20090040 Ver 1_More Info Received_20090312

Department of Environment and Natural Resources
Division of Water Quality
Attn: Ian McMillan/Annette Lucas
2321 Crabtree Boulevard, Suite 250
Raleigh, NC 27604

March 12, 2009
S&EC Project # 10708.P1
DWQ Project #09-0040
Re: Reply to the Division of Water Quality's 2/12/09 Request for More Information
Beacon Lake Industrial Commons
Raleigh, Wake County, NC
Dear Mr. McMillan and Ms. Lucas:
This letter is in response to your letter dated February 12, 2009 which requested additional
information for the proposed Beacon Lake Industrial Commons development. The following
restates your questions/comments and is then followed by our response.
1. The stormwater management plan for the road must be submitted in final
form. Please provide appropriate BMP Supplement Forms for each of the
proposed Bioretention Cells with ALL required items, including plans, details,
calculations and operation and maintenance agreements.
Please see the attached documentation per your request and recent telephone conversations.
2. Please provide a conceptual stormwater management plan for the project that
includes the following:
a. A depiction of the drainage areas on the site.
b. An estimation of the percentage imperviousness associated with
each of the drainage areas.
c. A calculation of the water quality volume associated with each
drainage area.
d. A depiction of a proposed BMP (state the type of BMP you plan to
use) on the site plan that is correctly sized based on the water quality
volume.
Please see the attached revised plans that clearly show and detail the proposed BMPs for each lot
of the proposed industrial park.
Charlotte Office: Greensboro Office:
236 LePhillip Court, Suite C 3817-E Lawndale Drive
Concord, NC 28025 Greensboro, NC 27455
Phone: [phone] Phone: [phone]
Fax: [phone] Fax:
[phone]
Please feel free to call me if you require any further explanation.
Sincerely,
i'
Nicole J. omson
Regulatory Specialist
Attachments: 5 copies of DWQ Request for more information letter (2/12/09)
5 copies of Response letter
5 copies of Stormwater Calculations
5 copies of revised construction drawings
5 copies of revised post construction drainage map
TI-Yri
NCDENR
North Carolina Department of Environment and Natural Resources
Division of Water Quality
Beverly Eaves Perdue Coleen H. Sullins Dee Freeman
Governor Director Secretary
February 12, 2009
CERTIFIED MAIL: RETURN RECEIPT REQUESTED
Mr. Patrick Denton
Beacon Lake Industrial Commons, LLC
5112 Departure Drive
Raleigh, NC 27616
Subject Property: Beacon Lake Industrial Commons
Ut to Crabtree Creek [030402, 27-33-(10), C, NSW]
REQUEST FOR MORE INFORMATION
Dear Mr. Denton:
DWQ Project # 09-0040
Wake County
a F'
E 17 2009
By: SE0 61:tt r antal Cunsultants, PA
On January 9, 2009, the Division of Water Quality (DWQ) received your application dated January 9,
2009, to fill or otherwise impact 0.0015 acres of 404/wetland, 188 linear feet of perennial stream (148
linear feet of permanent impact and 40 linear feet of temporary impact), and 8,545 square feet of Zone I
Neuse River basin protected riparian buffer, and 4,631 square feet of Zone 2 Neuse River basin protected
riparian buffer, to construct the proposed light industrial park at the site. The DWQ has determined that
your application was incomplete and/or provided inaccurate information as discussed below. The DWQ
will require additional information in order to process your application to impact protected wetlands
and/or streams on the subject property. Therefore, unless we receive five copies of the additional
information requested below, we will place this project on hold as incomplete until we receive this
additional information. If we do not receive the requested information, your project will be formally
returned as incomplete. Please provide the following information so that we may continue to review your
project.
Additional Information Requested:
1. The stormwater management plan for the road must be submitted in final form. Please provide
appropriate BMP Supplement Forms for each of the proposed Bioretention Cells with ALL
required items, including plans, details, calculations and operation and maintenance agreements.
2. Please provide a conceptual stormwater management plan for the remainder of the project that
includes the following:
a. A depiction of the drainage areas on the site.
b. An estimation of the percentage imperviousness associated with each of the drainage
areas.
c. A calculation of the water quality volume associated with each drainage area.
401 Oversight/Express Review Permitting Unit
1650 Mail Service Center, Raleigh, North Carolina 27699-1650
Location: 2321 Crabtree Blvd., Raleigh, North Carolina 27604
Phone: [phone] FAX: [phone]
Internet: http://h2o.enr.state.nc.us/ncwetiands/
NorthCarolina
0/aturamy
An Equal Opportunity t Affirmative Action Employer
Beacon Lake Industrial Commons, LLC
Page 2 of 2
February 12, 2009
d. A depiction of a proposed BMP (state the type of BMP you plan to use) on the site plan
that is correctly sized based on the water quality volume.
Please submit this information within 30 calendar days of the date of this letter. If we do not receive this
requested information within 30 calendar days of the date of this letter, your project will be withdrawn and
you will need to reapply with a new application and a new fee.
This letter only addresses the application review and does not authorize any impacts to wetlands, waters or
protected buffers. Please be aware that any impacts requested within your application are not authorized (at
