27882 DRAINAGE REVIEW FILES
Y
f ~
I
i
S P O K A N E C O U N T Y
DNISION OF ENGINEERING AND ROADS A DNISION OF THE PUBLIC WORKS DEPARTMENT
I William A. Johns, P.E., County Engineer
August 25, 1999
Doug Busko, P.E.
David Evans & Associates
110 West Cataldo
Spokane, WA 99201
adley Heights
l
~ SUBJECT: WuSbo r
mittal
Gentlemen:
We have conducted a cursory review of your August 9, 1999 submittal of the road and
drainage plans for this project. We.regret to inform you that the submittal is not in
accordance with the Spokane County Standards for Road and Sewer Consiruction
(SCRS), 1995. We are therefore unable to accept your submittal for construction.
We are enclosing a list of the items noted in our cursory review. Please ca11 Ed Parry
((509) 477-3600) if you have any questions.
Sincerely, William A. Johns, P.E.
Spokane County Engineer
Ed Paivf, P.E.
Plan Review Engineer
Encl
cc: File
1026 W. Broadway Ave. o Spokane, WA 99260-0170 •(509) 477-3600 FAX: (509) 3243478 TDD: (509) 3243166
. i
P1848 - Bradley Heights
Items Noted from 15` Submittal
August 25, 1999
1. Developer's signature & date should be provided on each page of the road & drainage
plans
2. The Engineer's Certification Statement is needed on the cover page of the Drainage
Calculations
3. 208 Lot Plans: (returned under separate cover)
• Section details need to be provided with the respective Lot Plans; Section details
should be secured (but not stapled) to the Lot Plans.
4. Road Plans need to indicate the 5' future setaside strip
5. Curb radius at the NW corner of Mission & Center may need to be a 30' radius -
pending coordination with County Traffic Engineer.
~
RECEIVED
Submittal Checklist AUG 0 9 1999
for Road & Drainage Projects in Spokane County - Platsg tIrt`6ENGINEER
This Submittal Checklist is to be completed and signed by the Sponsor's Engineer, and included tivith euch plun
submittal irrtv Ihe Spokane County Engineers Office. If this form is not fully completed and sigried, donot submit
plarrs and calculations to Spokane County for review and acceptance. Incomplete submittals will be returned
and tivill cause unnecessary delays for your client.
Project Name: ~~Ab 1._6 y I`hS t
Spokane County Project No. ~-A8¢8 Date:
Proj ect Engineer: AS-S o Cv-• Phone: -r-R-7- ? - ABGo c!> ~
Project Sponsor: Ji e-I/~'1ie►s,~A'R Phone: 879 -N?4-9%.5-
A. Preliminary Process
Prior to Submittal of Road and Drainage Plans, the following events are to have already occurred:
(By checking each iten: off shown below, you are stating that yoat have verifred these events/items have been completed)
~
Adoption of a Hearing Examiner's Report for this long plat, or a Planning Report for this short plat.
At least one Pre-Design Meeting has been held with County staff at the Engineers Office.
90" An "Agreement to Pay Fees" has been signed by the project sponsor, and submitted to the County
Engineers Office.
p A Channelization Plan (e.g. signing and striping plan) of public roadway improvements, has been
N/A coordinated and discussed with the County Engineers Office.
B. Road and Drainage Plan Submittal
The items listed below are to be provided as a minimum with a road and drainage plan submittal. Additional
information may be required to demonstrate that the plans meet all applicable standards.
(By checking "yes " for euch item shown below, you are verifying thut these items have beerr completed and are included in
this saibmittal. For uny box checked "n/a", a written jzcstification of any omis.sions at the end of this section is reqtrired.)
~ Item Description
yes Road and drainage plans, ttwo print sets. (Certification statement on cover of pians)
Vyes Each Plan Sheet of record is signed and dated by the project sponsor.
Vyes The road and drainage design meets the requirements of State law, WAC 196-27 regarding
"conformity with accepted standards"; that is, the design reflects the "state of the practice"
~ for the proposed concept.
Vyes The plans, Drainage Report, basin map(s), and any other calculations are stamped, signed
and dated by an engineer licensed in the State of Washington. -
EKyes 0 n/a Drainage Report, two sets. To include: basin map(s), time of concentration routes in basin
map, and Certification statement on cover of report and basin map.
r
0 yes l~Yn/a Geotechnical Report, one set. (Include all soil test pit/boring logs.)
0 y_es GYn/a Structural Pavement Calculations, one set p✓,4-4T, .5e=~NS ~~ow.d~ q~1~'~
fd'yes 0 n/a Cross-slope grade calculations for road widening projects.
~
0 yes 0'n/a Maintenance Manual and Sinking Fund calculations for drainage facilities located outside
~
J
~ of County road right-of-way.
0 yes iY n/a Written eYplanation of who/what entity will be responsible for maintaining drainage
facilities which are located outside of public road right-of-way, and that the plan is
acceptable to the County Engineers Office.
0 yes V,n/a Channelization Plan, or signing and striping information provided in the road plans. To be
` included in road and drainage plan set.
Q'yes 0 n/a I have read the Hearing EYaminer's Report (long plat), or Planning Dept. Findings and
/ Conditions (short plat), for this project. The design meets the conditions in the report.
~a Copy of Approved Design Deviations.
i'yes 0 n
0 y,es Vn/a Fire District Approval, for private roads.
0'yes 0 n/a Lot Plans. Required for any lots with drainage easements and which front a public road, or
for lots which receive and treat runoff from a public right-of-way.
~
0 yes Rn/a Any applicable State and Federal permits have been obtained. (i.e. HPA, JARPA, etc.). For
Permits with conditions, a copy of the permit and conditions are included in the plan
subm ittal.
l~yes 0 n/a Inspection Agreement between the sponsor and its engineer.
0 yes 9`00'n/a For off-site easements to be granted to Spokane County, the following items shall be
included: legal description, exhibit, and proof of ownership.
0 yes LYn/a Erosion Control Plan, required for "Major Land-Disturbing Activity." To be included in the
road and drainage plan set.
Explanation for any items listed above which are not included in this submittal:
(Note: an insufficient justification of why an item was not included in the submitted, or incomplete documents, may result
in the submittal being returned without review or without acceptance. Provide attachments if necessary.)
By signing below, the engineer is stating that the information provided in the submittal is complete, that the
information provided in the Subrnittal Checklist is accurate, and the plans and calculations are in accordance
with the Spokane County Standards for Road cPc Seiver Construction, and the Guidelines for Stormwater
Management, except where an approved Design Deviation allows otherwise.
Engineer's Signature: Date: 7- l~ gy
Engineer's Name:
(please pr'int) i
If there are any questions about this form or appropriate procedures, please call Developinent Services,
Spokarre County Public Works, at (509) 456-3600.
For Spokane County Use Only
Submittal No: County Plan Reviewer: Nq
~f Accepted in for Review ef-EeirstntetiIIn
~ Returned to the engineer without acceptance, See attached letter of explanation.
Processing Date: Zr7 /~J ~
Submittal Checklist 2
Spokane County Public Works; Apri129, 1998
R C IV~~
-
` REQUEST FOR DESIGN DEVIATIUN ZA 6 6~1ggg
s~o.oo ~
DEA-SPK
DATE June 28, 1999
ROAD NAME Edgerton Court ;7-f CRP/RID ~
: . ..r . ;
NAME OF PLAT Bradley Heights ~ ~4 1999 Ptat # P-1848
ADDRESS OF BLDG
NAME OF BLDG PROJECT •
BLDG #139 Section 7 Township 25 Range 94
FEDERAL/STATE PROJECT # PROJECT LIMITS Nora to CDS
' EXISTING CONDITIONS PROPOSED IMPR4VEMENTS
ROAD W1DTH 90' 40'
RG~►^ SU:ZF.°.CE ACP ACP
AVG. DAILY TRAFFtC
Current Tcaffic Count Design Year Traffic Count
PROJECT DESCRIPTION This plat will extend Edgerton to the south with a Spokane County
standard full cul de sac.
PROPOSED DESIGN DEVIATION Place 5' cement concrete sidewalk directly behind curb,
instead of 7' behind curb. .
JUSTIF1CATlON The layout .of the lots in the cul de sac makes contiguous sidewalk a bet-
ter choice in this case. The frontages on the lots are narrow - setting the sidewalk
away from the curb would serve to exacerbate the feeling of confinement in the cul de
sac. No sidewalk exists on Edgerton Court to the north, therefore, the new sidewalk
does not have to match a specified location. Drainage from the cul de sac will be di?--
ected under the sidewalk to swales located behind the sidewalk.
- RECE:--VE
. AU6 UC~'~' -
SUBM(TTED BY: David Evans and Associates, Inc. DATE June 28, 1999
ADDRESS West 110 Cataldo, Spokane, Washington
ZIP CODE 99201 PHONE T (509) 327-8697
**"ADMINISTRATIVE VARIANCE FEE OF $30.00 PAID TO SFOKANE COUNTY****
1026 WEST BROADWAY, SPOKANE, WASHINGTON 99260- 170 PHONE (509) 456-3600 FAX (509) 324-3478
41 rtC~ -REQUEST WILL NOT E Vl 1VITHOUT FUNDS-
Y
CRSH/CHECK40 # ol RECEIVED BY ~l DATE -4~'~2
K/FORMS/DESOEV.frm
• - ' • ..4
. ~
. . ' , DESIGN DEVIATION .
:
STAFF RECOMMENDATIONS
Approved Approved w/conditions Not Approv4 ( ~ ( ) ( ) c~'
Pro,}ect Manager Date
~GO r+~ wu.-~v~ ~ P
. .
Appr ved Approved w/conditions Not Approved
~ ) t ) -2
'
Project Managemek En~ineering Date
Approved Approved w/conditions Not Approved
Operations Manager . Dace
SPOKANE COUNTY ENGINEER'S DETERMINATION:
Ap roved Approved w/conditions Not Approved
.
) O t) ~
Spkane County Engineer Date
KIFORMS/OESOEV.frm
r ~ RI __iUEST FOR DESIGN DEVl`~.'ION
S30.00 ~ Z
. ~
DATE June 28, 1999
ROAD NAME Mission Avenue CRP/RID #
NAME OF PLAT Bradley Heights Plat # P-1898
ADDRESS OF BLDG
NAME OF BLDG PROJECT
BLDG #139 Section 7 Township 25 R,ange 4 4
FEDERAUSTATE PROJECT # PROJECT LIMI"I'S . Park to Center
EXISTING CONDITIONS PROPOSED IMPROVEMENTS
ROAD WIDTH 12' 20'
ROAD SURFACE ACP ACP
A VG. DAILY TRAFFIC 2000 2000
Current 7'raffic Count Design Year Traffic Count
PROJECT DESCRIPTION Currently, Mission Avenue has a 24' wide paved surface with no
curb or sidewalk. In conjunction with the plat, the road will be brought to Collector
Arterial standard, with 18.5' of ACP, curb and gutter, sidewalk, and drainage swales
on the north half of the road.
PROPOSED DESIGN DEVIATION Construct 63' of Type B curb and gutter at a longitudinal
slope of 0.44$ to 0.47%, below the County standard of 0.5$.
JUSTIFICATION Spokane County repaved this road in 1997 following construction of the
West Vall.ey sewer. As shoc-m on the attached grade sheet, cross-slopes are consist-
ent1X around 2$, but the longitudinal grade on the edge of the pavement varies from
0.03% to 1.62%. The 0.44$ to 0.97$ curb grades correspond to the areas where the edge
of pavement is currently 0.03$ to 0.32$. Proposed cross-slopes on the substandard
curb range from 2.08$ to 5.00$; the steeper cross-slope will aid in getti-ng runoff
to the gutter line quicker. Two Type 1 curb inlets will be constructed in this
section to prevent ponding in the gutter and roadway.
SUBMITTED BY: David Evans and Associates, Inc. DATE June 28, 1999
ADDRESS West 110 Cataldo, Spokane, Washington
ZiP CODE 99201 PHONE # (509) 327-8697
;•'~*ADMMISTRATIVE VARIANCE FEE OF 0.00 PAID TO POKANE COUNTY*•t*
,
1026 WEST BROADWAY, SPOKANE, WASHINGTON 60-0170 PH E(509) 456-3600 FAX (509) 324-3478
„rREQUEST WILL NOT BE R #I'E D UT FUNDS-
~ -
CASH/CHECK # 0 RECEIVED BY DA7'E ~ ~
i
K/FORMS/DESDEV.frm
DESIGN DEVIATION
STAFF RECOMMENDATIONS
~ ~cpr►r1+~'~ ~ ~f~'Ot1,i~. .
