HomeMy WebLinkAboutStormwater Site Plan and Erosion Control Plan - PLN General - 10/28/1997 MASON COUNTY
PUBLIC WORKS DIRECTOR/COUNTY ROAD ENGINEER
Shelton,W.Ju gton 98584
DATE: Oct. 28, 1997
INTER-DEPARTMENTAL COMMUNICATIONS
TO: Randy Neff, DCD - Subdivision Planner
FROM: Alan A. Tahja, P/W - Co. Hydr. Engr.
SUBJ: Stormwater Site Plan Review NAME: Island West Associates
County Tax Parcel No 32124-75-00140
A Stormwater Site Plan (SSP) including permanent features as well as temporary erosion and
sediment control features has been received by Public Works for the Island West Associates
development activities relating to Mason County Tax Parcel 32124-75-00140.
The plan addresses road associated runoff, providing for treatment of water quality design storm
events, and flow attenuation of storm events up to a 100 year event.
Accompanying the plan were two instruments pertaining to easements, and a recorded Operation
and Maintenance Covenant. The two easement documents were recorded, with one terminating
an unneeded easement, and the other creating easements necessary for siting the proposed
stormwater control ponds. The easements appear to be in order. The O&M Covenant also
appears to conform to the County's standard form, and is considered adequate and acceptable.
The only matter remaining is the inspection and approval of the completed stormwater control
features. Before building permits are issued to any of the parcels relying on the function of the
designed stormwater features, the stormwater control elements need to be completed by the
proponent and approved by Public Works.
Please keep me informed of the progress of any stormwater feature construction. Public Works
will likewise keep you informed of the completion and acceptance of the stormwater control
features.
Please feel free to contact me at County 461 if any of this review needs clarification or if issues
remain needing further attention.
SillceAely,
At., r7wz�;,
Alak A. Tahja
File: H:\WP\STRMWTR\REVIEWS\I-WEST.CAT
GARY YANDO,DIRECTOR
SON.STATFO
o A ou DEPARTMENT OF COMMUNITY DEVELOPMENT
o T z PLANNING -SOLID WASTE - UTILITIES
2� N Y Y BLDG. I • 411 N. 5TH ST. • P.O. BOX 578
of ��1864 SHELTON,WA 98584 • (360) 427-9670
October 29 , 1997
Island West Associates
Attn: Keith Fuller & Dan Holman
P.O. Box 2379
Shelton, WA 98584
RE: Stormwater Plan for Par.# 32124-75-00140
Dear Keith & Dan:
The following comments were generated by Mason County Public
Works review of your proposed stormwater plan. Mason County will
require you to have the facilities built prior to any building
permits being issued.
A Stormwater Site Plan(SSP) including permanent features as well as temporary erosion and
sediment control features has been received by Public Works for the Island West Associates
development activities relating to Mason County Tax Parcel 32124-75-00140.
The plan addresses road associated runoff, providing for treatment of water quality design storm
events, and flow attenuation of storm events up to a 100 year event.
Accompanying the plan were two instruments pertaining to easements, and a recorded Operation
and Maintenance Covenant. The two easement documents were recorded, with one terminating
an unneeded easement, and the other creating easements necessary for siting the proposed
stormwater control ponds. The easements appear to be in order. The O&M Covenant also
appears to conform to the County's standard form, and is considered adequate and acceptable.
The only matter remaining is the inspection and approval of the completed stormwater control
features. Before building permits are issued to any of the parcels relying on the function of the
designed stormwater features, the stormwater control elements need to be completed by the
proponent and approved by Public Works.
Please keep me informed of the progress of any stormwater feature construction. Public Works
will likewise keep you informed of the completion and acceptance of the stormwater control
features.
If you have any questions regarding these comments, please
contact Alan Tahja at 427-9670, ext . 461 .
Sincerely,
Randy Neff
Subdivision Planner
GARY YANDO,DIRECTOR
SON.STgTFO
o A ou N DEPARTMENT OF COMMUNITY DEVELOPMENT
o T z PLANNING -SOLID WASTE - UTILITIES
N Y y BLDG. I • 411 N. 5TH ST. • P.O. BOX 578
rasa SHELTON,WA 98584 • (360) 427-9670
October 29 , 1997
Island West Associates
Attn: Keith Fuller & Dan Holman
P.O. Box 2379
Shelton, WA 98584
RE: Stormwater Plan for Par.# 32124-75-00140
Dear Keith & Dan:
The following comments were generated by Mason County Public
Works review of your proposed stormwater plan. Mason County will
require you to have the facilities built prior to any building
permits being issued.
A Stormwater Site Plan (SSP) including permanent features as well as temporary erosion and
sediment control features has been received by Public Works for the Island West Associates
development activities relating to Mason County Tax Parcel 32124-75-00140.
The plan addresses road associated runoff, providing for treatment of water duality design storm
events, and flow attenuation of storm events up to a 100 year event.
Accompanying the plan were two instruments pertaining to easements, and a recorded Operation
and Maintenance Covenant. The two easement documents were recorded, with one terminating
an unneeded easement, and the other creating easements necessary for siting the proposed
stormwater control ponds. The easements appear to be in order. The O&M Covenant also
appears to conform to the County's standard form, and is considered adequate and acceptable.
The only matter remaining is the inspection and approval of the completed stormwater control
features. Before building permits are issued to any of the parcels relying on the function of the
designed stormwater features, the stormwater control elements need to be completed by the
proponent and approved by Public Works.
Please keep me informed of the progress of any stormwater feature construction. Public Works
will likewise keep you informed of the completion and acceptance of the stormwater control
features.
If you have any questions regarding these comments, please
contact Alan Tahja at 427-9670, ext. 461 .
Sincerely,
Randy Neff
Subdivision Planner
Lefler Development Consultants
Rick Leffler 2337 Olympic Hwy.N.Shelton WA. 98584 P.O.Box 601
Marley L. Young PE.PLS. (360)426-39 24 FAY 4 26-4159
OWNERS TO DO LIST
STORMWATER SITE PLAN AND EROSION CONTROL PLAN for
ISLAND WEST ASSOC. 5 acres on Catfish Place road.
Enclosed is a PRELIMINARY REPORT. Prior to submittal to the
County and in order to complete this Report the owners is required to
provide the following information:
1) Prepare Drainage Easements to include the Ponds and the
Discharge Roots.
2) Prepare a Drainage Easement from the abutting property
(SO 2551) allowing Pond 'A' to occupy its assess Easement.
3) Prepare and Record with the County Auditor, the
"DECLARATION OF COVENANTS ASSOCIATED
WITH PRIVATELY MAINTAINED STORM DRAINAGE
FACILITIES" blank copy included in this Preliminary
Report. Note: evidence of recording must be included in this
report or furnished the Mason County Department of
Community Development.
Marley L. Young � A'0 d
10 01/
r
ti
STORMWATER. SITE PLAN
AND
EROSION CONTROL PLAN
ISLAND WEST ASSOC.
INTERIOR ROAD
Property Located in
NE 1/4 of the SE 1/4 of
Sec. 34, T.21N., R.3N., W.M.,
in Mason County
requested by
DAN HOLMAN
P.O. Box 2379
Shelton, WA 98584
(360)426-2990
Prepared by
LEFFLER DEVELOPMENT CONSULTANTS
P. 0. Box 601
2335 Olympia Hwy. N.
Shelton WA 98584
(206) 426-3924
Project No. 96-23
Oct.28, 1996
Island West Assoc.
Catfish Area SSP
TABLE OF CONTENTS
Page
g
Need and Purpose ............................................... 1
Best Management Practices ............................................... 1-3
Proposed Project Description ............................................... 3-4
Existing Conditions .....................I......................... 4
Basin Descriptions .............................I................. 5
SCS Soils Description .....................I......................... 5-6
Wetlands or Water of the State ............................................... 6
Analysis of the 100-Year Flood ............................................... 6
Storm Event Assumptions ............................................... 7
StormEvent ............................................... 7
DrainageBasin ............................................... 7
Special Specifications ............................................... 8
Interior Road - Design Results- Stormwater Control ................................ 8
Roadway Station 0+00 to 1+00 ............................................... 8-9
Roadway Station 1+00 to 4+00 ............................................... 9-10
Roadway Station 4+00 to 6+65 .........................I..................... 11-13
Downstream Analysis ............................................... 14
Erosion Control Plan ............................................... 14
Maintenance Plan ............................................... 15
Declaration of Covenant ............................................... 15
Changed Conditions ............................................... 15
Engineer's Certification ............................................... 16
***************************************************************
ATTACHMENTS:
Vicinity Maps
Declaration of Covenants Associated with
Privately Maintained Storm Drainage Facilities
DESIGN DETAILS of the STORMWATER and EROSION CONTROL PLAN
SUPPORTING CALCULATIONS
i
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STORMWATER SITE PLAN
AND
EROSION CONTROL PLAN
FOR
ISLAND WEST ASSOC.
by request of
Dan Holman
P.O. Box 2379
Shelton, WA 98584
(360) 426-2990
5.03 Acres Proposed Short Plat
Located in the NE1/4, of the SE114
of Sec. 34, T. 21 N., R. 3, W.M.
NEED AND PURPOSE
The Puget Sound Water Quality Management Plan (PSWQMP) which is administered by the
State of Washington Department of Ecology mandates that all counties and cities within the
Puget Sound drainage basin adopt ordinances to control runoff from new development and
redevelopments. The PSWQMP also directs local governments to adopt stormwater programs
which must include minimum requirements that are consistent with the PSWQMP, and that are
substantially equivalent to the DOE's Stormwater Management Manual for the Puget Sound
Basin, (DOE's Technical Manual).
The goal of the Puget Sound Water Quality Management Plan is to
► Protect and restore beneficial uses of aquatic resources, including shellfish beds, fish
habitat, and other resources;
► Prevent contamination of sediments from urban runoff;
► Meet standards for water and sediment quality by reducing pollutant discharges from
stormwater throughout Puget Sound.
BEST MANAGEMENT PRACTICES (BMPs)
Best management practices (BMPs) are defined as physical, structural, or management practices
that, when used singly or in combination, prevent or reduce pollution of water. Specific BMPs
have been developed by Ecology to control stormwater runoff(quality and quantity) for
protection of receiving waters.
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There are three main reasons for applying BMPs before considering advanced treatment:
First, it has been shown through research and experience that BMPs can significantly reduce
pollutants in stormwater. Using BMPs to control localized discharges is cost effective in
comparison to Treating large volumes of water.
Second, our lakes and streams depend on stormwater to provide adequate flow for fish habitat
and water quality. Our groundwater resources also depend on stormwater for recharge. BMP
implementation offers a way to discharge water back into the natural system.
Third, and perhaps most important, stormwater management programs demand the
conscientious use of best management practices to protect water quality.
Specific BMPs that cover stormwater runoff quality and quantity have been included in
Ecology's Technical Manual. Those BMPs can be divided into three basic categories, including
Source Control BMPs, Runoff Treatment BMPs and Streambank Erosion Control BMPs.
Source Control BMPs are designed to prevent pollutants from entering stormwater by
eliminating the source of pollution or by preventing contact of pollutants with rainfall and runoff.
Source controls are usually the most cost-effective because they reduce or eliminate the need for
treatment BMPs. Implementing source control BMPs generally involves relatively simple and
straightforward actions. Examples of source control BMPs include erosion control (e.g.,
covering disturbed soil), covering material storage areas, and eliminating illicit discharges.
Runoff Treatment BMPs are designed to remove pollutants contained in stormwater runoff.
These types of BMPs are the second line of defense in protecting stormwater quality. Examples
of runoff treatment BMPs include infiltration basins, biofiltration swales and sediment ponds.
Approximately one-half of the roadway will be free flowing after development From the
road centerline toward the roadside ditch will be treated by a I foot flat bottom ditch with
shallow 'check dams'in the ditch. The other side of the roadway will be treated by the use of
detention/retention ponds to capture and hold the six month storm events. The roadside
ditches (both sides) will assist in the treatment of the road runoff, and also act as
biofiltration swales and sediment containers. The calculated discharges are based on road
right of way only, no other areas are included in this Stormwater Site Plan.(mly)
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Three types of detention/retention facilities are being proposed to meet the Runoff Treatment
BMP's criteria:
1) Infiltration pockets along both sides of the roadway from station 0+00 to
1+00+/-
2) Special roadside flat bottom ditch sections, and
3) Standard trapezoidal basins
The gradients of the roadside ditch sections are 2%+/-to 3-1/2%+/-. The ditches that are
designed as free flowing will have ditch weirs (check dams) every 25'and 15'respectively.
The trapezoidal basins are expected to, as a minimum, retain the storm events so that the
combined discharges will not exceed the pre-developed 6 month, 2, 10 & 100 year storm
events.(mly)
Streambank Erosion Control BMPs are designed to protect stream ecosystems from erosion
and sedimentation. Types of streambank erosion control BMPs include flow attenuation BMPs
for reducing peak flows from a development (e.g., detention ponds, infiltration trenches), and
streamside stabilization BMPs used to stabilize eroding streambanks.
No year-around streams are near the proposed roadway system. Cranberry Creek is
approximately 1000 feet from this project. The retention of 50% of the 2 year storm will not
be included in this design. The difference between the Pre and Post-developed are small.
6 Month = 0.152 cfs; 2 Year=0.190 cfs; 10 Year= 0.225 cfs; 100 Year= 0.252 cfs
PROPOSED PROJECT IPTION•
This property contains 5.03+/- acres. The proposal is to divide the property into four parcels.
The Stormwater and Erosion Control Plan will mitigate only the impacts caused by the
additional runoff created by the road improvement.
The Department of Ecology has identified a major source of water contamination as coming
from the motor oils dripped onto the driving surfaces. Study results also have shown that these
contaminates are washed off the roads during 6 month storm events. When 6 month storm
events are retained, the probability of these contaminates entering our streams is greatly
reduced.
The traffic volume generated by four lots is considered minor, and the potential for traffic
related contaminates would be very small The road runoff from this project does not
directly enter any streams, therefore the potential for stream contamination is minimal(mly)
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The following is an outline of the detention/retention facilities proposed in this Plan:
A. Beginning at the intersection with Catfish Place, thence northerly:
1) Between Stations 0+00 and 1+00, the calculated increase in runoff caused by the
road development is to be held by infiltration trenches. These excavated pockets
are to be construction along both left and right ditch lines.
2) Between Station 1+00 and 4+00 drainage flows to the north. A detention/
retention facility(pond) is to be located right of Station 3+25+/-. The runoff from
the left ditch will be allowed to 'free flow', without detention, except for the ditch
weirs, 25' apart. The detention/retention facility will capture and hold the runoff
from the ditch on the right side of the road. The summation of discharges from
the left 'free flowing' ditch and the detention/retention facility will be less than the
calculated total pre-discharges. The detention/retention facility shall be located
in Lot 15B of the adjoining Short Plat, and be allowed by easement. The Facility
(pond) floor area is 150 sq. ft. (20'x T).
3) Between Station 4+00 and 6+65 drainage flows to the east toward Station 4+00.
A detention/retention facility(pond) is to be located left of Station 4+50+/-. The
runoff from the right ditch will be allowed to 'free flow', without detention,
except for the ditch weirs, 15' apart. The detention/retention facility will capture
and hold the runoff from the ditch on the left side of the road. The summation of
discharges from the left 'free flowing' ditch and the detention/retention facility
will be less than the calculated total pre-discharges. The detention/retention
facility shall be located in Lot 3 of this Short Plat. A culvert shall be installed at
Station 3+80+/-to allow the facility discharge and any natural drainage to flow in
a northeasterly direction.
These drainage control facilities will attempt to maximize infiltration, minimize the post-road
development runoff and aid in the recharge of ground water.
This Drainage Plan focuses only on the additional runoff that is created because of the road
improvement.
EXISTING CONDITIONS:
General Description
The segregation of this property into four lots is compatible with the rural residential
developments along this corridor.
The subject property is located on north of Catfish Place Road, a privately maintained road.
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BASIN DESCRIPTION:
A existing contours on this short plat show ground slopes of 2 to 8 percent. The Catfish Place
Road is lower than the property and requires a road approach of 8%+/-. The finished roadway
is expected to be constructed with all grades below 8 percent.
SCS SOILS DESCRIPTION:
The Soil Conservation Service - Soil survey of Mason County Series 1951, No. 9 Issued
September 1960, shows this property having soil type Alderwood gravelly sandy loam, 5-15
percent slopes (Ab).
ALDERWOOD SERIES
The Alderwood series consists of brown, well-drained, upland soils. They have developed from
mixed gravelly glacial till dominated by acid igneous rock. The imbedded gravel is mainly
granite and quartzite. Rainfall is 45 to 60 inches a year. The native vegetation is a dense forest
consisting almost entirely of Douglas-fir and a dense understory of salal, Oregon-grape, vine
maple, and huckleberry. Alderwood soils occupy the extensive rolling glacial moraines, and they
are the dominant soils in the eastern part of the county.
Alderwood gravelly sandy loam, S to IS percent slopes (Ab).-
This is the most extensive soil of the Alderwood series. It occupies undulation to rolling
moraines.
In undisturbed areas a 1-to 2-inch mat of very dark brown, acid organic matter is on the
surface. This grades to a thin, dark grayish-brown, highly organic mineral medium acid gravelly
sandy loam 8 to 13 inches deep. It has a weak granular structure and contains numerous
rounded shot. Below the surface soil, to depths ranging from 18 to 24 inches, is a pale-brown
gravelly sandy loam that is very friable, is single grained, and contains small to moderate
amounts of shot. Between this layer and the cemented till is a 3 to 10 inch layer of very pale
brown gravelly sandy loam. It contains no shot and is firmer but has the same texture as the
layer above. However, it is faintly to distinctly spotted and horizontally streaked with brown
and yellow. The cemented till consists of light-gray, gravelly sandy loam, and it normally occurs
at depths ranging from 24 to 32 inches. It is impermeable to roots and is usually laminated and
streaked with reddish brown and yellow. Below this layer soil is fairly uniform light gray, and
medium to strongly acid. A thin mat of roots often lies over the till.
The cemented substratum tends to restrict the rapid downward movement of moisture.
Use and suitability- Not more than about 5 percent of this soil has been cleared and is used for
crops or pasture. Most of the cultivated acreage is near the inlets of Puget Sound in the
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vicinities of Arcadia and Allyn. In this area the Alderwood soils are associated with the better
agricultural soils of the Cloquallum, Sinclair, and Kitsap series.
Hay, small grains, pasture, fruits, nuts, grapes, and berries are the principal crops grown on the
Alderwood soils. The lack of subsoil moisture damages crops in summer. For this reason early
maturing, short-season crops are suited best to this soil. Yields of all crops are usually fairly low
because of low fertility and the dry summers. Pastures produce good forage in spring and late in
fall if proper plants are used and management is good. The deeper soils are suited best to fruits,
nuts, and grapes. The uncleared and remote areas are better suited to forestry than to cultivated
crops.
