HomeMy WebLinkAbout999700030 Drainage Reporto Plarmers
DEPT. OF COMMUNITY bEvELoP~,~ENT
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Po.po Ros. ources
1.59 Wyatt W'a...
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APPROVED BY
JEFFERSON COUNTY
DEP'~.
Attachment 1.c
MACLEARNSBERRY, INC.
CIVIL ENGINEERS -- LAND SURVEYORS -- PLANNERS
159 WYATT waY NE
BAINBRIDGE ISLAND. WA 98110
{206) 842.5514
STORM DRAINAGE REPORT
FOR
TEAL LAKE VILLAGE DIVISION II (PHASE 1)
I. Introduction'
Pope Resources is proposing to develop the single-family subdivision of Teal Lake Village
Division II, on the south side of Port Ludlow Bay. A Preliminary Plat has been approved by
Jefferson County and it is the intent of the Developer to conduct final platting and site
improvements in the Spring of 1996 in order to have lots available to the public by the Summer
of 1996.
II. Site Description:
The proposed plat of Teal Lake Village Division II lies, predominately, in the northeast-quarter
and the southeast-quarter of Section 21, Township 28 North, Range 1 East, W.M. It is bounded
on the north by the plats of Teal Lake Village Division I and Fairwood Village, on the west by
the preliminary plat of Springwood, and on the south and east by unplatted Pope Resources
lands.
The site straddles the Teal Lake Road and contains a total of 110.27 acres of land, 71.84 acres
of which lies east of the road in Phase 1, with the remaining 38.38 acres in Phase II, west of
the Teal Lake Road. Ground cover consists of small second growth, mixed coniferous and
deciduous cover.
Phase 1 lies, predominately along a north-south running ridge. The land falls away to the west,
toward the Teal Lake Road at slopes of eight to ten percent. The more irregular terrain to the
east falls toward a ravine at slopes upwards of eight to twenty percent. The gently sloping
rideeline rises from an elevation of 310', at the project entrance on the Teal Lake Road, to 480',
at the flat ridgetop.some 2600 feet to the southeast.
According to the SCS Soil Survey of Jefferson County the soil type covering the site is
Cassolary, which falls in Hydrologic Group C.
III. Project Description:
The proposal consists of a 36 lot subdivision with .the main access off the Teal Lake Road and
running along the center of the ridge, and culminating in a mrn around at the top of the ridge,
some 2750 feet to the southeast. The southerly extension Of Crestview Drive will connect to
Teal Lake Village Div. I approximately 300 feet in from the entrance and a 450 foot long cul-
de-sac extends from the main road at approximately station 10+00.
When completed, the 36 lots will cover approximately 57 % of the site and range in size from
0.8 acre to 1.6 acres.
IV. Existing Drainage Conditions:
A. The Drainage Basin:
The aforementioned ridge divides storm water runoff from Phase I. Storm water' runoff from
the east side of the ridge drains to the north-flowing ravine, which runs along the easterly
boundary of the plat. Runoff from the west side of the ridge is further divided. The southerly
portion of the runoff from the west side of the ridge flows to the Teal Lake Road and thence
northwesterly in the roadside ditch to the creek which runs north, through the Port Ludlow Golf
Course. The northerly portion of the sub-basin flows, naturally, into the ravine, which runs,
northerly, along the east side of Teal Lake Village Division I.
B. Site Drainage:
Due to the lay of the land, the large amount of natural open space, the fact the that most of the
proposed lots lie along the ridgetop, and size of the lots, most of which will remain in their
natural state, the predominance of the project site will not be affected by land clearing activities.
Most of the site will continue to drain as in its undeveloped condition. Therefore, only that
portion of the site, which will actually be disturbed, will be addressed in the drainage analysis.
V. Downstream Drainage Conditions:
The primary stream flowing into the Ludlow Bay drainage basin is Ludlow Creek, which drains
the bulk of the Chimicum Valley and culminates at the head of Port Ludlow Bay. The north-
flowing stream in the valley in which the Port Ludlow Golf Course lies, and a series of steep
ravines, drain into the south side of Port Ludlow Bay, east of Ludlow Creek. All of these
drainage sub-basins flow through large culverts, under the Port Ludlow - Paradise Bay Road and
on into the bay through well defined channels.
VI. Proposed Drainage Improvements:
A. OFF-SITE, UPSTREAM
Off-site, upstream, draina, ge all flows in from south along the aforementioned easterly ravine and
the Teal Lake Road ditches and bypasses the project site. Accordingly, this runoff does not
affect the project and will not be addressed further.
B. ON-SITE DRAINAGE
Jefferson County (by virtue of it's reference to the DOE Manual), requires detention of the 2-
year, 10-year and 100-year, 24-hour storm events, with a release rate equal to one-half of the
2-year storm discharge quantity, under undeveloped conditions. In addition, the DOE Manual
requires storm water quality control in the form biofiltrafion, or storage capacity for the 6-mos,
24-hour storm event (0.64 of the 2-year storm event).
It is anticipated that the 36, approximately one-acre, lots in the project will be improved to only
a distance of about 100-feet back from the street. For purposes of this report it will be assumed
that the entire width of each lot will be cleared (actually clearing will probably not be this
extensive). This being the case, total lot clearing will amount to 15.69 acres, or 0.436 acre per
lot. Furthermore, 4.72 acres of road right-of-way will be cleared, for a total of 20.41 acres to
be cleared out of the total 71.89 acres in Phase 1.
Of the 0.44 acre of cleared area per lot, it is anticipated that there will be 4000 square feet, or
0.09 acre of impervious area in the form of buildings, driveways, patios and side walks, this
leaves 0.36 acre per lot for lawn and landscaping.
The developed site will divide into two sub-basins, each one draining to a separate detention
facility. For purposes of this report these sub-basins will be described as Sub-basin A and Sub-
basin B. Their characteristics are described as follows:
Sub-basin A:
Description: 31 lots consisting of Lots 1 th.rough 9 and Lots 15 through 36.
Of these lots, drainage from the building sites on Lots 6, 8 and 9, 23 through 34 cannot be
intercepted, either directly or indirectly, by the roadside ditch system and will have to have
individual infiltration systems designed and constructed at the time of individual house
construction on the lots. Therefore, drainage from 28 building sites will be directed to the Sub-
basin A detention facility:
0.435 acres/lot x 16 lots = 6.96 acres draining to detention facilities.
0.09 acre/lot x 16 lots = 1.44 acres combined lot impervious area.
6.96 acres - 1.44 acres = 5.52 acres combined lot pervious area (Developed Conditions).