Approvsd Approved w/conditions Not Approved
( ~ ( ) ( •
~
Project Manager Date
, . ~
Ap ved Approved w/conditions Not Approved
,
( ~ ( ) ( ) ~/~l~ ~
Projict Management Eng(neering "Date
Approved Approved wlconditions Not Approved
, i.~ 7 -
v v
Operati s M ager Date
SPOKANE COUNTY ENGINEER'S DETERMINAT[ON:
Appr ved Approved w/conditions Not Approved
Spokane Counry Enger C Date
K/FORMS/DESDEV.hm
-Spokane County'_-crgineers rroject: tiramey Heignts bundivisian '
W.1026 Braadway Ave 477-3600 Ja6 Na.: MAHAAAA4 coeywQ,15-
Spakane, WA 99260 Disc.No.:
File Name: Missian, MAHAQQG4-
XYPICAL SECTION DATA 9P13-vx5_ 25-Jun-99
Roadway half width ENTER--> 20 09;21 AM
Raad Name ENTER--> Mission Avenue QUVBO
Left or Right EN7ER--> Left
Curb Type IN7EGRAL CURB & GIJTTER
Station Interval ENTER•-> 25
Curb EL. Curb EL. Edge Pave.
CENTER °l0 5LC1PE EDGE aIST. % SLOPE EaGE DIST FRQM (-4.5°/0 (-2°lo to Gutter
LINE CENT'ER- PAVEMENT ' CfL TO CfL TO PAVEMENT EDGE PVMT, from E!P + FROM EfP + SELECT- besign Top Curb
$TATION F-LEVATION LINE ELEVATION E!P EDGE PAVE °lo SLOPE 10 CURB FRCE CURB HGT) CURB HGT) Ed ELEV °la GRADE % Grade
15fi,58 55.60 55.32 12.00 -7.33 0.008_00 55.41 55.58 55.42 -4.38
194.30 55.92 0.85 55,69 12.00 -1,92 0.98 8.00 55.78 55.95 55.79 -4.38 0.98
218,54 56.10 0_74 55,84 12.00 -7.17 0.62 8,00 55.93 56,10 56.48 -2.23 1.24
25046 56.46 1.19 56,24 12.00 -2.00 1.26 8.00 56.33 56.50 56.47 -2.38 1.22
282.54 56,97 1.52 56.69 1Z00 -2 33 1.40 8.00 56.78 56.95 56.86 -131 9.21
313.38 57.44 1.52 57.19 12.00 -2 08 1.62 8.04 51.28 57.45 57.31 -4Z8 1.46
344.77 57.7E 1.00 67.54 92.00 -2.40 1.12 8.00 57.83 57.80 57.74 -146 1.24
315,59 58,00 631 57.79 12.00 -1.75 0.81 8_00 57.88 58.05 57.88 -4,54 0.58
440.37 58.38 0.59 58,19 12,66 -1.67 0.60 _ 8.00 58.27 58.44 5823 -5.15 0.54
471.86 58.51 4. 58.28 12.60 -1.A2 8.00 58.37 58.54 5837 -0.54
503,69 58,52 58.27 12.00 AIR 5.00 58.36 58.53 58,52 -2.08
5341p v8.5¢ 5$,32 12,G0 8.00 58.41 58.58 58.38. -5A0
585.35 5$.71 4. 58.47 12.ab -0 49 8.00 58.55 5813 58.64 -3.92 4,72
596.49 58.88 0.55 68.E6 12.00 -1.92 0.58 8.00 58.74 58.91 58.82 -3.31 0,71
627.72 59,07 6.61 58.85 12.GD -1.83 0.64 8.00 58.94 59.11 59.02 -3.31 0.64
658.21 59.22 0.49 59,00 12,00 -1.83 0.49 8.00 59.09 59.26 59.20 -2.85 0.59
688.86 59.39 0.55 59.99 12.00 -1.67 062 &00 59.28 59.45 59.44 -2.08 0.78
119.01 59.58 0.63 59.29 12.00 -2.42 0,33 B.00 59.38 59.55 69.59 -1.31 0.50
725.14 59,61 0.49 .°'.59.23 1&50 -2.45 -0.98 1.50 59.82 59.82 59.82 0.49
ca
'Ph* -o
~
~ ~
~ ~
~ ~ ~ ~
~ ~
~ ~ ~
lrn
m
:)D
DRAINAGE REPORT
Bradley Heights Subdiv.ision
Spokane County, Washington
Prepared for:
Jim Mahar Homes, lnc. .
y
8121 E. Maringo
Spokane, Washington 99213 ~
RECEtVED
AUG 0 9 1999
SPOKANE COUNTY ENGINEER
DEA ProJ'ect No.MAHA0005
AS .
of
A
. ~ ~
~
July 14, 1999 3075
~I~NAL
. EXPIRES 101091
• ding Professio •
O • Quality DAVID EVANS AND ASSOCIATES, wvg~
~ -
'
TABLF OF CONTENTS .
1. PROJEC1" DESCRIPTION I
A. Introductian . . . . . . . . . . . ..1
' II. H1fDROLOGY 1
A. P;re-Development Basin 1.
B. PastyD eveioprnent Sasin 2
I{l• V ONCLUSI O Ns ■..............................i...............................r...i...i.....iiii..iai.i.ii.i.i...iA..i.i.ii.114..J.■ ~
~~~~~~~~~S
Appendix A Site Location and Soils Infarmation
~ ApPendix B Hydralagic and Hydraulic Caleu.lations
Appendix G' Si~e Photos
Appendix D Past-Development Basin Map
~
~ -
~ -
~ - -
drainage ReporE for Bradley Heights Subdivision
lU9,4HAOOTlDRAIN REPT'E 3_I)OC ~ 07M4199
~cn
DAVID EVANS AND ASSOCIATES,
T R A N S M I T T A L Wat Ijo Cataldo
To: Bill Hemmings, P. E. spokane, Wcuhington 99201
Spokane County Engineers RECEfVED
1026 W. Broadway T~~ 509327-8697
Spokane, WA 99260 AUG 09 1g~qq Fax: 509327•7345
DATE: AL19USt 4, 1999 SPpK,qNE COUNTY ENGINEER
FROM: Doug Busko, P. E. -
PROJECT: Bradley Heights Subdivision /848
,
PROJ. MAHA0005
' ITEM COPIES DATE DESCRIPTION
1 2 8/4/99 Road & Drainage Plans with Drainage Report
2 1 7/14/99 Submittal Checklist
3 1 8/4/99 Inspection Agreement 4 1 6/25/99 Grade Sheet for Mission Avenue
❑ AS YOU REQUESTED ~ FOR YOUR APPROVAL ❑ RETURN REQUESTED ❑ DOCUMENT CONTROL
❑ FOR YOUR INFORMATION ~ FOR YOUR REVIEW ❑
COMMENTS:
B 1ll,
We are submitting the completed package for Bradley Heights for review. Please call if you need anything else to
complete the review.
Thanks,
Doug Busko, P.E.
• o• . • g•
s:lengrlmah0005\trans_hemmings.doc
~cn
1
1
1. PROJECT DESCRIPTION
A. Introduction
Bradley Heights subdivision is a seventeen lot, single family development located near the intersection of
Mission Avenue and Park Road in the Spokane Valley, covering approximately four acres. Road
improvements for the plat include the widening of Mission Avenue and construction of a new cul de sac in
' the north central portion of the plat. The project is in Section 7, Township 25 North, Range 44 East, in the
Spokane County, Washington, and is located within the bounds of the Rathdrum AqLiifer Sensitive Area
(ASA).
This report examines the proposed stormwater collection, treatment, and disposal methods that will be
employed in conjunction with this development. '
'
II. HYDROLOGY
A. Pre-Development Basin
According to the 1968 Soil Survey of Spokane County, Washington, prepared by the Soil Conservation
Service, the soil on-site is Garrison gravelly loam. This soil is found on slopes of 1 to 5 percent and is
_ somewhat excessively drained. Spokane County has pre-approved the use of drywells for soils in this
' classification. Please refer to Appendix A for additional soil information.
Currently, the site is undeveloped-groundcoyer on the site consists of dense weeds and brush. The ground
slopes at approximately 1% from east to west, and it does not appear that the grade on the site has ever
been appreciably altered. Runoff currently stays oti the site and seeps into the ground following storm
events. No evidence of erosion or damaging runoff patterns is apparent.
Center Road, the plat's east boundary, has curb and gutter that discharges to a dryWell at the intersection
'
of Mission and Center. Edgerton Court, on the plat's north boundary, slopes toward Bradley Heights; a
drywell in each gutter line intercepts the flow before it enters the Bradley Heights plat. There appear to be
no other possible sources of offsite flow around the site that need to be considered in this analysis.
Drainage Report for Bradley Heights Subdivision 1
MAHA00T/DRAINREP713.DOC 07/14/99
'
~cn
i
B. Post Development Basins
' Mission Avenue is divided into six post-developed basins. One grassed percolation area is located within
each basin. Only every other percolation area, however, will be provided with a drvwell. The areas
without drywells are designed to pond to a depth of 6 inches before overflowing down the gutterline to an
adjacent pond with a drywell. Type 1 curb inlets with 2' openings will be constructed with all swales to
aid in conveying runoff off of the road surface.
One swale will be provided for each half of the new Edgerton Court cul de sac. The drainage swales will
be located within the 20' border easement that girdles the cul de sac. A Type 2 curb inlet will be
constructed for each swale, to convey runoff under the sidewalk. One Type B drywell is to be constructed
' ' n each swale.
~
The drywells for the project have been designed to dispose of runoff from not only the road areas, but also
from the lot areas. From Table l of the Guideli»es for Stormwater Munagerrrent, the "C" factor for a
density of 4.25 DU/GA (17 lots/4 acres) is 0.40. Because the precise grading plan for the lots is not
known at this time, an approximate post developed basin scheme has been developed for the interior of the
plat. Thus, a"C" factor of 0.40, along with the approximate interior basin areas, were used to perform
Bowstring calculations. Minor changes in the basin boundaries for the lots should not have a significant
impact on the drywell requirements.
The swale fore each basin was sized to treat the volume of runoff from a one-half inch storm on the
asphaltic surface within the basin. Drywells and inlets for the project were sized using a ten-year storm
intensity. The calculations for the swales and drywells are summarized in the table below.
,
SWALE - 208 VOLUME 208 VOLUME DRYWELL
' REQUIRED, C.F. PROVIDED, C.F.
A 51 52 1 Type A
B 67 70 None
C 61 94 1 Type B
D 59 59 None
E 91 92 1 Type B
F 108 108 None
G 154 186 1 Type B
H 154 186 1 Type B
Drainage Report for Bradley Heights Subdivision 2
MAHAOOT/DRAIN REP713. DOC 07/14/99
'
~cn
1
IIi. CONCLUSIONS
The proposed improvements described in dlis report and shown in the plan set will provide stormwater
control and treatment in full compliance with Spokane County's Guidelines for Stormwater Managenzent.
Drainage Report for Bradley Heights Subdivision 3
MAHAOOT/DRAI N REP713. DOC 07114/99
Appendix A
Site Location and Soils Information
~ C-fil
Outstanding „
• . . Quality DAVID EVANS AND ASSOCIATES,
CaUNTY• wASNINGTON
SPO~NE R. 44 E-
~
. (f oif15 Sheet 57)
• ~ '+.ry ~'~j'"' ~ l _ ~ t,
- kr`~9' ' 4• ` w' ~ ti~., tt~
' 1( • s N,- I ~ dJ w
r S
OWL
~
l
a
rQy
Q
i
y t f ~J~
•S
t~ l Q
S ~
5 T
~ h
ai ~C
i 9
a
Y~
yT,~~~i
O
=8
{
=t
f.
f iM
_ y
4
~ N
(
1
~r
~
T
Y
I Mite Sicate 20 000 ~
- ~
(loins sheet 73) 3h
y
. o
~
1 .
,
.