Nearly all the uncleared acreage is in second-growth forest 70 to 80 years of age. Shallowness
to the compact till often inhibits growth of the older trees. The soil, however, is well suited to
production of Christmas trees. Douglas-fir readily restocks in thick stands containing trees of
good form. Stands of small trees are often thinned and pruned to maintain good form of
growth. The growing of Christmas trees has expanded rapidly in the past few years and is now
one of the important industries in the county. It is one of the proper uses of the cutover lands
that are not in a high site class.
This soil is in capability subclass VIs and is site class 4 and 5 for Douglas-fir. Small areas along
the border, where the soil is more than 32 inches deep to compact till, are in site classes 3 and 4
for Douglas-fir. Class VI -- Soils in class VI have severe limitations that make them generally
unsuitable for cultivation and limit their use largely to pasture or range, woodland, or wildlife
food and cover. Subclass VIs --- Coarse and moderately coarse textured, droughty soils, or
medium-textured soils of low fertility, occurring in belts of very high rainfall. Dominant and
codominant trees, at an age of 100 years in well-stocked stands growing on site class 3 soils will
reach heights ranging from 130 and 150 feet; on site class 4, heights of 100 to 120 feet.
WETLANDS OR WATER OF THE STATE:
This proposed roadway does not appear to be within 200 feet of any waters of the State.
ANALYSIS OF THE 100 YEAR FLOOD:
This site does not contain or abut a Federal Emergency Management Administration (FEMA)
identified stream and is, therefore, outside any 100 year flood plain.
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STORM EVENT ASSUMPTIONS: Based on DOE's Stormwater Management Manual:
■ STORM EVENT
■ Rain Precipitation(in.)
■ Six-month Storm Event 2.50
■ Two-year Storm Event 3.90
■ Ten-year Storm Event 5.40
■ Hundred-year Storm Event 7.50
■ Rainfall choice IA
■ Storm Duration (hr.) 24
■ Hydrograph SBUH**
** Santa Barbara Urban Hydrograph method
■ DRAINAGE BASIN
■ Hydrologic Soil Group C
■ Pre-existing Conditions at proposed road location:
■ Unimproved -Meadow and Pasture.
■ CN# -Unimproved 81
■ Post-Development Conditions: Gravel Roads, Grassed Ditches and Back Slopes.
■ CN#- Gravel or Paved two - 10 ft. driving lanes 98
■ CN# - Gravel Shoulders 89
■ CN# -Ditch 86
■ CN# -Back of Ditch 86
■ Roadway driving lanes 10 ft each 20 feet CN# 98.0
COMPOSITE CN# FOR SHOULDER, DITCH BOTTOM AND BACK OF DITCH
CN# 89x3 ft = 267
CN# 86 x 7 ft = 602
Unpaved Right-of-way 869 divided by IOft is 86.9
■ Ditch and back-of-ditch 10 ft wide each 20 feet CN# 86.9
This Report will focus only on the stormwater runoff associated with the road right-of-way.
NOTE: Given the Storm Event, Soil Type and Land Use, the Runoff Curve Number(CN#) is
an indicator of the total surface and subsurface runoff.
SPECIAL SPECIFICATION
The exact location and shape of each pond can be modified to fit field conditions. The pond's
volume and the square footage of the pond's floor are critical and must be respected. It is
desirable that the pond floors be a minimum of 2 feet below the original ground elevation. The
pond floor must be flat. The natural overburden materials excavated from the pond can be used
around the pond edge to build an earth berm approximately one-half foot above the original
ground elevation by 6 feet wide. The other excavated materials may be suitable for road
construction.
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The discharge structures from the ponds are overflow weirs. It must also be understood that
the distance, shown in this Report, from the pond floor to the overflow weir is a minimum
distance and must also be respected. The overflow outfall edge of the weir should be placed on
natural ground; The outfall end should be located so that erosion does not occur. To protect
the outfall area from erosion, quarry spalls may be required. The size of quarry spalls equaling
D50 of 0.25 is recommended.
INTERIOR ROAD-DESIGN RESULTS - STORMWATER CONTROL:
ROADWAY SECTION 0+00 to 1+00:
The Detention/Retention Facility will be infiltration trenches in both roadside ditches.
DITCH LINE INFILTRATION POCKETS:
This design requires pockets (trenches)to be excavated as filled with washed rock. The pockets
will provide detention/retention of the increase in flow caused by the road improvement.
Backfill material - The aggregate material for the infiltration trench shall consist of a clean
aggregate with a maximum diameter of 2.5 inches and a minimum diameter of 1.5 inches or
washed round rock 6 inch minus .
Aggregate Placement - the stone aggregate should be placed in lifts and compacted using plate
compactors. As a rule of thumb, a maximum loose lift thickness of 12 inches is recommended.
Note: The computer model used for this analysis of an infiltration trench with a void ratio of 33
percent, requires that the trench floor be shortened to 33% of actual. Also, the infiltration rate
for the computer model also must be increased by 3 times of actual. (Example: Trench floor
length of 16.8 feet actual x 0.33 = 5.60 feet computer model and infiltration rate of 45 minrnch
actual x 0.33 = 15 min/inch for model.
TABULATION OF THE HYDROGRAPHIC SUMMARY: Access Road 0+00 to 1+00:
The Ditch Line Infiltration Trench will consist of five 'Pockets' dug in the ditch line
conforming to the following dimensions, 3.4' wide with vertical sides by 7.0' long with
1:1 end slopes. All pockets to be filled with washed drain rock as per plan.
STORM EVENT 6 month Two-yea Ten-year 100-year
■ Pre-Flow -cfs 0.008 0.020 0.034 0.054 Allowable
■ Pre-Volume -cf 46 128 229 393
■ Post-Flow -cfs 0.018 0.031 0.046 0.067
■ Post-Volume -cf 141 257 389 579
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Ditch Line Infiltration Pocket -Trapezoidal Basin:
► Floor Length: -ft 7
► Floor Width: -ft 16.8 Total Width/ 5 pockets=3.4'
► Min. Depth: -ft 2.75
► Infiltration Rate -min/inch 45
► End Slopes: 1 ft horizontal to 1.0 ft vertical
► Side Slopes: Vertical
Discharge Structure- Broad Crested Weir- Discharging to the northeast:
► Inlet Elev.: -ft 2.75 distance from pond floor
► Weir Length: -ft 0.35
Infiltration Trench Discharge:
► Storm Event 6 month Two-year Ten-year 100-year
► Post-Flow -cfs 0.000 0.012 0.033 0.053
► Post-Volume -cf 0000 16 101 226
► Post-Depths -ft 2.48 2.79 2.82 2.84
► Pond-Volume -cf 140 164 166 168
Roadway Section 0+00 to 1+00+/- Trench Discharge Check:
► Storm Event 6 month Two-year Ten-year 100-year
► Post-Discharge -cfs 0.000 0.012 0.033 0.053
► Allowable -cfs 0.008 0.020 0.034 0.054 Pre-Flow
Credit -cfs 0.008 0.008 0.001 0.001
ok ok ok ok
NOTE: All final discharges are below pre-developed discharges.
ROADWAY SECTION 1+00 to 4+00+/-: North / South Section:
Because of the small drainage increases from Pre-developed to Post-developed, and the very
low volume of traffic to be generated by this land division, only one Detention/Retention Pond
will be used. One side of the roadway will be Free Flowing after development and the other side
will be detained in a pond. The sum of the discharges from the Free Flowing side and the
detention pond side will be less than the total-development detention.
The flow is from south to north at a 2 percent fall. A standard ditch is designed on the right and
a one-foot flat bottom ditch is designed for the left side of the roadway. The storm runoff from
the left roadside ditch will be free flowing and the storm runoff on the right roadside ditch will
be directed to a Detention/Retention Facility right of Station 3+25+/-.
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This design is based on the left (free flowing) side of the roadway right-of-way equaling 0.159
acres (pre-developed pervious CN# 81; post developed pervious acres of 0.076 with a CN# of
86.9 and impervious acres of 0.083 with a CN# of 98).
Pre-development for Left and Right Side of Roadway Section 1+00 to 4+00+/-•
► Storm Event 6 month Two-year Ten-year Hundred yr
► Left Pre Flow -cfs 0.020 0.053 0.090 0.148
► Right Pre Flow -cfs 0.015 0.039 0.066 0.109
► Total Allowable -cfs 0.035 0.092 0.156 0.256
Pre-and Post-development for Left Side of Roadway Section 1+00 to 4+00+/-•
► Storm Event 6 month Two-year Ten-year Hundred yr
► Pre Flow -cfs 0.020 0.053 0.090 0.148
► Pre Volume -cf 541 1,195 1,921 3,032
► Post Flow -cfs 0.056 0.099 0.145 0.209
► Post Volume -cf 1,046 1,809 2,650 3,822
Flat Bottom Ditch Left side of Roadway from Station 1+00 to 3+50+/- - Designed as a
Trapezoidal Basin:
► Floor Length: -ft 200 Minimum Length
► Floor Width: -ft 1
► Min. Depth: -ft 0.25
► Infiltration Rate -min/inch 45
► Roadside Slopes: 3 ft horizontal to 1.0 ft vertical - max.
► Back of Ditch Slope 1 ft horizontal to 1.0 ft vertical - max.
Flat Bottom Ditch Left side of Roadway calculated Free Flowing Discharges:
► Storm Event 6 month Two-year Ten-year 100-,year
► Post-Flow -cfs 0.031 0.071 0.117 0.179
► Post-Volume -cf 164 583 1239 2292
► Post-Depths -ft 0.32 0.36 0.39 0.42
► Pond-Volume -cf 125 149 169 192
This design is based on the right (pond detention) side of the roadway right-of-way equaling
0.117 acres (pre-developed pervious CN# 81; post developed pervious acres of 0.06 with a CN#
of 86.9 and impervious acres of 0.06 with a CN# of 98).
Leffler Development Consultants
1 O Project#96-23
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Island West Assoc.
Catfish Area SSP
Pre-and Post-development for Right Side of Roadway Section 1+00 to 4+00+/
► Storm Event 6 month Two-year Ten-year Hundred yr
► Pre Flow -cfs 0.015 0.039 0.066 0.109
► Pre Volume -cf 398 879 1,414 2,231
► Post Flow -cfs 0.040 0.071 0.105 0.153
► Post Volume -cf 745 1,300 1,912 2,783
Pond right of Station 3+25+/- -Trapezoidal Basin:
► Floor Length: -ft 20
► Floor Width: -ft 7
► Min. Depth: -ft 2.5
► Infiltration Rate -min/inch 45
► Side Slopes: 3 ft horizontal to 1.0 ft vertical
Discharge Structure- Broad Crested Weir- Discharging to the northeast:
► Inlet Elev.: -ft 2.00 distance from pond floor
► Weir Length: -ft 0.50
Pond Discharge:
► Storm Event 6 month Two-year Ten-year 100-year
► Post-Flow -cfs 0.000 0.000 0.004 0.072
► Post-Volume -cf 0000 0000 46 710
► Post-Depths -ft 0.89 1.52 2.02 2.10
► Pond-Volume -cf 197 443 711 761
Roadway Section 1+00 to 4+00+/- Pond Discharge Check:
► Storm Event 6 month Two-year Ten-year 100-year
► Ditch Discharge -cfs 0.031 0.071 0.117 0.179 Left-Side
► Pond Discharge -cfs 0.000 0.000 0.004 0.074 Right-Side
► Total Discharge -cfs 0.031 0.071 0.121 0.253
► Allowable -cfs 0.035 0.092 0.156 0.256
► Credit 0.004 0.021 0.035 0.003
ok ok ok ok
NOTE: All final discharges are below pre-developed discharges.
ROADWAY SECTION 4+00 to 6+65• Because of the small drainage increases from Pre-
developed to Post-developed, and the very low volume of traffic to be generated by this land
division, only one Detention/Retention Pond will be used. The right side of the roadway will
be Free Flowing after development and the left side will be detained in a pond. The sum of the
Leffler Development Consultants
11 Project#96-23
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Island West Assoc.
Catfish Area SSP
discharges from the Free Flowing side and the detention pond side will be less than the total pre-
development discharge.
The flow is from west to east at a 3-1/2 percent fall. A standard ditch is designed on the left and
a one-foot flat bottom ditch is designed for the right side of the roadway. The storm runoff
from the right roadside ditch will be free flowing and the storm runoff on the left roadside ditch
will be directed to a Detention/Retention Facility left of Station 4+30+/-.
This design is based on the right (free flowing) side of the roadway right-of-way equaling 0.167
acres (pre-developed pervious CN# 81; post developed pervious acres of 0.085 with a CN#of
86.9 and impervious acres of 0.082 with a CN# of 98).
Pre-development for Left and Right Side of Roadway Section 4+00 to 6+75+/-•
► Storm Event 6 month Two-year Ten-year Hundred yr
► Right Pre Flow -cfs 0.021 0.057 0.097 0.159
► Left Pre Flow -cfs 0.023 0.061 0.104 0.170
► Total Allowable -cfs 0.045 0.118 0.201 0.329
Pre-and Post-development for Right Side of Roadway Section 4+00 to 6+75+/-•
► Storm Event 6 month Two year Ten-year Hundred
► Pre Flow -cfs 0.023 0.061 0.104 0.170
► Pre Volume -cf 166 469 844 1,454
► Post Flow -cfs 0.058 0.103 0.152 0.221
► Post Volume -cf 498 910 1,379 2,058
Flat Bottom Ditch Right side of Roadway from Station 4+00 to 5+75+/- - Designed as a
Trapezoidal Basin:
► Floor Length: -ft 125 Minimum Length
► Floor Width: -ft 1
► Min. Depth: -ft 0.25
► Infiltration Rate -min/inch 45
► Roadside Slopes: 3 ft horizontal to 1.0 ft vertical - max.
► Back of Ditch Slope 1 ft horizontal to 1.0 ft vertical - max.
Flat Bottom Ditch Right side of Roadway calculated Final Free Flowing Discharges
► Storm Event 6 month Two-year Ten-year 100-year
► Post-Flow -cfs 0.044 0.087 0.135 0.202
► Post-Volume -cf 237 576 997 1632
► Post-Depths -ft 0.32 0.36 0.39 0.42
► Pond-Volume -cf 80 93 104 118
Leffler Development Consultants
12 Projed#96-23
cAislandw3.swc
Island West Assoc.
Catfish Area SSP
This design is based on the left (pond detention) side of the roadway right-of-way equaling
0.179 acres(pre-developed pervious CN# 81; post developed pervious acres of 0.07 with a CN#
of 86.9 and impervious acres of 0.109 with a CN# of 98).
Pre-and Post-development for Left Side of Roadway Section 4+00 to 6+75+/--
► Storm Event 6 month Two-year Ten-year Hundred yr
► Pre Flow -cfs 0.023 0.061 0.104 0.170
► Pre Volume -cf 166 469 844 1,454
► Post Flow -cfs 0.068 0.116 0.168 0.242
► Post Volume -cf 593 1,053 1,569 2,309
Pond left of Station 4+50+/- -Trapezoidal Basin:
► Floor Length: -ft 24
► Floor Width: -ft 12
► Min. Depth: -ft 2.5
► Infiltration Rate -min/inch 45
► Side Slopes: 3 ft horizontal to 1.0 ft vertical
Discharge Structure- Broad Crested Weir- Discharging to the northeast:
► Inlet Elev.: -ft 2.00 distance from pond floor
► Weir Length: -ft 0.50
Pond Discharge:
► Storm Event 6 month Two-year Ten-year 100-year
► Post-Flow -cfs 0.000 0.000 0.000 0.119
► Post-Volume -cf 0000 0000 0000 551
► Post-Depths -ft 0.80 1.42 1.97 2.13
► Pond-Volume -cf 305 660 1080 1218
Roadway Section 4+00 to 6+75+/- Pond Discharge Check:
► Storm Event 6 month Two-year Ten-year 100-year
Ditch Discharge -cfs 0.044 0.087 0.135 0.202
Pond Discharge -cfs 0.000 0.000 0.000 0.119
► Total Discharge -cfs 0.044 0.087 0.135 0.321
► Allowable -cfs 0.045 0.118 0.201 0.329
► Cr it 0.001 0.031 0.066 0.008
ok ok ok ok
NOTE: All final discharges are below pre-developed discharges.
Leffler Development Consultants
13 Project#96-23
c:\islandw3.swc
Island West Assoc.
Catfish Area SSP
DOWNSTREAM ANALYSIS:
With the Post-discharge being less than the Pre-discharge, no downstream analysis is required
and no negative impact to the downstream drainage system is expected. As long as the Post-
Development conditions are as assumed, this project is expected to improve the downstream
drainage by infiltration and by releasing surface water at a slower rate than was possible under
pre-developed conditions.
EROSION CONTROL PLAN:
The Owner should consider protecting all construction areas from sediment and erosion in order
to provide a more efficient construction zone.
It shall be understood that erosion control techniques that prevent soil from eroding, rather than
treating contaminated runoff, are preferred. The migration of sediment either into the delineated
wetlands or off site will not be tolerated. The Owners will not permit mud and debris to be
tracked onto the Catfish Place Road.
The necessary facilities shall be maintained on site to prevent the migration of sediment and
debris, dust and mud from accumulation on to Catfish Place Road.
All pollutants other than sediment that occur on-site during construction shall be handled and
disposed of in a manner that does not cause contamination of stormwater.
To prevent the possibility of erosion at the pond sites, quarry spalls should be placed where
stormwater flows into and out of the detention/retention ponds. Quarry spalls sized D50=0.25.
Hay bales shall be installed along the roadside ditch line as check dams and maintained through
the first winter to help prevent erosion and sediment migration. Recommend that the hay bale
check dam be installed as the same frequency as the rock check dam as per plan.
Hay bale check.dams shall be installed at the out flow of each detention/retention pond.
These hay bale check dams shall be maintained through the first winter. All disturbed soils
including the front and back of ditch shall be seeded to grass within 30 days after the final
sloping. Under no circumstance should the disturbed soil be allowed to winter unseeded.
Leffler Development Consultants
14 Project#96-23
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Island West Assoc.
Catfish Area SSP
MAINTENANCE PLAN
The responsibility for maintaining the facilities will lie with the owners of the property. The
facilities are designed to minimize the need for extensive maintenance. The ditches and basins
shall be inspected each fall to assure that the drainage flows as intended. As a minimum, after
each 2 year storm the facilities should again be inspected to assure that they are functioning
properly. The major maintenance activity will be to inspect the bottom of the basins for silt
build-up. If the infiltration capacity of the basins is compromised by silt build-up, the silt must
be removed.