this time) by the DWQ. Please call Ms. Cyndi Karoly or Mr. Ian McMillan at 919-733-1786 if you have
any questions regarding or would like to set up a meeting to discuss this matter.
Sin Yely,
yndi Karoly, Supervisor
401 Oversight/Express Review Permitting Unit
CBK/Um
cc: USACE Raleigh Regulatory Field Office
Lauren Witherspoon, DWQ Raleigh Regional Office
DLR Raleigh Regional Office
File Copy
Matt Matthews, DWQ Wetlands and Stormwater Branch Manager
Nicole J. Thomson, S&EC, P.A., 11010 Raven Ridge Road, Raleigh, NC 27614
Filename: 090040BeaconLa keInd ustrialCommons(W a ke)On_Hold
BEACON LAKE
INDUSTRIAL COMMONS
Bio-Retention Cell Design Summary
for Compliance with NCDWQ and
City of Raleigh Stormwater Requirements
Prepared By:
Bass, Nixon & Kennedy, Inc.
Consulting Engineers
;NU JtHL
Z 23072
60
'9
??rr`urnumiiu?u?????'
BASS, NIXON & KENNEDY, INC., CONSULTING
3319 Heritage Trade Dr., Ste. 201 WAKE FOREST, NC 27587
P: 919/851-4422 [e-mail]
F: 919/570-1362 [e-mail]
NCDWQ Bio-Retention Cell
Supplemental Checklist
Permit Number:
(to be provided by DWQ)A",
? y v
r
NCDENR °
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
401 CERTIFICATION APPLICATION FORM
BIORETENTION CELL SUPPLEMENT
This form must be filled out, printed and submitted.
The Required Items Checklist (Part l11) must be printed, filled out and submitted along with all of the required information,
L. PROJECT INFORMATION'` ;. - -
Project name Beacon Lake Industrial Commons
Contact name Harry Mitchell, PE or Keith Tew, PE
Phone number 919-8514422
Date March 9, 2009
Drainage area number 1
)I, DESIGNINFORMATION -T-'
Site Characteristics
Drainage area 85,553 ft2
Impervious area 65,610 ft2
Percent impervious 76.7% %
Design rainfall depth 1.0 inch
Peak Flow Calculations
Is pre/post control of the 1-yr, 24-hr peak flow required?
1-yr, 24-hr runoff depth
1-yr, 24-hr intensity
Pre-development 1-yr, 24-hr peak flow
Post-development 1-yr, 24-hr peak flow
Pre/Post 1-yr, 24-hr peak control
Storage Volume: Non-SA Waters
Minimum volume required
Volume provided
Storage Volume: SA Waters
1.5" runoff volume
Pre-development 1-yr, 24-hr runoff
Post-development 1-yr, 24-hr runoff
Minimum volume required
Volume provided
Cell Dimensions
Ponding depth of water
Ponding depth of water
Surface area of the top of the bioretention cell
Length:
Width:
-or- Radius
Media and Soils Summary
Drawdown time, ponded volume
Drawdown time, to 24 inches below surface
Drawdown time, total:
In-situ soil:
Soil permeability
Planting media soil:
Soil permeability
Soil composition
% Sand (by weight)
% Fines (by weight)
% Organic (by weight)
Phosphorus Index (P-Index) of media
N (Y or N)
ft 3 /sec
ft 3 /sec
5,289.0 ft3
5,411.0 ft3 OK
N/A ft 3
ft 3
ft3
N/A ft3
rJ?a ft3
12 inches OK
1.00 ft
5,842.0 ft2 OK
69 ft OK
85 ft OK
N/A ft OK
12 hr
24 hr
36 hr
1.00 in/hr
1.00 in/hr
85%
12%
3%
Total: 100%
u 6W (unitk
In
in/hr
ft3/sec
OK
OK
OK
OK
OK
OK
OK
;ss) -7e-ed; 14g Sol [s 'I?ePor+
Form SW401-Bioretention-Rev.7 Parts I and II. Design Summary. Page 1 of 2
Permit Number:
(to be provided by DWQ)
Basin Elevations
Temporary pool elevation 197.50 fmsl
Type of bioretention cell (answer "Y" to only one of the two
following questions):
Is this a grassed cell? Y (Y or N) OK
Is this a cell with trees/shrubs? N (Y or N)
Planting elevation (top of the mulch or grass sod layer) 196.5 fmsl
Depth of mulch 4 inches OK
Bottom of the planting media soil 194 fmsl
Planting media depth 2.5 ft
Depth of washed sand below planting media soil 0.33 ft
Are underdrains being installed? Y (Y or N)
How many clean out pipes are being installed? 6 OK
What factor of safety is used for sizing the underdrains? (See
5 OK
BMP Manual Section 12.3.6) _
Additional distance between the bottom of the planting media and
the bottom of the cell to account for underdrains _
Bottom of the cell required
SHWT elevation _
Distance from bottom to SHWT _
Planting Plan
Number of tree species
Number of shrub species
A (Y or N)
Y (Y or N) OK
Number of herbaceous groundcover species S o D
Additional Information
Does volume in excess of the design volume bypass the Y
bioretention cell?
%" dr- 1,331)
OK (44r 4 berwr4a/a 9rasS?
(Y or N) OK
Does volume in excess of the design volume flow evenly distributed ' ?o cr??C cQt p- '-o
through a vegetated filter? Iq (Y or N) (MtAs 6C;SIC6(? e cc,
e1e- t dtn_ cv?'S SQe plan See z,
What is the length of the vegetated filter? t?j f A-ft
Does the design use a level spreader to evenly distribute flow?
Is the BMP located at least 30 feet from surface waters (50 feet if
SA waters)?
Is the BMP localed at least 100 feet from water supply wells?
Are the vegetated side slopes equal to or less than 3:1?
Is the BMP located in a proposed drainage easement with access
to a public Right of Way (ROW)?
Inlet velocity (from tfeetffleritt-system) ?y?s; cc? ?ooSth
Is the area surrounding the cell likely to undergo development in
the future?
Are the slopes draining to the bioretention cell greater than 20%? N (Y or N) OK
Is the drainage area permanently stabilized? Y (Y or N) OK
Pretreatment Used
(Indicate Type Used with an "X" in the shaded cell)
Gravel and grass
(811nches gravel followed by 3-5 ft of grass)
Grassed swale
Forebay
Other
1 ft (&&0-1
192.67 fmsl
189 fmsl
3.67 ft OK
n
u
Y (Y or N) OK
Y (Y or N) OK
Y (Y or N) OK
$rJ ft/sec (V r8c{- c6nce.KT ? w ell Scher r V- 'F'D w`
bvass J?tP f r'n ecp
N (Y or N) OK 1?1 Milo
r /Pr
>J ?
?X
OK
Form SW401-Bioretention-Rev.7 Parts I and II. Design Summary Pane ) of 9
NCDWQ Required Items
Checklist
Permit No:
(to be assigned by DWQ)
iilz RE601 5011% 6' [iECKLIST _
