HomeMy WebLinkAbout20060961 Ver 1_Stormwater Info_20070615 (65)~..
WITHERS RAVEN EL
WADE -Phase 2
Stormwater Management Report
WADE
Raleigh, North Carolina
Prepared For:
Wexford Developers, LLC
P.O. Box 3557
Cary, NC 27519
Prepared By:
WITHERS & RAVENEL, INC
iii MacKenan Drive
Cary, North Carolina 27511
May 2007
W&R Project No. 204467
-~,
? c, 6.-~ ,
r .,,ti a:
a .,~
_,~ : ~ .
~d'l' , 7 t , .~~
,~
~'~rsgf,u~a ;,
b r. t }~ ~
t :: p^.~~r~~(.'h1
~~>>~~u ~ u~~~~
`\~~~~`t H ~ ~ RQ ~~
~'
Q~ $ E'A ~'
• 1
i ' •NGI NG'~¢P~?'~~• /1
Stephanie A. Hall, P.E.
4o-WADE -Phase 2
Stormwater Management Report
Raleigh, North Carolina
INTRODUCTION
The purpose of this study is to document the stormwater management plan for Phase z of the
proposed development. The plan includes the design of two proposed best management practices
(BMPs 9A and 9B) in Phase z in order to treat stormwater runoff. The site is located in the Neuse
River Basin and all of the site drainage is received by two FEMA streams that run through the site,
Richland Creek and Medfield Creek Tributary, therefore making this phase of the project exempt
from the attenuation requirements for the 2-year and io-year design storms in the City of Raleigh.
The proposed BMPs for Phase 2 include a constructed wetland and a bioretention basin, designed
to draw down the first inch of runoff over a 2 to 5 day period and sized according to the Division of
Water Quality surface area requirements in order to achieve 85% Total Suspended Solids and 40%
total nitrogen reduction. The future phases of this development will employ the use of constructed
wetlands, bioretention areas, and/or wet detention basins followed by a forested filter strip in order
to meet Water Quality Certification #34oz in order to manage stormwater. These BMPs will be
designed and submitted at a later date.
METHODOLOGY
The stormwater study was conducted using the natural drainage features as depicted by the Wake
County aerial topographic information (z-ft contours), field survey data and proposed development
within the drainage areas.
qo-WADE - Phase z i W&R Project zo4467
Stormwater Management Report May zoo?
• 4o-WADE -Phase 2
Stormwater Management Report
Raleigh, North Carolina
•
• The scope of work included the following analyses:
Hydrolos;y
^ Simulation of the io-year and ioo-year rainfall events for the Raleigh area
^ Formulation of the io-year, and loo-year flood hydrographs for the proposed developed
. drainage area
• Hydraulic
^ Routing the io-year and ioo-year flood hydrographs for post development runoff through
• the proposed Stormwater wetland
The results of the hydrologic calculations are used in the hydraulic analyses. The hydraulic design
requires the development ofstage-storage and stage-discharge functions forthe wetland. The
• rainfall/runoff hydrographs, stage-storage and stage-discharge functions have been compiled to
create a routing computer simulation model using Haestad Methods PondPack vio.o software. This
PondPack model was then used to assess the impact of the peak discharges for the design rainfall
• events. The PondPack modeling results are provided as appendices to this report.
The bioretention is proceeded by a sputter box so that only the one inch/hour storm will be routed to
• the bioretention. Since the larger storms will be bypassed, the bioretention was not routed.
However, calculations including drawdown time were completed and are attached to this report.
• HYDROLOGY
The SCS Method was used to develop runoff hydrographs for the io-year and ioo-year storm events.
• NOAA Atlas iq rainfall data for Raleigh-Durham International Airport was used to determine the z4-
hourduration rainfall for the io-year and ioo-year storm events. This method requires three basic
parameters: a curve number (CN), time of concentration (t~, and drainage area.
Curve numbers were based on soil type and land use. Soil types were delineated from the Soil
Survey of Wake County, North Carolina (November i97o). Land use data was determined using aerial
• photography and the most recent site plans for the proposed site. The curve numbers used in this
study are listed in the appendix of this report.
• Times of concentration were estimated to have a time of concentration of 5 minutes to account for
shallow paved flow, and piping.