DECLARATION OF COVENANT
Mason County requires that a DECLARATION OF COVENANTS ASSOCIATED WITH
PRIVATELY MAINTAINED STORM DRAINAGE FACILITIES be executed and filed with
the County as part of the approval process. A copy is attached.
CHANGED CONDITIONS
The conclusions and recommendations in this report are based on my interpretation of site
conditions, and the expectation that my on-site exploratory efforts adequately define the surface
and sub-surface conditions throughout the site. In the event that the scope of the project or
location of the improvements or surface/subsurface conditions differ from those I relied on in
this report, I should be advised. At that time, a review of the changed conditions will be made
and alternative or remedial recommendations given as requested.
This Stormwater and Erosion Control Plan for the Interior Roads has been prepared by:
WAsti�G'L
�! U2 /O-ZCo -9� ��`' do . 0
,n O
Marley L. Youn P. L.S. Date: Z t
� i
�°p Q 14144 w '
Appendices '��J, �G/STEREO
ATTACHMENTS f�4NAL ECG t c'
Vicinity Map
Declaration of Convenants �11RES�3/5/,�/
DESIGN DETAILS OF THE DRAINAGE FACILITIES
SUPPORTING CALCULATIONS
Leffler Development Consultants
15 Project#96-23
c:islandw3.swc
Island West Assoc.
Catfish Area SSP
Lefler Development Consultants
Rick Leffler 233 7 Olympic Hwy.N. Shelton WA. 98584 P.O.Box 601
Harley L. Young PE.PLS. (360)426-3924 FAX 426-4159
ENGINEER'S CERTIFICATION
I hereby certify that this Stormwater Site Plan and Erosion Control Plan
for Island West Assoc. has been prepared by me or under my supervision
and meets minimum standards of Mason County and normal standards of
engineering practice.
Y L. y�U
�P OF WA
-7 Marley L. Y ing P.E P.L.S. z
14144 W
EXPIRES 3/5/�/y
Leffler Development Consultants
16 Project#96-23
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Island West Assoc.
Catfish Area SSP
ATTACHMENTS
Leffler Development consultants
Project#96-23
c:�slandw1swc
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SUBJECT PROPERTY
Parcel # 32124 75 00140
305.75 j 34.19- — \
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R-1577.36 R-1577.36
L- 146.77 (CALC) L- 146.83 (REC)
SHORT PLAT FOR SHORT PLAT # � �l
KEITH FULLER 603287
W. 200 SHADOW VALLEY DR. DATE APPROVED. -13`-957
SHELTON, WA. 98584
(206)426-1360 DIRECTOR OF MMUNI TT
BASIS OF BEARINGS DEVEL OPMENT
eARI11O1 IM1QI OPMY NAs N"A[]I'fM l.lt IrY
TO/u1L0 WIMAIN, IY9101i OR OfhCll.l!(
VOLUME 2 OF SURVEYS, PAGE 98 1p FROl DI SERVICE
Aunt orrtler"r MIN
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RECORDS OF MASON COUNTY, WA. w9mlow IN III[ox"T,lAr.
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AD""Y ONLY. MULL!MH"IM"
LEGAL DESCRIPTION rp "c"`"'°"°' r. `"r""`�"
n"al10F"M wM
TRACT 15 OF VOLUME 2 OF SURVEYS, SCALE: 1"-100'
PAGE 98, RECORDS OF MASON COUNTY, �—
WASHINGTON. AS ADJUSTED UNDER
MASON COUNTY SUPERIOR COURT 0 50 100 200
CAUSE 1/92-2-00152-1.
AP 1/32134-75-00150
EQUIPMENT & PROCEDURE CURVE TABLE
NC). DELTA RADIUS LENGTH
EQUIPMENT: LEICA 1' TOTAL STATION cl 570,00' 1677.35 148.83
AND CALIBRATED CHAIN
PROCEDURE: FIELD TRAVERSE
KOpp (LAZAKOWSKY)
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EASEUENT FOR INGRESS, SCALE:1 A1O0' PROFESSIONAL LAND SURVEYOR
PER VC)I.uME 2 OFF CHECKED BY: E.AND un E. 2680 AGATE RO. (206)426-4172
PER
z-I&-9S SURMIS PAGE oa S.C.B. Lf. SHELTON,WA. 98584
JOB #94-290
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R�148.776(CALC) L_148.83 (/PEC) J0.00
DECLARATION OF COVENANTS ASSOCIATED WITH
PRIVATELY MAINTAINED STORM DRAINAGE FACILITIES
Declaration of Covenant
In consideration of approval of the development known as
relating to real property legally described as follows:
The undersigned, as owner(s), covenant and agree that:
1. If at any time Mason County reasonably determines that maintenance or repair work is required
to be done to the existing, approved storm drainage facilities installed on the property described
above and located outside of any public right-of-way(which will mean repair and or clean out of the
existing system only to the same standards as originally installed and approved), the Director of the
Department of Public Works shall give the current owners seven days notice that the County intends
to perform such maintenance or repairs, or to have them performed by others.
If the current owners have not completed or are not diligently pursuing the repair or maintenance of
the system and it becomes necessary for Mason County to perform the work, the current owners will
assume responsibility for the cost of such maintenance or repair and will reimburse the County within
thirty days of receipt of the invoice. Overdue payments will require payment of interest at the current
legal rate for liquidated judgments, and any costs or fees incurred by the County, should any legal
action be required to collect such payments, will be borne by the parties responsible for said
reimbursements.
2. If at any time Mason County reasonably determines that the existing and approved storm drainage
system on the property poses a hazard to life and limb, or endangers property, or adversely affects
the safety and operations of a public way, due to failure, damage or non-maintenance of the existing
on-site storm system,and that the situation is so adverse as to preclude written notice to said owners,
the Director of the Department of Public Works may take the measures necessary to eliminate the
hazardous situation (which will mean repair or clean out of the existing system only to the same
standards as originally installed and approved) provided the Director has first made a reasonable
effort to locate said owner before acting.
The current owners will assume responsibility for the cost of such maintenance or repair; and will
reimburse the County within thirty days of receipt of the invoice. Overdue payments will require
payment of interest at the current legal rate for liquidated judgments, and any costs or fees incurred
by the County, should any be borne by the parties responsible for said reimbursements.
1 of 2
3. The owner shall keep the Mason County Public Works Department informed at all times as to the
name, address and telephone number of the contact person responsible for the performance of
maintenance or repair work to the storm drainage facilities.
These covenants are intended to protect the value and desirability of the real property described
above, and to benefit all the citizens of Mason County. They shall run with the land and be binding
on all parties having or acquiring from th
P g q g e current owners or their successors an right, title yor
interest therein, and to the benefit of all the citizens of Mason Count
y.
Signature Signature
Owner Owner
Address Address
City, State, Zip City, State, Zip
Phone: Phone:
STATE OF WASHINGTON,
County of MASON ss. (INDIVIDUAL ACKNOWLEDGEMENT)
I, ,Notary Public in and for the State of
Washington, residing at ,do hereby certify that on this day
of , 19 personally appeared before me
_to me known to be the individual_ described in and who executed the within instrument and
acknowledged that signed and sealed the same as free and voluntary act and
deed for the uses and purposes herein mentioned.
GIVEN UNDER MY HAND AND OFFICIAL SEAL this day of , 19
Notary Public in and for the State of Washington,
residing at in said County.
My Commission expires
2 of 2
Island West Assoc.
Catfish Area SSP
it
DESIGN DETAILS
of the
STORMWATER
and
EROSION CONTROL
PLAN
INTERIOR ROAD ONLY
Leffler Development Consuhants
Project#96-23
c:islandw1swc
Page , of 6
SUBJECT PROPERTY
Parcel It 321244 75 00140
305.715 234.19r
O rto
,
�r 1 . 2.1. AG. LOT 2 N
r 1 . 24 AC.
/ m \
1,
23.1.19
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�N 89'48'2.1` E 301.28
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1.= 146.17 (CAI_C) 1.= 146.83 (lax)
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71 Cr1USIiED SUHFACINO `' BALLAST I
t)' COMPACCnAVEL BASE) '
TED DEPTH (MIN :)' I R!J,TOP COUf13E � ��,
2' COMPACTED DEPTH COMPACTED (STADILIZED) SUDOIIADE �!
TYPICAL SECTION
ISLAND WEST ASSOC.
STORMWATER CONTROL PLAN
5.03 ACRES Sec. 34, T.21 N. R.3W., W.M.,
INTERIOR ROAD Project* 96-23
1,01ler DCVCItgrinalt Consultant
Pro.ied 11 96-23
MARLEY L. YOUNG ENGINEERS CERTIFICATE
CONSULTING CIVIL ENGINEER I HEREBY CERTIFY THAT THE
P.O. BOX 1 343 ENGINEERING SHOWN ON THIS � a
SHELTON. WA 96564 DRAWING WAS PERFORMED BY
(360)426-747-5 ME OR UNDER MY DIRECTION
* tit W
MAR*-EY L. OU PE-P DATE
[xwnu �y 98
Page 2 of 6
SHORT PLAT ROAD PLAN VIEW
PARCEL#32134 75 00140 6+75
LOT 1
'V' Ditch Design —6+00
vir
LOT 4 LOT 3 LOT 2
Flat Bottom
Special Ditch Design ii Ditch Design
Infiltration Trench Detention/Retention u`
'V' Ditch Design d Pond 'B' — 5+00
-� o Flat Bottom o �o
o Ditch Design N M
n.
U
g —4+00
Cn
�o� y 18" Diam. Culvert
\'VV" tch Design tUca�_ _ - - -- -- - - - - - - -
- - - - - - - - - - - - - - - - - - - - - - - - - - - - -
LOT 1LOT 15C - Natural Flow
0 50 100 Detention/Retention Pond 'A'
Scale Located in S.P. 2551 by Easement.
SHORT PLAT ROAD PROFILE
PARCEL#32134 75 00140
120 i .._.. - I -----I --+ -- —I---I--- a----I — --�---a -- -I ----4-- 120-
I I I I I I I I I I I I I I I I
115 I I I I I I I I I I I I I I I I
--- L---1--- 1 ---1---I---I--- I----I ---1---I---� -- I----i ---i---I---J 115
I I I I I I I I I I I I I I I I
I I I I I I I I I I I I I I I
110 I I I I I_ I I I _ II 1 I _ _ I _ I I 1110
_ _
I ► I 12.o,, o kl 2.00/
105 I 1 x'1' 1105
--- r---1--tgW. --fi----1---I-- — ----I---1— r--- --I-----I---I---1
100 I I I I I I I I I I I I I I 1100
-- F — ------}---{---DrTfNT"POND--4— — —{-Dff8 fiTIOWPONCH---�---i
I I I I I RIGI{T SIDEIOF ROAD I LEFt SIDE(�F ROAb I I
95 I I I I 1 I 1 20'X�� I I I 24'�12' II I I 195
I - - - J----- I -----I---I----I---� -- I -- I---I— —4--- — ---I---�----a
I I I I I I i 8"DIAM. CULVERT I I I I I I I
I I I I I I FIE ID LOCXTED I I I I I I
L-- --1-- —_L _J —1---L---1 -- ---1---1---1---J----1-- J---1---1 90
90
0+00 1+00 2+00 3+00 4+00 5+00 6+00 7+00
0 IS-DIAM.CULVERT
0 RETENTIONMETENTION POND
ISLAND WEST ASSOC.
STORMWATER CONTROL PLAN
5.03 ACRES Sec. 34, T.21 N. R.3W., W.M.,
I.elller lk-velcpmalt Consultant INTERIOR ROAD Project#96-23
Pruied#96-23'
MARLEY L. YOUNG rNGINEERS CERTIFICATE
CONSULTING CIVIL ENGINEER 1 HEREBY CERTIFY THAT THE
P.O. BOX 1 343 ENGINEERING SHOWN ON THIS
SHELTON. WA 98584 DRAWING WAS PERFORMED BY
(360)426-7475 ME OR UNDER MY DIRECTION + r A10
MARLEY L. lokmd tf.PILS 0 DATE-
0►
oo�o w
Page 3 of 6
Detention/Retention
Pond 'B' �4
5+00
O O k
O
N M
0
4+00
Natural
- - �r- - - - - - - - - - - - - - --=�"-A- - - - - - - -
�`- Natural Flow
0 50 100 Detention/Retention Pond 'A'
Scale Located in S. P. 2551 by Easement.
3:1 Side Slopes Top of berm
r6.0' 3:1 Side Slope Berm-Using mate
L..— 6.0' from pond
NATURAL GROUND 3:1 Side SIoF
t NATURAL GROUND 25'Min
IIEfIiEIIIEIREIIIEIIIEIffE1(fEHIIlE11IERfErItER1E111EfIlETllEfffEfll Elf�i . . - ---_. NATURAL GROUND
2.5' `�\EU IEIIIEIIIEIIIE I I IITE�1EIIiEIIlEI1)E111E1gE1nEEllf
2.0'Min. �IEInEInEnre roEmE�
3:1 Side Slopes F��'�e�, �
Fur BGM 3:1 Side Slope from floor
e to 3 feet above floor
POND 'A' FLOOR 20' X 71; MINIMUM DEPTH 2.5 FT.
POND 'B' FLOOR 24' X 1 2'; MINIMUM DEPTH 2.5 FT.
NOTE: Pond 'A'and'B' must have a floor
area of 288 sq.ft. and 140 sq.ft. respectively. TYPICAL DETENTION / RETENTION POND
The shape of the ponds or the widths and
lengths are less important than the floor areas. POND IAI AND POND IBl
SHOWING ALLOWABLE SIDE SLOPES
TYPICAL CROSS SECTION VIEW
3:1 Slope Bottom of Weir must be
_I 2.0' Min.above pond floor
6.00 "I Top of be
3:1 Slope 2.5'Mln above
above Pond Floor
Weir to be rocked with
Quarry Spales D50=0.25' 0 50'►I 1--- 0.29 Min.Weir Depth
Natural Ground --J
Natural Gound I--. Weir width
TYPICAL OVERFLOW WEIR
PONDS 'A' & 'B'
END VIEW
Top of berm --
0.511'Mln.Top o Sid,Slope 3:1
_ 2.0' From Pond Weir Fbw Llne to —6.0'
to Weir Fb Line erm
w Line � Top o1 B
Natural Ground
Quarry Spells D50= 25'
Slde Slope 3.1
Detention/Retention Pond Floor
TYPICAL OVERFLOW WEIR ISLAND WEST ASSOC.
PONDS IA' & 'B'SIDE VIEW STORMWATER CONTROL PLAN
'
5.03 ACRES Sec. 34, T.21N. R.3W., W.M.,
Leffler Dcvcic�pmpl.j Cixis INTERIOR ROAD Project# 96-23
I'rojed tl 96-2.3-23
MARLEY L. YOUNG ENGINEERS CF-19MEICATE
CONSULTING CIVIL ENGINEER I HEREBY CERTIFY THAT THE �O
P.O. BOX 1 343 ENGINEERING SHOWN ON THIS t fNi
SHELTON. WA 98584 DRAWING WAS PERFORMED BY 7 i 1-
(360)426-745 ME OR UNDER MY DIRECTION o P
MARL Et L. Y NO P PLS A—TE' 6�4p MA. 0
DcwRte I9g
Page 4 of 6
rn 0 0
+ +' Bottom of Ditch +
0 0
2.00--� �-+--
4.35
--2.0 --- 4.35
2.75
-- 14.60 �-
Bottom of Ditch r 7.00 --
i
DITCH LINE INFILTRATION POCKET
4 4.35 _-
75 l -. ..{ 7.00
TYPICAL DITCH LINE INFILTRATION POCKET
PROFILE VIEW
STATION 0+00 TO 1+00
BOTH ROADSIDE DITCHES
14.60' ---- - --- - .-I
Washed rock
2.00' __ 1-1/2 to 2-1/2 in. -- ` �—2.00'
I
Bottom of Ditch Lin
0000
CJ �p o p p�7 p 0p oa o Do 0
Odo�o� Cl
�0 7 00 0 0 0� 0 00 0
2.75+/- 7.0 Flat Bottom 4.35+/-
TYPICAL DITCH LINE INFILTRATION POCKET
SIDE VIEW DETAIL
- 1:1 Back of Ditch Slope
3:1 Ditch Slope
- Bottom of Ditch Line - Plat Roadway
- 1.0' Min.
o
ao
Washed rock o o
1-1/2 to 2-1/2 in 0
°0°a ° — -
a ooa040
OoOpdOao
DO 0000
Q 00 pO Q a
Vertical Side Slopes 00 ° 0 o 0 °° VARIBLE
��00
r,0 p 0 a
p a 0 bo Q o 2.75' to 4.35' +/-
°oaoOct
�+((5(A 0 <3 C�
3.4' Min. --►I
Flat Bottom
TYPICAL DITCH LINE INFILTRATION POCKET
END VIEW DETAIL
ISLAND WEST ASSOC.
STORMWATER CONTROL PLAN
5.03 ACRES Sec. 34, T.21 N. R.3W., W.M.,
INTERIOR ROAD Project# 96-23
I �Ill�r DevelovIneill Consultant
Proied // 96-23
MARLEY L. YOUNG ENGINEERS CERTIFICATE
CONSULTING CIVIL ENGINEER I HEREBY CERTIFY THAT THE Y�GyG,
P.O. BOX 1 343 ENGINEERING SHOWN ON THIS
SHELTON, WA 96594 DRAWING WAS PERFORMED BY z A
(360)426-7475 ME OR UNDER MY DIRECTION e� i
14 A 4
MARLEY L. E.
Page 5 of 6
ROADSIDE DITCH WITH WEIRS
FLAT BOTTOM DITCH 1 FOOT WIDE
Plat Roadway
Ditch Back Slope
1:1 Max. Ditch Slope 3:1 —
1.0' Min.
0.50'
o� 000 8 a oo�oo 0
on
Quarry Spales D50 = 0.25
1.0'
NOTE: Install Weirs in left ditch line at 25 ft.
C-C, between Sta.'s 1+00&3+50.
Weirs inTYPICAL DITCH WEIR InstaC-C Ilbetween Sta s right 41+50 tch & 5+75.line t ft
CROSS SECTIONAL VIEW
2:1 Slope
Quarry Spales D50 = 0.25
— 0.5'
e
Ditch Bottom - 1.01 3:1 Slope
Flow Line o°poo°L0 00
° °o
° 4x� Minus Grade
TYPICAL DITCH WEIR NOTE: Install Weirs in left ditch line at 25 ft.
PLAN VIEW C-C, between Sta.'s 1+00& 3+50.
Install Weirs in right ditch line at 15 ft
C-C, between Sta's 4+50 &5+75.