C
t
118 sou, svR«r
,occupy rolling to hilly uplands. They formed vi layered they are eacellent pl_a_,ces for hunting migr€~tory wtiterfowl. ;t
loess under coniferous forest. The annual precipita,tion is (Capability unit VIIIw-1; not ui a woodland group or °
alwut 23 inches, and the frost-free sea,son is about 125 days. ra.nge site)
Freeman soils are used for grain, peas, clover, alfalfa,
and gra,ss, and as woodland. Garfield Series
Freeman silt loam, 5 to ZO percent slopes (FaB).-This
lis the dominant soil on the silty upland north and east of The Garfield series consists of well-drRined, severely :
Rockford. Most slopes are between 8 and 15 percent; a erociecl soils that #ormed iii loess uncler grtiss aiid small
,few small areas have slones of niore than 30 gercent, and shrubs. These soils occu -)y ridgetops, knobs, tind the up- soine of less tlian 5 percent. Slo es of inore than 20 Per- per slopes on rolli to hi~ly uplands. They h~,ve a surface '
cent are slioit ~.nd ~are alon.g the eces of the drainagewa3~s.1a.3-er of silt3T clay~oam and a subsoil of silty clay tl~at is .
Represeuitative profile : reiT hard, sticlry, and plastic. The nnnual Precipittition
o to 7 inches, very dark grayisL-brown, friuble silt tonui; is 18 to 22 inclies, and the frost-free season is about 140
granular structure; neutraL dzyS.
v
7 to 17 inches, bromn, friable silt loam, grayisb brotvn at a fihese soils nre used m~,inly for ~,in, alfalfa, nnd ~r~ss.
deptli ot 12 inches ; neutral. Garfieid silty clay loam, 0 to 3percent slopes, severe- .
17 to 22 inches, grayish-brown, Srm sllt loam that breaks into ly eroded (GaC3).-This soil occupies the uarrow riclgetops
1- to 2-inch prlsms; neutral.
22 to 72 inclies, dark-brotvn, flrm silty clay loam, almost sitt alld upper slopes on loessll up11iicis ui tlie soutlie.lsterii
loam ; breaks into prisms i to 2 inches wiae, and then into pait of tlie cowiEy. AZost slo es nre between 8 niicl 20per- •
,
angular blocks Ih inch to 1 incb wide ; neutral. ceiit; a few smnll nrens have sopes of more thaai 30 perceait,
The surface soil, when moist, rnna-es from very dnrk and some nnrrow ridgetops liave slopes of less t.lizn 5 per- rn.Sish broR-n to dark brown in color. The texture of tlie cent. Represeiitative pi•ofile :
li'ubsoil tp, es from hea,vy silt loain to silty Clay loaitl. p to £ inclies, darl:-Uro«u, Ilrxu silty clay loam ; granular struc-
As much ~ 7 perr,ent of some areA,s consists of Y.arkin, ture ; neutrnl.
,Dew-yton, or severely eroded Freemau soils. S to 48 inches, dari:-brown, Srin silty clay, yello«ish-bron-n ,
Tliis is 1. moderately tivell drained soil that has avery sitty clay loa,n below a depth of 23 inches ; breaks into
Prisms
slo~rly perme~.ble subsoil and is saturfl,ted for short periods ~ 1 inch to 2 iaches mide and tl~en into angular Ulocks
to % inch thick; clay films coAt the prisms and angulur
in sprin~;. It holds about 5 to 7 inches of mater that lAnts vlocks ; neutral.
CAit LiSC. It is easy to work except R'1,I1 &tituTlLted. OOtS 4$ to 60 inches Sellowish-broR7n, firin Ueavy silt loam ; Lreaks
lFertility enetrate the lower layers mainly along ped fa,ces. The int° nrisms 1 to 2 fnches ~~=ide and then in~to angular blocl:s
is medium. 'Surface runoff is medium, and the 'A t° % Iuch tnick; neutrai.
ha.zard of erosion is moderate. Tlie tes-tui-e of the upPer subsoil is silty clay or cla3•. As '
1liore thzn 95 percent of the acreage is cultivated; the 11Tttcli as 10 percent of some a,re~.s consists of Athena, \aff,
rest is farni woodlots. ~Pheat is the chief cash crop. It Nez Perce or Palouse soils.
iis o~vn in rotation with eas and a green-manure crop This soil is ~~e11 dra.ined and slowly perme,~,ble. It holds oi• ~'inTawhea,t-fallo~v rot,a,tion. Other crops grown are peas 9 oi 10 inches of water that plants can use. It is stick-y
liid barley; clover or alfalfa for ha,y or &reen manure; and aid plastic 'wlien wet; consequently, it caai be cultiA-atecl
r~ss for seed, hay, or ps.tsture. All gr~,in a.nd grass crol~s o111S► ~~ithin a rtither n~,rrow range of moisGure content. ~
pond to nitrogen. Leg~umes respond to sulfur. {Cap~,- R4ot peiiet~raGion is very deep. The fertility is medium.
bility wut IIIe-3; ~oodlandfor oun 5; not in a range site) Surflce ruiioff is rapid, and tlie llazard of furtlier erosion
Freeman silt loam, 5 to percent slopes, severely isseveie.
eroded (FaB3).-DSore tha,n 50 percent of the surface layer ~Iore tlklii 95 I~ercent of the ~,cre~ge is culfii~-atecl; the
of this soil h1s been removed b erosion. Fertility is me- 1•est is seeded to ~.1#a~lfa or gr~,s.s. ~~Pheat is the cliief crop.
dium to lon . Surf~,ce runoff is ra,pid, and the hazlrcl of Otliei crops gro~~n are barley and dry field Peas. A11
erosion is severe. As much as 10 percent of soine ~re~s ciops respoiid to nitrogen, sulfur, and pliosphorus. (Ca-
'consists of t~neroded Freeman soils. ptibility unit No--3 ; not in a~vooclland groun or range site)
The same croPs are g?own as on Freeman silt loam, 5 to ,
20 percent slopes, but yields are lower. (Capability wiit Gal'1'iSOn Series
IVe-3; woadla.nd group 5; not in a range site) Tlie Garrison series is made up of someivhat escessively
Freeman silt loam, 20 to 30 percent slopes, severely d1lined, gravelly or stony soils that formed under grtiss
leroded (FaC3).-DSore than 50 percent of the surface 1aer
ui gllcial outwasli miaed in the upper part with ~-olcanic
of this soil ha,s been removed by erosion. Surflce runoff ~,Sli. Tliese soils are on nearly le~~el to moderately stee
s ra,pid, tind the erosion ha,zard is severe. Included in ~11•aces. The annual precipitation is 18 to 22 inclies, tincl
m~,pping ~-ere a ferv areas of I}ea.ryton soils. the frost-free se.,son is about 170 d~,ys.
The sa,me crops ~.re grown as on Freem~an silt lo1m, 5 Soils of tlie Gtirrison series ~,re used for a ~~~riety of
to 20 percent slopes, but yields are lo~ver. (Ca~pability cro s~,nd as f~,rmsteads and suburba,n lots.
Cesh t IVo--«oadland group 5; not in range site) G~arrison gravelly loam, 0 to 5 percent siopes (GgA;.-
Tliis is the dominant soil in the Spokane Valley east of
Water r Marsh tlie city of Spokane. Most slopes are between 2 and 5
percent. Representative Profile :
Fresh w-ater marsh (Fm) consists of shallow, swampy
Later onds and of fringes around lakes that ha,ve a fluctuatin o to 15 inclies, black, very friable gravelly loam ; granuiar
level. The vegetation consists of tules> reeds> ang structure ;,siigbtiy acia.
15 to 44 inches, dark-brown, friable ver9 gravelly loam ; neutral•
ruslles. These areas are of little va,lue for grazing, but 44 to 60 inches multicolored sand, gravel, and cobblestones. •
1
SPORANE COUNTY, WASHIA7GT0\ 19
,
The -urface color, when moist, ranges froin very dark the county. 3iost slopes are between 6 aud 15 percent,
b wn to black. The teature of the surface layer is grav- Representative profile :
e or very gravelly loam or silt loam. Tlie subsoil i-a,nges o to 13 inches, t,tack, very friavle siit loam ; granular structure ;
ii olor from dark brown to yellowish brown. Clay and neutraL
lune have accumulated on the bottom of the peUbles in the 13 to 62 inches, darl:-brown, firm loam tliut Ureaks into nrisms
lower subsoil. The depth to the gravel substratum ranges 1 to 2 inclies wide; sliglitty acid.
f 30 to 55 inches. A.s much a,s IO percent of some a.re.ts 62 to 72 clark-broa•u, friab1e 1oam; slightly acid.
ts of Bong or Phoebe soils or of other Garrison soils. In places the surf~,ce layer is very dark bro~vn. It is 10
oil is soinewltat etcessively dmined and lins mod- to 16 inches tliick. The te.iture of the subsoil rnnges from
s s
(I tlilsi
ei•~tely rapid perinenbility. It holds about 5 inches of silt loani to light silty clay loain. From 5 to 25 percent of
w t r th.at plants caii use. It is easy to «ork. Roots the lo«er subsoil is composed of gravel 1nd stones. As
ra,te to the layer of sa.nd, gravel, and cobblestoues. i11uch ~ 5 percent of some areas consists of Bernliill,
The fertility is medium. Surface ruiioff is slow, and the Dea.qton, or Larkin soils.
Ii rd of erosion is slight. This soil is well di ained and moderltely peime.-Lble. It
bout 80 percent of the a,creage is cultivated; the rest is holds 9 to 11 i»clies of wa.ter tlilt plants c.'tn use. It is
Ii for grazuig, and as farmsteads or suburban lots. easy to Ncorb. IZaot penetration is very deep. The fer-
1 ost of the a,creage is irrigated. Irrigated nreas are used tility is liigh. Surfnce runoff is inedium, nnd the hazard
for orchard fruits 1nd Uerries; cabbabe, corn, cantaloup, of erosion is moderate.
• bers, celery, ~,nd squa,sh; ivhe~.t, oats, ~,nd barley; Aiore than 90 l~ercent of the acrelbe is cultivated; the
1 lfa for lutiy; and ~•nss for seed and pa,sture. 7~rylnnd I'~~ is grazed. l~~liet~t is the cliief crop. It is grown in
treas are used for w ieat, barley, and native bunchgrass. rotation with barley, oats, peas, lentils, nlfalfa, or grass.
Tliere is no difficulty in the use o# machineiy, but the -Al1 gr1s, and grain crops respond to nitro?en; legwles
, el is liard on tillage implements. All crops eacept respoud to sulfur. (Capability unit IIIe-2;1~amy raiige
es respond to nitroben. Some crops respaid to site; not in a~roodland group)
j
, boron, and phosphorus. (Capability unit IIIsr2; Glenrose silt loam, 0 to 5 percent slopes (CpA).-Tlus
r
[,oamy mnge site; not m awoodland group) soil lias a surflce layer 2 to 4 inches tlucker than tliat of
rrison gravelly loam, 5 to 20 percent slopes (Gge).- Glenrose silt loani, 5 to 20 percent slopes. Surface runoff
1' soil hAS a surface la,yer 3 to 5 inches thiuner thln that is slow, and tlie erosion hazard is slinht. Included in map-
)f arrison gravelly loam, 0 to 5 perceilt slopes. IZunoff pii g were small arels of Ulilig and Dea,ryton soils.
is meclium, nnd the erosion 1i1z1rd is moderate. 1'he same crops are grown ns on Glenroso silt loam, 5
iis soil is used in much the sa,me R-ay as Garrison to 20 percent slo pes; in addition, ve;etables are groNrn.
n~ elly loam; 0 to 5percent slopes. (Cnp~bility unit (Cap ~.ility unit IIe-2; Loa,my r~.n;e site; iiot in «ood-
(e-5; Loa~ny ra.nge site; not in a lroodland group) laild gioup)
Garrison very gravelly loam, 0 to 8 percent slopes Glenrose silt loam, 20 to 30 percent slopes (GpC).-This
)-This soil h~,s thiiuzer, more grrn„velly surface layer soil lias a surface layer 3 to 5 inches tliinner than tha~t of
1101s-less GArrison gravelly loam, 0 to 5 percent slopes, and Glenrose silt loani, 5 to 20 percent slopes. Surf~,ce ruuoff
than 5 inches of Avater that plants can use. Tlie is s rnPid,lnd the erosion liazard is severe. About 5percent
;ravel causes exti-eme wetir on tillabe machinery. 11,s of some a.reas consists of Bernhill a,nd Dearyton soils.
il i ns 7 percent of some areas consists of other Garrisoii 'rlie saine crops are browii as on Glenrose silt loain, 5 to
o (Capability unit IVe-5; Shallow ranbe site; not 20 perceut slopes, but ulore of the acreage is in grass and
il nwoodlnnd group) le;umes. (GapaUility unit IIIe-2; Loamy ranbe site;
Garrison very stony loam, 0 to 20 percent slopes ilot in a n-oodllnd group)
i.-This soil holds less than 5 inclies of water tl»,t Glenrose silt loam, 30 to 55 percent slopes (GpD).-This
►1 ts can use, And it is too stony to be cultivated. As soil litis a surface 1~,3~er 3 to 5 inches thinner than tliat of
nuc ias 15 percent of some area.s consists of other Gfl,rrison Glenrose silt loam, 5 to 20 percent slopes. Surfnce ruii-
oil And as much as 2 percent is made up of granite off is rapid, and the erosion hazard is severe. About 3
, ps, percent of some areas consists of Bernliill or Dea,ryton
iis soil is used for grazing. (Capability unit VIs-2; soils. This soil is used only for grazing. (Capability
illow ta nge site; not in a woodland group) lilllt VIPrl ; I~ ortli E sposure r~,nge site; not in a~vood-
land group)
; t•ose Sel'ieS Glenrose gravelly silt loam, 5 to 20 percent slopes
(Gr6).-This soil holds from 7 to 9 inches of Zvater thlt
tie Glenrose series consists of well-drained, mostly pla.nts can use. Small aretis of Bernhill nnd Dearyton
uul-textured soils. These soils formed under grass soi1s were iuclucleA in mappinm.