Road System:
There are 4.34 acres of road right-of-way in Sub-basin A. of which 1.92
act:es will be paved.
Right-of-way area in pervious area = 4.34 - 1.92 = 2.42 acres.
Total impervious area = 1.44 acres (lots) + 1.92 acres (roads) = 3.36 acres
Total pervious area in lawns landscaping = 5.52 acres + 2.42 acres = 7.94 acres
Total natural pervious area (woods) = 4.31 acres.
Total existing pervious area within this analysis = 6.96 acres + 4.34 acres + 4.31 acres =
15.61 acres.
(1)
Time of Concentration Worksheets were prepared for both existing and developed site
conditions (see Appendix A-1 and A-2).
(2)
Four hydrographs were created for: the 2-year, 24-hour storm event and the 100-year,
24-hour storm event, under existing conditions, and the 2-year, 24-hour storm event and
the 100-year, 24-hour storm event, under developed conditions (see Appendix A-3 and
A-4).
(3)
The hydrographs for the 2-year, 24-hour storm event and the 100-year, 24-hour storm
event, under developed conditions, using one-half the release rate under existing
conditions (0.16 cfs) for the 2-year event and the full release rate under existing
conditions for the 100-year event (see Appendix A-5 and A-6) were used to size a
detention pond for the sub-basin. The resultant pond was determined to be 31,378 cubic
feet in volume. The top area of the resultant pond is 13,886.9 square feet, resulting in
a rectan~lar pond 84 feet wide by 167 feet long. The routing data was filed for
reference (A100.Det).
(4)
Finally, the above mentioned hydrographs for the 2-year and 100-year, 24 hour storm
events (for developed conditions) were routed through the design pond using the
Reservoir Routing Inflow/Outflow Routine to verify the adequacy of the pond volume.
The peak storage calculated out at 31,370 cubic feet.
Sub-basin B:
Description: 5 lots consisting of Lots 11 through 14.
Of these lots drainage from the building sites on Lots 10 through 13 cannot be intercepted, either
directly or indirectly, by the roadside ditch system and will have to have individual infiltration
systems designed and constructed at the time of individual house construction on the lots.
Therefore, drainage from one building site will be directed to the Sub-basin A detention facility:
0.436 acres/lot x 1 lots = 0.436 acres draining to detention facilities.
0.09 acre/lot x 1 lots = 0.09 acres combined lot impervious area.
0.436 acres - 0.09 acres = 0.346 acres combined lot pervious area (Dev.)
Road System:
There is 0.38 acre of road right-of-way in Sub-basin A. of which 0.24
acre will be paved.
Right-of-way area in lawn = 0.38 - 0.24 = 0.14 acres.
Total impervious area = 0.09 acres (lots) + 0.24 acres (roads) = 0.33 acres
Total pervious area in lawns landscaping = 0.346 acres + 0.14 acres = 0.49 acres
Total unimproved area draining to detention = 0.49 acres
Total existing pervious area within this analysis = 0.38 acres + 0.49 acres + 0.49 acres =
1.36 acres.
(1)
(2)
(3)
Time of Concentration Worksheets were prepared for both existing and developed site
conditions (see Appendix B-1 and B-2).
Four hydrographs were created for: the 2-year, 24-hour storm event and the 100-year,
24.-hour storm event, under existing conditions, and the 2-year, 24-hour storm event and
the 100-year, 24-hour storm event, under developed conditions (see Appendix B-3
through B-5).
The hydrographs for the 2-year, 24-hour storm event and the 100-year, 24-hour storm
event, under developed conditions, using one-half the release rate under existing
conditions (0.015 cfs) for the 2-year event and the full release rate under existing
conditions for the 100-year event (see Appendix B-6 and B-7) were used to size a
detention pond for the sub-basin for comparative
purposes. The resultant pond was determined to be 2,838 cubic feet in volume. The top
area of the resultant pond is 2,082 square feet, resulting in a recta, ngular pond 33 feet
563
(4)
wide by 66 feet long.
Finally, the above mentioned hydrographs for the 2-year and 100-year, 24 hour storm
events (for developed conditions) were used to determine the required length of a four
foot diameter detention pipe. The required pipe length was determined to be 225.4 lineal
feet, with a storage capacity of 2829 cubic feet (see Appendix B-8 and B-9).
OFF-DRAINAGE DOWNSTREAM
Water from the detention pond will discharge into the roadside ditch on the Teal Lake road;
thence down the Teal Lake road ditch to the Highland Drive intersection, where it will flow
westerly, along the ditch adjacent to Highland Drive and into the main north-flowing stream,
which drains the Port Ludlow Golf Course.
VII. Conclusion
Rules in the current edition of the State Department of Ecology's Storm Water Technical
Manual (hereinafter called the Manual) require that, for a project of this magnitude, a Storm
Water Site Plan be prepared and implemented. This site plan will have two elements, an
Erosion and Sediment Control Plan for temporary control of pollution generated during
construction, and a Permanent Storm Water Quality Control Plan for control of pollution from
storm water after construction is completed. The Manual lists eleven Best Management
Practices which pertain to this project. These requirements and the descriptions their elements
are listed in Appendix C.
/
PE
EXPIRES
VASHINGTOiN SHEET NUMBER 55
------...--- : (Joins sheet 52
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KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL
'ABLE 3.5.2B SCS WESTE~ WASHINGTON RUNOFF CURVE NUMBERS
SCS WESTERN WASHINGTON RUNOFF CURVE NUMBERS (Published by SCS in 1982)
Runoff curve numbers for selected agricultural, suburban and urban land use for Type lA
rainfall distribution, 24-hour storm duration.
LAND USE DESCRIPTION
Cultivated land(l): winter condition 86 91 94 95
Mountain open areas: Iow growing brush and grasslands 74 82 89 92
Meadow or pasture: 65 78 85 89
Wood or forest land: undisturbed 42 64 76 81
Wood or forest land: young second growth or brush 55 72 81 86
Orchard: with cover crop 81 88 92 94
Open spaces, lawns, parks, golf courses, cemeteries,
landscaping.
good condition: grass cover on 75%
or more of the area
fair condition: grass c6ver on 50%
to 75% of the area
Gravel roads and parking lots
Dirt roads and parking lots
Impervious surfaces, pavement, roofs, etc.
Open water bodies: lakes, wetlands, ponds, etc.