ISLAND WEST ASSOC.
STORMWATER CONTROL PLAN
5.03ACRES Sec. 34, T.21N. R.3W., W.M.,
Leffler Devoopment Consuhant INTERIOR ROAD Project# 96-23
Projed#i 96-23 '
MARLEY L. YOUNG ENGINEERS CERTIFICATE
CONSULTING CIVIL ENGINEER I HEREBY CERTIFY THAT THE OG
P-O. BOX 1 343 ENGINEERING SHOWN ON THIS �t
SHELTON. WA 98584 �do
(360)426-7475 DRAWING WAS PERFORMED BY
ME OR UNDER MY DIRECTION
MARPLS
�EY . Y UN O
iYoion ..,ne
Page 6 of 6
Vegetation -
Natural Ground
Edge of vegetation line
Use ditch spoils to create berm
Place berm of vegetation side of ditch
Plat Roadway :'..':` `'-'«.•-: ":r ;
— 1.00 minimum Ei11EIIlEIIlEIllEpl
II itt itt€ttt .ntf-lawEittut€it"EM
rr rr r 3:r � •,1 MPX
ROADSIDE DITCH
STATION 1+00 TO 3+20
RIGHT SIDE ONLY
-- Vegetation
_ Natural Ground
Edge of vegetation line
c
Use ditch spoils to create berm 1.0 Ft flat bottom ditch
Place berm of vegetation side of ditch
` • •,..,. �-- Plat Roadway
..... •: — 1.00 Min.
1EETi MEITIE11tElItEiIIE"IEAI ::: '``'
�T11Et1�iitEill�i(i�lir�l��'IIIEIIIEIIIEIIIEiIIp `
ernenr�nrenreurenreu e`.
ROADSIDE DITCH NOTE: PLACE WEIR IN DITCH
STATION 1+00 TO 3+50+/- 0.5' High and 25'Apart
LEFT SIDE ONLY
Vegetation
Natural Ground
Edge of vegetation line
1.0 Ft flat bottom ditch -
Use ditch spoils to create berm
Plat Roadway
Place berm of vegetation side of ditch
J
1.00 min.
edr�h --- IIEIIIEII �I I1�111 II II IIEIIIE III
M AX• pIE-tQ
ROADSIDE DITCH NOTE: PLACE WEIR IN DITCH
0.5' High and 15'Apart
STATION 4+00 TO 5+75
RIGHT SIDE ONLY
-- Vegetation
Natural Ground
Edge of vegetation line
Use ditch spoils to create berm
lace berm of vegetation side of ditch ` Plat Roadway
1.00 minimum \
IE111EITTEitiEMEnIL-"t€itttriti€ittlrlfftitF-MEttifitiEtttEiltEttiEtttEMEittEtttEHt-
rp f1p fp' J fur
Egreur M'�. 3:1 t tt EtttEtltE
ROADSIDE DITCH Enr�rrr
STATION 4+60 TO 6+75+/-
LEFT SIDE ONLY AND,
STATION 5+75 TO 6+75+/-
RIGHT SIDE ONLY
ISLAND WEST ASSOC.
STORMWATER CONTROL PLAN
5.03 ACRES Sec. 34, T.21N. R.3W., W.M.,
Prt�jed#1 6-
i etlicr ikvcll�m�xtt Cc # 96-23 INTERIOR ROAD Project# 96-23
MARLEY L. YOUNG EN91NEER5 CERTIFICATE
CONSULTING CIVIL ENGINEER I HERESY CERTIFY THAT THE ��Gy
P.O. BOX 1 343 ENGINEERING SHOWN ON TiiIS
SHELTON, WA 915564 DRAWING WAS PERFORMED BY r
(360)426-7475 ME OR UNDER MY DIRECTION
A, 144 W 4u
�1�.2�•9� o►ITI .+`A�
MARLEY L. N E.PLS DA;E MAL E 01 Y
W&I IV 95
STORM DRAINAGE " DESIGN ' NIANUAL
FIG 62
FILTER FABRIC MATERIAL 60' WIDE ROLLS
USE STAPLES OR WIRE RINGS TO ATTACH
FABRIC TO WIRE
2' x2' x14G0WIRE
FABRIC OR EOUIVILENT
2'0r
S'O'
F91
2'� BURY BOTTOM OF FILTER MATERIAL
IN 8" x 12' TRENCH
6' MAX
f x 4' WOOD POSTS, STANDARD OR BETTER
OR EQUAL ALTERNATE: STEEL FENCE POSTS
s
2' x 7 x 14 Go WIRE
FABRIC OR EOUN.
�o
FILTER FABRIC
MATERIAL
b
I iV
p�0 0
000
PROVIDE 3/4- TO .1-1/2'- 000
WASHED ROCK OR NATIVE Opp 5'Cl
BACKFILL ON BOTH SIDES 00
OF FILTER FABRIC FENCE 0 0
Op0
2' x 4' WOOD POST
ALT. STEEL FENCE POSTS
REFERENCE:
KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL
DATE:
FEB. 1991 FILTER FABRIC FENCE DETAIL
STORM DR AI\TAGE DESIG\T CI \U AL IFIG
SHEET FLOW
STAKES
BALES OF STRAW STAKED DOWN
PLAN
SINGLE ROW OF BALES OF STRAW TO BE
PLACED PRIOR TO THE START
OF ROUGH GRADING
COMPACTED SOIL TO
4' MIN PREVENT SLIPPING
FILTERED RUNOFF SEDIMENT LADEN
RUNOFF
i
IU�IEs I I I I-!I E= - T=m--11=1 I I
WEE!
NMI
B I I-1 11=1 1�l 11=11 I�1 f�11=1 11=1 11=
- 1=1 I��IEI1 I I I I 18 I I 11=111-:1 1 El 11=1 I
I EE�I E=-I I I-I I M 11=!i =1 I I-1 I,=1 11=1 11=1 I I I 1=1 I h ICi I i-I 11=!I i=1 I i=1 11=111-1 11=1 11=1 11=1 I C
.111=1 I IED I s I El 11=1 I IEE I iEl I I-I 1 I=-9 1 E 1 1=1 I El 11=1 11=:;I EE I El 11=i11E I El 11=1 I IE I F 11=
11=1 I IEE]I 1-=i I!-1 11=1 IEE]11=1 I FEI I I I I-1 11�1 8 i!=1 11=1 I a I a I 1=1 11=1 I C-I 11=1 11=1
it -
III-IIFIElII-IIIEIElII=IIIE]IaIE IE9IFIIIJI�IESIElII=IIIEI[=1I1=1II�IE lI
I E31�I 11=1 I a I C-I I!=i I IE3 I i3 11=1 I I-I I- I 11=1 I IE I B I I-11 I=_9 1 f=B I El 11=1 11=1 I I�I I_I I'
'=1 I I-I I a I El I I-I I I:-::]I F=I 11=1 I la I e 1�I I I-11 IE]I�I I I-I I►�I Iq I�I 11=1 II-"'-
''a I�I I(-I I la I El I!-1 I I�I B I I=1 i t=1 I Ia I a 11=1 I h 1 8 11=1 11�I L I El 11=!
=t I I CI I IE I IE3 1 EI 11=1 I I�I L 1 El 11=1 I I;I P'I'="'--'='-I II-
IgII=-I1-11��`
CROSS-SECTION OF A PROPERLY INSTALLED STRAW BALE
REFERENCE:
PUGET SOUND STORMWATER MANAGEMENT DRAFT
JDULY 1988 STRAW AND HAY BALE BARRIERS
Island West Assoc.
Catfish Area SSP
SUPPORTING
CALCULATIONS
Leffler Development Consultants
Project#96-23
c:lislandw3.swc
10/21/96 12: 31 :53 am Marley Young Engineer page 1
Island West Assoc.
S P/Catfish 3nd Sec Lt and Rt sides Pre
Stormwater Retention/Detention Pond
BASIN SUMMARY
BASIN ID: AAA NAME: 6 MO ROAD R/W 3ND SEC Lt side
SBUH METHODOLOGY
TOTAL AREA: . . . . . . : 0. 18 Acres BASEFLOWS: 0.00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 2 . 50 inches AREA. . : 0 . 18 Acres 0. 00 Acres
TIME INTERVAL. . . . : 2 . 00 min CN. . . . : 81 . 00 0 . 00
ABSTRACTION COEFF: 0. 20 TC. . . . : 28 .69 min 0 . 00 min
TcReach - Sheet L: 215.00 ns: 0. 4000 p2yr: 3 . 90 s: 0 . 0350
PEAK RATE: 0. 02 cfs VOL: 0. 00 Ac-ft TIME: 482 min
BASIN ID: AAAR NAME: 6 MO ROAD R/W 3ND SEC Rt side
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0. 17 Acres BASEFLOWS: 0. 00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 2.50 inches AREA. . : 0. 17 Acres 0. 00 Acres
TIME INTERVAL. . . . : 2 .00 min CN. . . . : 81 . 00 0 . 00
ABSTRACTION COEFF: 0. 20 TC. . . . : 28. 69 min 0. 00 min
TcReach - Sheet L: 215. 00 ns: 0. 4000 p2yr: 3 . 90 s:0 . 0350
PEAK RATE: 0 . 02 cfs VOL: 0.00 Ac-ft TIME: 482 min
BASIN ID: AAB NAME: 2 YR ROAD R/W 3rd Sec Lt side
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0. 18 Acres BASEFLOWS: 0 . 00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 3 . 95 inches AREA. . : 0 . 18 Acres 0 . 00 Acres
TIME INTERVAL. . . . : 2 . 00 min CN. . . . : 81 . 00 0 . 00
ABSTRACTION COEFF: 0 . 20 TC. . . . : 28 . 69 min 0.00 min
TcReach - Sheet L: 280 .00 ns: 0 . 4000 p2yr: 3 . 90 s: 0 .0300
PEAK RATE: 0. 06 cfs VOL: 0.01 Ac-ft TIME: 482 min
BASIN ID: AABR NAME: 2 YR ROAD R/W 3rd Sec Rt side
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0. 17 Acres BASEFLOWS: 0. 00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 3 . 95 inches AREA. . : 0.17 Acres 0 . 00 Acres
TIME INTERVAL. . . . : 2.00 min CN. . . . : 81 . 00 0. 00
ABSTRACTION COEFF: 0 . 20 TC. . . . : 28 . 69 min 0. 00 min
TcReach - Sheet L: 280. 00 ns:0 . 4000 p2yr: 3 . 90 s: 0 . 0300
PEAK RATE: 0. 06 cfs VOL: 0.01 Ac-ft TIME: 482 min
10/21/96 12: 31:54 am Marley Young Engineer page 2
Island West Assoc.
S P/Catfish 3nd Sec Lt and Rt sides Pre
Stormwater Retention/Detention Pond
BASIN SUMMARY
BASIN ID: AAC NAME: 10YR ROAD R/W 3rd SEC Lt Side
SBUH METHODOLOGY
TOTAL AREA.'. . . . . . : 0.18 Acres BASEFLOWS: 0. 00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 5.40 inches AREA. . : 0.18 Acres 0.00 Acres
TIME INTERVAL. . . . : 2.00 min CN. . . . : 81.00 0.00
TC. . . . : 28. 69 min 0. 00 min
ABSTRACTION COEFF: 0.20
TcReach - Sheet L: 280.00 ns:0.4000 p2yr: 3 .90 s:0.0300
PEAK RATE: 0.10 cfs VOL: 0.02 Ac-ft TIME: 480 min
BASIN ID: AACR NAME: 10YR ROAD R/W 3rd SEC Rt Side
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0.17 Acres BASEFLOWS: 0.00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 5.40 inches AREA. . : 0.17 Acres 0.00 Acres
TIME INTERVAL. . . . : 2.00 min CN. . . . : 81 .00 0.00
TC. . . . . 28.69 min 0. 00 min
ABSTRACTION COEFF: 0. 20
TcReach - Sheet L: 280. 00 ns:0.4000 p2yr: 3 .90 s:0.0300
PEAK RATE: 0. 10 cfs VOL: 0.02 Ac-ft TIME: 480 min
BASIN ID: AAD NAME: 100yr ROAD R/W 3rd SEC Lt side
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0.18 Acres BASEFLOWS: 0.00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 7.50 inches AREA. . : 0. 18 Acres 0.00 Acres
TIME INTERVAL. . . . : 2.00 min CN. . . . : 81.00 0.00
TC. . . . : 28.69 min 0.00 min
ABSTRACTION COEFF: 0.20
TcReach - Sheet L: 280.00 ns:0.4000 p2yr: 3 . 90 s:0.0300
PEAK RATE: 0.17 cfs VOL: 0.03 Ac-ft TIME: 480 min
BASIN ID: AADR NAME: 100yr ROAD R/W 3rd SEC Rt side
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0.17 Acres BASEFLOWS: 0. 00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 7.50 inches AREA. . : 0.17 Acres 0.00 Acres
TIME INTERVAL. . . . : 2.00 min CN. . . . : 81.00 0.00
TC. . . . . 28.69 min 0. 00 min
ABSTRACTION COEFF: 0.20
TcReach - Sheet L: 280.00 ns:0.4000 p2yr: 3 .90 s:0.0300
PEAK RATE: 0. 16 cfs VOL: 0.03 Ac-ft TIME: 480 min
10/21/96 12: 37:15 am Marley Young Engineer page 1
Island West Assoc.
S P/Catfish 3nd Sec Lt and Rt sides Pre
Stormwater Retention/Detention Pond
HYDROGRAPH SUMMARY
PEAK TIME VOLUME e
HYD RUNOFF OF OF Contrib
NUM RATE PEAK HYDRO Area
cfs min. cf\AcFt Acres
---------------------------------------------
4,44, 0.023 482 166 cf 0.18 �-
IA,O/ 2 0.061 482 469 cf 0.18
,44C 3 0. 104 480 844 cf 0.18
AA D 4 0.170 480 1454 cf 0. 18
0.021 482 155 cf 0.17 �«
,eQa/Z6 0.057 482 438 cf 0.17 n
,aCj7 0.097 480 787 cf 0.17
IL8 0.159 480 1357 cf 0.17 �r>TAL Q�'•_Ov�F�?,Ll
11 0.045 482 321 cf 0.35 = l + S a-v-"
12 0. 118 482 907 cf 0. 35
13 0. 201 480 1631 cf 0.35 = —�+-7
14 0. 329 480 2811 cf 0. 35 b
10/21/96 1: 38 :35 pm Marley Young Engineer page 1
Island West Assoc.
S P/Catfish 3nd Sec Rt sides Pre devel
Stormwater Retention/Detention Pond
BASIN SUMMARY
BASIN ID: AAa NAME: 6 MO ROAD R/W 3ND SEC Lt side
SBUH METHODOLOGY
TOTAL AREA:. . . . . . : 0.18 Acres BASEFLOWS: 0.00 cfs
RAINFALL TYPE. . . . : TYPElA PERV IMP
PRECIPITATION. . . . : 2 .50 inches AREA. . : 0.07 Acres 0.11 Acres
TIME INTERVAL. . . . : 2.00 min CN. . . . : 86.90 98.00
TC. . . . : 18. 69 min 18.69 min
ABSTRACTION COEFF: 0.20
TcReach - Sheet L: 215.00 ns:0.4000 p2yr: 3 . 90 s:0. 0350
PEAK RATE: 0.07 cfs VOL: 0.01 Ac-ft TIME: 480 min
BASIN ID: AAar NAME: 6 MO ROAD R/W 3ND SEC Rt side
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0.17 Acres BASEFLOWS: 0.00 cfs
RAINFALL TYPE. . . . : TYPElA PERV IMP
PRECIPITATION. . . . : 2. 50 inches AREA. . : 0. 09 Acres 0. 08 Acres
TIME INTERVAL. . . . : 2.00 min CN. . . . : 86.90 98.00
TC. . . . : 18.69 min 18. 69 min
ABSTRACTION COEFF: 0.20
TcReach - Sheet L: 215. 00 ns:0. 4000 p2yr: 3 .90 s:0.0350
PEAK RATE: 0.06 cfs VOL: 0.01 Ac-ft TIME: 480 min
BASIN ID: AAb NAME: 2YR ROAD R/W 3ND SEC Lt side
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0.18 Acres BASEFLOWS: 0.00 cfs
RAINFALL TYPE. . . . : TYPElA PERV IMP
PRECIPITATION. . . . : 3 .90 inches AREA. . : 0.07 Acres 0.11 Acres
TIME INTERVAL. . . . : 2.00 min CN. . . . : 86. 90 98.00
TC. . . . : 18.69 min 18.69 min
ABSTRACTION COEFF: 0.20
TcReach - Sheet L: 215.00 ns:0.4000 p2yr: 3 .90 s:0.0350
PEAK RATE: 0.12 cfs VOL: 0.02 Ac-ft TIME: 480 min
BASIN ID: AAbr NAME: 2YR ROAD R/W 3ND SEC Rt side
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0.17 Acres BASEFLOWS: 0.00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 0. 09 Acres 0.08 Acres
TIME INTERVAL. . . . : 2.00 min CN. . . . : 86.90 98 .00
TC. . . . : 18.69 min 18.69 min
ABSTRACTION COEFF: 0.20
TcReach - Sheet L: 215.00 ns:0.4000 p2yr: 3 . 90 s:0. 0350
PEAK RATE: 0.10 cfs VOL: 0.02 Ac-ft TIME: 480 min
10/21/96 1 :38: 35 pm Marley Young Engineer page 2
Island West Assoc.