~l c:~ttered pine trees in glaci~.l till mixed in the' upPer Tliis soil is u~ed in mucli t~ie s~une ~ay as Glenrose silt
~l l vith loess and volcanic ash. Many areas are grave11y loaan, 5 to 20 percent slopes, but yields are less. ( Cap1-
r ston3►. These soils nre nearly level to very steep. The bility unit IV"; Lotimy range site; not in a woodland
iliiu11 prec;ipitation is ~.bout 21 inches, and the frost-free bl•ol1P)
n is about 135 days. Glenrose gravelly silt loam, 20 to 55 percent slopes
rose soils are used for grain, peas, lentils, vegetables, (GrD).-Tliis soil liolds 7 to 9 inches of lvater that plants
1 1 fn, ttnd grass, and for gcx.zuig. can use. Surflce i-tinoff is rapid, and the erosion hazard
enrose silt loam, 5 to 20 percent slopes (Gp6).-Tlzis is seveie. Included in mapping were area,s of Bernhill
lecurs on glaciated uplands in the east-central part of silt loam, 30 to 55 perceiit slopes.
~ • • • . - • ^ . ` • . ' • . . . . . . . , 'l'•' 4~_ • `''•~f: - ' . ' •
. . . . ~ . `~-!2 ' .
• ' • ' e~-- . . 2 +''-~"t .sQ. -'~?~~''~~,.'~c~•,~.~ei%'~: st. : s
y - ~ .z.
74 SOIL SIIRVEY
TABLE F).-I3rief descraptiom of soils dnd tli.eir
,
Depth Classification
'
Map Soil namc Description of soil and site from
srcnbol surface
~ USDA texture
In.
OsC Dragoon st,ony silt loam, 0 to 30 percent Similur to Dragoon silt losm, 0 to 30 perccnt
slopes. slopes, except t,hat the surface laycr is stony.
Os0 Drugoon stony silt loam, 30 to 55 pcr-
cent slopes.
Dv0 Dragoon very rocky comPlcx, 20 to 55 Aragoon part similar to Dragoai silt loam, 0 to
pcrcclit slopes. 30per cent slopc`, acccpt tllat depth to bed-
roc{: ratiges from 10 to '?U i+iclics. Rock ou; {
crop iiuluded iu this couiplcx.
Ek8 Lloika silt loum, 0 to 20 percent slopes. T'Icdium-textarcd, n•cll-dr:►ined soil formed froin U to 24 Silt laam___________
glncial till contniuiuR a largc lcuouut of t•o!-
canic ash in thc s«rfacc lnycr, undcrlniii by 24 to 44 Gravc,lly loam______-
gruvel at depth of 30 to GU inches; occupics 44 to 53 Very gcavelly sandy,
utidulntiug, nioraiurlikc topograpliy. lo1m.
53 to 60 Cravcl___________
EIC I-[oika very stonp silt loam, 0 to 30 pcr- Similar to E loika siltloam, 4 to 20 percentslones,
ccltt slopes. c.eccpt• that thcy arc rcrr stony throughout.
' EJO Lloikn vcry sto►iy silt loam, 30 to 55
pcrcent slopcs.
Em Liudcitt silt loam. Medium-texturcd, somewhat poorly drained, U Lo ?G Silt loain_
alkaliiic soii formed in nlluviiim fram calcar-
cous silt, volcanic ash, and diatanite; depth 26 to 41 '17CTy f111C SAl]dv
to watec tzble flucutates from ncar tha surface lonm.
- to about 6 fect. 41 to 60 Sandy clay loam__:
Fa6 Frecmuai silt loam, 5 to 20 pcrccnt Vcry clcep, inoder;ttcly ivc1I draiiicd upland soils 0 to 22 Silt
slopcs. with medium-tectMrcd sucfacc luycr aaid mcdi-
Fa63 Frceman silt loam, 5 to 20 pcrccut iim or modcratcly 5,ie tc.~tured subsoil; formctd 22 to 72 Silty clay loanL__:
slopcs, severely erocied. froni silt on rolling to hilly uplands.
FaC3 Frcem:ui silt loam, 20 to 30 pcrcent
slopcs, scvcrcly croded.
Fm Fresh watcr marsh. ShnlloW , s~~arnpr, intcrinittcnt ponds and '
fringes 1rouund ~lskes ttuat hlve n fluctu:►ting ~
water tablc. Enginceriiig data is not given, ° •
ns land t•ypc is too variable. .
' GaC3 Gar&cld silty clay loam, o to 30 ncrceiit 1'cry dccp, wcll-cirained soil dcvclopcd in locss 0 to 8 Siltv clav' loam___
slopes, sevcrely eroded. on ridgctops and knobs oii the rolling to hilly 8 to 23 Siltt- cln~_____--:
upiznds iii thc P:►lotisc soil arc:i. 2:3 to 60' Silty rla.• loam___: •
GgA Gnrrison grnvelly loam, 0 t,o 5 pcrcent Grnvellv, nicditun-tcxturcd, somcwluit exces- 0 to 15 Grarcllv lo:un___: ,
&lopes. sivel~, drai»ccl soils fonnecl in grttvelly glaieiAl 15 ta 44 A'ery grnrellr lo • .
Gg8 Garnson gravcUy loam, 5 to 20 percent outwash matcrial from n vnriety of Rcid, 44 Lo 60 Sund, gr.1vcl, and.
slopes. ibiicous p:irent rock; on ne.lrlv lex•el Lo mod- cobblestanes. -
critcly r-loNiug tcrr.tces; depLli to mixtiirc of `
' sand, gr:ivel, Rnd cobblestones mnges from
2!•s to 3 feet-.
Gm6 Cflrrison vecy gntvelly loam, 0 to 8 Similar to Garrison gra%•elly loitm, cacept Ehat 0 to 15 Vecy gravelly 1.
pcrcent slopes, t.hc siu facc larcr i: rcry gr:ivelly. 15 to 44 A'erv grnvclla t
44 to 60 Sand, grnvcl, and
cobblestones•
GnB Garrison very stouy tonin, 0 to 20 Siinilar to G:irrisou gr:irelly lotim, cxcept that ;
pcrccnt slopes* tltc su~~f:icc l:ircr is ~•cry stonr.
GpA Clenrasc silt loam, 0 to 5 percentslopes. Vcr~• dcc•p, »icctiuiu-t~•etured, ivell-drained soils 0 to 72 Silt loain_----•.
Gp6 Glciirosc silt loam, 5 to 20 percentslopes. foriucd from acid i iieous glacial till; surface
GpC Clenrosc silt loam, 20 to 30 percent la~~er inftucnccti bi•~ocss and volcanic ash; on
slopes. gcntlr rollitig to stccp uplands.
Gp0 Glcnrosc silt loam, 30 to 55 percent
sloncs.
..at.r~.~~t-.s.vc.:~trr✓.•••Yr,S:.f. Zr~ a...Q.r~.-
. . . ~ . _ • _ ~ -~:p,-; ~ . ~ ?=r,~l•: : 's"; ~ I
• . - • ' . . , . . . . . • • . =ly . . ~ I•.~.' ' ~ • ~ J. ~
r~ • ~
P • ~
SPOKANE COIINTY, WAS~GTON 75
.
,starna,Md physic¢l and c1temZca,l properties-Continued
C;gcation--Coi►tiiiued Pcrcctitagc; ppssing sic%•c-- pvailablc ~
~ Pcrincability water Rcaction Dispcrsion Shrink-swcll ;
~o. 4 -No. 10 No. 200 alpzcity (1:5 clilution) potential
lified AASHO (9.7 mm.) (2.0 mm.) (0.074
inin.)
lu. lxs hr. A. ptr irt. o/ aoil p//
I
\ CT,---- a-~------ S51o95 80 iu 95 60(o70 ll. S to 2.5 O. 17 to (1. 21) ti. 1 to ti. 5 11 ihii Low to mod-
rratAe.
S. A`4 7:3 to 8.5 40 to SU 33 to :30 Q. S to .5 0. 12 to 4. 14 G. 1 l06. G lligli------- I.oa•.
C. A-2------ :;c► to Gtl 'l(1 to :,cf to tc~ 5.0 to ltl. t► 0. tl(i to t1. tr1 G. l la 7. :i tii~;t~--- .oa•.
I p-] 2-5 to :i:, 10tu '?11 0 to :i >IU U. 04 to c1. Uc► li. li 1a 7. :i 11 igli I.ow.
X CL____ A-4------ 95 to 100 'JU i.o lU0 90 to 9:i O. 8 to 2 a ll. 17 W0.20 i. S to 9. 0 lligli------- l.ow to mocl-
~1I.-------- A-4------ 95Iu 100 !)U ia 100 fill to iU 8 to :i Q. 17 4o U. ?lt 7.4 to 8.4 Aloclrratc:--- i.ow.
C~----_- A-fi------ J;i to 100 90 to 95 85(1090 q. 2 to 0. $ O. 17 to U. 20 G. fi to i. :i I.otr------- llodcratc.
at4-CI.-_ A-4------ 95 to 100 g(1 to ltlq 80 to 90 Q. 2 to (l. 8 A. 17 io 0. 20 G. G 1nr. :i ltoclc~i:~tr.--- Low tq mod-
c~r:~tr..
Cl A-G 03 to 100 90 to 100 80 to 90 <0. 0i Q. 17 tol1. 2(1 G. G ta 7.:i l.ow A•fodcratc.
k
C A-6------ 95 to lOQ JO to 100 90 to 95 Q. 2 to 0. S U. li to Q. 16 G. fi to 7. 3 Low_______ A4odcrntc.
r l------- A-i------ 95 to 100 qO to lOO SiA 1A 95 0. tf:i to t). 2 U. 14 to 0. 1 i fi. 6 to 7.3 T.ow I•Iigli.
C A-f------ 05 to 100 41U to lUU JO to 93 U. 2 to 5 (l. li to 0.2l1 G. G to 7. 3 Low rsodcratc.
xM A-#------ 6 3 to Sa 40 to RO 35 to 50 0.8% to 2. 5 0. 13 to (l. 14 6.6(o 7.3 11'fodci.lrc i,ow.
(I I A-2------ 45 to 65 30 to GO 5 to l:i 2.5 ro;i. l) U. 08 to (l. 10 G. G to i. 3 Maclcr,ite___ Low.
V A-1------ 25 to 3:3 10 to 20 0 to :i >10 0. 04 to 0. UG G. G to 7. 3 If igh------- Low.
~
G' A-2------ 30 to GO 20 l.0 50 5 to 15 2. 5 to 5. 0 0. 0S to A. 10 G. 1 to G. G AZodcrate___ Low.