Single Family Residential (2)
Dwelling Unit/Gross Acre % Impervious (3)
1.0 DU/GA 15
1.5 DU/GA 2O
CURVE NUMBERS BY
HYDROLOGIC SOIL GROUP
A B C D
68 8O 86 90
77 85 90 92
76 85 89 91
72 82 87 89
100 100 100 100
Separate curve number
shall be selected
2.0 DU/GA 25
2.5 DU/GA 30
3.0 DU/GA 34
3.5 DU/GA 38
4.0 DU/GA 42
4.5 DU/GA 46
5.0 DU/GA 48
5.5 DU/GA 50
6.0 DU/GA 52
6.5 DU/GA 54
7.0 DU/GA 56
Planned unit developments,
condominiums, apartments,
commercial business and
industrial areas.
% impervious
must be computed
for pervious and
impervious portion
of the site or basin
(1) For a more detailed description of agricultural land use curve numbers refer to National Engineering
Handbook, Section 4, Hydrology, Chapter 9, August 1972.
(2) Assumes roof and driveway runoff is directed into street/storm system.
(3) The remaining pervious areas (lawn) are considered to be in good condition for these curve numbers.
3.5.2-3 ltO0
124 123 122
FRIDAY HARI OR
'PORT STA
40
4~
50
15
124
FRIDAY HARB
\
!
17.5
123
PORT STANLEY
122
i¢.,,.
7~,
7O
7
5~
5~
45
ABERDEEN-40.:
-~. ,
,
..
i0-?.~,AR 2?-- '0iJ,q PRECi?iT,a'}"i!}N
TACOMA
I
I
X\ '".,..
,' \
2
/
AMS
~.~ ,,
..{'- r" r" ~ ! ,
.,
..",~ ,'
124 123 122
45
FRIDAY HARBOR
PO RT STANI
9C~
1
90
O0
COMA
ETT
' ABE~
55
55
iO0-YEAR
24-HOUR PRECIPtTATION
MacLEARNSBERRY, INC.
159 Wyatt Way NE
Bainbridge Island, WA
(206) 842-5514
98110
PROJECT:
JOB NO.:
DATE:
Teal Lake Village Div.
95034
o /1'o/96
II
TIME OF CONCENTRATION WORKSHEET
BASIN #
P2=
A(exist)
1.5
SHEETFLOW
TYPE
Woods
?
?
LENGTH
300
?
?
SLOPE
0.0567
.
?
SHALLOW FLOW: LENGTH SLOPE
Woods 150 0.1233
· . .
· .
· .
· .
INTERMIT: LENGTH SLOPE
Road Ditch 1400 0.0768
? ? ?
.
· ,
MacLEARNSBERRY, INC. PROJECT:
159 Wyatt Way NE JOB NO.:
Bainbridge Island, WA 98110 DATE:
(206) 842-5514
N Tc
O.8 86.68
? 0.00
? 0.00
K V Tc
3 1.05 2.37
? 0.00 0.00
? 0.00 0.00
? 0.00 0.00
? 0.00 0.00
? 0.00 0.00
K V Tc
20 5.54 4.21
? 0.00 0.00
? 0.00 0.00
? 0.00 0.00
TOTAL Tc= 93.27
Teal Lake Village Div. II
95034
01/10/96
TIME OF CONCENTRATION WORKSHEET
BAS IN #
P2=
A(exist)
1.5
SHEETFLOW
TYPE
Woods
LENGTH SLOPE
300 0.0567
· .
· .
N Tc
0.8 86.68
? 0.00
? 0.00
SHALLOW FLOW: LENGTH SLOPE K
Woods 150 0.1233 3
·
.
·
.
~ Tc
1.05 2.37
0.00 0.00
0.00 0.00
0.00 0.00
0.00 0.00
MacLEARNSBERRY, INC.
159 Wyatt Way NE
Bainbridge Island, WA
(206) 842-5514
98110
PROJECT:
JOB NO.:
DATE:
Teal Lake Village Div.
95034
01/10/96
II
TIME OF CONCENTRATION WORKSHEET
BAS IN #
P2=
A (der)
1 5
SHEETFLOW
TYPE
Lawn
·
.
LENGTH
50
?
·
SLOPE
0.01
?
·
N
0
SHALLOW FLOW: LENGTH SLOPE K
Lawn 50 0.01
? ? ? ?
? ? ? ?
? ? ? ?
· · .
INTERMIT: LENGTH SLOPE
Road Ditch 800 0.0375
Road Ditch 800 0.0163
Road Ditch 800 0.169
· ·
K
.15
11
17
17
17
V
1.10
0.00
0.00
0.00
0.00
0.00
V
3.29
2.17
6.99
0.00
TOTAL Tc=
Tc
10.85
Tc
0.76
Tc
4.05
6.14
1.91
23 .70
MacLEARNSBERRY, INC.
159 Wyatt Way NE
Bainbridge Island, WA
(206) 842-'5514
98110
PROJECT:
JOB NO.:
DATE:
Teal Lake Village Div.
95034
Ol/lO/96
II
TIME OF CONCENTRATION WORKSHEET
BAS IN #
P2=
A(dev)
1.5
SHEETFLOW
TYPE
Lawn
.
.
LENGTH
5O
·
O '
SHALLOW FLOW: LENGTH
Lawn 50
.
SLOPE
0.01
.