S P/Catfish 3nd Sec Rt sides Pre devel
Stormwater Retention/Detention Pond
BASIN SUMMARY
BASIN ID: AAc NAME: 10yr ROAD R/W 3ND SEC Lt side
SBUH METHODOLOGY
TOTAL AREA: . . . . . . : 0. 18 Acres BASEFLOWS: 0. 00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 5.40 inches AREA. . : 0. 07 Acres 0. 11 Acres
TIME INTERVAL. . . . : 2 . 00 min CN. . . . : 86 .90 98. 00
TC. . . . : 18 . 69 min 18. 69 min
ABSTRACTION COEFF: 0. 20
TcReach - Sheet L: 215. 00 ns:0. 4000 p2yr: 3 . 90 s:0. 0350
PEAK RATE: 0. 17 cfs VOL: 0. 04 Ac-ft TIME: 480 min
BASIN ID: AAcr
NAME: 10 r ROAD R W 3ND SEC Rt• Y / side
SBUH METHODO
LOGY
TOTAL AREA. . . . . . . : 0. 17 Acres BASEFLOWS: 0 . 00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 5. 40 inches AREA. . : 0. 09 Acres 0. 08 Acres
TIME INTERVAL. . . . : 2 . 00 min CN. . . . : 86. 90 98. 00
TC. . . . . 18 . 69 min 18 . 69 min
ABSTRACTION COEFF: 0. 20
TcReach - Sheet L: 215. 00 ns: 0 . 4000 p2yr: 3 . 90 s:0. 0350
PEAK RATE: 0 . 15 cfs VOL: 0. 03 Ac-ft TIME: 480 min
BASIN ID: AAd NAME: i
100 r ROAD R W 3ND SEC Lt s
Y / de
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0. 18 Acres BASEFLOWS: 0.00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 7 .50 inches AREA. . : 0. 07 Acres 0. 11 Acres
TIME INTERVAL. . . . : 2 . 00 min CN. . . . : 86 . 90 98 . 00
TC. . . . . 18 . 69 min 18 . 69 min
ABSTRACTION COEFF: 0 . 20
TcReach - Sheet L: 215. 00 ns: 0 . 4000 p2yr: 3 . 90 s: 0 . 0350
PEAK RATE: 0 . -
24 cfs VOL: 0.05 Ac ft TIME: 480 mi• n
BASIN ID: AAdr NAME: /
ROAD 100Y r R W 3ND SEC RT sid
e
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0. 17 Acres BASEFLOWS: 0. 00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 7. 50 inches AREA. . : 0 . 09 Acres 0 . 08 Acres
TIME INTERVAL. . . . : 2 . 00 min CN. . . . : 86 . 90 98 . 00
ABSTRACTION COEFF: 0 . 20 TC. . . . : 18. 69 min 18 . 69 min
TcReach - Sheet L: 215. 00 ns: 0. 4000 p2yr: 3 . 90 s: 0. 0350
PEAK RATE: 0 . 22 cfs VOL: 0 .05 Ac-ft TIME: 480 min
10/21/96 1:22:55 pm Marley Young Engineer page 1
Island West Assoc.
S P/Catfish 3nd Sec Lt & Rt sides POST
Stormwater Retention/Detention Pond
HYDROGRAPH SUMMARY
PEAK TIME VOLUME
HYD RUNOFF OF OF Contrib
NUM RATE PEAK HYDRO Area
cfs min. cf\AcFt Acres
1 0.068 480 593 cf 0.18 �r
2 0.116 480 1053 cf 0. 181-r
3 0.168 480 1569 cf 0.18ti T
d 4 0.242 480 2309 cf 0. 18 c ,-
a'(L 5 0.058 480 498 cf 0 . 17 kT
{o'2 6 0. 103 480 910 cf 0. 17 LT
CE7 0. 152 480 1379 cf 0.17 /T n
d $ 0.221 480 2058 cf 0. 17z7-
A
,4 G c:c rl ':` ✓rw .r o-� a
1.; o
n
10/21/96 1: 38: 35 pm Marley Young Engineer page 3
Island West Assoc.
S P/Catfish and Sec Rt sides Pre devel
Stormwater Retention/Detention Pond
HYDROGRAPH SUMMARY
PEAK TIME VOLUME
HYD RUNOFF OF OF Contrib
NUM RATE PEAK HYDRO Area
cfs min. cf\AcFt Acres
1 0.068 480 593 cf 0.18 Z-7-
2 0.116 480 1053 cf 0.18 /-- T
3 0.168 480 1569 cf 0. 18 7-
4 0.242 480 2309 cf 0.18 -/- 7-
5 0.058 480 498 cf 0. 17 2 T
6 0.103 480 910 cf 0.17 Z7-
7 0.152 480 1379 cf 0.17 Q.7-
8 0.221 480 2058 cf 0. 17 i2 T
9 0.056 486 431 cf 0.17
10 0.100 484 835 cf 0.17
11 0.148 484 1297 cf 0. 17
12 0 . 216 484 1966 cf 0.17
13 0.044 486 237 cf 0.00—C2t-k
14 0.087 484 576 cf 0.00 _
15 0.135 484 997 cf 0.00
16 0. 202 484 1632 cf 0.00-- T
17 0.012 486 195 cf 0.00
18 0.013 484 259 cf 0.00
19 0.013 484 300 cf 0.00
20 0.014 484 335 cf 0 .00
lLco f'�iL� 1�•rcr L— /per ��ry D� 171SC1-rA2coL;
7
v o�d LA-)
10/21/96 1: 38: 36 pm Marley Young Engineer page 4
Island West Assoc.
S P/Catfish 3nd Sec Rt sides Pre devel
Stormwater Retention/Detention Pond
STAGE STORAGE TABLE
TRAPEZOIDAL BASIN ID No. 3drt
Description: 3 Sec Right Ditch Free flow
Length: 125.00 ft. Width: 1.00 ft.
Side Slope 1: 3 Side Slope 3 : 0
Side Slope 2: 3 Side Slope 4: 0
Infiltration Rate: 45.00 min/inch
STAGE <----STORAGE----> STAGE <----STORAGE----> STAGE <----STORAGE----> STAGE <----STORAGE---->
(ft) ---cf--- --Ac-Ft- (ft) ---cf--- --Ac-Ft- (ft) ---cf--- --Ac-Ft- (ft) ---cf--- --Ac-Ft-
100.00 0.0000 0.0000 100.26 57.850 0.0013 100.52 166.40 0.0038 100.78 325.65 0.0075
100.02 2.6500 0.0001 100.28 64.400 0.0015 100.54 176.85 0.0041 100.80 340.00 0.0078
100.04 5.6000 0.0001 100.30 71.250 0.0016 100.56 187.60 0.0043 100.82 354.65 0.0081
100.06 8.8500 0.0002 100.32 78.400 0.0018 100.58 198.65 0.0046 100.84 369.60 0.0085
100.08 12.400 0.0003 100.34 85.850 0.0020 100.60 210.00 0.0048 100.86 384.85 0.0088
100.10 16.250 0.0004 100.36 93.600 0.0021 100.62 221.65 0.0051 100.88 400.40 0.0092
100.12 20.400 0.0005 100.38 101.65 0.0023 100.64 233.60 0.0054 100.90 416.25 0.0096
100.14 24.850 0.0006 100.40 110.00 0.0025 100.66 245.85 0.0056 100.92 432.40 0.0099
100.16 29.600 0.0007 100.42 118.65 0.0027 100.68 258.40 0.0059 100.94 448.85 0.0103
100.18 34.650 0.0008 100.44 127.60 0.0029 100.70 271.25 0.0062 100.96 465.60 0.0107
100.20 40.000 0.0009 100.46 136.85 0.0031 100.72 284.40 0.0065 100.98 482.65 0.0111
100.22 45.650 0.0010 100.48 146.40 0.0034 100.74 297.85 0.0068 101.00 500.00 0.0115
100.24 51.600 0.0012 100.50 156.25 0.0036 100.76 311.60 0.0072
10/21/96 1 : 38: 36 pm Marley Young Engineer page 5
Island West Assoc.
S P/Catfish 3nd Sec Rt sides Pre devel
Stormwater Retention/Detention Pond
STAGE STORAGE TABLE
Infiltration Rating Curve for Storage Struct 3drt
STAGE <-INFILTRATION-> STAGE <-INFILTRATION-> STAGE <-INFILTRATION-> STAGE <-INFILTRATION->
(ft) ---cfS-- ------- (ft) ---cfS-- ------- (ft) ---cfS-- ------- (ft) ---cfS-- -------
----------------
100.00 0.0039 100.26 0.0102 100.52 0.0166 100.78 0.0231
100.02 0.0043 100.28 0.0107 100.54 0.0171 100.80 0.0235
100.04 0.0048 100.30 0.0112 100.56 0.0176 100.82 0.0240
100.06 0.0053 100.32 0.0117 100.58 0.0181 100.84 0.0245
100.08 0.0058 100.34 0.0122 100.60 0.0186 100.86 0.0250
100.10 0.0063 100.36 0.0127 100.62 0.0191 100.88 0.0255
100.12 0.0068 100.38 0.0132 100.64 0.0196 100.90 0.0260
100.14 0.0073 100.40 0.0137 100.66 0.0201 100.92 0.0265
100.16 0.0078 100.42 0.0142 100.68 0.0206 100.94 0.0270
100.18 0.0083 100.44 0.0147 100.70 0.0211 100.96 0.0275
100.20 0.0088 100.46 0.0151 100.72 0.0216 100.98 0.0280
100.22 0.0092 100.48 0.0156 100.74 0.0221 101.00 0.0285
100.24 0.0097 100.50 0.0161 100.76 0.0226
10/21/96 1:38: 36 pm Marley Young Engineer page 6
Island West Assoc.
S P/Catfish 3nd Sec Rt sides Pre devel
Stormwater Retention/Detention Pond
STAGE DISCHARGE TABLE
BROAD CRESTED WEIR ID No. z
Description:
cd: 3 . 2100 ' Weir length: 0.5000 ft.
El: 100.25 ft. Weir Increm: 0.02
STAGE <--DISCHARGE---> STAGE <--DISCHARGE---> STAGE <--DISCHARGE---> STAGE <--DISCHARGE--->
(ft) ---CfS-- ------- (ft) ---cfS-- ------- (ft) ---cfS-- ------- (ft) ---cfS-- -------
------------------
100.25 0.0000 100.32 0.0397 100.40 0.1604 100.48 0.3725
100.26 0.0017 100.34 0.0621 100.42 0.2043 100.50 0.4414
100.28 0.0095 100.36 0.0895 100.44 0.2542
100.30 0.0223 100.38 0.1222 100.46 0.3101
10/21/96 1: 38:37 pm Marley Young Engineer page 7
Island West Assoc.
S P/Catfish 3nd Sec Rt sides Pre devel
Stormwater Retention/Detention Pond
LEVEL POOL TABLE SUMMARY
MATCH INFLOW -STO- -DIS- <-PEAK-> STORAGE
<--------DESCRIPTION---------> (cfs) (cfs) --id- --id- <-STAGE> id VOL (cf) L
_____________________________________________________________________ �� H
6 month storm event .......... 0.06 0.06 3drt z 100.32 9 79.77 cf
2 year storm event ........... 0.10 0.10 3drt z 100.36 10 92.92 cf
10 year storm event .......... 0.15 0.15 3drt z 100.39 11 104.49 cf
100 year storm event ......... 0.22 0.22 3drt z 100.42 12 118.25 cf
I
10/21/96 2 : 6 : 4 pm Marley Young Engineer page 1
Island West Assoc.
S P/Catfish 3nd Sec Lt sides Post Develo
Stormwater Retention/Detention Pond
BASIN SUMMARY
BASIN ID: AAa NAME: 6 MO ROAD R/W 3ND SEC Lt side
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0 . 18 Acres BASEFLOWS: 0 . 00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 2 .50 inches AREA. . : 0 . 07 Acres 0 . 11 Acres
TIME INTERVAL. . . . : 2 . 00 min CN. . . . : 86 . 90 98 . 00
TC. . . . : 18 . 69 min 18 . 69 min
ABSTRACTION COEFF: 0. 20
TcReach - Sheet L: 215 . 00 ns: 0 . 4000 p2yr: 3 . 90 s: 0. 0350
PEAK RATE: 0 . 07 cfs VOL: 0. 01 Ac-ft TIME: 480 min
BASIN ID: AAar NAME: 6 MO ROAD R/W 3ND SEC Rt side
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0. 17 Acres BASEFLOWS: 0. 00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 2 . 50 inches AREA. . : 0 . 09 Acres 0 . 08 Acres
TIME INTERVAL. . . . : 2 . 00 min CN. . . . : 86 . 90 98 . 00
TC. . . . : 18. 69 min 18 . 69 min
ABSTRACTION COEFF: 0 . 20
TcReach - Sheet L: 215. 00 ns:0. 4000 p2yr: 3 . 90 s: 0. 0350
PEAK RATE: 0 . 06 cfs VOL: 0. 01 Ac-ft TIME: 480 min
BASIN ID: AAb NAME: 2YR ROAD R/W 3ND SEC Lt side
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0. 18 Acres BASEFLOWS: 0 . 00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 0 . 07 Acres 0 . 11 Acres
TIME INTERVAL. . . . : 2 . 00 min CN. . . . : 86 . 90 98 . 00
TC. . . . : 18 . 69 min 18 . 69 min
ABSTRACTION COEFF: 0 . 20
TcReach - Sheet L: 215. 00 ns:0. 4000 p2yr: 3 . 90 s:0 . 0350
PEAK RATE: 0 . 12 cfs VOL: 0 . 02 Ac-ft TIME: 480 min
BASIN ID: AAbr NAME: 2YR ROAD R/W 3ND SEC Rt side
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0 . 17 Acres BASEFLOWS: 0 . 00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 0 . 09 Acres 0.08 Acres
TIME INTERVAL. . . . : 2 . 00 min CN. . . . : 86. 90 98 .00
TC. . . . : 18 . 69 min 18 . 69 min
ABSTRACTION COEFF: 0. 20
TcReach - Sheet L: 215.00 ns:0 .4000 p2yr: 3. 90 s:0 . 0350
PEAK RATE: 0 . 10 cfs VOL: 0 . 02 Ac-ft TIME: 480 min
10/21/96 2 : 6 : 5 pm Marley Young Engineer page 2
Island West Assoc.
S P/Catfish 3nd Sec Lt sides Post Develo
Stormwater Retention/Detention Pond
BASIN SUMMARY
BASIN ID: AAc NAME: 10yr ROAD R/W 3ND SEC Lt side
SBUH METHODOLOGY
TOTAL AREA.. . . . . . : 0. 18 Acres BASEFLOWS: 0 . 00 cf
s
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 5.40 inches AREA. . : 0 . 07 Acres 0. 11 Acres
TIME INTERVAL. . . . : 2 . 00 min CN. . . . : 86 . 90 98 . 00
TC. . . . : 18 . 69 min 18 . 69 min
ABSTRACTION COEFF: 0. 20
TcReach - Sheet L: 215. 00 ns: 0 .4000 p2yr: 3 . 90 s: 0 . 0350
PEAK RATE: 0 . 17 cfs VOL: 0 . 04 Ac-ft TIME: 480 min
BASIN ID: AAcr NAME: 10yr ROAD R/W 3ND SEC Rt side
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0. 17 Acres BASEFLOWS: 0 . 00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 5. 40 inches AREA. . : 0. 09 Acres 0 . 08 Acres
TIME INTERVAL. . . . : 2 . 00 min CN. . . . : 86 . 90 98 . 00
TC. . . . : 18 . 69 min 18 . 69 min
ABSTRACTION COEFF: 0. 20
TcReach - Sheet L: 215. 00 ns: 0. 4000 p2yr: 3 . 90 s: 0 . 0350
PEAK RATE: 0 . 15 cfs VOL: 0 . 03 Ac-ft TIME: 480 min
BASIN ID: AAd NAME: 100yr ROAD R/W 3ND SEC Lt side
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0 . 18 Acres BASEFLOWS: 0 . 00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 7. 50 inches AREA. . : 0 . 07 Acres 0 . 11 Acres
TIME INTERVAL. . . . : 2 . 00 min CN. . . . : 86 . 90 98 . 00
TC. . . . : 18 . 69 min 18 . 69 min
ABSTRACTION COEFF: 0. 20
TcReach - Sheet L: 215 . 00 ns:0. 4000 p2yr: 3 . 90 s : 0. 0350
PEAK RATE: 0 . 24 cfs VOL: 0 . 05 Ac-ft TIME: 480 min
BASIN ID: AAdr NAME: 100yr ROAD R/W 3ND SEC RT side
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0. 17 Acres BASEFLOWS: 0. 00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 7 . 50 inches AREA. . : 0. 09 Acres 0 . 08 Acres
TIME INTERVAL. . . . : 2 . 00 min CN. . . . : 86 . 90 98 .00
ABSTRACTION COEFF: 0. 20 TC. . . . : 18 . 69 min 18. 69 min
TcReach - Sheet L: 215. 00 ns:0. 4000 p2yr: 3 . 90 s: 0. 0350
PEAK RATE: 0. 22 cfs VOL: 0 . 05 Ac-ft TIME: 480 min
10/21/96 2:6:5 pm Marley Young Engineer page 3
Island West Assoc.
S P/Catfish 3nd Sec Lt sides Post Develo
Stormwater Retention/Detention Pond
HYDROGRAPH SUMMARY
PEAK TIME VOLUME
HYD RUNOFF OF OF Contrib
NUM RATE PEAK HYDRO Area
cfs min. cf\AcFt Acres
1 0.068 480 593 cf 0. 18
2 0.116 480 1053 cf 0 . 18
3 0.168 480 1569 cf 0.18
4 0.242 480 2309 cf 0.18
5 0. 058 480 498 cf 0.17
6 0.103 480 910 cf 0. 17
7 0.152 480 1379 cf 0.17
8 0. 221 480 2058 cf 0. 17
9 0.015 600 285 cf 0. 18
10 0.021 600 387 cf 0.18
11 0.027 600 481 cf 0.18
12 0.149 510 1128 cf 0. 18
16 0.119 510 551 cf 0.00
17 0.015 600 285 cf 0. 00
18 0. 021 600 387 cf 0.00
19 0.027 600 481 cf 0.00
20 0. 029 510 576 cf 0. 00
Ny.�
/q
6 !�
10/21/96 2:6:5 pm Marley Young Engineer page 4
Island West Assoc.
S P/Catfish 3nd Sec Lt sides Post Develo
Stormwater Retention/Detention Pond
STAGE STORAGE TABLE
TRAPEZOIDAL BASIN ID No. s
Description: Pond at
Length: '24.00 ft. Width: 12 .00 ft.