A-2------ 45 to 65 30 to 60 5 to 15 2. 5 to 5. 0 U. US to A. 10 G. G to i. 3 Modcratc___ Low. ~
~r•-•----- A-1------ 23 to 35 10 to 20 0 to 5 >10 0. 44 to 0. OG G. G to 7.3 1Iigh------- Lflw.
i
I
i
~~''CL---- SO to 95 75 to 95 GO to 85 0. 3 to 2. 5 0. 17 to 0.20 G. 1 to 3 111oderatc__ Lo~v to
moderate.
~
t
.r a
,
~ I.. . . . " - . . . . - . . • . • ^ . . • • • r . . ; . . • • . J• . . . : 1. . . , . .
1
i~ 92 sorr. svRVEY
~
TABLE 7.-In,terpreta,tion of engitiF,
Suitability as sourcc of- Soil fcutures affccting-
Soil scrics or typc, Furm pont
and map symbols
Topsoil Sand 1 Grarel ~ Itoad fill Iiighway location Dikes or lcvecs
Resen•oir a
,
Dragoon (DrC, Good to Not suit- Not suit- Fair to Moderate to very liigh Low st-ability; Moderate to
' DsC, OsD, poor: able. able. good. susceptibility to semipervious to moderatel_
~ pv p), frost action; mod- impervious rapid per).
j erute to modcratelr when com- abilitv.
. rapid pcrmeabilitv ; pactcd; low to
low to inodcratc moderntc
shriuk-swcll shri i ik-swcll
' potcntiAl, potentinl.
Eloika (Ek6, EIC, Fair______ Not suit- Suit:iblc at Goo&____ Moderate to ltigli sus- Low Atibility; Moderateto
' E10). able. deptli ccPtibiliLy to trost semipcrvious to rnpid peri,
` greater action; modcratc Lo imrcrriotis ability.
than GO very rnpid Pcrmc- wlicii compact-
hichr,. ability. • low to mod- ed; low to mod-
cratc siiriiik-swcll crstc shrink-
Potcnt-i:tl. swcll potentinl.
Eindrnt silt loam I'air____ Not suitn- Not suita- Poor___ A'ery higiisusceptibil- Low st~zbility; ini- Moderate to
i (Em), ble. ble. ity to frost action; pervioiis «lhen modcrait•I:
modr.rate to mod- compactecl; low slow periit
erately glow perme- to inodcratc: abiliti•.
• ubility• low to mod- shrin;;-swcll
eratc s6ink-sa•ell potetitinl.
potcntial; saturatcd
tn wintcr and spring.
' Freeman (Fa6, Fair to Not suita- Not suita- Poor_____ Moderate to very liigli Moderate stabil- Moderatel-,- •
• FaB3, FaC3). poor. ble. ble. suscept+bility to itp ; impervious to ~~er}~ sl~
' frost action; modcr- ~~•hen complct- permeabll~
~ ately slow to ver.- ed; low to mod-
slow permcability; cratc slirink-
. lo« to moderatc swell pot.ential;
shrink-sn•ell poteu- soils crack whcn
tial; szturated in dry.
i[
, spring-
i
' Garfield (GaC3)___ Fair to NOt suita- Not suita- Poor_____ Moderate tfl very high Moderate stabil- Moderate to
good, ble. ble, susceptibility to frest ity; impervious slow perm•
' acLion; moderutc to %%•licn compACt- ability.
slow permeabilitv; ed; moderate to
moderatc to lugh high shrink-
, shrink-s«•ell paten- swell potential.
tial.
~ Garrison (GgA, I'air_ Not suit- Good below Exccllent_ Slight to no suscepti- Moderate stabil- Moderate to
GgB, Gm6, able. surface bility to frost action; ity; pervious very rapic'.
Gn6). layer. moderate to very when coin- pcrmeabili
rapid pcrmeability; pacted; low
low shrink-swcll shrink-swell
potential. potential.
See footnote at end ot table.
!
{
~ -
I
~
I
• . . _ . ' . . ' . . . . . . . t~ ~{,"~.3.~i4L1siS~Y~~~.n~~~~~1~/~t.I
. • . . . . ~~J-'i , •
r
~y" • .
, SPOSAIr'E COUN'Y`T, WASxINCTOx .93
roperiies of soils-Continued
~ Soil fcatures affecting-Continucd
i Fnrm ponds-
Coittinucd Agriculturtil Tcrraces and Scwagc disposal
draitiftge Irrigation dirersions Wztcnrays fic:ids Trafficability
, rp,baiikmcnt
} ~ry lovc shear 'Moderute to 11•Loderate in- T.ow resistancc Low resistaaice to \Iodcrate to Vcry low shcar
; Wcngth, semi- modcrately takc rate; tq crosion; crosion; inod- modcrntcly strcngth; low
, pcn•ious to im- rupid pcrrnc- moderatc mocieratc to cr.ltc «•ntcr- rnpid pcrmc- load-ctury ing
Pem'101ts when ahility. «ntcr-i►olding moderltelv holding cap1c- .nbility; mocl- cupncity;
Mnpxctcd; n1e- cnplcity. sapid pcrmo- itv: rcgctittioil ei:►tc to n od- modcrute to
ditim conipccss- ability. dif&cult to crntcly r:►pid modcratcly
i~~~ty, law cstnl:lish ctxccpt watcr-lioldhig rapid perme-
~ Finbilil~. ai 1)ragoou capacity. lbility.
silt lonro.
a• shcar strength; Afodcrate to Moderntc; to Atodrr.ite resist- r[odrrate resist- \tadcrlte to Low sl►car
remipcrvious to vcrv rapicl modei-atcly ancc to cro- :uicc to crosion; vcry rurid strengtli• mod-
~napcrvious n'Ucn pcr~ncability. rsipid ii~take sion; modcr• modcr:~te ~aatcr- pennc.nbility; crute to high
eompacted; slight mte; mocicr- ntc to rery holditis ca• modcrute load-currying
compressibilitr; ate w.~tcr- r.ipicl pcrnie- plcitr; vegCtu- watcr-liolcling capacity; mod-
!on stabilitr. holding ca- ability. Lioi► cli(iicult to cnpacitv. cratc to very
p;ticity. rstablish cxcept rnpid pcrmc-
oti I:loika silt ability.
loa1n.
cry loa' sluear Modcratc to 14odcratc to \loclcratc resist• Moclcrntc resist- AIodcr.it.c to Ntcry loAv shcar
4rcngLh; impcr- modrr:titcly inodcrntcly ance to cro- ancc to crosion; mocleratcly strtngth; inod-
rious Whcn com- slow ptrmc- slow intnkc sioii; modcr- vcry liigli witrr- slo«=pcnno- cratc to lotv
~ pac#,cd; inoderlte ability; satu- rate; vcry ate to nioder- lioldiiig c.ipac- ability;very load-currying
to hibfi conipress- rnted in n•in- liigh water- atrlV sloW i6y; excc-pt for liigh watcr-hold- c.lplcity; mod-
ibiULp; moderate ter and holding ca• perme.lbility. s:ilt-tolcrwit ins cnp:►citp; ci•nte to rnod-
dtability; cracks spriiig. pacitv, specics, vcgeta- s:iturntcd in crstc:ly slow
whcn dn•. tion ditlicult to «•+sitcr atici pcrmcability.
' establish. spcing.
low sltcar Moderately Moderatcly Niodernte resist- Moderatc resist• A'Ioder.titcly Very low shear
drength; impcr- Qlow to very slow to slorv ancc to ero- attce to erosion; slow to vcry strength; mod-
. vbus n•hen com- slow permc- intake rate; sion; moder• very ]iigh water- slow pe'rmc- crate load-
paeted; mediuni ability; witu- very high at.ely slon' to holding cnpac- nbility; very cnrrying ca-
eompressibility; rlted in water-holdino vcrr slow pc:r- ity; vcgctltion higli watcr- pacity; mod-
tnodcratc stabil- spri►ig. capacity. mcabilitr. fnirlv casy to holding ca- cratcly, slow to
Ity; soils crlck establish. pacity; satu- very slow
~rbcn drv. rated in pcrmcability.
' spring.
low shr:ir rioderatc to Slow iuGa,i:c A'Iodcratc resist- 2\1odcrate resist- TToclcrate to Vcry low shcar
ngl,l►; iniper- slo~~• perme• rate; very ance to cro- nnce to erosion; slo~v Perme- strcn th; mod-
sttr
%~bu8 ~~•li~:~~ rom- nbility, liigh water- sion; inoder- vcry higti ability; very erate~oad-
paetc:cl; tnestittm to holding ca- ate to s1oR- wlter•liolding hi li k•ater- carrying ca-
hf~b cornprc~sibil- pacity. pcrmeability. capacityT; holding c1- pacity; mod-
tty• m«lcrat•c veget;xtioii pA.city. erate to slow
~1a~iliL • soil fnirly cnsNto permeability.
y~ est.ablish.
eracke o at~c~i drv.
kbtheursLrengtlY; 314odernte to Itapid intake Modcrate rcsist- Afodcrntc resist- Afoderate to High shear
pctvfous 'vrhen very* rapid rate; moder- unce to ero- auce to erosion; very rxpid strength; high
WmPacw; slight perineability. ate to low sion; modcr- modemte to low permeability; load-carrying
ftmIinssibility' • water-holding atc to very water-holding moderate to capacity;
modrn~tc ,t:~- capacity, rnpid pcrme- c.lpacit•y; vege- low water- moderate to
b(UtY• ability. tnt.ion difficult holding ca- vcry rspid
to estn.blish ai pacity. permeability.
verr stony loam,
fairly casy on
otl►cr soils.
s. •t:,_
~
r
Appendix B
Hydrologic and Hydraulic Calculations
~ -n
Outstanding . ,
DAVID EVANS AND ASSOCIATES,
~
~
~
1
208 Calculations
1 sWALE A (2.5? x 25')
208 Volume Req,.irea:
1,212 S.F. ACPl24 Y51 C.F. _
208 Volume Provided:
. ~
(0.5') (62.5 S.F.) + (0.375 C.F.IL,F.) (55 L.F.)
~ = 52 C.F. Storm Volume Provided:
~ = (0-67') {62.5 s.F.) + (0.67 C.F./L.F.) (55 L.F.)
_ 79 C.F.
' SWALE B (6' x 19' )
20$ Required:
' 1619 S.F. ACPI24 = 67 C.F.
208 Provided: (0.5') (114 S.F.) + (0.25 C.F.1L.F.) (50 Lr.F.)
= 70 C.F.
Storm Volume Provided:
~ _ (0.67') (114 s.F.) + (0.45 C.F./L.F.) (so L.F.) -
_ 99 C.F.
sWALE C (2.s= x 30')
20$ Volume Required:
1464 S.F. ACF124 = 61 C.F.
208 Volume Frvvided.
(0.5') (75 S.F.) + (0.375 C.F.1L.F.) (65 L.F.)
_ 94 C.F.
~ Storrn Volume Provided:
{0,67'} (75 S.F.) + (0.67 C.F.1I1.F.) (65 L.F,)
= 94 C.F.
❑rainage Report for Bradley Heights 3ubdivision Appendix Bi
MA HAOOTIDRAIHREP713.DOC 07114199
~
~
~ SWALE D (6'X 1 6' .
)
208 VOll1tT1e ReqU1red:
~
14Dd S.F. ACP124 _ 59 C.F.
208 Volume Provided:
(0.5') (96 S.F.) + (0.25 C.F./L.F.) (44 L.F.)
= 59 C.F.
Storm volu.me provided: -
(Q.G?') C96 S.F,O + (0.45 C.F./L.F.) (44 L,F.)
_ 84 C.F.
SWALE E (2.5' X 45') -
20$ Volume Required:
2,192 S.F. ACPl24 = 91 C.F. ~
20$ Valume Provided:
~
-
. (0.5") (112.5 S.F.) + (0.375 C.F./L.F.) (95 L,F.)
= 92 C.F.
Storm Volume Prvvided: .
(0.67') (112.5 S.F.) + (0.67 C.F./L.F.) (95 L,F.)
- = 139 C.F.
~
~WALE F (6'X 30')
~ 208 Volume Required:
2,597 S.F. ACP124 = 108 C.F,
20$ Valume Provided
(o.s') (180 S.F,) + (0.25 C.F./L.F.) (72 L.F.)
= 108 C.F.
st~~ ~~lume providea
(0,671) (150 S.F.) + (0.45 C,F.IL.F,) (72 L.F.)