Please indicate the page or plan sheet numbers where the supporting documentation can be found. An incomplete submittal package will
result in a request for additional information. This will delay final review and approval of the project. Initial in the space provided to
indicate the following design requirements have been met. If the applicant has designated an agent, the agent may initial below. If a
requirement has not been met, attach justification.
Pagel Plan
Initials Sheet No.
53 L,2 1. Plans (1" 50' or larger) of the entire site showing:
V' Design at ultimate build-out,
t41 - Off-site drainage (if applicable),
t/- Delineated drainage basins (include Rational C coefficient per basin),
ti'- Cell dimensions,
I/ - Pretreatment system, t=o bA
V' - High flow bypass system,B
1/- Maintenance access,
)/ - Recorded drainage easement and public right of way (ROW),
?- Clean out pipe locations,
?- Overflow device, and
t/ Boundaries of drainage easement.
910$ q • Z 2. Pjan details (1" = 30' or larger) for the bioretention cell showing:
// Cell dimensions
Pretreatment system, (?o
High flow bypass system, (C- E3 t?Maintenance access,
Recorded drainage easement and public right of way (ROW),
Design at ultimate build-out,
A?A - Off-site drainage (if applicable),
- Clean out pipe locations,
(/Overflow device, and
G? ,2
4J
3. Section view of the bioretention cell (1" = 20' or larger) showing:
- Side slopes, 3:1 or lower
l,'Underdrain system (if applicable), and
Bioretention cell layers [ground level and slope, pre-treatment, ponding depth, mulch depth, fill media
depth, washed sand, filter fabric (or choking stone if applicable), #57 stone, underdrains (if applicable),
SHWT level(s and overflow structure)
Boundaries of drainage easement.
- Indicate the P-Index between 10 and 30C-+-b 6e c ?v n?? ?j? ot'r (I 1D1 t5 re-FOk
_! --_
71 Jr'
4• A soils report that is based upon an actual field investigation, soil borings, and infiltration tests. The
results of the soils report must be verified in the field by DWQ, by completing & submitting the soils
investigation request form. County soil maps are not an acceptable source of soils information, All
elevations shall be in feet mean sea level (fmsl). Results of soils tests of both the planting soil and the in
situ soil must include:
Soil permeability, -TS V
Soil composition (% sand, % fines, % organic), and -'>]
P-index. -^TS D
5. A detailed planting plan (1" = 20' or larger) prepared by a qualified individual showing: C51"D
A variety of suitable species,
Sizes, spacing and locations of plantings,
Total quantity of each type of plant specified,
A planting detail,
The source nursery for the plants, and
Fertilizer and watering requirements to establish vegetation. lv'
6, An assurance that the installed system will meet design specifications upon initial operation once the
project is complete and the entire drainage area is stabilized.
G'?6 4.7- 7. A construction sequence that shows how the bioretention cell will be protected from sediment until the
entire drainage area is stabilized,
Gl?? 4 2 8• The supporting calculations (including underdrain calculations, if applicable). (A;&.1 su.PP ?2wt r?Po ?- ,JL1
C'W? f O r? 9. A copy of the signed and notarized inspection and maintenance (I&M) agreement. (tr a.
10. A copy of the deed restriction.
Form SW401-Bioretention-Rev.7 Part III, Page 1 of 1
NCDWQ Operations &
Maintenance Agreement
Permit Number:
(to be provided by DWQ)
Drainage Area Number:
Bioretenti.on Operation and Maintenance Agreement
I will keep a maintenance record on this BMP. This maintenance record will be kept in a
log in a known set location. Any deficient BW elements noted in the inspection will be
corrected, repaired or replaced immediately. These deficiencies can affect the integrity
of structures, safety of the public, and the removal efficiency of the BW.
Important operation and maintenance procedures:
- Immediately after the bioretention cell is established, the plants will be watered
twice weekly if needed until the plants become established (commonly six
weeks).
- Snow, mulch or any other material will NEVER be piled on the surface of the
bioretention cell.
Heavy equipment will NEVER be driven over the bioretention cell.
Special care will be taken to prevent sediment from entering the bioretention cell.
Once a year, a soil test of the soil media will be conducted.
After the bioretention cell is established, I will inspect it once a month and within 24
hours after every storm event greater than 1. cinches (or 1.5 inches if in a. Coastal
County). Records of operation and maintenance will be kept in a known set location
and will be available upon request.
Inspection activities shall be performed as follows. Any problems that are found shall
be repaired immediately.
BMP element: Potential problems: How I will remediate the problem:
The entire Bi O Trash/ debris is resent. Remove the trash/ debris,.
The perimeter of the Areas of bare soil and/or Regrade the soil if necessary to
bioretention cell erosive gullies have formed, remove the gully, and then plant a
ground cover and water until it is
established. Provide lime and a
one-time fertilizer application.
The inlet device: pipe, The pipe is clogged (if Unclog the pipe. Dispose of the
stone verge or swale applicable). sediment off-site.
The pipe is cracked or Replace the pipe.
otherwise damaged (if
applicable).
Erosion is occurring in the Regrade the Swale if necessary to
swale (if applicable). smooth it over and provide erosion
control devices such as reinforced