·
N
0.15
SLOPE
0
K
.01 11
563
V
1.10
0.00
0.00
0.00
Tc
10.85
Tc
0.76
DATA PRINT-OUT:
AREA(ACRES) PERVIOUS IMPERVIOUS TC(MINUTES)
A CN A CN
15.6 15.6 81.0 .0 98.0 93.3
PEAK-Q(CFS) T-PEAK(H~S) VOS(CU-FT)
r-3~2- .~./~ 12.50 17666
ENTER [d:l[path]~ilename[.ext] FOR STORAGE OF CCHPU:.' D HYDROGRAPH:
b: a2ex.hyd
S P T,:C. ] FY
L00,24,
.~'~
· C - CONTINUE, N - N~STO~L}d, P - PRINT, S - STOP
3.2
· ~************ S.C.S. TYPE-lA D[S'~RIBL~'I'[ON
· * 100-YEAR 24-}](.)UR STORM **** 3.20" TOTAL PRECIP. ******'~*
ENTER: A(PERV), CN(PERV), A(]MPERV),
15.61,81,0,98,93,39
m~
CN(]MPERV), TC FOR BASIN NO. 1
~A'?A PRINT-OUT:
AREA(ACRES) PERVlOUS ]MP~:RV I OUS
A CN A CN
15.6 15.6 81.0 .0 98.0
TC<MINUTES)
93.3
PEAK Q (C::'S)' '~' -PEAK(HRS) VOL (CU-F'F)
2.05 8.50 82189
~ '['FER Ii,t:][path]~ilename[.~xt] ~'O[{ STORAGE OF COMPUTED HYDROGRAPH:
b:al00ex.hyd
S.C.S. TYP':,.. IA DISTRIBUTION ********************
24-HOUR STC~:I~, **** 1.50" TO'l'~%i. '~'RECiP. *********
· '~i~'. A(PERV), CN(PERV),
,.~ . 25,84,3.36,9:3,9.3.7
A(IM]:'E]~V), CN(IMPERV), TC FOR BASIN NO. 1
DATA PRINT-OUT'
AREA(AC~::S) PERVIOUS
A CN
15.6 12.3 84.0
IMPERVIOUS TC (MINUTES)
A CN
3.4 98.0 2~.7
: ' :,:A K.7. Q (__CF_S_) .... T-PEAK( ~{L~S ) VOL( CU- J:':L'
1.47 7.83 33877
~'NTER [d'][gath]~'i 1.~.name[.ext] FOR STORAGE OF CO~:[L:UT'.:~:. :i.'(~)ROGRAPH:
b: a2dev, hyd
SPECIFY: C - CC)N'I']NUE, N - NEWSTORM, P - PRINT, S - STOP
100,24,3.2
***************-***** S.C.S. TYPE-lA DI.~'~';~r. SUTION
********* 100--YEAR 24-HOUR STORM **** 3.20" TO'L'~,. PRECIP. *********
ENTER' A(PERV),
.L2,25
84,3.26,98,23.7
CN(PERV), A(t'-.'.:~ERV), CN(IMPERV), TC 5'0){ BASIN NO. 1
b,,£A PR IN'J'
AR E;., ( A CR.~: .:: )
15.5
PEI<v J OUS IMPERVIOUS TC(MINUTES)
A CN A CN
12.3 84.0 3.3 98.0 23.7
PEAK-Q(Cb'S) T-PEAK(HR$) VO~ (CU-FT)
5.81 7.83 109795
ENTER [d'][.ga~.'..,]l'i. Lename!i.ex~..] ::'OR STORAGI~ OF '.':4.1?UTED HYDROGRAPH:
·
b'al00de;'.~,~ ,
SPEc'~'Y: C - CONTIN!iI='., N - NEWSTORM, P - PRINT, $ - S'1'(,~
~
ENTER '
3
POND SIDE SLOPE (HORIZ. COMPONENT)
ENTER: EFFECTIVE S'3'ORAG? DEPTH(ft) BEFORE oVERFLOW
3
ENTER [d:][path]f]]ename[.ext]
b:a100dev.hyd
PR/MARY DESIGN INFLOW PEAK =
OF PRIMARY
5.81 CFS
DESIGN
INFLOW HYDROGRAPH:
EN,':~,R ?~{!'MARY DESIGN RELEASE RATE(cfs):
2.05
ENTER NUMB;':~ OF INFLOW HYDROGRAPHS TO BE TESTED F~' PERFORMANCE
1
ENTER [d: ][path]f~lename[ .ext]
b:a2dev.hyd
ENTER TARGET RE!.EASE RATE(c~$):
0.16
OF HYDROGRAPH 1:
ENTER: NUMBER OF OK]FICES,
~,3,18
RISER-HEAD(~t),
RI SER-~DIAMETER
RISER OVERFLOW DEPTH FOR PRIMARY PEAK INFLOW = .54 FT
$~EC[FY ITERATION DISPLAY: Y - YES, N - NO
( 5 MA'~< '[MUE ):
SPECIFY: R - REVIEW/]<E'....-'.[~;~.~ INPUT, C - CONTINUE
c
INITIAL STORAGE VAI.UE FOR ITERATION PURPOSES: 346] 4 CU-FT
BOTTOM ORIFICE:
ENTER Q-MAX(cf s)
BOTTOM ORIFICE: ENT~.:~< Q-MAX(c~s)
0.18
DIA.= 1.96 INCHE~;
TOP ORIFICE: ~]NTt~.R HEIGHT(~t)
2.5
,~8 INCHES
DIA. = 9
PERFORMANCE: I NFLO%~; TARGET-OUTFLOW
DF, SIGN HYD: 5.81 2.05
TEST HYD 1: 1.47 .16
ACTUAL -OUTFLOW PK- STAGE STORAGE
2.04 3.00 3[378
.16 2.48 25120
:SPECIFY: D - DOCUMENT, R - R. EVISE,
d
P~RFORMANCF.: l NFI..OW TARGET- OU '.:' }.' i, OW
]SI~]N HY0: 5.81 2.05
TEST }IY)) 1: 1. 47 .16
A - ADJUST ORIF,
E - ENLARGE,. S - STOP
.,,
ACTUAL -OUT}"] .,~ :'~ PK- STAGE STORAGE
2.04 3.00 31378
· 16 2.48 25120
563186
R I .qER-]] EAD POND-BOTTOM-AREA
3r00 F't' "8591'8 SQ-.~.~t,
'.'oP-. ;.;< ~::A (@1 'F.B. )
1.3886.9 SQ
STOR-DEPTH
3.'00"PT-
OR.~ F I CE RESTRI CTOR ·
BOTTOM ORIl-' ICE:
TOP ORIFICE:
D I A ( i[ NCHES ) HT ( FEET ) Q-MAX ( CFS )
1.96 .00 .180
9.88 2.50 1.870
ROUTING DA'CA:
STAGE (FT) D I SCH,~ :-~'. ,.(CFS)
.00 .00
.3O .06
.60 .08
· 90 .10
1.20 .11
1.50 .13
1.80 .t4
2.10 .15
2.40 .t6
2.50 .16
2.70 1..35
3.00 2.05
3.10 2.69
3.20 3.71
3.30 4.95
3.40 6.40
3.50 8.OO
STORAGE ( CU-FT )
.0
2631.0
5370.0
8219.2
11180.3
14255.5
17446.5
20755.3
24184.0
25353.8
27734.4
31408.4
3).660.9
33927.4
:35208.1
36502.9
3781]..9
PERM-AREA(SQ-FT)
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
.0
AVERAGE VERTICAL PE;{~4EA~'. ? ~,TTY'
· 0 }4 ii NUTES/INCH
FILE, N - NEWJOB, P - ?l.'~,71't' I~F/OF,
R - REVISE, S - STOP
EN'PER [d:][path]fJ]ename[.ext] FOR STORAGE OF ROUTIN,,; ~. :.TA'
SPECIFY: F - FILE, N - NEWJOB, P - PRINT IF/OF, R - REVISE,
STORAGE-VoLu~
8" 'CU
S - STOP
ROUTING INVI,~°)W/OUTFLOW ROUTINE
· ~'~',:~'i.,.Y [d:][p~t,.h]Ei. lename[.extl
b:al00 ,det
DISPLAY ROUTING DATA (3 or N)?