• HYDRAULICS
Computer simulated reservoir routing ofthe io-year, and ioo-year design storms utilized stage-
. storage and stage-discharge functions. Stage-storage functions were derived from the proposed
contours for the wet detention basins. Anon-linear regression relation for surface area versus
elevation was derived for the wetland. This relation estimates the incremental volume of the basin to
• the stage or elevation of the basins. Stage-discharge functions were developed to size the outlet
structures forthe wetlands.
•
•
•
CONCLUSIONS
Based on the routing study, the outlet proposed for the constructed wetland passes the ioo-year
storm with at least one foot of freeboard. The results are included in the appendix of this report.
Calculations forthe design of the bioretention basin are included in the appendix ofthis report as
4o-WADE -Phase z
Stormwater Management Report
W&R Project 204467
May zoo?
4o-WADE -Phase 2
Stormwater Management Report
Raleigh, North Carolina
well. The drainage area map on Sheet i of the appendix includes the outlet design for each BMP.
Planting schedules and more detailed design information is included on Construction Drawings
entitled "Wade Roadway Construction -Phase z" submitted with this report.
yo-WADE - Phase z 3 W&R Project zo4467
Stormwater Management Report May zoo?
Z
~~~'~~
,, .,\
~.
d I~
t:.
i
~,.
.,, w
y
`~
~.,
~ ~,
,. ., .~
-;J, ---
~,
w
~. °
.~
.w .
~;~ ~ ~,. ~
~,, ,
"''~« ~
~
~ ~
w
.
:a ,.
,~ .
.,
.~..
,•
1 il" ~~ i ~~ ": y ~ +Iw
~
°~ a~
~ c ,p
t
i t -',~, ~
. ~`
Mro*6'. b. .
.
..,. Mt . •
~~ ~
,~ .xx
b
F
~
~ .. A
N
~,
~ ~
M
..;
,~
•,
~~~ r .,;w .
_ ;
~
u,;;M , -
,~r ~ ~
~.~.~.,~. M .«..,. ..gyn.. .. . °, , ~
,., .~, ,~., ,..
_ ~ m.,. ;
;. _...
' ~
x
W
Z N K
d'
W; -
W
Q ~
N -
N
W
Z
~ _^ a
Q li
J ,`
N a~s
s
W
Wz=
I~
L W ~
r v
`Ji9
I..L
c~j
L
Q
^W
I..L
~..~..~
V
Q
Z
Q
N
W
~>
O
d'
e
~~ ~
n~ c a
i., ~l
3 im
o lu
BMP SIZING
CALC U LATI 0 N S
BMP 9A
Project Name: 40/WADE
City/State: Raleigh, NC
Project #: 204467
Date: 21-May-07
STORMWATER BMP #9A - BIORETENTION (85% TSS Removal 8~ 35% TN Removal)
Land Use Area
(ac) % IA Imp. Area
(ac)
Multi Family (B Soils) 4.29 65 2.8
Totals 4.29 2.8
Total % Impervious Surface Area = 65.0
First Flush Volume Calculation (1" of Rainfall)
Using the runoff volume calculations in the "Discreet Curve Number Method" as recommended by Dr. Bill Hunt, NC State University
5=(1000/CN)-10 S= Potential maximum Retention after runoff begins (inches)
R/O=(P-0.2S)Z/(P+0.8S) R/O= Runoff (inches)
P= Rainfall depth (in)
Impervious Areas (CN=98):
5= 0.20 inches
R/O = 0.79 inches
Runoff Volume = > V = 2.21 acre-inches
Pervious Areas (CN = 61):
5= 6.39 inches
R/O= 0.01 inches
Runoff Volume = > V = 0.02 acre-inches
Total runoff volume from 1-inch precipitation ( Sum of runoff volume from impervious and pervious areas):
Vt = 2.225 acre-inches
0.185 acre-ft
Storage Volume Required: 8075 cf
Water quality pool elevation = 370.50 feet
Storage volume provided** = 0.260 acre-ft
11340 cu. ft.