turf matting or riprap to avoid
future problems with erosion.
Stone verge is clogged or Remove sediment and clogged
covered in sediment (if stone and replace with clean stone.
applicable).
Form SW401-Bioretention O&M-Rev.3 Page 1 of 4
BMP element:
The pretreatment area
The bioretention cell:
vegetation
The bioretention cell:
soils and mulch
Potential problems:
Flow is bypassing
pretreatment area and/or
gullies have formed.
Sediment has accumulated to
a depth greater than three
inches.
Erosion has occurred,
Weeds are present,
Best professional practices
show that pruning is needed
to maintain optimal plant
health.
Plants are dead, diseased or
dying.
Tree stakes/wires are present
six months after planting.
Mulch is breaking down or
has floated away.
Soils and/or mulch are
clogged with sediment.
An annual soil test shows that
pH has dropped or heavy
metals have accumulated in
the soil media.
How I will remediate the
Regrade if necessary to route all
flow to the pretreatment area.
Restabilize the area after grading,
Search for the source of the
sediment and remedy the problem if
possible. Remove the sediment and
restabilize the pretreatment area,
Provide additional erosion
protection such as reinforced turf
matting or riprap if needed to
prevent future erosion problems.
Remove the weeds, preferably by
hand.
Prune according to best professional
practices.
Determine the source of the
problem;, soils, hydrology, disease,
etc. Remedy the problem and
replace plants. Provide a one-time
fertilizer application to establish the
ground cover if a soil test indicates
it is necessary. :
Remove tree stake/wires (which
can kill the tree if not removed).
Spot mulch if there are only random
void areas. Replace whole mulch
layer if necessary. Remove the
remaining much and replace with
triple shredded hard wood mulch at
a maximum depth of three inches.
Determine the extent of the clogging
- remove and replace either just the
top layers or the entire media as
needed. Dispose of the spoil in an
appropriate off-site location. Use
triple shredded hard wood mulch at
a maximum depth of three inches.
Search for the source of the
sediment and remedy the problem if
Dolomitic lime shall be applied as
recommended per the soil test and
toxic soils shall be removed,
disposed of properly and replaced
with new planting media.
Form 5W401-Bioretention O&M-Rev.3 Page 2 of 4
BMP element: Potential problems: How I will remediate the problem:
The underdrain system Clogging; has occurred. Wash out the underdrain system.
if applicable)
The drop inlet Clogging has occurred, Clean out the drop inlet. Dispose of
the sediment off -site.
The drop inlet is damaged Repair or re lace the drop inlet
The receiving water Erosion or other signs of Contact the NC Division of Water
damage have occurred at the Quality 401 Oversight Unit at 919-
outlet, 733-1786,
Form 5W401-Bioretention O&M-Rev.3 Page 3 of 4
Permit Number:
(to be provided by DWQ)
I acknowledge and agree by my signature below that I am responsible for the
performance of the maintenance procedures listed above. I agree to notify DWQ of any
problems with the system or prior to any changes to the system or responsible parry.
Project name: 5,GaY1 Lrz * rdLjg4j, c,[ C--drAV-LaPL5
BMP drainage area number:
Print name: -'A M%A M ARL-r I R J
L5 Ih3C_
Title: MZM15 Fes-
Address: GAIL- zF?t t?-t1-1. Nt.? , Z'7(ctC-?
Phone: x'11 S 0$ - e0s?
Signature: r
Date: 0 3142! -4cr;?q?'
Note: The legally responsible party should not be a homeowners association unless more than 50% of
the lots have been sold and a resident of the subdivision has been named the president
I, "(I Gll•( Resiei , a Notary Public for the State of
UrA aft4na, , County of iiah ath- , do hereby certify that
personally appeared before me this IVA
day of 1 v ? rrh QO , and a6cnowledge the due execution of the
forgoing bioretention maintenance requirements. Witness my hand and official seal,
/IV CQV'
SEAL
lie
A
My commission expires
Form SW401 Bioretendon I&M-Rev. 2 Page 4 of 4
Bio-Retention Design Inputs &
Summary of Results
Blo-Retention Input Data Sheet
Bio-Ret. Data Summary
Wet Detention Basin Data Summary
Water Quality Volume Calculations =_>
Total Drainage Area, At = 1.964 acres
Impervious Area, Ai = 1.51 acres
Impervious Fraction, la (Ai/At) = 0.77
Runoff Coefficient, Rv (0.05+0.9*lo) = 0.74
Design Storm Rainfall Depth, Rd = 1.00 in.
Water Quality Volume, WQv (3630*Rd*Rv*At) = 5289.64 cuff.
Cell Dimensions =_>
Ponding Depth of Water, DID (9-12") = 1.00 ft.
Required Surface Area, SAr (WQv/Pd) = 5289.64 sqft.
Surface Area Provided = 5411.00 sgft.
Average Length = 69 ft.
Average Width = 85 ft.
Media and Soils Summary =_>
Target Pollutant = Nitrogen
Planting Media Soil Composition (% By Weight) _
%Sand (By Weight) = 85 %
% Fines (By Weight) = 12 %,
% Organic Matter (By Weight) = 3 %
Estimated Drawdown Rafe, k = 1.00 in./hr
Drawdown time, Ponded Volume = 12.00 hrs.
Drawdown time, 24" Below Surface (48hrs. Max) = 36.00 hrs.
Cell Type Planting = Grassed
Topsoil Depth = 0.33' ft.
Minimum Media Depth = 2.00 ft.
Provided Media Depth = 2.50 ft.
Depth Washed Sand = 0.33 ft.
Depth #57 Stone = 1.33 ft.
Total Media Depth = 4.50 ft.
Critical Elevation Summary
=_>
Invert 8" Diversion Pipe (from CB20) = 196.50 ft.
Invert Forebay (18" Depth) = 195.00 ft.
.Cell Ponding Invert = 196.50 ft.
Overflow Riser Crest Elevation = 197.60 ft.
100-Yr Event WSE = 197.83 ft.
Bottom #57 Stone Layer = 192.00 ft.
Underdrain Design Summary =_>
Total Depth Ponding , Dpt = 3.50 ft.
Media Depth, Dm = 2.50 ft.
Permeable Flow Rate, Qk (k*Dpt/Dm) = 1.40 in./hr