= 1 52 C.F. ,
Drainage RepQrt for Bradley Heights Subdivision Appendix B2
MAHAOoTIoRxirvREP71s, DoC 07114M
,
,
SWALE G(Identical to Swale H)
208 Volume Required:
3,690 S.F. ACP/24 = 154 C.F.
208 Volume Provided:
(0.5') (309 S.F.) + (0.375 C.F./L.F.) (85 L.F.)
= 186 C.F. -
Storm volume provided:
(0.67') (9309 S.F.) + (0.67 C.F./L.F.) (85 L.F.)
= 263 C.F.
~
~
Drainage Report for Bradley Heights Subdivision Appendix B s
MAHAOOT/DRAINREP713.DOC 07/14/99
, •
DAVID EVANS AND ASSOCIATES
BOWSTRING METHOD (TEN YEAR STORM DESIGN) PROJECT: BRADLEY HEIGHTS
DETENTION BASIN DESIGN PROJECT NO: MAHA0005
BASIN: 1
' NUMBER OF DRYWELLS PROPOSED DESIGNER: DOUG BUSKO, P.E.
1 Single (type A) 0 Double (type B) DATE: 13 Jul 99
Total Area (calc.) (see H 1) 0.37
, Time of Conc. (calc.) (see H 1) 6.83
Composite C" (calc.) (see H 1) 0.40
Time of Conc. (min) 6.83
Area (Acres) 0.3708
C' Factor 0.40
Impervious Area (sq. ft.) 0
Volume Provided 208: 0 storm: 178
Outflow (cfs) 0.3
Area * C" Factor 0.15
' #1 #2 #3 #4 #5 #6 #7
Time Time Intensity Q dev. V in V out Storage
lnc. Inc.
1 (min.) (sec.) (in./hr.) (cfs) (cu. ft.) (cu. ft.) (cu~ ft.)
(#1 *60) (A*C*#3) (Outf.*#2) (#5 #6)
6.83 409.54 2.84 0.42 231 122.86 108
5 300 3.18 0.47 190 90 100
10 600 2.24 0.33 246 180 66
15 900 1.77 0.26 273 270 3
20 1200 1.45 0.22 288 360 -72
25 1500 1.21 0.18 294 450 -1S6
' 30 1800 1.04 0.15 299 540 -241
35 2100 0.91 0.13 302 630 -328
40 2400 0.82 0.12 309 720 -41 l
45 2700 0.74 0.11 312 810 -498
50 3000 0.68 0.10 317 900 -583
55 3300 0.64 0.09 326 990 -664
60 3600 0.61 0.09 338 1080 -742
65 3900 0.60 0.09 359 1170 -811
70 4200 0.58 0.09 373 1260 -887
' 75 4500 0.56 0.08 385 1350 -965
80 4800 0.53 0.08 388 1440 -1052
85 5100 0.52 0.08 404 1530 -1126
90 5400 0.50 0.07 411 1620 -1209
' 95 5700 0.49 0.07 424 1710 -1286
100 6000 0.48 0.07 437 1800 - l 363
DRAINAGE POND CALCULATIONS
Grassy swale'208' pond storage volume
= Impervious Area x.5 in./ 12 in./ft. = required: 0 cu. ft.
provided: 0 cu. ft. NO GOOD
DRYWELL REQUIREMENTS - 10 YEAR DESIGN STORM
Maximum storage by Bowstring = required: 108 cu. ft.
provided: 178 cu. ft. OK!
Number and type of drywells required = 1 SINGLE
0 DOUBLE
DAVID EVANS AND ASSOCIATES
PROJECT: BRADLEY HEIGHTS DESIGNER: DOUG BUSKO, P.E.
PROJECT NO: MAHA0005 DATE: 13-Ju1-99
BAS1N: 1
'
TIME OF CONCENTRATION (min) Surface Areas „Cit
Tc (overland) Tc (gutter) Description (acres)
Ct = 0.15 L2 = 0 Grass, House, Road 0.3708 0.40
Z 1= 0 0.0000 0.00
L 1(A) = 145 Z2 = 0 0.0000 0.00
N(A) = 0.4 B= 0 0.0000 0.00
S(A) = 0.01 n= 0 0.0000 0.00
s = 0 0.0000 0.00
Tc (A) = 6.83 d= 0 0.0000 0.00
Total A Comp "C"
L 1(B) = 0 Tc (gu) = 0.00 0.37 0.40
N(B) = 0.016 Tc(A+B) = 6.83
S(B) = 0.008 Q=C*I*A= 0.42
Tc(tot,) = 6.83 Q(est.) = 0.00
Tc (B) = 0.0 Intensity = 2.84
A= 0
WP = #DIV/O!
R = #DIV/O!
V = #DIV/0!
Tc (total) = Tc (overland) + Tc (gutter) Tc(gu) _ #DIV/O!
Tc (overland) = Ct*(L 1 *N/S^0.5)^0.6) Q(est) _ #DIV/O!
Ct = 0.15
L 1= Length of Overland Flow Holding = 0.00
N= friction factor of overland flow (.4 for average grass cover)
S= average slope of overland flow
Tc (gutter) = Length (ft.)/Velocity (ft./sec.)/60
B= Bottom width of gutter or ditch
Z1 = inverse of cross slope one of ditch
Z2 = inverse of cross slope two of ditch
d= depth of flow in gutter (estimate, check estimate with Flow)
' Area = d*B+d^2/2*(Z1+Z2)
Wetted perimeter = B*d+(1 /sin(atn(1 /Z 1))+I /sin(atn( I/Z2)))
Hydraulic Radius = R= Area/Wetted Perimeter
Velocity = 1.486/n*R^.667*s^.5
Flow = Velocity*Area
n = 0.016 for asphalt
s= longitudinal slope of gutter
' '
'
DAVID EVANS AND ASSOCIATES
BOWSTRING METHOD (TEN YEAR STORM DESIGN) PROJECT: BRADLEY HEIGHTS
DETENTION BASIN DESIGN PROJECT NO: MAHA0005
BASIN: 2
NUMBER OF DRYWELLS PROPOSED DESIGNER: DOUG BUSKO, P.E.
0 Single (type A) 1 Double (type B) DATE: 13-Ju1-99
Total Area (calc.) (see H 1) 0.57
Time of Conc. (calc.) (see H 1) 8.65
Composite "C" (calc.) (see H 1) 0.40
Time of Conc. (min) 8.65
Area (Acres) 0.5672
C' Factor 0.40
Impervious Area (sq. ft.) 24707.232
Volume Provided 208: 0 storm: 178
Outflow (cfs) I
Area * C" Factor 0.23
#1 #2 #3 #4 #5 #6 #7
Time Time Intensiry Q dev. V in V out Storage
Inc. Inc.
' (min.) (sec.) (in./hr.) (cfs) (cu. ft.) (cu. ft.) (cu. ft.)
(#1*60) (A*C*#3) (Outf.*#2) (#5-#6)
8.65 518.73 2.49 0.57 393 518.73 -125
5 300 3.18 0.72 290 300 -10
10 600 2.24 0.51 395 600 -205
15 900 1.77 0.40 432 900 -468
20 1200 1.45 0.33 453 1200 -747
25 1500 1.21 0.27 460 1500 - l 040
30 1800 1.04 0.24 466 1800 -1334
35 2100 0.91 0.21 470 2100 -1630
40 2400 0.82 0.19 479 2400 -1921
' 45 2700 0.74 0.17 483 2700 -2217
50 3000 0.68 0.15 490 3000 -2510
55 3300 0.64 0.15 SOS 3300 -2795
' 60 3600 0.61 0.14 523 3600 -3077
65 3900 0.60 0.14 555 3900 -3345
70 4200 0.58 0.13 576 4200 -3624
75 4500 0.56 0.13 594 4500 -3906
80 4800 0.53 0.12 598 4800 -4202
85 5100 0.52 0.12 622 5100 -4478
90 5400 0.50 0.11 633 5400 -4767
' 95 5700 0.49 0.11 653 5700 -5047
100 6000 0.48 0.11 673 6000 -5327
DRAINAGE POND CALCULATIONS
Grassy swale '208' pond storage volume
= Impervious Area x.5 in./ 12 in./ft. = required: 1029 cu. ft.
provided: 0 cu. ft. NO GOOD
DRYWELL REQUIREMENTS - 10 YEAR DESIGN STORM
Maximum storage by Bowstring = required: -10 cu. ft.
provided: 178 cu. ft. OK!
Number and type of drywells required = 0 SINGLE
1 DOUBLE
DAVID EVANS AND ASSOCIATES
PROJECT: BRADLEY HEIGHTS DESIGNER: DOUG BUSKO, P.E.
PROJECT NO: MAHA0005 DATE: 13-Ju1-99
BASIN: 2
, TIME OF CONCENTRATION (min) Surface Areas "C"
Tc (overland) Tc (gutter) Description (acres)
Ct = 0.15 L2 = 0 Grass, House, Road 0.5672 0.40
Z 1= 0 0.0000 0.00
L 1(A) = 215 Z2 = 0 0.0000 0.00
N(A) = 0.4 B= 0 0.0000 0.00
S(A) = 0.01 n= o 0.0000 0.00
S = o 0.0000 0.00
' Tc (A) = 8.65 d= 0 0.0000 0.00
Total A Comp "C"
L 1(B) = 0 Tc (gu) = 0.00 0.57 0.40
N(B) = 0.016 Tc(A+B) = 8.65
S(B) = 0.008 Q=C*I*A= 0.57
Tc(tot.) = 8.65 Q(est.) = 0.00
Tc (B) = 0.0 Intensity = 2.49
A= 0
WP = #DIV/0!
R = #DIV/0!
' V = #DIV/0!
Tc (total) = Tc (overland) + Tc (gutter) Tc(gu) _ #DIV/0!
Tc (overland) = Ct*(L1 *N/S^0.5)^0.6) Q(est) _ #DIV/0!
Ct=0.15
Ll = Length of Overland Flow Holding = 0.00
N= friction factor of overland flow (.4 for average grass cover)
S= average slope of overland flow
Tc (gutter) = Length (ft.)Nelocity (ft./sec.)/60
B= Bottom width of gutter or ditch
Z 1= inverse of cross slope one of ditch
Z2 = inverse of cross slope two of ditch
d= depth of flow in gutter (estimate, check estimate with Flow)
' Area = d*B+d^2/2*(Zl+Z2)
Wetted perimeter = B*d+(1/sin(am(1/Z1))+l/sin(atn(1/Z2))}
Hydraulic Radius = R= Area/Wetted Perimeter
Velocity = 1.486/n*R^.667*s^.5
Flow = Velocity*Area
n = 0.0 16 for asphalt
s =longitudinal slope of gutter
'
'
DAVID EVANS AND ASSOCIATES
' BOWSTRING METHOD (TEN YEAR STORM DESIGN) PROJECT: BRADLEY HEIGHTS DETENTION BASIN DESIGN PROJECT NO: MAHA0005
BASIN: 3
NUMBER OF DRYWELLS PROPOSED DESIGNER: DOUG BUSKO, P.E.
0 Single (type A) 1 Double (type B) DATE: 13-lu1-99
Total Area (calc.) (see H 1) 0.72
Time of Conc. (calc.) (see Hl) 9.07
Composite "C" (calc.) (see H 1) 0.40
Time of Conc. (min) 9.07
Area (Acres) 0.7238
C' Factor 0.40
Impervious Area (sq. ft.) 0
Volume Provided 208: 0 storm: 291
Outflow (cfs) 1
Area * C" Factor 0.29
ttl #2 #3 #4 #5 #6 #7
Time Time Intensity Q dev. V in V out Storage
Inc. Inc.
(min.) (sec.) (in./hr.) (cfs) (cu. ft.) (cu. ft.) (cu. ft.)