**Volume includes 6"ponding depth and first 24" within bioretention
Drawdown Time:
Underdrain Design:
Darcy's Law: Q=(2.3x10-'*K*A*(H/L)
Q=(2.3x10'*(1 in/h r)*(8100 sf)*(1 ft/ft))
Q=0.186 cfs
Time to Draw down Ponding area:
t = V/Q = 4050 cf/0.186 cfs =21,774 s
t=6 hrs
Time to Drawdown through first 24 inches of bioretention:
V (24") = 8100 sf * 0.45 *2 = 7290 cf
t = V/Q = 7290 cf/0.186 cfs = 39194 s
t = 10.9 hrs
Total Drawdown time = 17 hours
Manning's Equation:
D = 16*(0.186*0.011/O.Olo.s)sia
Minimum Diameter D=3.72"
Factor of Safety of 10 D = 16*(1.86*0.011/0.01os)3is
D = 8.82"
Use 2 - 4" smooth walled Plastic Pipe
BMP 9B
Project Name: 40/WADE Project #: 204467
City/State: Raleigh, NC Date: 21-May-07
Table 1.1 Surface Area to Drainage Area Ratio for Permanent Pool Sizing for 85% Pollutant
Ramnval Fffirianrv in tha Piartmnnt
Impervious
Cover Permanent Pool Depth (feet)
3.0 4.0 5.0 6.0 7.0 8.0 9.0
10 0.59 0.49 0.43 0.35 0.31 0.29 0.26
20 0.97 0.79 0.70 0.59 0.51 0.46 0.44
30 1.34 1.08 0.97 0.83 0.70 0.64 0.62
40 1.73 1.43 1.25 1.05 0.90 0.82 0.77
50 2.06 1.73 1.50 1.30 1.09 1.00 0.92
60 2.40 2.03 1.71 1.51 1.29 1.18 1.10
70 2.88 2.40 2.07 1.79 1.54 1.35 1.26
80 3.36 2.78 2.38 2.10 1.86 1.60 1.42
90 3.74 3.10 2.66 2.34 2.11 1.83 1.67
Source: NCUtNKNW(1 Stormwater t3est Management Practices, pg. S, April 1Y99
STORMWATER BMP #9B -WET POND (85% TSS Removal 8 25% TN Removal)
Land Use Area
(ac) % IA Imp. Area
(ac)
Multi Family 17.46 65 11.3
Totals 17.46 11.3
Total % Impervious Surface Area = 65.0
Normal Pool De th 3 4 5 6 7 8 9
SA/DA Ratio 2.64 2.10 1.92 1.67 1.37 1.27 1.25
Minimum Surface Area Re wired
Acres 0.46 0.37 0.33 0.29 0.24 0.22 0.22
Sq. Ft 20040.69 15933.68 14564.68 12701.31 10381.61 9659.08 9506.97
Surface Area of Permanent Pool:
Assumed depth = 3 feet
SA/DA ratio = 2.64 % From Table 1.1
Minimum pond surface area (SA) _ (DA * SA/DA ratio)/100
SA = 0.460 acres
20041 sq. ft.
Normal pool elevation = 380.50 feet
Surface area provided = 0.463 acres
20181 sq. ft.
First Flush Volume Calculation (1" of Rainfall)
Using the runoff volume calculations in the "Discreet Curve Number Method" as recommended by Dr. Bill Hun[, NC State University
5=(1000/CN)-10 S= Potential maximum Retention after runoff begins (inches)
R/O=(P-0.2S)Z/(P+0.8S) R/O= Runoff (incises)
P= Rainfall depth (in)
Impervious Areas (CN=98):
S= 0.20 inches
R/O= 0.79 inches
Runoff Volume = > V = 8.98 acre-inches
Pervious Areas (CN=61):
5= 6.39 inches
R/O= 0.01 inches
Runoff Volume = > V= 0.08 acre-inches
Total runoff volume from 1-inch precipitation (Sum of runoff volume from impervious and pervious areas):
Vt = 9.054 acre-inches
0.754 acre-k
32865 cf
Water quality pool elevation= 382.00 feet
Storage volume provided = 0.754 acre-ft
32865 cu. ft.
ROUTING
CALCULATIONS
To gmP9g
~~
N
O
~~~
BMP gB
o~
m
N
O
OUT 9B
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Table of Contents
Table of Contents
i.