¥
ROUTING DATA
R~-~UT.I NG DATA:
STAC.:i,: ( FT ) DISCHARGE (CFS)
.00 .00
.30 .06 2
.60 .08 5
.90 .10 8
1.20 .11 ~1.
1.50 .13 14
1,80 .14 17
2.10 .15 20
2.40 .1.6 24
2.50 ,16 25
2 . ';0 l . ')5 27
3.00 2.05 3]
3.10 2.69 32
3.20 3.71 33
3.30 4.95 ').5
3.40 6.40 36
3.50 8.00 3';
3.60 9.56 39
F. ( ,~-'. ~--FT )
,0
631.0
370.0
219.2
LB0.3
255.5
446.5
755.3
184.0
353.8
734.4
408.4
660.9
927.4
).08.1
502.9
8L1.9
135.3
PERM-AREA(SQ-FT)
,0
.0
.0
,0
.0
.0
.0
.0
,0
.0
.0
.0
.0
.0
,0
.0
.0
.0
PERM*~(A'?E: .0 MINUTES/INCH
ENTER [d:][path.]fJ'lenam:~.[.exL.] Cf' COMF'UTED HYDROGRAPH:
b: al".:0dev.
l ~:'.'~LOW/OUTFLOW ANAl,Y,~: ~ ,~;:
PEAK-]N; .... ."'CFTC)
5.81
PEAK-OUTFLOW ( {'.~'S )
2.04
OUTFLOW-V';!.:'CU-FT)
107043
INIT)A)--~;'.~';' ;E(F'I:) TIME-OF-PEA)< F:~':S)
,00 9.50
PEAK- STAGE- ELEV ( FT )
:~. O0
PEAK STORAGE: 313'/(°) CU-F'.
' F L let~ame[ ~xt ] ,'()R STORAGE OF COl~,~.~,,'~'~,:0 HYDROGRAPH:
ENTER Id'
5631.88
RESERVOIR ROUTING INFLOW/OUTFLOW ROUTINE
SIFY [d: ] [path]fi lename[.ext] OF ROUTING DATA
^.,, 100. DET
DISPLAY ROUI:ING DATA (Y or N)?
ROUTING DATA:
STAGE(FT) DISCHARGE(CFS) STORAGE(CU-FT) PERM-AREA(SQ-FT)
.00 .00 .0 .0
.30 .06 2621.0 .0
.60 .08 5370.0 .0
.go .10 8219.2 .0
1.20 .11 11180.3 .0
1.50 .13 14255.5 .0
1,80 .14 17446.5 .0
2.10 .15 20755.3 .0
2.40 .16 24184.0 .0
2.50 .16 25353.8 .0
2.70 1.35 27734.4 .0
3.00 2.05 31408.4 .0
3.10 2,6g 32660,g .0
3.20 3.71 33927,4 .0
3.30 4.g5 35208.1 .0
3.40 6.40 36502.9 .0
3.50 8.00 37811.9 .0
3.60 9.56 39135.3 .0
AVERAGE PERM-RATE: .0 MINUTES/INCH
ENTER [d:][path]filename[.ext] OF COMPUTED HYDROGRAPH:
A: ABBEV. HYD
INFLOW/OUTFLOW ANALYSIS:
PEAK-INFLOW(CFS)
1.47
PEAK-OUTFLOW(CFS)
.16
OUTFLOW-VOL (CU-FT)
31847
INITIAL-STAGE(FT) TIME-OF-PEAK(HRS)
.00 24.33
PEAK-STAGE-EL EV (FT)
2.48
PEAK STORAGE: 25120 CU-FT
ENTER [d:][path]filename[.ext] FOR STORAGE OF COMPUTED HYDROGRAPH:
^C
C:\HYD>
563
.{acLEARNSBERRY, INC.
159 Wyatt Way NE
Bainbridge Island, WA
(206) 842-5514
98110
PROJECT:
JOB NO.:
DATE:
Teal Lake Village Div.
95034
01/ 0/96
II
TIME OF CONCENTRATION WORKSHEET
BAS IN #
P2=
B ( exist )
1.5
SHEETFLOW
TYPE
Woods
?
?
LENGTH
300
,
?
SLOPE
0.1389
?
?
SHALLOW FLOW: LENGTH SLOPE
Woods 250 0.08
· · ·
. ·
N
0.8
·
·
K
11
·
·
.
V
3.11
0.00
0.00
0.00
0.00
0.00
INTERMIT: LENGTH SLOPE K V
~ ? ? ~ 0
? ? ? ~ 0
? ~ ? ? 0
? ? ? ? 0
TOTAL
.00
.00
.00
.00
TC=
TC
60.57
Tc
1.34
Tc
61.91
563
~acLEARNSBERRY, INC.
159 Wyatt Way NE
Bainbridge Island, WA
(206) 842-5514
98110
PROJECT:
JOB NO.:
DATE:
Teal Lake Village Div.
95034
01/10/96
II
TIME OF CONCENTRATION WORKSHEET
BASIN #
P2=
B (der)
1.5
SHEETFLOW
TYPE
Lawn
?
,
LENGTH
180
?
?
SHALLOW FLOW: LENGTH
.
· ·
· ·
?
INTERMIT: LENGTH
Road Ditch 250
· *
· ·
SLOPE
0.1389
?
?
SLOPE
.
·
·
·
K
SLOPE K
0.08
· ·
·
.15
17
V
0.00
0.00
0.00
0.00
0.00
0.00
V
4.81
0.00
0.00
0.00
TOTAL Tc=
Tc
10.55
Tc
Tc
0.87
11.42
563 191
ENTER:
2,24,1.5
************************
:~*~****** 2-YEAR
TYPE-iA RAINFALL DISTRIBUTION
FREQ(YEA~{), OURATICN(HO~'fR), PRECIP(INCHES)
..
S.C.S. TYP'.'-LA., DISTRIBUTION ******************.**..
24-HOUR STORM **** 1.50" TOTAL PRECIP. *********
ENTER' A(PERV), CN(PERV), A(IMPERV), CN(IMPERV), TC FOR BASIN NO.
1.36,81,0,9:{, 6l. 91
DATA PRINT-OUT:
AREA ( ACRES ) PEI~V I OUS
t...4 81.0
..