(#1*60) (A*C*#3) (Outf.*#2) (9546)
9.07 54437 2.41 0.70 510 544.37 -34
5 300 3.18 0.92 370 300 70
10 600 2.24 0.65 509 600 -91
15 900 1.77 0.51 556 900 -344
20 1200 1.45 0.42 581 1240 -619
25 1500 1.21 0.35 590 1500 -910
' 30 1800 1.04 0.30 598 1800 -1202
35 2100 0.91 0.26 602 2100 -1498
40 2400 0.82 0.24 614 2400 -1786
45 2700 0.74 0.21 618 2700 -2082
50 3000 0.68 0.20 627 3000 -2373
55 3300 0.64 0.19 646 3300 -2654
60 3600 0.61 0.18 668 3600 -2932
65 3900 0.60 0.17 710 3900 -3190
70 4200 0.58 0.17 736 4200 -3464
75 4500 0.56 0.16 760 4500 -3740
' 80 4800 0.53 0.15 765 4800 -4035
85 5100 0.52 0.15 796 5100 -4304
90 5400 0.50 0.14 808 5400 -4592
' 95 5700 0.49 0.14 835 5700 -4865
100 6000 0.48 0.14 860 6000 -5140
DRAINAGE POND CALCULATIONS
Grassy swale'208' pond storage volume
= Impervious Area x.5 in./ 12 in./ft. = required: 0 cu. ft.
provided: 0 cu. ft. NO GOOD
DRYWELL REQUIREMENTS - 10 YEAR DESIGN STORM
Maximum storage by Bowstring = required: 70 cu. ft.
provided: 291 cu. ft. OK!
Number and type of drywells required = 0 SINGLE
1 DOUBLE
'
DAVID EVANS AND ASSOCIATES
PROJECT: BRADLEY HEIGHTS DESIGNER: DOUG BUSKO, P.E.
PROJECT NO: MAHA0005 DATE: 13-Ju1-99
BASIN: 3
'
TIME OF CONCENTRATION (min) Surface Areas f,Cil
Tc (overland) Tc (gutter) Description (acres)
Ct = 0.15 L2 = 0 Grass, House, Road 0.7238 0.40
Z 1= 0 0.0000 0.00
L 1(A) = 233 Z2 = 0 0.0000 0.00
N(A) = 0.4 B= 0 0.0000 0.00
S(A) = 0.01 n= 0 0.0000 0.00
s = 0 0.0000 0.00
Tc (A) = 9.07 d= 0 0.0000 0.00
Total A Comp "C"
L 1(B) = 0 Tc (gu) = 0.00 0.72 0.40
N(B) = 0.016 Tc(A+B) = 9.07
S(B) = 0.008 Q=C*I*A= 0.70
Tc(tot.) = 9.07 Q(est.) = 0.00
Tc (B) = 0.0 Intensity = 2.41
A= 0
WP = #DIV/0!
R = #DIV/0!
V = #DIV/0!
Tc (total) = Tc (overland) + Tc (gutter) Tc(gu) _ #DIV/0!
Tc (overland) = Ct*(Ll*N/S^0.5)^0.6) Q(est) _ 9DIV/0!
Ct=0.1S
L 1= Length of Overland Flow Holding = 0.00
N= friction factor of overland flow (.4 for average grass cover)
S= average slope of overland flow
Tc (gutter) = Length (ft.)/Velocity (ft./sec.)/60
B= Bottom width of gutter or ditch
Zl = inverse of cross slope one of ditch
Z2 = inverse of cross slope two of ditch
d= depth of flow in gutter (estimate, check estimate with Flow)
' Area = d*B+d^2/2*(Z 1+Z2)
Wetted perimeter = B*d+( l/sin(atn( i/Z 1))+1 /sin(atn(1 /Z2)))
Hydraulic Radius = R= Area/Wetted Perimeter
Velocity = 1.486/n*R^.667*s^.5
Flow = Velociry*Area
n = 0.016 for asphalt
s= longitudinal slope of gutter
DAVID EVANS AND ASSOCIATES
BOWSTRING METHOD (TEN YEAR STORM DESIGN) PROJECT: BRADLEY HEIGHTS
DETENTION BAS1N DESIGN PROJECT NO: MAHA0005
BASIN: 4
NUMBER OF DRYWELLS PROPOSED DESIGNER: DOUG BUSKO, P.E.
' 0 Single (type A) l Double (type B) DATE: 14-Ju1-99
Total Area (calc.) (see Hl) 1.08
Time of Conc. (calc.) (see H l) 10.62
Composite "C" (calc.) (see H 1) 0.40
Time of Conc. (min) 10.62
Area (Acres) 1.0822
C' Factor 0.40
impervious Area (sq. ft.) 0
Volume Provided 208: 0 storm: 0
' Outflow (cfs) 1
Area * C" Factor 0.43 .
e
#1 42 #3 #4 95 #6 #7
' Time Time Intensity Q dev. V in V out Storage
lnc. Inc.
(min.) (sec.) (in./hr.) (cfs) (cu. ft.) (cu. ft.) (cu. ft.)
(41 *60) (A*C*#3) (Outf.*#2) (#5-#6)
10.62 637.30 2.18 0.94 806 637.30 169
5 300 3.18 1.38 553 300 253
10 600 2.24 0.97 780 600 180
15 900 1.77 0.77 856 900 -44
20 1200 1.45 0.63 889 1200 -311
25 1500 1.21 0.52 899 1500 -601
30 1800 1.04 0.45 908 1800 -892
35 2100 0.91 0.39 913 2100 -1187
40 2400 0.82 0.35 929 2400 -1471
45 2700 0.74 0.32 934 2700 766
50 3000 0.68 0.29 947 3000 -2053 55 3300 0.64 0.28 974 3300 -2326
60 3600 0.61 0.26 1008 3600 -2592
' 65 3900 0.60 0.26 1069 3900 -2831
70 4200 0.58 0.25 1109 4200 -3091
75 4500 0.56 0.24 1143 4500 -3357
' 80 4800 0.53 0.23 1151 4800 -3649
85 5100 0.52 0.23 1197 5100 -3903
90 5400 0.50 0.22 1216 5400 -4184
95 5700 0.49 0.21 1255 5700 -4445
' 100 6000 0.48 0.21 1292 6000 -4708
DRAiNAGE POND CALCULATIONS
Grassy swale '208' pond storage volume
= Impervious Area x.5 in./ 12 inJft. = required: 0 cu. ft.
provided: 0 cu. ft. NO GOOD
DRYWELL REQUIREMENTS - 10 YEAR DESIGN STORM
Maximum storage by Bowstring = required: 253 cu. ft.
provided: 0 cu. ft. NO GOOD
Number and type of drywells required = 0 SINGLE
1 DOUBLE (Existing)
I DAV
ID EVANS AND ASSOCIATES
PROJECT: BRADLEY HEIGHTS DESIGNER: DOUG BUSKO, P.E.
' PROJECT NO: MAHA0005 DATE: 14-Ju1-99
BASIN: 4
' T[ME OF CONCENTRATION (min) Surface Areas "C"
Tc (overland) Tc (gutter) Description (acres)
Ct = 0.15 L2 = 0 Grass, House, Road 1.0822 0.40 .
Z 1= 0 0.0000 0.00
L 1(A) = 303 Z2 = 0 0.0000 0.00
' N(A) _ 0.4 B= 0 0.0000 0.00
S(A) - 0.01 n 0. 0.0000 0.00
s = 0 0.0000 0.00
' Tc (A) = 10.62 d= 0 0.0000 0.00
Total A Comp "C"
L1(B) = 0 Tc (gu) = 0.00 1.08 0.40
N(B) = 0.016 Tc(A+B) = 10.62
S(B) = 0.008 Q=C*I*A= 0.94
Tc(tot.) = 10.62 Q(est.) = 0.00
Tc (B) = 0.0 Intensity = 2.18
' A= 0
WP = #DIV/O!
R = #DIV/O!
' V = #DIV/O!
Tc (total) = Tc (overland) + Tc (gutter) Tc(gu) _ #DIV/O!
Tc (overland) = Ct*(Ll *N/S^0.5)^0.6) Q(est) _ #DIV/O!
Ct=0.15
L 1= Length of Overtand Flow Holding = 0.00
N= friction factor of overland flow (.4 for average grass cover)
S= average slope of overland flow Tc (gutter) = Length (fr.)/Velocity (ft./sec.)/60
B= Bottom width of gutter or ditch
Zl = inverse of cross slope one of ditch
' Z2 = inverse of cross slope two of ditch
d= depth of flow in gutter (estimate, check estimate with Flow)
Area = d*B+d^2/2*(Z1+Z2)
' Wetted perimeter = B*d+(1/sin(atn(1/Z1))+l/sin(atn(1/Z2)))
Hydraulic Radius = R= Area/Wetted Perimeter
Velocity = 1.486/n*R^.667*s^.5
' Flow = Velocity*Area
n 0.016 for asphalt
s= longitudinal slope of gutter
'
'
DAVID EVANS AND ASSOCIATES
BOWSTR[NG METHOD (TEN YEAR STORM DESIGN) PROJECT: BRADLEY HEIGHTS
DETENTION BASIN DESIGN PROJECT NO: MAHA0005
BASIN: SG
' NUMBER OF DRYWELLS PROPOSED DESIGNER: DOUG BUSKO, P.E.
0 Single (type A) 1 Double (type B) DATE: 13 Jul-99
Total Area (calc.) (see H 1) 0.68
Time of Conc. (calc.) (see H 1) 7.77
Composite "C" (calc.) (see H 1) 0.40
Time of Conc. (min) 7.77
Area (Acres) 0.6794
C' Factor 0.40
Impervious Area (sq. ft.) 0
Volume Provided 208: 0 storm: 263
' Outflow (cfs) 1
Area * C" Factor 0.27
' #1 #2 #3 #4 #5 #6 #7
Time Time Intensity Q dev. V in V out Storage
Inc. Inc.
(min.) (sec.) (in./hr.) (cfs) (cu. ft.) (cu. ft.) (cu. ft.)
(#1 *60) (A*C*#3) (Outf.*#2) (#5-#6)
7.77 466.27 2.66 0.72 451 466.27 -15
5 300 3.18 0.86 347 300 47
10 600 2.24 0.61 462 600 -13 8
' 15 900 1.77 0.48 509 900 -391
20 1200 1.45 0.39 535 1200 -665
25 1500 1.21 0.33 545 1500 -955
30 1800 1.04 0.28 554 1800 -1246
35 2100 0.91 0.25 559 2100 -1541
40 2400 0.82 0.22 570 2400 - l 830
45 2700 0.74 0.20 575 2700 -2125
50 3000 0.68 0.18 584 3000 -2416
55 3300 0.64 0.17 602 3300 -2698
' 60 3600 0.61 0.17 623 3600 -2977
65 3900 0.60 0.16 662 3900 -3238
70 4200 0.58 0.16 687 4200 -3513
75 4500 0.56 0.15 709 4500 -3791
' 80 4800 0.53 0.14 714 4800 -4086
85 5100 0.52 0.14 743 5100 -4357
90 5400 0.50 0.14 755 5400 -4645
' 95 5700 0.49 0.13 780 5700 4920
100 6000 0.48 0.13 803 6000 -5197
DRAINAGE POND CALCULATIONS
Grassy swale'208' pond storage volume ,
= Impervious Area x.5 in./ 12 in./ft. = required: 0 cu. ft.
provided: 0 cu. ft. NO GOOD
DRYWELL REQUIREMENTS - 10 YEAR DESIGN STORM
Maximum storage by Bowstring = required: 47 cu. ft.
provided: 263 cu. ft. OK!
lYumber and type of drywells required = 0 SINGLE
1 DOUBLE
'
DAVID EVANS AND ASSOCIATES
' PROJECT: BRADLEY HEIGHTS DESIGNER: DOUG BUSKO, P.E.
PROJECT NO: MAHA0005 DATE: 13-Ju1-99
BASIN: SG
1 TIME OF CONCENTRATION (min) Surface Areas "C"
Tc (overland) Tc (gutter) Description (acres)
Ct = 0.15 L2 = 0 Grass, House, Road 0.6794 0.40
Z 1= 0 0.0000 0.00
L 1(A) = 180 Z2 = 0 0.0000 0.00
' N(A) = 0.4 B= 0 0.0000 0.00
S(A) = 0.01 n= 0 0.0000 0.00
s = 0 0.0000 0.00
' Tc (A) = 7.77 d= 0 0.0000 0.00
Total A Comp "C"
Lt(B) = 0 Tc (gu) = 0.00 0.68 0.40
N(B) = 0.016 Tc(A+B) = 7.77
S(B) = 0.008 Q=C*I*A= 0.72
Tc(tot.) = 7.77 Q(est.) = 0.00
Tc (B) = 0.0 Intensity = 2.66
A= 0
WP = #DIV/O!
R = #DIV/O!
' V = #DIV/O!
Tc (total) = Tc (overland) + Tc (gutter) Tc(gu) _ #DIV/O!