Permeable Flow, Qp (Qk*Sap*Ift/12" 1hr/3600s) = 0.162 cfs
Safety Factor = 5.00
Underdrain Design Flow, Qdu = 0.81 cfs
Underdrain Slope, s = 0.005 ft/ft
Underdrain Manning's n-value, n = 0.011
Design Eq. (N*D = 16*(Qdu*n/sn0.5)n3/8)
NxD = 6.46
D = 8 in.
# 8" Drains = 1
# 4" Drains = 5
Cleanouts (1 per 1000sf) = 6
Bypass Orifice Design Summary =_>
1" Calculated Discharge, Q = 1.59 cfs
Discharge Coefficient, Cd = 0.60
Cross Sectional Area of Flow, A = 0.348 sqft.
Accel. Of Gravity, g = 0.162 ft/secn2
Driving Head, Ho = 0.86 ft
Bypass Design Size = 8.00 in.
Design Equation: Q = Cd*A*sgrt(2*g*Ho)
Qdesign = 1.57 In.
8" OK? Yes
Designer: Greg Brlckham
3/11/2009
2411 x 36" Drainage Area Map
(For Bio-Retention Drainage
Area Only)
100-Year Bio- Retention
Overflow Routing
(HydroCAD)
Drainage Area 1
CB
2P
)ass CB-20
Bio-Cell
Subcat Reach on Link
100-Yr Overflow Routing
Bio-Retention Routing
Prepared by {enter your company name here} Page 2
HydroCAD® 8.00 s/n 004300 © 2006 HydroCAD Software Solutions LLC 3/11/2009
Area Listing (all nodes)
Area (acres) CN Description (subcats)
0.454 89 <50% Grass cover, Poor, HSG D (1 S)
1.510 98 Paved parking & roofs (1S)
1.964
100-Yr Overflow Routing
Bio-Retention Routing Type 1124-hr 100-Year Rainfall=9.72"
Prepared by {enter your company name here} Page 3
HydroCAD® 8.00 s/n 004300 © 2006 HydroCAD Software Solutions LLC 3/11/2009
Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points
Runoff by SCS TR-20 method, UH=SCS
Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method
Subcatchment 1S: Drainage Area 1
Runoff Area=1.964 ac Runoff Depth>8.48"
Tc=5.0 min CN=96 Runoff=27.45 cfs 1.388 of
Pond 2P: Bypass CB-20 Peak EIev=203.57' Inflow=27.45 cfs 1.388 of
Primary=4.06 cfs 0.852 of Secondary=23.39 cfs 0.536 of Outflow=27.45 cfs 1.388 of
Pond 3P: Bio-Cell
Peak EIev=197.83' Storage=7,381 cf Inflow=4.06 cfs 0.852 of
Outflow=3.56 cfs 0.709 of
100-Yr Overflow Routing
Bio-Retention Routing Type// 24-hr 900-Year Rainfall=9.72"
Prepared by {enter your company name here} Page 4
HydroCAD® 8.00 s/n 004300 © 2006 HydroCAD Software Solutions LLC 3/11/2009
Subcatchment 1S: Drainage Area 1
Runoff = 27.45 cfs @ 11.95 hrs, Volume= 1.388 af, Depth> 8.48"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 100-Year Rainfall=9.72"
Area (ac) CN Description
1.510 98 Paved parking & roofs
0.454 89 <50% Grass cover, Poor, HSG D
1.964 96 Weighted Average
0.454 Pervious Area
1.510 Impervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry,
100-Yr Overflow Routing
Bio-Retention Routing Type 1124-hr 900-Year Rainfall=9.72"
Prepared by {enter your company name here} Page 5
HydroCAD® 8.00 s/n 004300 © 2006 HydroCAD Software Solutions LLC 3/11/2009
Pond 2P: Bypass CB-20
Inflow Area = 1.964 ac, Inflow Depth > 8.48" for 100-Year event
Inflow = 27.45 cfs @ 11.95 hrs, Volume= 1.388 of
Outflow = 27.45 cfs @ 11.95 hrs, Volume= 1.388 af, Atten= 0%, Lag= 0.0 min
Primary = 4.06 cfs @ 11.95 hrs, Volume= 0.852 of
Secondary = 23.39 cfs @ 11.95 hrs, Volume= 0.536 of
Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
Peak Elev= 203.57'@ 11.95 hrs
Device Routing Invert Outlet Devices
#1 Primary 196.80' 8.0" x 40.0' long 8" DIP CMP, square edge headwall, Ke= 0.500
Outlet Invert= 196,50' S=0.0075'/' Cc= 0.900 n=0.011
#2 Secondary 197.99' 18.0" x 85.0' long 18" RCP RCP, groove end projecting, Ke= 0.200
Outlet Invert= 192.00' S=0.0705'/' Cc= 0.900 n=0.013
Primary OutFlow Max=4.06 cfs @ 11.95 hrs HW=203.57' (Free Discharge)
t-1=8" DIP (Barrel Controls 4.06 cfs @ 11.64 fps)
Secondary OutFlow Max=23.38 cfs @ 11.95 hrs HW=203.57' (Free Discharge)
2=18" RCP (Inlet Controls 23.38 cfs @ 13.23 fps)
100-Yr Overflow Routing
Bio-Retention Routing Type// 24-hr 100-Year Rainfall=9.72"
Prepared by {enter your company name here) Page 6
HydroCAD® 8.00 s/n 004300 © 2006 HydroCAD Software Solutions LLC 3/11/2009
Stage-Discharge for Pond 2P: Bypass CB-20
Elevation Discharge Primary Secondary
(feet) (cfs) (cfs) (cfs)
196.80 0.00 0.00 0.00
196.90 0.03 0.03 0.00
197.00 0.12 0.12 0.00
197.10 0.26 0.26 0.00
197.20 0.43 0.43 0.00
197.30 0.62 0.62 0.00
197.40 0.81 0.81 0.00
197.50 0.99 0.99 0.00
197.60 1.14 1.14 0.00
197.70 1.17 1.17 0.00
197.80 1.28 1.28 0.00
197.90 1.37 1.37 0.00
198.00 1.47 1.47 0.00
198.10 1.63 1.55 0.08
198.20 1.93 1.63 0.29
198.30 2.33 1.71 0.62
198.40 2.85 1.78 1.07
198.50 3.46 1.85 1.61
198.60 4.17 1.92 2.24
198.70 4.94 1.99 2.95
198.80 5.78 2.05 3.73
198.90 6.67 2.11 4.55
199.00 7.59 2.17 5.41
199.10 8.52 2.23 6.29
199.20 9.44 2.29 7.15
199.30 10.32 2.35 7.97
199.40 11.11 2.40 8.71
199.50 11.72 2.45 9.27
199.60 12.37 2.50 9.86
199.70 12.98 2.56 10.42
199.80 13.56 2.61 10.95
199.90 14.11 2.65 11.46
200.00 14.64 2.70 11.94
200.10 15.15 2.75 12.40
200.20 15.65 2.80 12.85
200.30 16.13 2.84 13.28
200.40 16.59 2.89 13.70
200.50 17.04 2.93 14.11
200.60 17.48 2.98 14.51
200.70 17.91 3.02 14.89
200.80 18.33 3.06 15.27
200.90 18.73 3.10 15.63
201.00 19.13 3.14 15.99
201.10 19.52 3.18 16.34
201.20 19.91 3.22 16.68
201.30 20.28 3.26 17.02
201.40 20.65 3.30 17.35
201.50 21.01 3.34 17.67
201.60 21.37 3.38 17.99
201.70 21.72 3.42 18.30
201.80 22.06 3.46 18.61
Elevation Discharge Primary Secondary
(feet) (cfs) (cfs) (cfs)
201.90 22.40 3.49 18.91
202.00 22.73 3.53 19.20
202.10 23.06 3.57 19.50
202.20 23.39 3.60 19.78
202.30 23.71 3.64 20.07
202.40 24.02 3.67 20.35
202.50 24.33 3.71 20.62
202.60 24.64 3.74 20.90
202.70 24.94 3.78 21.17
202.80 25.24 3.81 21.43
202.90 25.54 3.84 21.69
203.00 25.83 3.88 21.95
203.10 26.12 3.91 22.21
203.20 26.41 3.94 22.46
203.30 26.69 3.98 22.71
203.40 26.97 4.01 22.96
203.50 27.25 4.04 23.20