Side Slope 1: 3 Side Slope 3 : 3
Side Slope 2: 3 Side Slope 4: 3
Infiltration Rate: 45. 00 min/inch
STAGE <----STORAGE----> STAGE <----STORAGE----> STAGE <----STORAGE----> STAGE <----STORAGE---->
(ft) ---cf--- --Ac-Ft- (ft) ---cf--- --Ac-Ft- (ft) ---cf--- --Ac-Ft- (ft) ---cf--- --Ac-Ft-
100.00 0.0000 0.0000 100.64 231.70 0.0053 101.28 570.75 0.0131 101.92 1036 0.0238
100.02 5.8033 0.0001 100.66 240.57 0.0055 101.30 583.28 0.0134 101.94 1053 0.0242
100.04 11.694 0.0003 100.68 249.55 0.0057 101.32 595.94 0.0137 101.96 1070 0.0246
100.06 17.671 0.0004 100.70 258.64 0.0059 101.34 608.72 0.0140 101.98 1087 0.0249
100.08 23.737 0.0005 100.72 267.83 0.0061 101.36 621.62 0.0143 102.00 1104 0.0253
100.10 29.892 0.0007 100.74 277.12 0.0064 101.38 634.65 0.0146 102.02 1121 0.0257
100.12 36.136 0.0008 100.76 286.53 0.0066 101.40 647.81 0.0149 102.04 1139 0.0261
100.14 42.470 0.0010 100.78 296.04 0.0068 101.42 661.09 0.0152 102.06 1156 0.0265
100.16 48.894 0.0011 100.80 305.66 0.0070 101.44 674.50 0.0155 102.08 1174 0.0270
100.18 55.409 0.0013 100.82 315.40 0.0072 101.46 688.04 0.0158 102.10 1192 0.0274
100.20 62.016 0.0014 100.84 325.24 0.0075 101.48 701.70 0.0161 102.12 1210 0.0278
100.22 68.715 0.0016 100.86 335.19 0.0077 101.50 715.50 0.0164 102.14 1229 0.0282
100.24 75.507 0.0017 100.88 345.25 0.0079 101.52 729.42 0.0167 102.16 1247 0.0286
100.26 82.392 0.0019 100.90 355.43 0.0082 101.54 743.48 0.0171 102.18 1265 0.0291
100.28 89.371 0.0021 100.92 365.72 0.0084 101.56 757.67 0.0174 102.20 1284 0.0295
100.30 96.444 0.0022 100.94 376.12 0.0086 101.58 771.98 0.0177 102.22 1303 0.0299
100.32 103.61 0.0024 100.96 386.63 0.0089 101.60 786.43 0.0181 102.24 1322 0.0303
100.34 110.88 0.0025 100.98 397.26 0.0091 101.62 801.01 0.0184 102.26 1341 0.0308
100.36 118.24 0.0027 101.00 408.00 0.0094 101.64 815.73 0.0187 102.28 1360 0.0312
100.38 125.69 0.0029 101.02 418.86 0.0096 101.66 830.58 0.0191 102.30 1380 0.0317
100.40 133.25 0.0031 101.04 429.83 0.0099 101.68 845.56 0.0194 102.32 1399 0.0321
100.42 140.90 0.0032 101.06 440.92 0.0101 101.70 860.68 0.0198 102.34 1419 0.0326
100.44 148.65 0.0034 101.08 452.13 0.0104 101.72 875.93 0.0201 102.36 1439 0.0330
100.46 156.50 0.0036 101.10 463.45 0.0106 101.74 891.32 0.0205 102.38 1459 0.0335
100.48 164.45 0.0038 101.12 474.89 0.0109 101.76 906.84 0.0208 102.40 1479 0.0340
100.50 172.50 0.0040 101.14 486.46 0.0112 101.78 922.50 0.0212 102.42 1500 0.0344
100.52 180.65 0.0041 101.16 498.14 0.0114 101.80 938.30 0.0215 102.44 1520 0.0349
100.54 188.90 0.0043 101.18 509.94 0.0117 101.82 954.24 0.0219 102.46 1541 0.0354
100.56 197.26 0.0045 101.20 521.86 0.0120 101.84 970.32 0.0223 102.48 1562 0.0358
100.58 205.71 0.0047 101.22 533.90 0.0123 101.86 986.54 0.0226 102.50 1583 0.0363
100.60 214.27 0.0049 101.24 546.06 0.0125 101.88 1003 0.0230
100.62 222.94 0.0051 101.26 558.35 0.0128 101.90 1019 0.0234
10/21/96 2 :6:5 pm Marley Young Engineer page 5
Island West Assoc.
S P/Catfish 3nd Sec Lt sides Post Develo
Stormwater Retention/Detention Pond
---------------------------------------------------------------------
----------------------------------------------
STAGE STORAGE TABLE
Infiltration Rating Curve for Storage Struct s
STAGE <-INFILTRATION-> STAGE <-INFILTRATION-> STAGE <-INFILTRATION-> STAGE <-INFILTRATION->
(ft) ---cfs-- ------- (ft) ---cfs-- ------- (ft) ---cfs-- ------- (ft) ---cfs-- -------
-------------
100.00 0.0089 100.64 0.0139 101.28 0.0198 101.92 0.0267
100.02 0.0090 100.66 0.0140 101.30 0.0200 101.94 0.0269
100.04 0.0092 100.68 0.0142 101.32 0.0202 101.96 0.0272
100.06 0.0093 100.70 0.0144 101.34 0.0204 101.98 0.0274
100.08 0.0095 100.72 0.0146 101.36 0.0206 102.00 0.0276
100.10 0.0096 100.74 0.0147 101.38 0.0208 102.02 0.0279
100.12 0.0097 100.76 0.0149 101.40 0.0210 102.04 0.0281
100.14 0.0099 100.78 0.0151 101.42 0.0212 102.06 0.0283
100.16 0.0100 100.80 0.0153 101.44 0.0214 102.08 0.0286
100.18 0.0102 100.82 0.0154 101.46 0.0216 102.10 0.0288
100.20 0.0103 100.84 0.0156 101.48 0.0219 102.12 0.0291
100.22 0.0105 100.86 0.0158 101.50 0.0221 102.14 0.0293
100.24 0.0106 100.88 0.0160 101.52 0.0223 102.16 0.0295
100.26 0.0108 100.90 0.0162 101.54 0.0225 102.18 0.0298
100.28 0.0109 100.92 0.0163 101.56 0.0227 102.20 0.0300
100.30 0.0111 100.94 0.0165 101.58 0.0229 102.22 0.0303
100.32 0.0113 100.96 0.0167 101.60 0.0231 102.24 0.0305
100.34 0.0114 100.98 0.0169 101.62 0.0233 102.26 0.0308
100.36 0.0116 101.00 0.0171 101.64 0.0236 102.28 0.0310
100.38 0.0117 101.02 0.0173 101.66 0.0238 102.30 0.0312
100.40 0.0119 101.04 0.0175 101.68 0.0240 102.32 0.0315
100.42 0.0120 101.06 0.0177 101.70 0.0242 102.34 0.0317
100.44 0.0122 101.08 0.0178 101.72 0.0244 102.36 0.0320
100.46 0.0124 101.10 0.0180 101.74 0.0247 102.38 0.0322
100.48 0.0125 101.12 0.0182 101.76 0.0249 102.40 0.0325
100.50 0.0127 101.14 0.0184 101.78 0.0251 102.42 0.0328
100.52 0.0129 101.16 0.0186 101.80 0.0253 102.44 0.0330
100.54 0.0130 101.18 0.0188 101.82 0.0256 102.46 0.0333
100.56 0.0132 101.20 0.0190 101.84 0.0258 102.48 0.0335
100.58 0.0134 101.22 0.0192 101.86 0.0260 102.50 0.0338
100.60 0.0135 101.24 0.0194 101.88 0.0262
100.62 0.0137 101.26 0.0196 101.90 0.0265
10/21/96 2:6:6 pm Marley Young Engineer page 6
Island West Assoc.
S P/Catfish 3nd Sec Lt sides Post Develo
Stormwater Retention/Detention Pond
STAGE DISCHARGE TABLE
BROAD CRESTED WEIR ID No. w
Description:
cd: 3 . 2100 ' Weir length: 0.5000 ft.
El: 102.00 ft. Weir Increm: 0.02
STAGE <--DISCHARGE---> STAGE <--DISCHARGE---> STAGE <--DISCHARGE---> STAGE <--DISCHARGE--->
(ft) ---CfS-- ------- (ft) ---CfS-- ------- (ft) ---CfS-- ------- (ft) ---CfS-- -------
-----------------------------------
102.00 0.0000 102.14 0.1406 102.28 0.5574 102.42 1.3176
102.02 0.0050 102.16 0.1816 102.30 0.6435 102.44 1.4578
102.04 0.0153 102.18 0.2285 102.32 0.7368 102.46 1.6064
102.06 0.0304 102.20 0.2814 102.34 0.8375 102.48 1.7635
102.08 0.0503 102.22 0.3405 102.36 0.9457 102.50 1.9293
102.10 0.0751 102.24 0.4061 102.38 1.0617
102.12 0.1051 102.26 0.4783 102.40 1.1856
10/21/96 2:6: 23 pm Marley Young Engineer page 7
Island West Assoc.
S P/Catfish 3nd Sec Lt sides Post Develo
Stormwater Retention/Detention Pond
LEVEL POOL TABLE SUMMARY
MATCH INFLOW -STO- -DIS- <-PEAR-> STORAGE
<--------DESCRIPTION---------> (cfs) (cfs) --id- --id- <-STAGE> id VOL (cf)
6 month storm event .......... 0.07 0.07 s w 100.80 9 304.73 cf
2 year storm event ........... 0.12 0.12 s w 101.42 10 660.33 cf
10 year storm event .......... 0.17 0.17 s w 101.97 11 1079.64 cf
100 year storm event ......... 0.24 0.24 s w 102.13 12 1217.60 cf
10/21/96 11:1 :52 am Marley Young Engineer page 1
Island West Assoc.
Short Plat in Catfish 2nd Section
Stormwater Retention/Detention Pond
BASIN SUMMARY
BASIN ID: AA NAME: 6 MO ROAD R/W 2ND SEC Lt side
SBUH METHODOLOGY
TOTAL AREA: . . . . . . : 0. 16 Acres BASEFLOWS: 0 . 00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 2 .50 inches AREA. . : 0 . 16 Acres 0. 00 Acres
TIME INTERVAL. . . . : 5. 00 min CN. . . . : 81 . 00 0 . 00
TC. . . . : 29 . 18 min 0.00 min
ABSTRACTION COEFF: 0. 20
TcReach - Sheet L: 240. 00 ns: 0 . 4000 p2yr: 3 . 90 s: 0. 0200
PEAK RATE: 0 . 02 cfs VOL: 0. 01 Ac-ft TIME: 485 min
BASIN ID: AAR NAME: 6 MO ROAD R/W 2ND SEC Rt side
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0. 12 Acres BASEFLOWS: 0 . 00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 2 . 50 inches AREA. . : 0.12 Acres 0 . 00 Acres
TIME INTERVAL. . . . : 5. 00 min CN. . . . : 81 . 00 0 . 00
TC. . . . . 29 . 18 min 0 . 00 min
ABSTRACTION COEFF: 0. 20
TcReach - Sheet L: 240 .00 ns: 0 . 4000 p2yr: 3 . 90 s: 0 . 0200
PEAK RATE: 0.01 cfs VOL: 0. 01 Ac-ft TIME: 485 min
BASIN ID: AB NAME: 2 YR ROAD R/W 2ND SEC Lt Side
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0. 16 Acres BASEFLOWS: 0. 00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 3 . 95 inches AREA. . : 0. 16 Acres 0. 00 Acres
TIME INTERVAL. . . . : 5. 00 min CN. . . . : 81. 00 0 . 00
TC. . . . : 29. 18 min 0 . 00 min
ABSTRACTION COEFF: 0. 20
TcReach - Sheet L: 280. 00 ns: 0 . 4000 p2yr: 3 . 90 s: 0. 0300
PEAK RATE: 0 .05 cfs VOL: 0.03 Ac-ft TIME: 485 min
BASIN ID: ABR NAME: 2 YR ROAD R/W 2ND SEC Rt Side
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0 . 12 Acres BASEFLOWS: 0 . 00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 3 . 95 inches AREA. . : 0 .12 Acres 0 . 00 Acres
TIME INTERVAL. . . . : 5. 00 min CN. . . . : 81 . 00 0. 00
TC. . . . . 29. 18 min 0 . 00 min
ABSTRACTION COEFF: 0. 20
TcReach - Sheet L: 280 . 00 ns: 0. 4000 p2yr: 3 . 90 s:0 . 0300
PEAK RATE: 0. 04 cfs VOL: 0 .02 Ac-ft TIME: 485 min
10/21/96 11 :1 :52 am Marley Young Engineer page 2
Island West Assoc.
Short Plat in Catfish 2nd Section
Stormwater Retention/Detention Pond
BASIN SUMMARY
BASIN ID: AC NAME: 10 YR ROAD R/W 2ND SEC Lt Side
SBUH METHODOLOGY
TOTAL AREA.. . . . . . : 0.16 Acres BASEFLOWS: 0.00 cfs
RAINFALL TYPE. . . . : TYPElA PERV IMP
PRECIPITATION. . . . : 5.40 inches AREA. . : 0. 16 Acres 0. 00 Acres
TIME INTERVAL. . . . : 5.00 min CN. . . . : 81. 00 0.00
ABSTRACTION COEFF: 0. 20 TC. . . . : 29.18 min 0. 00 min
TcReach - Sheet L: 280.00 ns:0.4000 p2yr: 3.90 s:0. 0300
PEAK RATE: 0.09 cfs VOL: 0.04 Ac-ft TIME: 480 min
BASIN ID: ACR NAME: 10 YR ROAD R/W 2ND SEC Rt Side
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0.12 Acres BASEFLOWS: 0.00 cfs
RAINFALL TYPE. . . . : TYPElA PERV IMP
PRECIPITATION. . . . : 5.40 inches AREA. . : 0.12 Acres 0.00 Acres
TIME INTERVAL. . . . : 5.00 min CN. . . . : 81.00 0.00
TC. . . . . 29. 18 min 0. 00 min
ABSTRACTION COEFF: 0. 20
TcReach - Sheet L: 280.00 ns:0.4000 p2yr: 3 . 90 s:0. 0300
PEAK RATE: 0. 07 cfs VOL: 0.03 Ac-ft TIME: 480 min
BASIN ID: AD NAME: 100 YR ROAD R/W 2ND SEC Lt sid
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0.16 Acres BASEFLOWS: 0. 00 cfs
RAINFALL TYPE. . . . : TYPElA PERV IMP
PRECIPITATION. . . . : 7.50 inches AREA. . : 0. 16 Acres 0. 00 Acres
TIME INTERVAL. . . . : 5.00 min CN. . . . : 81 .00 0.00
ABSTRACTION COEFF: 0. 20 TC. . . . : 29.18 min 0.00 min
TcReach - Sheet L: 280.00 ns:0. 4000 p2yr: 3 .90 s:0.0300
PEAK RATE: 0. 15 cfs VOL: 0.07 Ac-ft TIME: 480 min
BASIN ID: ADR NAME: 100 YR ROAD R/W 2ND SEC Rt Sid
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0.12 Acres BASEFLOWS: 0.00 cfs
RAINFALL TYPE. . . . : TYPElA PERV IMP
PRECIPITATION. . . . : 7.50 inches AREA. . : 0.12 Acres 0. 00 Acres
TIME INTERVAL. . . . : 5. 00 min CN. . . . : 81 .00 0.00
ABSTRACTION COEFF: 0. 20 TC. . . . : 29 .18 min 0.00 min
TcReach - Sheet L: 280. 00 ns:0.4000 p2yr: 3 . 90 s:0.0300
PEAK RATE: 0. 11 cfs VOL: 0.05 Ac-ft TIME: 480 min
10/21/96 11:1:53 am Marley Young Engineer page 3
Island West Assoc.
Short Plat in Catfish 2nd Section
Stormwater Retention/Detention Pond
HYDROGRAPH SUMMARY
PEAK TIME VOLUME
HYD RUNOFF OF OF Contrib �=✓a F P,=/-s
NUM RATE PEAK HYDRO Area f1yd
cfs min. cf\AcFt Acres
14.4 1 0.020 485 541 cf 0.16
4,0 2 0.053 485 1195 cf 0.16
,4 C 3 0.090 480 1921 cf 0.16 LT- - /(: i r
*4 p 4 0. 148 480 3032 cf 0. 16 Z-r- - i�o
AAR. 5 0.015 485 398 cf 0. 12 9T - Como
A M K 6 0.039 485 879 cf 0.12 X—r - 2 i-
Ac 2 7 0.066 480 1414 cf 0.12 PT- I6�Ar
AG �� 8 0. 109 480 2231 cf 0. 12 9-r- IMnr //vu-sae
11 0.035 485 939 cf 0. 28 = /+ 5 C�ischa�?a
12 0.092 485 2074 cf 0.28 _ Z+ G
13 0.156 480 3335 cf 0. 28 = 3 + 7
14 0. 256 480 5263 cf 0. 28 = y f 8
10/21/96 11 : 44: 51 am Marley Young Engineer page 1
Island West Assoc.
S P/Catfish 2nd Sec Lt side ditch
Stormwater Retention/Detention Pond
BASIN SUMMARY
BASIN ID: aA NAME: Post 6 MO ROAD R/W 2ND SEC Lt
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0. 16 Acres BASEFLOWS: 0 . 00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 2 . 50 inches AREA. . : 0 . 08 Acres 0 . 08 Acres
TIME INTERVAL. . . . : 5. 00 min CN. . . . : 86 . 90 98 . 00
TC. . . . : 18 . 59 min 18 .59 min
ABSTRACTION COEFF: 0. 20
TcReach - Sheet L: 240 . 00 ns:0. 0600 p2yr: 3 . 90 s:0. 0200
PEAK RATE: 0. 06 cfs VOL: 0 .02 Ac-ft TIME: 480 min
BASIN ID: bA NAME: Post 2 yr ROAD R/W 2ND SEC Lt
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0 . 16 Acres BASEFLOWS: 0.00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 0 . 08 Acres 0 . 08 Acres
TIME INTERVAL. . . . : 5. 00 min CN. . . . : 86. 90 98 . 00
TC. . . . : 18.59 min 18 . 59 min
ABSTRACTION COEFF: 0 . 20
TcReach - Sheet L: 240. 00 ns:0 . 0600 p2yr: 3 . 90 s: 0. 0200
PEAK RATE: 0. 10 cfs VOL: 0 . 04 Ac-ft TIME: 480 min
BASIN ID: cAR NAME: Post 10 yr ROAD R/W 2ND SEC Rt
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0. 12 Acres BASEFLOWS: 0 . 00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 5. 40 inches AREA. . : 0. 06 Acres 0 . 06 Acres
TIME INTERVAL. . . . : 5.00 min CN. . . . : 86. 90 98 . 00
TC. . . . : 18 .59 min 18. 59 min
ABSTRACTION COEFF: 0 . 20
TcReach - Sheet L: 240.00 ns:0 . 0600 p2yr: 3 . 90 s: 0. 0200
PEAK RATE: 0 . 10 cfs VOL: 0 . 04 Ac-ft TIME: 480 min
BASIN ID: dAR NAME: Post 100 yr ROAD R/W 2ND SECRt
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0. 12 Acres BASEFLOWS: 0 .00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 7 . 50 inches AREA. . : 0 . 06 Acres 0.06 Acres
TIME INTERVAL. . . . : 5. 00 min CN. . . . : 86 . 90 98 . 00
TC. . . . : 18 . 59 min 18 . 59 min
ABSTRACTION COEFF: 0 . 20
TcReach - Sheet L: 240.00 ns: 0 .0600 p2yr: 3 . 90 s: 0 . 0200
PEAK RATE: 0. 15 cfs VOL: 0.06 Ac-ft TIME: 480 min
10/21/96 11: 15:44 am Marley Young Engineer page 1
Island West Assoc.