Tc (overland) = Ct*(L 1 *N/S^0.5)^0.6) Q(est) _ #DIV/O!
Ct=0.15
Ll = C,ength of Overland Flow Holding = 0.00
N= friction factor of overland flow (.4 for average grass cover)
S= average slope of overland flow
Tc (gutter) = Length (ft.)/Velocity (ft./sec.)/60
B= Bottom width of -utter or ditch
Z 1= inverse of cross slope one of ditch
Z2 = inverse of cross slope two of ditch
d= depth of flow in gutter (estimate, check estimate with Flow)
' Area = d*B+d^2/2*(Zl+Z2)
Wetted perimeter = B*d+(1 /sin(atn(1 /Z 1))+I/Sin(atn(1 /Z2)))
Hydraulic Radius = R= Area/Wetted Perimeter Velocity = 1.486/n*R^.667*s^.5
, Flow = Velocity*Area
n = 0.016 for asphalt
s= tongitudinal slope of gutter
'
DAVID EVANS AND ASSOCIATES
BOWSTRING METHOD (TEN YEAR STORM DESIGN) PROJECT: BRADLEY HEIGHTS
DETENTION BASIN DESIGN PROJECT NO: MAHA0005
BASIN: SH
, NUMBER OF DRYWELLS PROPOSED DESIGNER: DOUG BUSKO, P.E.
0 Single (type A) 1 Double (type B) DATE: 13 Jul 99
Total Area (calc.) (see H 1) 0.68
Time of Conc. (calc.) (see H 1) 8.88
Composite "C" (calc.) (see H 1) 0.40
Time of Conc. (min) 8.88
Area (Acres) 0.6794
C' Factor 0.40
Impervious Area (sq. ft.) p
Volume Provided 208: 0 storm: 263
Outflow (cfs) I
Area * C" Factor 0,27
#1 #2 #3 #4 #5 #6 #7
Time Time Intensity Q dev. V in V out Storage
Inc. . Inc.
(min.) (sec.) (in./hr.) (cfs) (cu. ft.) (cu. ft.) (cu. ft.)
(#1*60) (A*C*#;) (Outf.*#2) (#5-46)
' 8.88 533.07 2.45 0.67 476 533.07 -58
5 300 3.18 0.86 347 300 47
10 600 2.24 0.61 476 600 -124
' 15 900 1.77 0.48 520 900 -380
20 1200 1.45 0.39 544 1200 -656
25 1500 1.21 0.33 553 1500 -947
30 1800 1.04 0.28 560 1800 -1240
35 2100 0.91 0.25 564 2100 -1536
40 2400 0.82 0.22 575 2400 -1825
45 2700 0.74 0.20 579 2700 -2121
50 3000 0.68 0.18 588 3000 -2412
55 3300 0.64 0.17 605 3300 -2695
' 60 3600 0.61 0.17 . 627 3600 -2973
65 3900 0.60 0.16 665 3900 -3235
70 4200 0.58 0.16 691 4200 -3509 75 4500 0.56 0.15 712 4500 -3788
80 4800 0.53 4.14 717 4800 4083
85 5100 0.52 0.14 746 5100 -43 54
90 5400 0.50 0.14 758 5400 -4642
' 95 5700 0.49 0.13) 783 5700 -4917
100 6000 0.48 0.13 806 6000 -5194
DRAINAGE POND CALCULATIONS
Grassy swale'208' pond storage volume
= Impervious Area x.5 in./ 12 in./ft. = required: 0 cu. ft.
provided: 0 cu. ft. NO GOOD
DRYWELL REQUIREMENTS - 10 YEAR DESIGN STORM
Maximum storage by Bowstring = required: 47 cu. ft.
provided: 263 cu. ft. OK!
Number and type of drywells required = 0 SIIYCLE
1 DOUBLE
DAVID EVANS AND ASSOCIATES
' PROJECT: BRADLEY HEIGHTS DESIGNER: DOUG BUSKO, P.E.
PROJECT NO: MAHA0005 DATE: 13-Jui-99
BAS[N: SH
'
TIME OF CONCENTRATION (min) Surface Areas "C"
Tc (overland) Tc (gutter) Description (acres)
Ct = 0.15 L2 = 0 Grass, House, Road 0.6794 0.40
Z 1= 0 0.0000 0.00
L 1(A) = 225 Z2 = 0 0.0000 0.00
N(A) = 0.4 B= 0 0.0000 0.00
S(A) = 0.01 n= 0 0.0000 0.00
s = 0 0.0000 0.00
~ Tc (A) = 8.88 d= 0 0.0000 0.00
Total A Comp "C"
L 1(B) = 0 Tc (gu) = 0.00 0.68 0.40
N(B) = 0.016 Tc(A+B) = 8.88
S(B) = 0.008 Q=C*I*A= 0.67
Tc(tot.) = 8.88 Q(est.) = 0.00
Tc (B) = 0.0 Intensity = 2.45
A- 0
WP = #DIV/O!
R = #DIV/O!
V = #DIV/O!
Tc (total) = Tc (overland) + Tc (gutter) Tc(gu) _ #DIV/O!
Tc (overland) = Ct*(L1*N/S^0.5)^0.6) Q(est) _ #DIV/O!
Ct - 0.15
Ll = Length of Overland Flow Holding = 0.00
N= friction factor of overland flow (.4 for average grass cover)
S= average slope of overland flow
Tc (gutter) = Length (ft.)Nelocity (ft./sec.)/60
B= Bottom width of gutter or ditch
Z1 = inverse of cross slope one of ditch
Z2 = inverse of cross slope two of ditch
d= depth of flow in gutter (estimate, check estimate with Flow)
' Area = d*B+d^2/2*(Zl+Z2)
Wetted perimeter = B*d+( I/sin(atn(1 /Z 1))+1 /sin(atn(1 /Z2)))
Hydraulic Radius = R= Area/Wetted Perimeter
Velocity = 1.486/n*R^.667*s^.5
Flow = Velocity*Area
n = 0.016 for asphalt
s =longitudinal s(ope of gutter
'
'
,
'
PEAK FLOW CAi,CULATIONS (ROAD AREA ONLY)
I
Q= CiA
Assumes: C= 0.9, i= 3.18 in./hr.
Basin A, Acres Q, cfs
A 0.028 0.08
B 0.037 0.11
C 0.034 0.10
D 0.032 0.09
E 0.050 0.14
,
F 0.060 0.17
G 0.085 0.24
H 0.085 0.24
'
'
Drainage Report for Bradley Heights Subdivision ~
MAHAOOT/DRAINREP711DOC 07/14/99
'
' Worksheet
Worksheet for Triangular Channel
'
Project Description .
Project File s:lengrlmaha0005\basinf.fm2 '
Worksheet gutter
Flow Element Triangular Channel ~C5)~~
Method Manning's Formula
Solve For Channel Depth
' Input Data
Mannings Coefficient 0.013
Channel Slope 0.005800 fUft
Left Side Slope 12.350000 H: V
' Right Side Slope 0.167000 H: V
Discharge 0.17 cfs
Results
Depth 0.14 ft
' Flow Area 0.12 ft2
Wetted Perimeter 1.86 ft
Top Width 1.74 ft
' Critical Depth 0.14 ft
Critical Slope 0.006616 ft/ft
Velocity 1.41 ft/s
Velocity Head 0.03 ft
Specific Energy 0.17 ft
Froude Number 0.94
Flow is subcritical.
t
'
07/13/99 DAVID EVANS AND ASSOCIATES FlowMaster v5.08
11:25:27 AM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page 1 of 1
' -
OEPTH OF FLOW - y- FEET <W4L~5 /C D• / 7 cf's
.OI .02 .03 .04 .OS .06 .08 .10 .2 .3 .e .S .6 .T .8 .9 !.O
Li 1.0
~ ~ + fTl'~"T1 I~T ~ I + .e
4- -T- 4- .6
-L -rrt- ~
,
~ .s
T- - 1-
- ( J " j "r+-T ! 1 r j --L -1- ~ 4--
,
.
r ~
- ; J .
l-+-
,
.3
.2
oa
X%
L a
y o _ io 0 09
.oe C~
L 1 L ~ .06f~i.
, r ♦
os
~
.os' •
~ I ~ ~~I ~~'I _ T~
~ . ,
f I I ( I l' ( i i i I I I I' .02
t---~--~-1-
~
. ~ ~ I 1 ~ ~ I I ~ I I I I i ~ .oi '
I t ~ 1.0
( a) DISCHARGE PER FOOT OF
LENGTH OF CURB OPENING .6
INLETS WHEN INTERCEPTING ~ .s
100 % OF GUTTER FLOW - - - ~ - - - -t- -i
.a
~ - - - - - - - ~
Q
(b) PARTIAL INTERCEPTION ~•3 Qa
RATIO FOR INLETS OF - ~ -~---~---t--r---~--•-1-
LENGTH LESS THAN L. , j /~o / I ~ I I I I
, ~---F---~--~-~~.z
00,
001-
r ! ~ ~ I I ~.io
.OS .06 .08 .10 .2 .3 .4 .S .6 .8 1.0
. L/La
CAPACITY OF CURB OPENING INLETS
ON CONTINUOUS GRADE
6-39 FIGURE 16
,o 5
.
,z S
1.a . 2
b
,9 ' r
10 ~ u-. 1.5
r
:8 U.
9 Z
♦
:t r Z i
~ ~ ~ ♦ 1.0
I0i.
7.5 ~ h
~ T
t9
~ ti.o 4t ~,r Z
6•5 U.
W .7
i a
o
.s ~
w
0 .6
~S
2
♦ ?
W ,Z,s 2 " o .4
u3 0
Z
` 1 Z
U. ~
, Z Q.t*~~`''~
° a
0-0 4 .3
Z •3 Z.Qd G~s cr.
Z ~ -
06 Q •25
0 0 3
0 ZS 0 44 W ~f I7 ~~,~t
O
U. ci: F- ~
.
a
t9
= z.a a o
.
.2 ~ .02 p
~
Q d Q~ f
a ~ Q
Q cr.
u
2 Q1
L CURB
.1 '
~ N~„'~'•. ,,y_,~ 0.{
. ~ , N • r
i , ,~•r ' ~ C " gg10M lal
1.'~ LpCAI. OEFRE
R ~APACl TY O INTS
~
. ~ oM~~R pPH FJpT t-OW PO
~ N P ~NiNG
4 a .`--4 , ,.Z ~uRE 17
~
PueL ROA4S ~
gUaEaU wASH%NGTdN• .G
otviStoN iwo. 6_41
Appendix C
Site Photos
~en
. , , • Pi-ofessionals
Outstandingy Quality DAVID EVANS AND ASSOCIATES,
~ i
,
Looking west on Mission Avenue, along south plat boundary.
._~...,w
- ~ ' +
~z ~
' •ry -
~~~w• ,
~
•w
r ,
i
r ~ A
L
,
~ .Cra
1
_ Existing Edgerton Court cul de sac.
K/MAHA0005/PNOTO. dec
'
~ -
~ • ' ~ ~ . ~
' ~ ` # ' • . a '
. ,
~ ~ ~ d ~ ~
•r .
- !
S~ ~ ~ ~1 ~ ~ y • `l~ ~A~
~ , ~ ..k, ~
0,e
~ ♦
s~.~~~...
t
1-0
n
" r -
~ • ~ .
-
r r
Looking south on Center Road, toward Mission Avenue.
Bradley Heights is on the right side of the photo.
•
'
y ~
- ~'$..r~~~'f• ~ ,w.
~ ,i.%`► ~ - .
- ✓ _.-y
r r..
~
w
i
u
Northeast corner of intersection Mission Avenue aad Center Road.
°
K/MqHA0005/PHOTO.doc
'
'
'
~
i ~ ~ ~ ~ ~ . p> • _ _ r -
~ • ~ `~"'~,,,,i'~ •
_ •
• p11rt ~ r
. _ . . • ° M:': t ~ 1rY~
Y+~
Drywell on west side of Edgerton Court.
,
,
♦
i
~
' ` * ~ ~ ~ ~ ~ i ~ ~R.
e ~~t ~►r• ~ 4 ~~V _ ~ ~ , ~
,
Drywell on east side of Edgerton Court.
K/MAHA0005/PHOTO. doC
Appendix D
Po5t-De11eloped Bas1n Map
. DAVID EV'ARTS AND ASSOCIAI'E5,