'\
..'
PEAK-Q( C]?S ) '1: ' P~AK(~IRS )
~ .-03- a. ~t~" /2[2.50
~TER [d:][,at¢]-~.l.,,aame[.ext]
b:b2"ox h~d "
IMPER¥ IOUS TC (MINU']'E:.
A CN
.0 98.0 61.9
VOl', (CO-PT)
1544
STORAGE OF COMPUTED [{YDR'
SPECIFY' C - CONTINUE, N - NEWSTOR~4, P - PRINT, S - STOP
S.C.S. TYPE-iA RAINFALL DISTRIBUTION
EN'~'ER: FREQ(YEAR), DURATION(HOUR), PREC: :?(~'NCHES)
2,10,2
*******'*'-'<***'~'~'~'**** S.C.S. 'I:YPE-1A DISTRIBUTION ***:" ": ~ ~***********
********* 2-YEAR 10-HOUR STORM **** 2.00" TO'F2. PREC[?. *;~'~:-':' ~'**'~-
ENTER' A(PERV), CN(PER¥), A(IM]'ERV), CN(IMPERV), TC FOR B.-'~.4IN NO. 1
!. 36, :~f,0,98,2
DA'.vA PRINT-OUT:
AREA(ACRES) PERVIOUS 1M ~'ERV .1 (~US TC(MINUTES)
A CN A CN
1.4 1.4 86.5 .0 98.7 2.0
PEAK-Q(CFS) T-PEAK(HRS) VOL(CU-FT) · 63 3.08 4136
ENTER ~.,t' ][L~alsh]~_lename[.extl
-'b' bl0ex.hyd
STORAGE OF
COMPUTED HYDROGRAPH:
5fi3 ,.,.,.-192
S.C.S. TYPE-iA RAINFAI.I. DIS'£;{IBUT1ON
~::;~'":']R: FREQ(YEAR), 5URA°,.'£~[([{OUR),
100,24,3.2
~m---- mmmmmmmmmmmmmmmmmmmmmmmwmmm__mmmmmmm
***********~***~* S.C.S. TYP~-iA DISTRIBUTION
~****** 100-YEAR 24-HOUR STORM **** 3.20"
.
ENTER: A(PERV), CN(PE:~V), A(IMPERV),
1:}.36,81,0,98,61.9.'1.
TOTAL PRECIP. *********
CN(1MPERV), TC FOR BASIN NO. 1
DATA ~':~[NT-OUT:
AREA(ACRES) PERVIOUS IMPERV]OUS
A CN A CN
1.4 1.4 81.0 .0 98.0
PEAK-Q( C~~J )' 't' - .P :ZAK ( HRS )
i .22 8.00
ENT:CR [d: ][~at'h]eil~.name[.ext]
b].00ex'.~hYd
V()L (CO-FT)
7181
FOR
.'
UTES)
6]..9
STORA(I:{ OF COMPUTED HYDROGRAPH:
SPECIFY: C - CONTINUE, N - NEWSTORIM, P - PRINT, S - STOP
1
S.C.S. TYPE-iA RATNFALL DISTR.[BUTION
.'~NTER' ['~REQ(YEAR), DURATI(DN(HOU~), PREC[P(:i~CI{ES)
2,24,1.5
'********~**e***** S.C.S. TY:~'~
...-lA DISTRIBUTION ***********************
********* 2-YEAR 24-HOUR STORM **** 1.50" TOTAL PR~.:c:~P. *********
ENTER: A(PERV), CN(?ERV),
L. 03 , 86,0 . 33988,11 . 42
A(IMPERV), CN(IMPERV), TC FOR BA.~N NC.. 1
DATA PRINT-OUT:
· .
AREA (ACREF;) PERV ] OU $
A CN
1.4 1.0 86.0
1.~PERV IOUS TC(MINUTES)
A CN
.3 98.0 1]..4
PEAK-Q(CFS) T-PEAK(HRS) ~;~),'.(CO-FT)
.20 7.83 3369
][path] F.L[ename[.ext] FOR
/b: b2dev, hyd
563
S. C. 'S.
~.i ~ ' [' E ~{ '
10,24,2
TYPE-lA RAINh'ALL DISTRIBUTI¢)~
FR:':Q(Y:~.A[{), DURAT£ON(HOUR), PRECIP([N,;HES)
**********~****~* S.C.$. TY~:~-LA DISTRIBUTION *~***************
'****** 10-YEAR 24-HOUR STORM **** 2.00" TOTAl. PRECIP. *********
ENTER: A(PERV), CN(PERV), A(IMPERV), CN(IMPERV), TC FO~ ~%ASIN NO. 1
I.. 03,86,0 · 33 , 98 , 11 . 42
DATA PRINT-OUT:
AREA(ACRES) PERVIOUS IMPERVIOUS
A CN A CN
1.4 1.0 86.0 .3 98.0
TC( ZNO?ES)
11.4
PEAK-Q(CFS) '[' · :.':<AK(HRS) VO~ (CU-FT)
.33 7.83 5294
I..~l Id: ] [path If]. I. e~ame[ ~',xt ] ~.'OR S'i'O-RAGE dF--d0~4[:~T:.:.: "HYDROGRAPH:
-' b: bl0dev.hyd
SPECIFY: C - CONTINUE N - NEWSTORM P - PRINT S - STOP
! , . ,
1
S.C.S. TYPE-lA RAINFAn.L DISTRIBUTION
ENTER' FREQ(Y:.:AR), DURAT[(]N(HOUR), ~RECIP(INCHES)
100,24,3.2
:~'*-%~,~'~'******* S.C.S. TYP:.:-].A 0ISTRIBUTION
********* 100-YEAR 24-HOUR STORM **** 3.20" TOTAL PRECIP. ***~*****
EN'.:'ER: A(PERV), CN(PERV),
1.03,86,0.33,98,~] .42
CN(IMPERV), TC FOR BASIN NO. 1
DATA P)<]NT-OUT:
AREA(ACRES) PERVIOUS
A CN
1.4 1.0 86.0
I.~PERV] OUS TC(M] NUTES)
A CN
.3 98.0 1] .4
PEAFi - Q ( ,.,~ ~:':3 ) T-PEAK(~i~RS) VOL(CU-FT) · 69 7 . 83 10406
~:NTER Id: ]llpath]~i.l:~,name[.ext] FOR STO~.AGE ~.)~.' COMPUTED HYDROGRAPH:
-'~6~ l'.,.1. 00dev. hyd
SP}<C.IFY' C - CONTINUE, N NEWSTORM, P - P~<~NT, S - STOP
1
ENTER' POND SIDE SLOPE (HORIZ. COMPONENT)
3
E" 'R: EFFECTIVE STORAGE DEPTH(ft) BEFORE OVERFLOW
3
ENTER [d-][path]filename[.ext.] OF PRIMARY DESIGN INFLOW HY~)ROGRAPH'
.A- 81 OODEV. HYD
PRIMARY DESIGN INFLOW PEAK : .69 CFS
ENTER PRIMARY DESIGN RELEASE RATE(cfs)'
0.22
ENTER NUMBER OF INFLOW HYDROGRAPHS TO BE TESTED FOR PERFORMANCE (5 MAXIMUM)'