Short Plat in Catfish 2nd Section
Stormwater Retention/Detention Pond
HYDROGRAPH SUMMARY
PEAK TIME VOLUME
HYD RUNOFF OF OF Contrib
NUM RATE PEAK HYDRO Area
cfs min. cf\AcFt Acres -7
----------------------------------
a A 1 0.056 480 1046 cf 0. 16 0T
bA• 2 0.099 480 1809 cf 0.16 LT" "
cA 3 0.145 480 2650 cf 0.16 cT "
d,4 4 0.209 480 3822 cf 0. 16 L7-
N
.a,4�2 5 0.040 480 745 cf 0.12 2�
,bA1,- 6 0.071 480 1300 cf 0. 12 2
CA k 7 0. 105 480 1912 cf 0. 12 (e T
d A(R 8 0.153 480 2783 cf 0. 12 T
��FT D17Cat To a�r�lh
10/21/96 11:44 :52 am Marley Young Engineer page 2
Island West Assoc.
S P/Catfish 2nd Sec Lt side ditch
Stormwater Retention/Detention Pond
HYDROGRAPH SUMMARY
PEAK TIME VOLUME
HYD RUNOFF OF OF Contrib
NUM RATE PEAK HYDRO Area
cfs min. cf\AcFt Acres
---------------------------------------------
---------------------------------------------
1 0.056 480 1046 cf 0. 16 LT
b 4 Z y 2 0.099 480 1809 cf 0.16 z%
c A /0`1 3 0.145 480 2650 cf 0. 16 � r
d A �o� y 4 0.209 480 3822 cf 0.16 G T
o.A F- 5 0.040 480 745 cf 0. 12 T-
A e 6 0.071 480 1300 cf 0. 12 r r
A� 7 0.105 480 1912 cf 0. 12
d A R 8 0.153 480 2783 cf 0. 12 r2T
9 0. 049 495 963 cf 0. 16
10 0.092 490 1726 cf 0.16
11 0. 138 490 2566 cf 0.16
12 0 . 201 490 3738 cf 0. 16
13 0.031 495 164 cf 0.00
14 0.071 490 583 cf 0.00
15 0.117 490 1239 cf 0 .00 Lr
16 0.179 490 2292 cf 0.00 Gr
17 0.019 495 799 cf 0.00 L7- \, �-«---
18 0.020 490 1143 cf 0.00 LT
19 0. 021 490 1328 cf 0.00 -r
20 0.023 490 1445 cf 0.00 =�
fJ//owkl9 �e /TTµ a��schc�f9�
0,031
� . J77
10/21/96 11 :44:52 am Marley Young Engineer page 3
Island West Assoc.
S P/Catfish 2nd Sec Lt side ditch
Stormwater Retention/Detention Pond
STAGE STORAGE TABLE
TRAPEZOIDAL BASIN ID No. 2dlt
Description: 2 Sec Left Ditch Free Flow
Length: 200.00 ft. Width: 1.00 ft.
Side Slope 1 : 3 Side Slope 3: 0
Side Slope 2: 3 Side Slope 4: 0
Infiltration Rate: 45.00 min/inch
STAGE <----STORAGE----> STAGE <----STORAGE----> STAGE <----STORAGE----> STAGE <----STORAGE---->
(ft) ---cf--- --Ac-Ft- (ft) ---cf--- --Ac-Ft- (ft) ---cf--- --Ac-Ft- (ft) ---cf--- --Ac-Ft-
100.00 0.0000 0.0000 100.26 92.560 0.0021 100.52 266.24 0.0061 100.78 521.04 0.0120
100.02 4.2400 0.0001 100.28 103.04 0.0024 100.54 282.96 0.0065 100.80 544.00 0.0125
100.04 8.9600 0.0002 100.30 114.00 0.0026 100.56 300.16 0.0069 100.82 567.44 0.0130
100.06 14.160 0.0003 100.32 125.44 0.0029 100.58 317.84 0.0073 100.84 591.36 0.0136
100.08 19.840 0.0005 100.34 137.36 0.0032 100.60 336.00 0.0077 100.86 615.76 0.0141
100.10 26.000 0.0006 100.36 149.76 0.0034 100.62 354.64 0.0081 100.88 640.64 0.0147
100.12 32.640 0.0007 100.38 162.64 0.0037 100.64 373.76 0.0086 100.90 666.00 0.0153
100.14 39.760 0.0009 100.40 176.00 0.0040 100.66 393.36 0.0090 100.92 691.84 0.0159
100.16 47.360 0.0011 100.42 189.84 0.0044 100.68 413.44 0.0095 100.94 718.16 0.0165
100.18 55.440 0.0013 100.44 204.16 0.0047 100.70 434.00 0.0100 100.96 744.96 0.0171
100.20 64.000 0.0015 100.46 218.96 0.0050 100.72 455.04 0.0104 100.98 772.24 0.0177
100.22 73.040 0.0017 100.48 234.24 0.0054 100.74 476.56 0.0109 101.00 800.00 0.0184
100.24 82.560 0.0019 100.50 250.00 0.0057 100.76 498.56 0.0114
10/21/96 11 :44 :52 am Marley Young Engineer page 4
Island West Assoc.
S P/Catfish 2nd Sec Lt side ditch
Stormwater Retention/Detention Pond
STAGE STORAGE TABLE
Infiltration Rating Curve for Storage Struct 2dlt
STAGE <-INFILTRATION-> STAGE <-INFILTRATION-> STAGE <-INFILTRATION-> STAGE <-INFILTRATION->
(ft) ---cfS-- ------- (ft) ---cfS-- ------- (ft) ---cfS-- ------- (ft) ---cfS-- -------
100.00 0.0062 100.26 0.0164 100.52 0.0266 100.78 0.0368
100.02 0.0070 100.28 0.0171 100.54 0.0273 100.80 0.0376
100.04 0.0077 100.30 0.0179 100.56 0.0281 100.82 0.0384
100.06 0.0085 100.32 0.0187 100.58 0.0289 100.84 0.0391
100.08 0.0093 100.34 0.0195 100.60 0.0297 100.86 0.0399
100.10 0.0101 100.36 0.0203 100.62 0.0305
100.88 0.0407 I
100.12 0.0109 100.38 0.0211 100.64 0.0313 100.90 0.0415
100.14 0.0117 100.40 0.0218 100.66 0.0321 100.92 0.0423
100.16 0.0124 100.42 0.0226 100.68 0.0328 100.94 0.0431
100.18 0.0132 100.44 0.0234 100.70 0.0336 100.96 0.0439
100.20 0.0140 100.46 0.0242 100.72 0.0344 100.98 0.0447
100.22 0.0148 100.48 0.0250 100.74 0.0352 101.00 0.0455
100.24 0.0156 100.50 0.0258 100.76 0.0360
10/21/96 11:44 :52 am Marley Young Engineer page 5
Island West Assoc.
S P/Catfish 2nd Sec Lt side ditch
Stormwater Retention/Detention Pond
STAGE DISCHARGE TABLE
BROAD CRESTED WEIR ID No. w
Description:
cd: 3 . 2100 ' Weir length: 0. 3500 ft.
El: 100.25 ft. Weir Increm: 0.02
STAGE <--DISCHARGE---> STAGE <--DISCHARGE---> STAGE <--DISCHARGE---> STAGE <--DISCHARGE--->
(ft) ---CfS-- ------- (ft) ---CfS-- ------- (ft) ---CfS-- ------- (ft) ---CfS-- -------
------------------
100.25 0.0000 100.44 0.2143 100.64 1.0054 100.84 2.5691
100.26 0.0012 100.46 0.2638 100.66 1.1242 100.86 2.7742
100.28 0.0070 100.48 0.3194 100.68 1.2509 100.88 2.9888
100.30 0.0169 100.50 0.3812 100.70 1.3857 100.90 3.2130
100.32 0.0308 100.52 0.4494 100.72 1.5287 100.92 3.4469
100.34 0.0491 100.54 0.5244 100.74 1.6802 100.94 3.6907
100.36 0.0719 100.56 0.6061 100.76 1.8402 100.96 3.9445
100.38 0.0996 100.58 0.6949 100.78 2.0090 100.98 4.2084
100.40 0.1324 100.60 0.7910 100.80 2.1866 101.00 4.4827
100.42 0.1705 100.62 0.8944 100.82 2.3732
10/21/96 11:44:54 am Marley Young Engineer page 6
Island West Assoc.
S P/Catfish 2nd Sec Lt side ditch
Stormwater Retention/Detention Pond
LEVEL POOL TABLE SUMMARY
MATCH INFLOW -STO- -DIS- <-PEAK-> STORAGE
<--------DESCRIPTION---------> (cfs) (cfs) --id- --id- <-STAGE> id VOL (cf)
6 month storm event .......... 0.06 0.06 2d1t w 100.32 9 125.23 cf
2 year storm event ........... 0.10 0.10 2d1t w 100.36 10 149.41 cf
10 year storm event .......... 0.15 0.15 2d1t w 100.39 11 169.56 cf
100 year storm event ......... 0.21 0.21 2d1t w 100.42 12 192.45 cf
10/21/96 12:2 :18 am Marley Young Engineer page 1
Island West Assoc.
S P/Catfish 2nd Sec Rt side Pond
Stormwater Retention/Detention Pond
BASIN SUMMARY
BASIN ID: aAR NAME: Post 6 MO ROAD R/W 2ND SEC Rt
SBUH METHODOLOGY
TOTAL AREA: . . . . . . : 0.12 Acres BASEFLOWS: 0.00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 2.50 inches AREA. . : 0.06 Acres 0.06 Acres
TIME INTERVAL. . . . : 5.00 min CN. . . . : 86.90 98.0
0
TC. . . . : 18.59 min 18.59 min
ABSTRACTION COEFF: 0.20
TcReach - Sheet L: 240. 00 ns:0. 0600 p2yr: 3.90 s:0. 0200
PEAK RATE: 0.04 cfs VOL: 0.02 Ac-ft TIME: 480 min
BASIN ID: bAR NAME: Post 2 yr ROAD R/W 2ND SEC Rt
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0.12 Acres BASEFLOWS: 0.00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 3 .90 inches AREA. . : 0. 06 Acres 0. 06 Acres
TIME INTERVAL. . . . : 5.00 min CN. . . . : 86.90 98. 00
TC. . . . : 18.59 min 18.59 min
ABSTRACTION COEFF: 0. 20
TcReach - Sheet L: 240.00 ns:0.0600 p2yr: 3 .90 s:0.0200
PEAK RATE: 0.07 cfs VOL: 0.03 Ac-ft TIME: 480 min
BASIN ID: cAR NAME: Post 10 yr ROAD R/W 2ND SEC Rt
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0.12 Acres BASEFLOWS: 0.00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 5. 40 inches AREA. . : 0. 06 Acres 0. 06 Acres
TIME INTERVAL. . . . : 5.00 min CN. . . . : 86. 90 98.00
TC. . . . : 18.59 min 18.59 min
ABSTRACTION COEFF: 0.20
TcReach - Sheet L: 240.00 ns:0.0600 p2yr: 3 . 90 s:0.0200
PEAK RATE: 0.10 cfs VOL: 0.04 Ac-ft TIME: 480 min
BASIN ID: dAR NAME: Post 100 yr ROAD R/W 2ND SECRt
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0.12 Acres BASEFLOWS: 0.00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 7.50 inches AREA. . : 0.06 Acres 0. 06 Acres
TIME INTERVAL. . . . : 5.00 min CN. . . . : 86.90 98.00
ABSTRACTION COEFF: 0.20 TC. . . . : 18.59 min 18.59 min
TcReach - Sheet L: 240.00 ns:0.0600 p2yr: 3 .90 s:0.0200
PEAK RATE: 0.15 cfs VOL: 0.06 Ac-ft TIME: 480 min
10/21/96 12 :2:19 am Marley Young Engineer page 2
Island West Assoc.
S P/Catfish 2nd Sec Rt side Pond
Stormwater Retention/Detention Pond
HYDROGRAPH SUMMARY
PEAK TIME VOLUME
HYD RUNOFF OF OF Contrib
NUM RATE PEAK HYDRO Area
cfs min. cf\AcFt Acres
1 0.056 480 1046 cf 0.16
2 0.099 480 1809 cf 0. 16
3 0.145 480 2650 cf 0. 16
4 0.209 480 3822 cf 0.16
QAP- 5 0. 040 480 745 cf 0. 12 Z-r
6A,R 6 0.071 480 1300 cf 0.12 eT
c t*P, 7 0.105 480 1912 cf 0.12 2--
dAK 8 0.153 480 2783 cf 0. 12 9T
9 0.010 790 650 cf 0.12
10 0.015 800 997 cf 0.12
11 0. 024 785 1366 cf 0.12
12 0.092 515 2141 cf 0. 12
15 0.004 785 46 cf 0.00
16 0.072 515 710 cf 0.00
17 0. 010 790 650 cf 0. 00
18 0.015 800 997 cf 0.00
19 0.020 785 1320 cf 0.00
20 0.021 515 1431 cf 0.00
l O Q O '-f Q �C
10/21/96 12:2: 19 am Marley Young Engineer page 3
-Island West Assoc.
S P/Catfish 2nd Sec Rt side Pond
Stormwater Retention/Detention Pond
STAGE STORAGE TABLE
TRAPEZOIDAL BASIN ID No. t
Description: Pond at
Length: '20.00 ft. Width: 7.00 ft.
Side Slope 1: 3 Side Slope 3 : 3
Side Slope 2: 3 Side Slope 4: 3
Infiltration Rate: 45.00 min/inch
STAGE <----STORAGE----> STAGE <----STORAGE----> STAGE <----STORAGE----> STAGE <----STORAGE---->
(ft) ---cf--- --Ac-Ft- (ft) ---cf--- --Ac-Ft- (ft) ---cf--- --Ac-Ft- (ft) ---cf--- --Ac-Ft-
100.00 0.0000 0.0000 100.65 128.52 0.0030 101.30 345.25 0.0079 101.95 669.98 0.0154
100.05 7.2040 0.0002 100.70 141.81 0.0033 101.35 366.15 0.0084 102.00 700.00 0.0161
100.10 14.822 0.0003 100.75 155.63 0,0036 101.40 387.69 0.0089 102.05 730.78 0.0168
100.15 22.863 0.0005 100.80 169.98 0.0039 101.45 409.89 0.0094 102.10 762.34 0.0175
100.20 31.336 0.0007 100.85 184.89 0.0042 101.50 432.75 0.0099 102.15 794.68 0.0182
100.25 40.250 0.0009 100.90 200.36 0.0046 101.55 456.29 0.0105 102.20 827.82 0.0190
100.30 49.614 0.0011 100.95 216,39 0.0050 101.60 480.51 0.0110 102.25 861.75 0,0198
100.35 59.437 0.0014 101.00 233.00 0.0053 101.65 505.43 0.0116 102.30 896.49 0.0206
100.40 69.728 0.0016 101.05 250.19 0.0057 101.70 531.05 0.0122 102.35 932.06 0.0214
100.45 80.496 0.0018 101.10 267.98 0.0062 101.75 557.38 0.0128 102.40 968.45 0.0222
100.50 91.750 0.0021 101.15 286.37 0.0066 101.80 584.42 0.0134 102.45 1006 0.0231
100.55 103.50 0.0024 101.20 305.38 0.0070 101.85 612.20 0.0141 102.50 1044 0.0240
100.60 115.75 0.0027 101.25 325.00 0.0075 101.90 640.72 0.0147
10/21/96 12:2:19 am Marley Young Engineer page 4
Island West Assoc.
S P/Catfish 2nd Sec Rt side Pond
Stormwater Retention/Detention Pond
STAGE STORAGE TABLE
Infiltration Rating Curve for Storage Struct t
STAGE <-INFILTRATION-> STAGE <-INFILTRATION-> STAGE <-INFILTRATION-> STAGE <-INFILTRATION->
(ft) ---cfS-- ------- (ft) ---cfS-- ------- (ft) cfS-- (ft) cfS--
--- ------- --- -------
----------------
100.00 0.0043 100.65 0.0082 101.30 0.0132 101.95 0.0191
100.05 0.0046 100.70 0.0086 101.35 0.0136 102.00 0.0195
100.10 0.0049 100.75 0.0089 101.40 0.0140 102.05 0.0200
100.15 0.0051 100.80 0.0093 101.45 0.0144 102.10 0.0206
100.20 0.0054 100.85 0.0096 101.50 0.0149 102.15 0.0211
100.25 0.0057 100.90 0.0100 101.55 0.0153 102.20 0.0216
100.30 0.0060 100.95 0.0104 101.60 0.0158 102.25 0.0221
100.35 0.0063 101.00 0.0108 101.65 0.0162 102.30 0.0226
100.40 0.0066 101.05 0.0111 101.70 0.0167 102.35 0.0232
100.45 0.0069 101.10 0.0115 101.75 0.0171 102.40 0.0237
100.50 0.0072 101.15 0.0119 101.80 0.0176 102.45 0.0243
100.55 0.0076 101.20 0.0123 101.85 0.0181 102.50 0.0248
100.60 0.0079 101.25 0.0127 101.90 0.0186
10/21/96 12 :2: 19 am Marley Young Engineer page 5
Island West Assoc.
S P/Catfish 2nd Sec Rt side Pond
Stormwater Retention/Detention Pond
STAGE DISCHARGE TABLE
BROAD CRESTED WEIR ID No. w
Description:
cd: 3 . 2100 * Weir length: 0.5000 ft.
El: 102.00 ft. Weir Increm: 0.02
STAGE <--DISCHARGE---> STAGE <--DISCHARGE---> STAGE <--DISCHARGE---> STAGE <--DISCHARGE--->
(ft) ---CfS-- ------- (ft) ---cfS-- ------- (ft) ---cfS-- ------- (ft) ---cfS-- -------
102.00 0.0000 102.14 0.1406 102.28 0.5574 102.42 1.3176
102.02 0.0050 102.16 0.1816 102.30 0.6435 102.44 1.4578
102.04 0.0153 102.18 0.2285 102.32 0.7368 102.46 1.6064
102.06 0.0304 102.20 0.2814 102.34 0.8375 102.48 1.7635
102.08 0.0503 102.22 0.3405 102.36 0.9457 102.50 1.9293
102.10 0.0751 102.24 0.4061 102.38 1.0617
102.12 0.1051 102.26 0.4783 102.40 1.1856
10/21/96 12: 2: 25 am Marley Young Engineer page 6
Island West Assoc.