********,r************* MASTER SUMMARY **********************
Watershed....... Master Network Summary ............. 1.01
****************** DESIGN STORMS SUMMARY *******************
RDU NOAA 19 Desi Design Storms ...................... 2.01
*****************r**** TC CALCULATIONS **************,r******
TO BMP 9B....... Tc Calcs ........................... 3.01
r**************,t***,r*r CN CALCULATIONS ************,r,r*******
TO BMP 9B....... Runoff CN-Area ..................... 4.01
r********************** POND VOLUMES r****************,r,r****
BMP 9B.......... Vol: Elev-Area ..................... 5.01
******************** OUTLET STRUCTURES *********************
Outlet BMP9B.... Outlet Input Data .................. 6.01
S/N: DOYXYWH3NLBE
Bentley PondPack (10.00.022.00) 8:24 AM
Withers & Ravenel
5/21/2007
Table of Contents
Composite Rating Curve ............. 6.04
S/N: DOYXYWH3NLBE Withers & Ravenel
Bentley PondPack (10.00.022.00) 8:24 AM 5/21/2007
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Table of Contents
Table of Contents (continued)
MASTER DESIGN STORM SUMMARY
Network Storm Collection: RDU NOAA 14 Desi
Total
Depth Rainfall
Return Event in Type RNF ID
10 4.9800 Time-Depth Curve RDU NOAA l0yr
1.00 7.3700 Time-Depth Curve RDU NOAA 100yr
ii
MASTER NETWORK SUMMARY
SCS Unit Hydrograph Method
(*Node=Outfall; +Node=Diversion;)
(Trun= HYG Truncation: Blank=None; L=Left; R=Rt; LR=Left&Rt)
Return HYG Vol
Node ID Type Event cu.ft Trun
------- --
------------
BMP 9B -----
IN ----
POND ------
10 ---
212316
BMP 9B IN POND 1.00 355402
BMP 9B OUT POND 10 210910
BMP 9B OUT POND 1.00 353943
*OUT 9B JCT 10 210909
*OUT 9B JCT 100 353992
TO BMP 9B AREA 10 212316
TO BMP 9B AREA 100 355402
Max
Qpeak Qpeak Max WSEL Pond Storage
hrs cfs ft cu.ft
12.1000 91.58
12.1000 123.03
12.2000 50.23 383.29 64560
12.2500 54.81 384.08 86098
12.2000 50.23
12.2500 54.81
12.1000 91.58
12.1000 123.03
S/N: DOYXYWH3NLBE
Bentley PondPack (10.00.022.00) 8:24 AM
Withers & Ravenel
5/21/2007
Type.... Master Network Summary Page 1.01
Name.... Watershed
File.... K:\04\04-460\09467-FortyWade\H-H\Stormwater\pondpack\40wade_PHASE2_rev.ppw
Title... Project Date: 10/19/2006
Project Engineer:
Project Title: Watershed
Project Comments:
DESIGN STORMS SUMMARY
Design Storm File,ID = RDU NOAA 19 Desi
Storm Tag Name = 10
Data Type, File, ID
Storm Frequency
Total Rainfall Depth
Duration Multiplier
Resulting Duration
Resulting Start Time
Time-Depth Curve RDU NOAA l0yr
10 yr
4.9800 in
1
23.9904 hrs
.0000 hrs Step= .0833 hrs End= 23.9904 hrs
Storm Tag Name = 100
Data Type, File, ID = Time-Depth Curve RDU NOAA 100yr
Storm Frequency = 100 yr
Total Rainfall. Depth= 7.3700 in
Duration Multiplier = 1
Resulting Duration = 23.9990 hrs
Resulting Start Time= .0000 hrs Step= .0833 hrs End= 23.9990 hrs
S/N: DOYXYWH3NLBE Withers & Ravenel
Bentley PondPack (10.00.022.00) 8:24 AM 5/21/2007
Type.... Design Storms
Name.... RDU NOAA 14 Desi
Page 2.01
File.... K:\09\09-460\04467-FortyWade\H-H\Stormwater\pondpack\40wade_PHASE2_rev.ppw
........................................................................
........................................................................
TIME OF CONCENTRATION CALCULATOR
........................................................................