100-Yr Overflow Routing
Bio-Retention Routing Type 11 24-hr 900-Year Rainfall=9.72"
Prepared by {enter your company name here} Page 7
HydroCAD® 8.00 s/n 004300 © 2006 HydroCAD Software Solutions LLC 3/11/2009
Elevation Storage
(feet) (cubic-feet)
196.80 0
196.90 0
197.00 0
197.10 0
197.20 0
197.30 0
197.40 0
197.50 0
197.60 0
197.70 0
197.80 0
197.90 0
198.00 0
198.10 0
198.20 0
198.30 0
198.40 0
198.50 0
198.60 0
198.70 0
198.80 0
198.90 0
199.00 0
199.10 0
199.20 0
199.30 0
199.40 0
199.50 0
199.60 0
199.70 0
199.80 0
199.90 0
200.00 0
200.10 0
200.20 0
200.30 0
200.40 0
200.50 0
200.60 0
200.70 0
200.80 0
200.90 0
201.00 0
201.10 0
201.20 0
201.30 0
201.40 0
201.50 0
201.60 0
201.70 0
201.80 0
Stage-Area-Storage for Pond 2P: Bypass CB-20
Elevation Storage
(feet) (cubic-feet)
201.90 0
202.00 0
202.10 0
202.20 0
202.30 0
202.40 0
202.50 0
202.60 0
202.70 0
202.80 0
202.90 0
203.00 0
203.10 0
203.20 0
203.30 0
203.40 0
203.50 0
100-Yr Overflow Routing
Bio-Retention Routing Type// 24-hr 100-Year Rainfall=9.72"
Prepared by {enter your company name here} Page 8
HydroCAD® 8.00 s/n 004300 © 2006 HydroCAD Software Solutions LLC 3/11/2009
Pond 3P: Bio-Cell
Inflow Area = 1.964 ac, Inflow Depth > 5.21" for 100-Year event
Inflow = 4.06 cfs @ 11.95 hrs, Volume= 0.852 of
Outflow = 3.56 cfs @ 12.00 hrs, Volume= 0.709 af, Atten= 12%, Lag= 2.9 min
Primary = 3.56 cfs @ 12.00 hrs, Volume= 0.709 of
Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
Peak Elev= 197.83' @ 12.00 hrs Surf.Area= 6,135 sf Storage= 7,381 cf
Plug-Flow detention time= 124.0 min calculated for 0.706 of (83% of inflow)
Center-of-Mass det. time= 62.3 min ( 801.1 - 738.8 )
Volume Invert Avail.Storage Storage Description
#1 196.50' 15,205 cf Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic-feet) (cubic-feet)
196.50 4,992 0 0
197.50 5,842 5,417 5,417
198.00 6,288 3,033 8,450
199.00 7,223 6,756 15,205
Device Routing Invert Outlet Devices
#1 Primary 192.00' 15.0" x 94.0' long Culvert RCP, groove end projecting, Ke= 0.200
Outlet Invert= 191.00' S=0.0106? Cc= 0.900 n=0.013
#2 Device 1 197.60' 2.50' x 2.50' Horiz. Orifice/Grate Limited to weir flow C= 0.600
Primary OutFlow Max=3.55 cfs @ 12.00 hrs HW=197.83' (Free Discharge)
LrCuivert (Passes 3.55 cfs of 12.63 cfs potential flow)
2=Orifice/Grate (Weir Controls 3.55 cfs @ 1.56 fps)
100-Yr Overflow Routing
Bio-Retention Routing Type 11 24-hr 100-Year Rainfall=9.72"
Prepared by {enter your company name here) Page 9
HvdroCAD® 8.00 s/n 004300 © 2006 HvdroCAD Software Solutions LLC 3/11/2009
Stage-Discharge for Pond 3P: Bio-Cell
Elevation Primary
(feet) (cfs)
196.50 0.00
196.52 0.00
196.54 0.00
196.56 0.00
196.58 0.00
196.60 0.00
196.62 0.00
196.64 0.00
196.66 0.00
196.68 0.00
196.70 0.00
196.72 0.00
196.74 0.00
196.76 0.00
196.78 0.00
196.80 0.00
196.82 0.00
196.84 0.00
196.86 0.00
196.88 0.00
196.90 0.00
196.92 0.00
196.94 0.00
196.96 0.00
196.98 0.00
197.00 0.00
197.02 0.00
197.04 0.00
197.06 0.00
197.08 0.00
197.10 0.00
197.12 0.00
197.14 0.00
197.16 0.00
197.18 0.00
197.20 0.00
197.22 0.00
197.24 0.00
197.26 0.00
197.28 0.00
197.30 0.00
197.32 0.00
197.34 0.00
197.36 0.00
197.38 0.00
197.40 0.00
197.42 0.00
197.44 0.00
197.46 0.00
197.48 0.00
197.50 0.00
Elevation Primary
(feet) (cfs)
197.52 0.00
197.54 0.00
197.56 0.00
197.58 0.00
197.60 0.00
197.62 0.09
197.64 0.26
197.66 0.48
197.68 0.74
197.70 1.03
197.72 1.36
197.74 1.71
197.76 2.09
197.78 2.50
197.80 2.92
197.82 3.37
197.84 3.84
197.86 4.34
197.88 4.84
197.90 5.37
197.92 5.92
197.94 6.48
197.96 7.06
197.98 7.66
198.00 8.27
198.02 8.90
198.04 9.54
198.06 10.20
198.08 10.87
198.10 11.56
198.12 12.26
198.14 12.98
198.16 13.00
198.18 13.02
198.20 13.04
198.22 13.07
198.24 13.09
198.26 13.11
198.28 13.13
198.30 13.15
198.32 13.17
198.34 13.20
198.36 13.22
198.38 13.24
198.40 13.26
198.42 13.28
198.44 13.30
198.46 13.33
198.48 13.35
198.50 13.37
198.52 13.39
Elevation Primary
(feet) (cfs)
198.54 13.41
198.56 13.43
198.58 13.45
198.60 13.47
198.62 13.50
198.64 13.52
198.66 13.54
198.68 13.56
198.70 13.58
198.72 13.60
198.74 13.62
198.76 13.64
198.78 13.66
198.80 13.69
198.82 13.71
198.84 13.73
198.86 13.75
198.88 13.77
198.90 13.79
198.92 13.81
198.94 13.83
198.96 13.85
198.98 13.87
199.00 13.89
100-Yr Overflow Routing
Bio-Retention Routing Type 11 24-hr 100-Year Rainfall=9.72"
Prepared by {enter your company name here} Page 10
HydroCAD® 8.00 s/n 004300 0 2006 HydroCAD Software Solutions LLC 3/11/2009
Stage-Area-Storage for Pond 3P: Bio-Cell
Elevation Surface Storage
(feet) (sq-ft) (cubic-feet)
196.50 4,992 0
196.55 5,035 251
196.60 5,077 503
196.65 5,120 758
196.70 5,162 1,015
196.75 5,205 1,275
196.80 5,247 1,536
196.85 5,289 1,799
196.90 5,332 2,065
196.95 5,374 2,332
197.00 5,417 2,602
197.05 5,460 2,874
197.10 5,502 3,148
197.15 5,545 3,424
197.20 5,587 3,703
197.25 5,630 3,983
197.30 5,672 4,266
197.35 5,714 4,550
197.40 5,757 4,837
197.45 5,799 5,126
197.50 5,842 5,417
197.55 5,887 5,710
197.60 5,931 6,006
197.65 5,976 6,303
197.70 6,020 6,603
197.75 6,065 6,905
197.80 6,110 7,210
197.85 6,154 7,516
197.90 6,199 7,825
197.95 6,243 8,136
198.00 6,288 8,450
198.05 6,335 8,765
198.10 6,381 9,083
198.15 6,428 9,403
198.20 6,475 9,726
198.25 6,522 10,051
198.30 6,569 10,378
198.35 6,615 10,708
198.40 6,662 11,040
198.45 6,709 11,374
198.50 6,756 11,710
198.55 6,802 12,049
198.60 6,849 12,391
198.65 6,896 12,734
198.70 6,942 13,080
198.75 6,989 13,428
198.80 7,036 13,779
198.85 7,083 14,132
198.90 7,130 14,487
198.95 7,176 14,845
199.00 7,223 15,205
Bioretention Sizing
PRE-DEVELOPMENT WATFRSHFn CHARACTERISTICS