S P/Catfish 2nd Sec Rt side Pond
Stormwater Retention/Detention Pond
---------------------------------------------------------------------
---------------------------------------------------------------------
LEVEL POOL TABLE SUMMARY
MATCH INFLOW -STO- -DIS- <-PEAK-> STORAGE
<--------DESCRIPTION---------> (cfs) (cfs) --id- --id- <-STAGE> id VOL (cf)
6 month storm event .......... 0.04 0.04 t w 100.89 9 196.63 cf
2 year storm event ........... 0.07 0.07 t * w 101.52 10 443.39 cf
10 year storm event .......... 0.10 0.10 t w 102.02 11 710.90 cf
100 year storm event ......... 0.15 0.15 t w 102.10 12 760.64 cf
10/21/96 10: 35:55 am Marley Young Engineer page 1
Island West Assoc.
Short Plat in Catfish 1st Section
Stormwater Retention/Detention Pond
BASIN SUMMARY
BASIN ID: A NAME: 6 MO ROAD R/W 1st section
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0.05 Acres BASEFLOWS: 0. 00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 2.50 inches AREA. . : 0.05 Acres 0.00 Acres
TIME INTERVAL. . . . : 2.00 min CN. . . . : 81 .00 0.00
TC. . . . . 11 .17 min 0.00 min
ABSTRACTION COEFF: 0.20
TcReach - Sheet L: 100.00 ns:0.4000 p2yr: 3 .90 s:0.0800
PEAK RATE: 0 . 01 cfs VOL: 0.00 Ac-ft TIME: 480 min
BASIN ID: B NAME: 2 YR ROAD R/W 1st section
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0. 05 Acres BASEFLOWS: 0. 00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 3 . 95 inches AREA. . : 0. 05 Acres 0.00 Acres
TIME INTERVAL. . . . : 2.00 min CN. . . . : 81 . 00 0.00
ABSTRACTION COEFF: 0. 20 TC. . . . : 11 . 17 min 0.00 min
TcReach - Sheet L: 100.00 ns:0.4000 p2yr: 3 . 90 s:0.0800
PEAK RATE: 0.02 cfs VOL: 0.00 Ac-ft TIME: 480 min
BASIN ID: C NAME: 10 YR ROAD R/W 1st section
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0.05 Acres BASEFLOWS: 0.00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 5.40 inches AREA. . : 0 . 05 Acres 0.00 Acres
TIME INTERVAL. . . . :
2. 00 min CN. . . . : E1.00 0. 00
ABSTRACTION COEFF: 0.20 TC. . . . : 11.17 min 0.00 min
TcReach - Sheet L: 100.00 ns: 0.4000 p2yr: 3 .90 s: 0.0800
PEAK RATE: 0.03 cfs VOL: 0.01 Ac-ft TIME: 480 min
BASIN ID: D NAME: 100 YR ROAD R/W 1st Section
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0. 05 Acres BASEFLOWS: 0 . 00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 7.50 inches AREA. . : 0.05 Acres 0. 00 Acres
II, TIME INTERVAL. . . . : 2. 00 min CN. . . . : 81.00 0.00
ABSTRACTION COEFF: 0.20 TC. . . . : 11.17 min 0. 00 min
TcReach - Sheet L: 100. 00 ns: 0. 4000 p2yr: 3 .90 s:0.0800
PEAK RATE: 0.05 cfs VOL: 0.01 Ac-ft TIME: 480 min
10/21/96 10: 35:55 am Marley Young Engineer page 2
Island West Assoc.
Short Plat in Catfish 1st Section
Stormwater Retention Detention Pond
BASIN SUMMARY
BASIN ID: a NAME: 6 MO ROAD R/W 1st section
SBUH METHODOLOGY
TOTAL AREA: . . . . . . : 0.05 Acres BASEFLOWS: 0.00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 2 .50 inches AREA. . : 0.02 Acres 0.02 Acres
TIME INTERVAL. . . . : 2.00 min CN. . . . : 86.90 98.00
TC. . . . : 10.00 min 10. 00 min
ABSTRACTION COEFF: 0.20
TcReach - Sheet L: 80.00 ns:0. 4000 p2yr: 3 . 90 s:0.0900
PEAK RATE: 0.02 cfs VOL: 0.00 Ac-ft TIME: 480 min
BASIN ID: b NAME: 2 yr ROAD R/W 1st sectio
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0. 05 Acres BASEFLOWS: 0.00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 3 .90 inches AREA. . : 0.02 Acres 0 .02 Acres
TIME INTERVAL. . . . : 2.00 min CN. . . . : 86.90 98.00
TC. . . . : 10.00 min 10.00 min
ABSTRACTION COEFF: 0. 20
TcReach - Sheet L: 80.00 ns:0.4000 p2yr: 3 .90 s:0.0900
PEAK RATE: 0. 03 cfs VOL: 0 . 01 Ac-ft TIME: 480 min
BASIN ID: c NAME: 10 yr ROAD R/W 1st sectio
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0.05 Acres BASEFLOWS: 0. 00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 5.40 inches AREA. . : 0.02 Acres 0 .02 Acres
TIME INTERVAL. . . . : 2 . 00 min CN. . . . : 86. 90 98.00
TC. . . . : 10.00 min 10 . 00 min
ABSTRACTION COEFF: 0. 20
TcReach - Sheet L: 80.00 ns:0. 4000 p2yr: 3 .90 s:0. 0900
PEAK RATE: 0.05 cfs VOL: 0.01 Ac-ft TIME: 480 min
BASIN ID: d NAME: 100 yr road r/w 1st section
SBUH METHODOLOGY
TOTAL AREA. . . . . . . : 0. 05 Acres BASEFLOWS: 0.00 cfs
RAINFALL TYPE. . . . : TYPEIA PERV IMP
PRECIPITATION. . . . : 7.50 inches AREA. . : 0 . 02 Acres 0.02 Acres
TIME INTERVAL. . . . : 2.00 min CN. . . . : 86.90 98.00
TC. . . . : 10.00 min 10. 00 min
ABSTRACTION COEFF: 0.20
TcReach - Sheet L: 280.00 ns:0.4000 p2yr: 3 .90 s:0.0300
PEAK RATE: 0.07 cfs VOL: 0.01 Ac-ft TIME: 480 min
10/21/96 10: 35:56 am Marley Young Engineer page 3
Island West Assoc.
Short Plat in Catfish 1st Section
Stormwater Retention/Detention Pond
HYDROGRAPH SUMMARY
PEAK TIME VOLUME
HYD RUNOFF OF OF Contrib
NUM RATE PEAK HYDRO Area
cfs min. cf\AcFt Acres
1 0.008 480 46 cf 0. 05
2 0.020 480 128 cf 0. 05
3 0.034 480 229 cf 0. 05
4 0.054 480 393 cf 0.05
5 0.018 480 141 cf 0.05
6 0.031 480 257 cf 0. 05
7 0. 046 480 389 cf 0 .05
8 0.067 480 579 cf 0.05
10 0.025 488 95 cf 0.05
11 0.046 482 226 cf 0.05
12 0 .066 482 414 cf 0.05
14 0.012 488 16 cf 0.00
15 0.033 482 101 cf 0. 00
16 0.053 482 226 cf 0. 00
18 0.013 488 79 cf 0. 00
19 0. 013 482 124 cf 0.00
20 0. 013 482 187 cf 0.00
10/21/96 10: 35:56 am Marley Young Engineer page 4
Island West Assoc.
Short Plat in Catfish 1st Section
Stormwater Retention/Detention Pond
STAGE STORAGE TABLE
TRAPEZOIDAL BASIN ID No. at
Description: Infiltration trench or 8%slope
Length: . 7.00 ft. Width: 5.60 ft. X 3VO'z7QAT10 = 14 -60
Side Slope 1: 1 Side Slope 3 : 0
Side Slope 2 : 1 Side Slope 4: 0
Infiltration Rate: 15.00 min/inch ,c 3 vooz;, tza<<�
STAGE <----STORAGE----> STAGE <----STORAGE----> STAGE <----STORAGE----> STAGE <----STORAGE---->
(ft) ---cf--- --Ac-Ft- (ft) ---cf--- --Ac-Ft- (ft) ---cf--- --Ac-Ft- (ft) ---cf--- --Ac-Ft-
--------------------------------------------------------------------------------------------------------
100.00 0.0000 0.0000 100.76 33.835 0.0008 101.52 75.757 0.0017 102.28 125.76 0.0029
100.02 0.7868 0.0000 100.78 34.835 0.0008 101.54 76.969 0.0018 102.30 127.19 0.0029
100.04 1.5792 0.0000 100.80 35.840 0.0008 101.56 78.187 0.0018 102.32 128.62 0.0030
100.06 2.3772 0.0001 100.82 36.851 0.0008 101.58 79.411 0.0018 102.34 130.06 0.0030
100.08 3.1808 0.0001 100.84 37.867 0.0009 101.60 80.640 0.0019 102.36 131.50 0.0030
100.10 3.9900 0.0001 100.86 38.889 0.0009 101.62 81.875 0.0019 102.38 132.95 0.0031
100.12 4.8048 0.0001 100.88 39.917 0.0009 101.64 83.115 0.0019 102.40 134.40 0.0031
100.14 5.6252 0.0001 100.90 40.950 0.0009 101.66 84.361 0.0019 102.42 135.86 0.0031
100.16 6.4512 0.0001 100.92 41.989 0.0010 101.68 85.613 0.0020 102.44 137.32 0.0032
100.18 7.2828 0.0002 100.94 43.033 0.0010 101.70 86.870 0.0020 102.46 138.79 0.0032
100.20 8.1200 0.0002 100.96 44.083 0.0010 101.72 88.133 0.0020 102.48 140.27 0.0032
100.22 8.9628 0.0002 100.98 45.139 0.0010 101.74 89.401 0.0021 102.50 141.75 0.0033
100.24 9.8112 0.0002 101.00 46.200 0.0011 101.76 90.675 0.0021 102.52 143.24 0.0033
100.26 10.665 0.0002 101.02 47.267 0.0011 101.78 91.955 0.0021 102.54 144.73 0.0033
100.28 11.525 0.0003 101.04 48.339 0.0011 101.80 93.240 0,0021 102.56 146.23 0.0034
100.30 12.390 0.0003 101.06 49.417 0.0011 101.82 94.531 0.0022 102.58 147.73 0.0034
100.32 13.261 0.0003 101.08 50.501 0.0012 101.84 95.827 0.0022 102.60 149.24 0.0034
100.34 14.137 0.0003 101.10 51.590 0.0012 101.86 97.129 0.0022 102.62 150.75 0.0035
100.36 15.019 0.0003 101.12 52.685 0.0012 101.88 98.437 0.0023 102.64 152.28 0.0035
100.38 15.907 0.0004 101.14 53.785 0.0012 101.90 99.750 0.0023 102.66 153.80 0.0035
100.40 16.800 0.0004 101.16 54.891 0.0013 101.92 101.07 0.0023 102.68 155.33 0.0036
100.42 17.699 0.0004 101.18 56.003 0.0013 101.94 102.39 0.0024 102.70 156.87 0.0036
100.44 18.603 0.0004 101.20 57.120 0.0013 101.96 103.72 0.0024 102.72 158.41 0.0036
100.46 19.513 0.0004 101.22 58.243 0.0013 101.98 105.06 0.0024 102.74 159.96 0.0037
100.48 20.429 0.0005 101.24 59.371 0.0014 102.00 106.40 0.0024 102.76 161.52 0.0037
100.50 21.350 0.0005 101.26 60.505 0.0014 102.02 107.75 0.0025 102.78 163.07 0.0037
100.52 22.277 0.0005 101.28 61.645 0.0014 102.04 109.10 0.0025 102.80 164.64 0.0038
100.54 23.209 0.0005 101.30 62.790 0.0014 102.06 110.46 0.0025 102.82 166.21 0.0038
100.56 24.147 0.0006 101.32 63.941 0.0015 102.08 111.82 0.0026 102.84 167.79 0.0039
100.58 25.091 0.0006 101.34 65.097 0.0015 102.10 113.19 0.0026 102.86 169.37 0.0039
100.60 26.040 0.0006 101.36 66.259 0.0015 102.12 114.56 0.0026 102.88 170.96 0.0039
100.62 26.995 0.0006 101.38 67.427 0.0015 102.14 115.95 0.0027 102.90 172.55 0.0040
100.64 27.955 0.0006 101.40 68.600 0.0016 102.16 117.33 0.0027 102.92 174.15 0.0040
100.66 28.921 0.0007 101.42 69.779 0.0016 102.18 118.72 0.0027 102.94 175.75 0.0040
100.68 29.893 0.0007 101.44 70.963 0.0016 102.20 120.12 0.0028 102.96 177.36 0.0041
100.70 30.870 0.0007 101.46 72.153 0.0017 102.22 121.52 0.0028 102.98 178.98 0.0041
100.72 31.853 0.0007 101.48 73.349 0.0017 102.24 122.93 0.0028 103.00 180.60 0.0041
100.74 32.841 0.0008 101.50 74.550 0.0017 102.26 124.35 0.0029
10/21/96 10:35:56 am Marley Young Engineer page 5
Island West Assoc.
Short Plat in Catfish 1st Section
Stormwater Retention/Detention Pond
---------------------------------------------------------------------
---------------------------------------------------------------------
STAGE STORAGE TABLE
Infiltration Rating Curve for Storage Struct at
STAGE <-INFILTRATION-> STAGE <-INFILTRATION-> STAGE <-INFILTRATION-> STAGE <-INFILTRATION->
(ft) ---cfs-- ------- (ft) ---cfs-- ------- (ft) ---cfs-- ------- (ft) ---cfs-- -------
--------------------------------------------------------------------------------------------------------
--------------------------------------------------------------------------------------------------------
100.00 0.0036 100.76 0.0059 101.52 0.0084 102.28 0.0111
100.02 0.0037 100.78 0.0060 101.54 0.0085 102.30 0.0112
100.04 0.0037 100.80 0.0060 101.56 0.0086 102.32 0.0113
100.06 0.0038 100.82 0.0061 101.58 0.0086 102.34 0.0114
100.08 0.0039 100.84 0.0062 101.60 0.0087 102.36 0.0114
100.10 0.0039 100.86 0.0062 101.62 0.0088 102.38 0.0115
100.12 0.0040 100.88 0.0063 101.64 0.0088 102.40 0.0116
100.14 0.0040 100.90 0.0064 101.66 0.0089 102.42 0.0117
100.16 0.0041 100.92 0.0064 101.68 0.0090 102.44 0.0117
100.18 0.0042 0 1 0.94 0.0065 101.70 0.0090 102.46 0.0118
100.20 0.0042 100.96 0.0066 101.72 0.0091 102.48 0.0119
100.22 0.0043 100.98 0.0066 .7 101 4 0.0092 102.50 0.0120
100.24 0.0043 101.00 0.0067 101.76 0.0093 102.52 0.0120
100.26 0.0044 101.02 0.0067 101.78 0.0093 102.54 0.0121
100.28 0.0044 101.04 0.0068 101.80 0.0094 102.56 0.0122
100.30 0.0045 101.06 0.0069 101.82 0.0095 102.58 0.0123
100.32 0.0046 101.08 0.0069 101.84 0.0095 102.60 0.0123
100.34 0.0046 101.10 0.0070 101.86 0.0096 102.62 0.0124
100.36 0.0047 101.12 0.0071 101.88 0.0097 102.64 0.0125
100.38 0.0047 101.14 0.0071 101.90 0.0098 102.66 0.0126
100.40 0.0048 101.16 0.0072 101.92 0.0098 102.68 0.0127
100.42 0.0049 101.18 0.0073 101.94 0.0099 102.70 0.0127
100.44 0.0049 101.20 0.0073 101.96 0.0100 102.72 0.0128
100.46 0.0050 101.22 0.0074 101.98 0.0100 102.74 0.0129
100.48 0.0051 101.24 0.0075 102.00 0.0101 102.76 0.0130
100.50 0.0051 101.26 0.0075 102.02 0.0102 102.78 0.0130
100.52 0.0052 101.28 0.0076 102.04 0.0103 102.80 0.0131
100.54 0.0052 101.30 0.0077 102.06 0.0103 102.82 0.0132
100.56 0.0053 101.32 0.0077 102.08 0.0104 102.84 0.0133
100.58 0.0054 101.34 0.0078 102.10 0.0105 102.86 0.0134
100.60 0.0054 101.36 0.0079 102.12 0.0105 102.88 0.0134
100.62 0.0055 101.38 0.0079 102.14 0.0106 102.90 0.0135
100.64 0.0055 101.40 0.0080 102.16 0.0107 102.92 0.0136
100.66 0.0056 101.42 0.0081 102.18 0.0108 102.94 0.0137
100.68 0.0057 101.44 0.0081 102.20 0.0108 102.96 0.0137
100.70 0.0057 101.46 0.0082 102.22 0.0109 102.98 0.0138
100.72 0.0058 101.48 0.0083 102.24 0.0110 103.00 0.0139
100.74 0.0059 101.50 0.0084 102.26 0.0111
10/21/96 10: 35:57 am Marley Young Engineer page 6
Island West Assoc.
Short Plat in Catfish 1st Section
Stormwater Retention/Detention Pond
STAGE DISCHARGE TABLE
BROAD CRESTED WEIR ID No. w
Description:
cd: 3.2100 * Weir length: 0. 3500 ft.
El: 102.75 ft. Weir Increm: 0.02
STAGE <--DISCHARGE---> STAGE <--DISCHARGE---> STAGE <--DISCHARGE---> STAGE <--DISCHARGE--->
(ft) ---CfS-- ------- (ft) ---cfS-- ------- (ft) ---cfS-- ------- (ft) ---cfS-- -------
102.75 0.0000 102.82 0.0308 102.90 0.1324 102.98 0.3194
102.76 0.0012 102.84 0.0491 102.92 0.1705 103.00 0.3812
102.78 0.0070 102.86 0.0719 102.94 0.2143
102.80 0.0169 102.88 0.0996 102.96 0.2638
10/21/96 10: 36: 2 am Marley Young Engineer page 7
Island West Assoc.
Short Plat in Catfish 1st Section
Stormwater Retention/Detention Pond
---------------------------------------------------------------------
---------------------------------------------------------------------
LEVEL POOL TABLE SUMMARY
MATCH INFLOW -STO- -DIS- <-PEAK-> STORAGE
<------—DESCRIPTION---------> (cfs) (cfs) --id- --id- <-STAGE> id VOL (cf)
----------------------------------------------------------------------------
-----------------------------------------------------------------------------
6 month storm event .......... 0.00 0.02 at w 102.48 9 140.11 cf
2 year storm event ........... 0.02 0.03 at w 102.79 10 163.84 cf
10 year storm event .......... 0.03 0.05 at w 102.82 11 166.36 cf
100 year storm event ......... 0.05 0.07 at w 102.84 12 168.06 cf