........................................................................
Segment #1: Tc: User Defined
Segment #1 Time: .0833 hrs
-------------------------
-------------------------
Total Tc: .0833 hrs
Calculated Tc < Min,Tc:
Use Minimum Tc...
Use Tc = .0833 hrs
-------------------------
S/N: DOYXYWH3NLBE Withers & Ravenel
Bentley PondPack (10.00.022.00) 8:24 AM 5/21./2007
Type.... Tc Calcs
Name.... TO BMP 9B
Page 3.01
Fi1e.... K:\04\04-460\04467-FortyWade\H-H\Stormwater\pondpack\40wade_PHASE2_rev.ppw
Tc Equations used...
___= User Defined =------------------------------------------------
Tc = Value entered by user
Where: Tc = Time of concentration
S/N: DOYXYWH3NLBE Withers & Ravenel
Bentley PondPack (10.00.022.00) 8:24 AM 5/21/2007
Type.... Tc Calcs
Name.... TO BMP 9B
Page 3.02
File.... K:\04\04-460\09967-Fortywade\H-H\Stormwater\pondpack\40wade_PHASE2_rev.ppw
RUNOFF CURVE NUMBER DATA
..........................................................................
..........................................................................
Impervious
Area Adjustment Adjusted
Soil./Surface Description CN acres oC oUC CN
Residential Districts - 1/8 acre (t 85 17.960 85.00
COMPOSITE AREA & WEIGHTED CN ---> 17.460 85.00 (85)
...........................................................................
...........................................................................
S/N: DOYXYWH3NLBE Withers & Ravenel
Bentley PondPack (10.00.022.00) 8:29 AM 5/21/2007
Type.... Runoff CN-Area
Name.... TO BMP 9B
Page 9.01
File.... K:\04\04-460\04967-FortyWade\H-H\Stormwater\pondpack\90wade_PHASE2-rev.ppw
Elevation Planimeter Area Al+A2+sgr(A1*A2) Volume Volume Sum
(ft) (sq.in) (sq.ft) (sq.ft) (cu.ft) (cu.ft)
380.50 ----- 20181 0 0 0
381..00 21235 62118 10353 1.0353
382.00 ----- 23393 66916 22305 32658
383.00 25603 73969 24990 57148
384.00 ----- 27866 80180 26727 83875
385.00 ----- 30142 86990 28997 17.2871.
POND VOLUME EQUATIONS
* Incremental volume computed by the Conic Method for Reservoir Volumes.
Volume = (1/3) * (EL2-EL1) * (Areal + Areal + sq.rt.(Areal*Area2))
where: ELl, EL2 = Lower and upper elevations of the increment.
Areal,Area2 = Areas computed for EL1, EL2, respectively
Volume = Incremental volume between ELl and. EL2
S/N: DOYXYWH3NLBE Withers & Ravenel
Bentley PondPack (1.0.00.022.00) 8:24 AM 5/21/2007
~_
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Type.... Vol: Elev-Area Page 5.01
Name.... BMP 9B
File.... K:\09\04-460\04467-FortyWade\H-H\Stormwater\pondpack\40wade_PHASE2_rev.ppw
REQUESTED POND WS ELEVATIONS:
Min. Elev.= 380.50 ft
Increment = .05 ft
Max. Elev.= 385.00 ft
OUTLET CONNECTIVITY
---> Forward Flow Only (Upstream to DnStream)
<--- Reverse Flow Only (DnStream to Upstream)
<---> Forward and Reverse Both Allowed
Structure No. Outfall E1, ft E2, ft
Inlet Box RO ---> CO 382.000 385.000
Orifice-Circular 00 ---> CO 380.500 385.000