Land Use/Cover Soil

Hydrologic
Group

Area (af)
Curve

Number

S (in) USE (01•S) for
Initial

Abstraction? (I
for yes)
Manual Initial

Abstraction (in) Initial

Abstraction
Used (in) Runoff

Depth
(in)
Runoff

Volume (cf)
0.00 0.00 1.00 0.00
forest B 12170 60 6.67 1 0.02 1.33 0.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 00 0.00
0.00 0.00 00 0.00
0.00 0.00 1.00 0.00
POST-DEVELOPMENT WATERSHED CHARACTERISTICS

and Use/Cover
Soil

Hydrologic
Group

rea (sf)

Curve

Number

(in) USE (01•S) for

Initial

Abstraction? {?
fer yes)

Manual Initial

Abstraction (In)
Initial

Abstraction
Used (In)
Runoff

Depth
(in)

Runoff

Volume (cf)
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
impervious surface B 9736 98 0.20 1 0.02 0.04 0.79 641.69
managed I landscaped B 2434 69 4.49 1 0.02 0.90 0.00 0.45
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0,00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
100 0.00 0 1.00 65.50
VVA i EK +i 1` i<AINFALLL AND ,os'r-DEVELOPMENT RUNOFF
First Flush Rain Depth (in) 1
otal Runoff Volume (co 707.64
[Total Runoff volume (ac4n) 0.19
Ayl fO'?`i "iP
Average BMP Depth (in) 12
Average BMP Depth (ft) 1
Fraction of Plant Cover 0.1
0.0181
786 ceft and B50 should match, adjust C38
otal Pre-Development Watershed Area (sf) 12170
otal Post-Development Watershed Area (sf) 12956
BMP Area of Wshed Area 6.07
&q : N csu 6 k9 cGrp&A hK JO
to?..
Bioretention Sizing
PRE-DEVELOPMENT WATERSHED CHARACTERISTICS

and Use/Cover
Soil

Hydrologic

Group

rea (sf)

Curve

Number

(in) USE (02-S) for

Initial

Abstraction? (l
for yes

Manual Initial

Abstraction (In)
Initial

Abstraction

Used (in)
Runoff

Depth

(in)

Runoff

Volume (cf)
0.00 0.00 1.00 0.00
forest B 47852 60 6.67 1 0.02 1.33 0.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
POST-DEVELOPMENT WATERSHED CHARACTERISTICS
Land Use/Cover Soil
Hydrologic
Group Area (sf) Curve
Number
FS(I USE (0.2`S) for
Initial
A
bstraction? (1 Manual Initial

Abstraction (In) Initial

Abstraction Used (in) Runoff

(in) Depth Runoff

Volume (cf)
0.00 1.00 0.00
0.00 1.00 0.00
0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
impervious surface B 38281 98 0.20 1 0.02 0.04 0.79 2523.06
managed I landscaped B 9571 69 4.49 1 0.02 0.90 0.00 1.79
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
MP - 100 0.00 0 1.00 257.67
WATER QUALITY RAINFo;LL , r G COST-DEVELOPMENT RUNOFF
First Flush Rain Depth (in) 1
otal Runoff Volume 2782.51 -

otal Runoff Volume (acin) 0.77
PRIMAR" BMW I 1ARACTL6 IS I iC;S
Average BMP Depth (in) 12
Average BMP Depth (ft) 1
Fraction of Plant Cover 0.1
0.0710

CALCULA7I0I4 CHECKS
otal Pre-Development Watershed Area (so 47852
otal Post-Development Watershed Area (so 50944
BMP Area of Wshed Area 6.07
?; r?csu ?k? d
1x44
Bioretention Sizing
PRE-DEVELOPMENT WATERSHED CHARACTERISTICS

and UselCover
Solt

Hydrologic
Group

rea (sf)

Curve
Number

(in) USE (02•S) for

Initial
Abstraction? 0
for YES)

Manual Initial
Abstraction (in)
Initial

Abstraction
Used (in)
Runoff

Depth
(in)

Runoff
Volume (cf)
0.00 0.00 1.00 0.00
forest B 21270 60 6.67 1 0.02 133 0.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
PncT.nFVFI nPMFNT WATERSHED CHARACTERISTICS

and Use/Cover
Soil

Hydrologic
Group

rea (sf)

Curve

Number

(in) USE (02'S) for

Initial

Abstr action? 41
:ar yes)

Manual Initial

Abstraction (In)
Initial

Abstraction
Used (in)
Runoff

Depth
(in)

Runoff

Volume (cf)
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
impervious surface B 17016 98 0.20 1 0.02 0.04 0.79 1121.50
managed / landscaped B 4254 69 4.49 1 0.02 0.90 0.00 0.79
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
BMW 100 0.00 0 1.00 114.50
VvA l: ai: I I ?, I o.lio, I ^,.),S I OiWVELOPMENT RUNOFF
First Flush Rain Depth (in) 1
otal Runoff Volume (cf) 1236.80 -
[Total Runoff Volume (ac-in) 0.34
NKIMAKY LSNIP UHAI<AL, I LKI61 IL.2+
Average BMP Depth (in) 12
Average BMP Depth (ft) 1
Fraction of Plant Cover 0.1
0.0315

CALCULATION CHECKS
Vote: cells C38 and B50 should match, adjust C38 ?.?.? A4` d csu 64 d¢panfroedf

W6
Bioretention Sizing
PRE-DEVELOPMENT WATERSHED CHARACTERISTICS

Land Use/Corer
Soil
Hydrologic
Group

Area (st)

Curve
Number

S (In) USE (0.2-S) for

Initial
Abstraction? (1
for yes)

Manual Initial
Abstraction (in)
Initial
Abstraction
Used (in)
Runoff
Depth
(in)

Runoff
Volume (cf)
0.00 0.00 1.00 0.00
forest B 47298 60 6.67 1 0.02 1.33 0.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
POST-DEVELOPMENT WATERSHED CHARACTERISTICS

Land Use/Corer
Soil
Hydrologic
Group

Area (sf)
Curve
Number

S (in) USE (0.2•S) for
Initial
Abstraction? f .
Manual Initial
Abstraction (In)
Initial
Abstraction
Used (in)
Runoff
Depth
(in)
Runoff
Volume (cf)
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
impervious surface B 37838 98 0.20 1 0.02 0.04 0.79 2493.86
managed / landscaped B 9460 69 4.49 1 0.02 0.90 0.00 1.77
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
BMP 100 0.00 0 1.00 254.67
Average BMP Depth (in) 12
Average BMP Depth (ft) 1
Fraction of Plant Cover 0.1
0.0702
3056 ?'
CALCULATION CHECKS
A4," NC?u -b-kg- c?j
ta?
Bioretention Sizing
PRE-DEVELOPMENT WATERSHED CHARACTERISTICS
--

Land Use/Cover
Soil

Hydrologic
Group

rea (sf)

Curve

Number

(in) USE (02•S) for

Initial

Abstraction? {1
fvr Yes)

Manual Initial

Abstraction (in)
Initial

Abstraction
Used (in)
Runoff

Depth
(in)

Runoff

Volume (G})
0.00 0.00 1.00 0.00
forest B 44302 60 6.67 1 0.02 1.33 0.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 00 0.00
POST-DEVELOPMENT WATERSHED CHARACTERISTICS

and Use/Cover
Soil

Hydrologic

Group

rea (s})
Curve

Number

(in) USE (02'S) for

Initlal

Abstractionl(1

a ywy).

