f t-. } 5.(-) b[7sl 71. 1G 4. 07 16 ';6 600 1£)'G 10.0 600 2. 24 2. 0-7 2012 1200 81.^ 15 . C) 'W-10 1.77 ~ . 26 22 69 } ~C 1[ I 46P 110. (1 1200 l 45 1.81) 2416 ^=4[ 1r~ 16 2-5. t1 1500 1 .21 1. 55 '400 OOC) -520 7c). 0 101-)C) 1.01 1 . 7 R 275 1 600 -1069 . 1 2100 .91 1.16 256A ■1200 -1 67 4C7. 0 .132 l . 4000 - 17v 45. t 3 27,, Wj . 74 .95 265, e a 4[=;t7 : ; l 5c). [f YcJ00 .68 .117 _ 2699 6000 --7,701 :e . -04) . 634 . 8,2 2726 66CI[nl 13(13 14 ear i . 0 i6 0 .61 .70 2381.2 720C) "Y ~ 1 1 65.0 .60 . 76 5047 7c900 -475 70-0 4200 .58 .74 7-,19~ •0400 --5207 GCS 4L, .5--, .613 . s'If 112600 --6276 35.0 5e1CIO .52 .66 -4211 10-2100 --6772 90. 0 5400 . so . 611 `15` 0 10200 2Q0 '?i.0 5 '[)C] .49 '6 ,R 1 14CIC) -7762 1 CDC. C} 60100) .40 . 6j, " 71413 12000 rv-8252 THE' MAXI NUM GTQRRGG IS 10 75. 66162 C:LI. FT. The tirno of concentration i 5 mi.nu,trW--. TEN YEAR STORM C A C