Culvert-Circular CO ---> TW 377.500 385.000
TW SETUP, DS Channel
S/N: DOYXYWH3NLBE
Bentley PondPack (10.00.022.00) 8:24 AM
Withers & Ravenel
5/21/2007
Type.... Outlet Input Data
Name.... Outlet BMP9B
Page 6.01
File.... K:\04\04-460\04467-FortyWade\H-H\Stormwater\pondpack\40wade PHASE2 rev.ppw
OUTLET STRUCTURE INPUT DATA
Structure ID = RO
Structure Type =
------------------- Inlet Box
-----------------
# of Openings = 1
Invert Elev, = 382.00 ft
Orifice Area = 25.0000 sq.ft
Orifice Coeff. _ .600
Weir Length = 20.00 ft
Weir Coeff. = 3.100
K, Reverse = 1.000
Mannings n = .0000
Kev,Charged Riser = .000
Weir Submergence = No
Structure ID = 00
Structure Type = Orifice-Circular
# of Openings = 1
Invert Elev. = 380.50 ft
Diameter = 3.00 in
Orifice Coeff. _ .600
S/N: DOYXYWH3NLBE
Bentley PondPack (10.00.022.00) 8:24 AM
Withers & Ravenel
5/21/2007
Type.... Outlet Input Data
Name.... Outlet BMP9B
Page 6.02
File.... K:\09\04-460\09967-FortyWade\H-H\Stormwater\pondpack\40wade PHASE2 rev.ppw
OUTLET STRUCTURE INPUT DATA
Structure ID = CO
Structure Type = Culvert-Circular
No. Barrels = 1
Barrel Diameter = 30.00 in
Upstream Invert = 377.50 ft
Dnstream Invert. = 375.00 ft
Horiz. Length = 55.00 ft
Barrel Length = 55.06 ft
Barrel Slope = .09595 ft/ft
OUTLET CONTROL DATA...
Mannings n = .0130
Ke = .5000
Kb = .009217
Kr = .5000
HW Convergence = .001
INLET CONTROL DATA...
Equati on form = 1
Inlet Control. K = .0098
Inlet Control M = 2.0000
Inlet Control. c = .03980
Inlet Control Y = .6700
T1 ratio (HW/D) = 1.138
T2 ratio (HW/D) = 1.284
Slope Factor = -.500
(forward. entrance loss)
(per ft of full flow)
(reverse entrance loss)
+/- ft
Use unsubmerged inlet control Form 1 equ. below T1 elev.
Use submerged inlet control. Form 1 equ. above T2 elev.
In transition zone between unsubmerged and submerged inlet control,
interpolate between flows at T1 & T2...
At T1 Elev = 380.34 ft ---> Flow = 27.16 cfs
At T2 Elev = 380.71 ft ---> Flow = 31.05 cfs
Structure ID = TW
Structure Type = TW SETUP, DS Channel
------------------------------------
FREE OUTFACE CONDITIONS SPECIFIED
CONVERGENCE TOLERANCES.
Maximum Iterations=
Min. TW tolerance =
Max. TW tolerance =
Min. HW tolerance =
Max. HW tolerance =
Min. Q tolerance =
Max. Q tolerance =
S/N: DOYXYWH3NLBE
Bentley PondPack (10.00.022.00)
40
.Ol ft
.O1 ft
.O1 ft
.O1 ft
.00 cfs
.00 cfs
8:24 AM
Withers & Ravenel
5/21/2007
Type.... Outlet Input Data
Name.... Outlet BMP9B
Page 6.03
File.... K:\04\04-460\04467-FortyWade\H-H\Stormwater\pondpack\40wade PHASE2 rev.ppw
***** COMPOSITE OUTFLOW SUMMARY ****
WS Elev, Total Q Notes
-- ------ -- Converge ------- ---- -- ------------
Elev. Q TW El ev Error
ft cfs ft +/-ft Contrib utin g Structures
380.50 .00 Free Outfall (no Q: RO,OO ,CO)
380.55 .00 Free Outfall OO,CO (no Q: RO)
380.60 .Ol Free Outfall OO,CO (no Q: RO)
380.65 .03 Free Outfall OO,CO (no Q: RO)