1
ENTER [d-][path]filename[.ext] OF HYDROGRAPH l-
A- B2DEV. HYD
ENTER TARGET RELEASE RATE{cfs)'
0.015
ENTER' NUMBER OF ORIFICES, RISER-HEAO(ft), RISER-DIAMETER(in)
2,3,12
RISER OVERFLOW DEPTH FOR PRIMARY PEAK INFLOW = .17 FT
SPECIFY ITERATION DISPLAY: Y - YES, N - NO
N
Sr.¢!FY' R - REVIEW/REVISE INPUT, C - CONTINUE
C
INITIAL STORAGE VALUE FOR ITERATION PURPOSES' 3255 CU-FT
BOTTOM ORIFICE' ENTER Q-MAX(cfs)
A
@OTTOM ORIFICE: ENTER Q-MAX(CfS)
0.025
DIA.= .73 INCHES
TOP ORIFICE: ENTER HEIGHT(ft)
2.47
O!A,= 3,14 INCHES
PERFORMANCE' INFLOW TARGET-OUTFLOW ACTUAL-OUTFLOW PK-STAGE STORAGE
DESIGN HYO' .69 ,22 .22 3.00 2838
TEST HYD 1' .20 .01 .02 2.47 2080
SPECIFY' O - DOCUMENT, R - REVISE, A - ADJUST ORIF, E - ENLARGE, S - STOP
O
PERFORMANCE' INFLOW TARGET-OUTFLOW ACTUAL-OUTFLOW PK-STAGE -STORAGE
...
0ESTGN HYO' .69 .22 .22 3.00 2838
'T HY0 1' .20 .01 .02 2.47 2080
563
RISER-HEAD
3.00 FT
POND-BOTTOM-AREA
439.1 SQ-FT
TOP-AREA(@1 'F.B. )
2081.9 SQ-FT
STOR-DEPTH
3.00 FT
DOUBLE ORIFICE RESTRICTOR:
BOTTOM ORIFICE:
TOP ORIFICE:
ROUTING DATA:
DIA (INCHES) HT (FEET) Q-MAX (CFS)
.73 .00 .025
3.14 2.47 .195
STAGE(FT) DISCHARGE(CFS) 'STORAGE (CU-FT) PERM-AREA (SQ-FT)
.00 .00 .0 .0
.30 .01 144.0 .0
· 60 .01 314.0 .0 :
· 90 .01 511.9 ,0
1,20 ,02 739.6 .0
1.50 ,02 999, 1 ,0
1.80 .02 1292.3 ,0
2,10 .02 1621,2 .0
2.40 ,02 1987,7 ,0
2.47 ,02 2078,9 ,0
2,70 · 15 2393,8 .0
3,00 ,22 2841,3 ,0
3.10 ,55 3000.1 .0
3,20 1,13 3163.7 ,0
3.30 1.87 3332,3 ,0
3.40 2.68 3506.0 .0
3,50 2.97 3684.7 ,0
AVERAGE VERTICAL PERMEABILITY: .0 MINUTES/INCH
S~-S!FY: F - FILE, N - NEWJO8, P - PRINT IF/OF, R - REVISE,
ENTER [d:][path]filename[.ext] FOR STORAGE OF ROUTING DATA:
A:B100,OET
SPECIFY: F - FILE, N - NEWJOB, P - PRINT IF/OF, R - REVISE,
STORAGE-VOLUME
2838 CU-FT
S - STOP
S - STOP
ENTER' TANK DIAMETER (ft), EFFECTIVE STORAGE DEPTH (ft)
4,4
E .R [d'][path]filename[.ext] OF PRIMARY DESIGN INFLOW HYDROGRAPH'
A-BIOODEV.HYD
PRIMARY DESIGN INFLOW PEAK : .69 CFS
ENTER PRIMARY DESIGN RELEASE RATE(cfs)-
0.22
ENTER NUMBER OF INFLOW HYDROGRAPHS TO BE TESTED FOR PERFORMANCE (5 MAXIMUM)'
1
ENTER [d-][path]filename[.ext] OF HYDROGRAPH I'
A- 82DEV. HYD
ENTER TARGET RELEASE RATE(cfs)-
0.015
ENTER' NUMBER OF ORIFICES, RISER-HEAD(ft), RISER-DIAMETER(in)
2,4,12
RISER OVERFLOW DEPTH FOR PRIMARY PEAK INFLOW = .17 FT
SPECIFY ITERATION DISPLAY- Y - YES, N - NO
A
BOTTOM ORIFICE: ENTER Q-MAX(cfs)
0 ~
O.. .= .74 INCHES
TOP ORIFICE: ENTER HEIGHT(ft)
2.68
DIA.= 2.47 INCHES
PERFORMANCE' INFLOW TARGET-OUTFLOW ACTUAL-OUTFLOW PK-STAGE STORAGE
DESIGN HYD: .69 .22 .22 3.99 2829
TEST HYD 1' ,20 .01 .02 2.66 1990
SPECIFY' D - DOCUMENT, R - REVISE, A - ADJUST ORZF, E - ENLARGE, S - STOP
D
PERFORMANCE' INFLOW TARGET-OUTFLOW ACTUAL-OUTFLOW PK-STAGE STORAGE
DESIGN HYD' .69 .22 .22 3.99 2829
TEST HYD 1' .20 .01 .02 2.66 1990
563
~ISE.R-~EAD - TANK-DIAM STOR-DEPTH TANK-LENGTH STORAGE-VOLUME
4.00 FT 4.00 FT 4.00 FT 225.4 FT 2829 CU-FT
;OUBLE ORIFICE RESTRICTOR:
BOTTOM ORIFICE'
TOP ORIFICE'
DIA(INCHES) HT(FEET) Q-MAX(CFS)
· 74 . O0 .030
2,47 2,68 . 190
qOUTING DATA:
STAGE(FT) DISCHARGE(CFS) STORAGE(CU-FT) PERM-AREA(
.00 .00 .0 .0
.40 .01 147.4 .0
· 80 .01 403.3 .0
1,20 ,02 714,7 ,0
1,60 ,02 1058,1 ,0
2.00 ,02 1416,3 ,0
2,40 ,02 1774,5 ,0
2,68 ,02 2017,4 ,0
2,80 ,08 2117,9 ,0
3.20 ,15 2429,3 ,0
3,60 ,19 2685,2 ,0
4,00 ,22 2832,6 ,0
4.10 .54 2832.5 ,0
4,20 1,11 2832.6 ,0
~,30 1,84 2832,6 ,0
4.40 2,6a 2832,6 ,0
4,50 2,93 2832,6 .0
SQ-FT)
qVERAGE VERTICAL PERMEABILITY' .0 MINUTES/INCH
~? ~FY' F - FILE, N - NEW JOB, P - PRINT IF/OF, R - REVISE,
--
S - STOP
ENTER [d-][path]filename[.ext] FOR STORAGE OF ROUTING DATA'
A'BIOO,TNK
SPECIFY' F - FILE, N - NEWJO8, P - PRINT IF/OF, R - REVISE,
S - STOP
563198
APPENDIX C
I. Erosion and Sediment Control
II.