Manual Initial

Abstraction (in)
Initial

Abstraction

Used (in)
Runoff

Depth

(in)

Runoff

Volume(cf)
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
impervious surface B 35441 98 0.20 1 0.02 0.04 0.79 2335.87
managed I landscaped B 8861 69 4.49 1 0.02 0.90 0.00 1.65
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
8MP 100 0.00 0 1.00 238.50
WATER U1jAl t1 ,, > wU MOST-DEVELOPMENT RUNOFF
First Flush Rain Depth (in) 1
otal Runoff Volume (cf) 2576.03
otal Runoff Volume (ac- n) 0.71
PRIMARY 3MP GHAk A(: i LK,;i i fC,
Average BMP Depth (in) 12
Average BMP Depth (ft) 1
Fraction of Plant Cover 0.1
0.0657
2862
CALCULATION CHECKS
Ad; HCSU SAE d,P?pptifnt¢d1
W7
Bioretention Sizing
PRE-DEVELOPMENT WATERSHED CHARACTERISTICS

and Use/Cover
Soil

Hydrologic
Group

rea (sf)
Curve

Number

(in) USE (02'S) for
Initial

Abstractlon7(1
for yes)
Manual Initial

Abstraction (In)
Initial

Abstraction
Used (In)
Runoff

Depth
(in)

Runoff
Volume (cf)
0.00 0.00 1.00 0.00
forest B 32109 60 6.67 1 0.02 1.33 0.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
POST-DEVELOPMENT WATERSHED CHARACTERISTICS

Land Use/Cover Soil
Hydrologic
Group
Area (sf)
Curve
Number
S(in) USE(0.2'S)for
Initial
Abstraction? (1
fur yss)
Manual Initial
Abstraction (In) Initial
Abstraction
Used (In) Runoff
Depth
(in) Runoff

Volume (cf)
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
impervious surface B 25687 98 0.20 1 0.02 0.04 0.79 1693.00
managed / landscaped B 6422 69 4.49 1 0.02 0.90 0.00 110
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
MP s -> 100 0.00 0 1.00 172.92
WATER QUALITY RA.iP*IF,ALL AND FGST-DEVELOPMENT RUNOFF
First Flush Rain Depth (in) 1
otal Runoff Volume (of) 1867.12
[Total Runoff Volume (ac4n) 0.51
PRIMARY E3MP ( HARAC7ERIS1ia_C
Average BMP Depth (in) 12
Average BMP Depth (ft) 1
Fraction of Plant Cover 0.1
0.0476
-T 1
2075 a"?t. , a , .era r iu r c; a _ ?.
GALCULA-i ION C:1iLCt<S
otal Pre-Development Watershed Area (sf) 32109
112tal Post-Development Watershed Area (so 34184
% BMP Area of Wshed Area 6.07
qb-#' NCScI ,874E e*4dM¢n#
1,04 8
Bioretention Sizing
DDC_n CVFI r%DUI=NT WATFRCHFn r WARArTFRICTICS

and Use/Cover
Soil

Hydrologic
Group

rea (si)

Curve

Number

(in) USE (D.YS) for

Initial

Abstraction? (1
for y esy

Manual Initial

Abstraction (in)
Initial

Abstraction
Used (in)
Runoff

Depth
(in)

Runoff

Volume (ci)
0.00 0.00 1.00 0.00
forest B 47854 60 6.67 1 0.02 1.33 0.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
POST-DEVELOPMENT WATERSHED CHARACTERISTICS

and UselCover
Soil

Hydrologic
Group

rea (sf)

Curve
Number

(in) USE (02•S) for

Initial
Abstraction? (1
fQr yes)

Manual Initial
Abstraction (in)
Initial

Abstraction
Used (in)
Runoff

Depth
(in)

Runoff
Volume (cf)
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
impervious surface B 38283 98 0.20 1 0.02 0.04 0.79 2523.19
managed I landscaped B 9571 69 4.49 1 0.02 0.90 0.00 1.79
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1,00 0.00
0.00 0.00 1.00 0.00
BMP guess 100 0.00 0 1.00 257.67
WATER QUALITY RAINF,'?LL AND POST-DEVELOPMENT RUNOFF
First Flush Rain Depth (in) 1
Vial Runoff Volume (cf) 2782.64+:
[Total Runoff volume (actin) 0.77
PRIMARY 8W& CHAikAG i tK; i i iu5
Average BMP Depth (in) 12
Average BMP Depth (ft) 1
Fraction of Plant Cover 0.1
0.0710
3092 ?oould r{. Ydjust C38
CALCULATION CHECKS
Vial Pre-Development Watershed Area (so 47854
otal Post-Development Watershed Area (sf) 50946
BMP Area of Wshed Area 6.07
(lp?- Ncsu ARE t{tpcitin[.+f
W 9
Bioretention Sizing
PRE-DEVELOPMENT WATERSHED CHARACTERISTICS

Land UselCover
Soli
Hydrologic
Group

Area (sf)
Curve
Number

S (In) USE (02'S) for
Initial
Abstraction? (1

Icr yes)
Manual Initial
Abstraction (in)
Initial
Abstraction
Used (In)
Runoff
Depth
(in)
Runoff
Volume (cf)
0.00 0.00 1.00 0.00
forest B 53028 60 6.67 1 0.02 1.33 0,00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
POST-DEVELOPMENT WATERSHED CHARACTFRISTICR
Land Use/Corer Soil
Hydrologic
Group Area (sf) Curve

Number USE (0.2'S) for
Initial
Abstraction? (1
fUf Y°.S) Manual Initial

Abstraction (In) Initial
Abstraction
Used (in) Runoff
Depth
(in) Runoff

Volume (cf)
0.00 1.00 0.00
0.00 1.00 0.00
N 0.00 1.00 0.00
0.00 1.00 0.00
no 1.00 0.00
impervious surface B 42422 98 1 0.02 0.04 0.79 2795.98
managed / landscaped B 10606 69 4.49 1 0.02 0.90 0.00 1.98
0.00 1.00 0.00
. 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 1.00 0.00
0.00 0.00 100 0.00
0.00 0.00 1.00 0.00
BMP 100 0.00 0 1 00 285.50
WATER CtWALI I ./ kAIN ALL AND POST-DEVELOPMENT RUNOFF
First Flush Rain Depth (in) 1
otal Runoff Volume (cf) 3083.46 [Total Runoff Volume (ac-in) 0.85 ~
F'RiNiARY ON& CFlAhAC I Et- ij6 f KS
Average BMP Depth (in) 12
Average BMP Depth (ft) 1
Fraction of Plant Cover 0.1
0.0787
3426 ??;. C: `tir1 tr.';S 4 wi!J 1r?:u4rj match, !iopj St f.38
-y
It?: rl ?Su ??E c?¢par?f?uN