III.
IV.
.
2.
3.
4.
5.
.
7.
8.
9.
10.
11.
12.
13.
14.
15.
Stabilization and Sediment Trapping
Delineate'Clearing and Easement Limits
Protection of Adjacent Properties
Timing and Stabilization of Sedimentation measures
Cut and Fill Slopes
Controlling Off-site Erosion
Stabilization of Temporary Conveyance Channels and Outlets
Storm Drain Inlet Protection
Underground Utility Construction
Construction Access Routes
Removal of Temporary BMPs
De-watering Construction Sites
Control of Pollutants Other than Sediment on Construction Sites
Maintenance
Financial Liability
Preservation of Natural Drainage Systems
lo
Maintain natural drainage patterns to maximum extent practicable.
Discharges from site should occur at natural location to maximum extent
practicable.
Source Control of Pollution
o
Apply approved source control BMPs to maximum extent practicable.
Basin Plan (see Large Parcel Minimum Requirement #9) may be used to develop
source control BMPs tailored for a specific basin.
Runoff Treatment BMPs
o
.
Provide treatment of stormwater.
Size treatment BMPs for water quality design storm (6-month, 24-hour return
period).
Use infiltration to fullest extent practicable.
Use treatment BMPs as described in an approval manual. BMPs shall not be built
within natural vegetated buffer, except for necessary conveyance systems as
approved.
.
Basin Plan (see Large Parcel Minimum Requirement #9) may be used to develop
stormwater treatment requirements tailed for a specific basin.
V. Streambank Erosion Control
VI.
.
.
.
.
.
Limit peak rate of runoff from developed site to 50 percent of existing condition
2-year, 24-hour design storm.
Maintain existing condition peak runoff rates from developed sit for the 10-, and
100-year, ~24-hour design storms.
Use infiltration to fullest extent practicable. Stormwater must be treated before
direct discharge into groundwater.
Use streambank erosion control BMPs as 'described in an approved manual.
B~[Ps shall not be built within natural vegetated buffers, except for necessary
conveyance systems as approved.
Basin Plan ( see Large Parcel Minimum Requirement #9) may be used to develop
streambank erosion control requirements tailored for a specific basin.
Wetlands
VII.
.
.
.
.
.
Control and treat stormwater discharges to wetlands to meet State Water Quality
Standards and Ground Water Quality Standards.
Discharge to wetland only after evaluation alternative discharge locations.
Discharges shall maintain hydroperiod and flows of existing conditions to extent
necessary to protect characteristic uses.
Constructed wetlands used for treatment must be constructed in non-wetland area
and managed for stormwater treatment. Discharges are regulated.
No stormwater discharge to create wetlands used for mitigation.
Stormwater treatment BMPs shall not be built within natural vegetated buffer,
except for necessary conveyance systems as approved.
Basin Plan (see Large Parcel Minimum Requirement #9) may be used to develop
wetlands requirements tailored for a specific basin.
Water Quality Sensitive Areas
.
2:
.
More stringent controls may be required by the local government for protection
of water quality sensitive areas.
Stormwater treatment BMPs shall not be built within natural vegetated buffers,
except for necessary conveyance systems as approved.
Basin Plan (see Large Parcel Minimum Requirement #9) may be used to develop
water quality sensitive areas requirements tailored for a specific basin.
VIII. Off-site Analysis and Mitigation
Conduct analysis of off-site water quality impacts resulting from the project and
mitigate these impacts. Analysis shall extend a minimum, of one-fourth mile
·
IX.
X.
XI.
,
downstream from project.
Existing or potential impacts include, but are not limited to, excessive
sedimentation, streambank erosion, d!scharges to groundwater, violations of water
quality standards, spills and discharges of priority pollutants.
Basin Planning
o
,
Minimum Requirements #3-7 may be modified by adopted and implemented basin
plans, provided the level of protection for surface or ground water achieved will
equal or exceed that produced by implementation of the Minimum Requirements.
Basin plans shall be developed in accordance with an approved manual, and may
include retrofitting of BMPs for watershed wide pollutant reduction.
Operation and Maintenance
Identify responsible party, and provide schedule of operation and maint6nance
activities for all proposed stormwater facilities and BMPs.
Financial Liability
lo
Performance bonding or other appropriate financial instruments to ensure
compliance with these standards.
-- ~m ~
563
MACL~ARNSB~RRY,
Civil Engineers o Land Surveyors o Planners
ts9 W~A~T WAY SS SnJSSaZXX~S mLAm), WA ~no
PHOI~IE: (206) 842:~5'1'~i ....
BY
POPE RESOURCES
INDIVIDUAL LOT
DETENTION POND DETAIL
CAH DATE.OCTOBER 28, 1996 NO. 95034
blCM 1" ~-- 50' SHEET 2 OF 2
I-r1
Civil Engineers o Land Surveyors o Planners
159 WYATr WAY NE BAINBRIDOE ISLAND, WA 98110
PHONE: (206) 842-5514
ltl
I-rI
U) r-
o
~C
T
DRAWN BY
POPE RESOURCES
INDIVIDUAL LOT
DETENTION POND DETAIL
MCM D^~ OCTOBER 28. 1996 a3a N~ 95034.
MCM 1" = 4' s~r I 0~2