380.70 .06 Free Outfall OO,CO (no Q: RO)
380.75 .08 Free Outfall OO,CO (no Q: RO)
380.80 .10 Free Outfall OO,CO (no Q: RO)
380.85 .11 Free Outfall OO,CO (no Q: RO)
380.90 .12 Free Outfall OO,CO (no Q: RO)
380.95 .14 Free Outfall OO,CO (no Q: RO)
381.00 .15 Free Outfall OO,CO (no Q: RO)
381.05 .15 Free Outfall OO,CO (no Q: RO)
381.10 .16 Free Outfall OO,CO (no Q: RO)
381.15 .17 Free Outfall OO,CO (no Q: RO)
381.20 .18 Free Outfall OO,CO (no Q: RO)
381.25 .19 Free Outfall OO,CO (no Q: RO)
381.30 .19 Free Outfall OO,CO (no Q: RO)
381.35 .20 Free Outfall OO,CO (no Q: RO)
381.40 .21 Free Outfall OO,CO (no Q: RO)
381.45 .21 Free Outfall OO,CO (no Q: RO)
381.50 .22 Free Outfall OO,CO (no Q: RO)
381.55 .23 Free Outfall OO,CO (nc Q: RO)
381.60 .23 Free Outfall OO,CO (no Q: RO)
381.65 .24 Free Outfall OO,CO (no Q: RO)
381.70 .25 Free Outfall OO,CO (no Q: RO)
381.75 .25 Free Outfall OO,CO (no Q: RO)
381.80 .26 Free Outfall OO,CO (no Q: RO)
381.85 .26 Free Outfall OO,CO (no Q: RO)
381.90 .27 Free Outfall OO,CO (no Q: RO)
381.95 .27 Free Outfall OO,CO (no Q: RO)
382.00 .28 Free Outfall OO,CO (no Q: RO)
382.05 .97 Free Outfall RO,OO,C O
382.10 2.25 Free Outfall RO,OO,C O
382.15 3.89 Free Outfall RO,OO,C O
382.20 5.84 Free Outfall RO,OO,C O
382.25 8.05 Free Outfall RO,OO,C O
382.30 10.49 Free Outfall RO,OO,C O
382.35 13.15 Free Outfall RO,OO,C O
S/N: DOYXYWH3NLBE Withers & Ravenel
Bentley PondPack (10.00.022.00) 8:24 AM 5/21/2007
Type.... Composite Rating Curve
Name.... Outlet BMP9B
Page 6.04
File.... K:\04\09-960\04467-FOrtyWade\H-H\Stormwater\pondpack\40wade_PHASE2_rev.ppw
***** COMPOSITE OUTFLOW SUMMARY ****
WS E1ev, Total Q Notes
-------- - ------ -- Converge ---- - ------------
Elev. Q TW El ev Error
ft cfs ft +/-ft Contributing Structures
382.40 16.00 Free Outfall RO,OO,CO
382.45 19.03 Free Outfall RO,OO,CO
382.50 22.23 Free Outfall RO,OO,CO
382.55 25.60 Free Outfall RO,OO,CO
382.60 29.13 Free Outfall RO,OO,CO
382.65 32.78 Free Outfall RO,OO,CO
382.70 36.56 Free Outfall RO,OO,CO
382.75 40.47 Free Outfall RO,OO,CO
382.80 44.48 Free Outfall RO,OO,CO
382.85 47.53 Free Outfall RO,OO,CO
382.90 97.85 Free Outfall RO,OO,CO
382.95 48.16 Free Outfall RO,CO (no Q: 00)
383.00 48.48 Free Outfall RO,CO (no Q: 00)
383.05 48.79 Free Outfall RO,CO (no Q: 00)
383.10 49.10 Free Outfall RO,OO,CO
383.15 99.40 Free Outfall RO,OO,CO
383.20 49.71 Free Outfall RO,CO (no Q: 00)
383.25 50.02 Free Outfall RO,CO (no Q: 00)
383.30 50.32 Free Outfall RO,CO (no Q: 00)
383.35 50.62 Free Outfall RO,OO,CO
383.40 50.91 Free Outfall RO,CO (no Q: 00)
383.45 51.21 Free Outfall RO,CO (no Q: 00)
383.50 51.51 Free Outfall RO,CO (no Q: 00)
383.55 51.80 Free Outfall RO,CO (no Q: 00)
383.60 52.09 Free Outfall RO,CO (no Q: 00)
383.65 52.38 Free Outfall RO,CO (no Q: 00)
383.70 52.67 Free Outfall RO,CO (no Q: 00)
383.75 52.95 Free Outfall RO,CO (no Q: 00)
383.80 53.24 Free Outfall RO,CO (no Q: 00)
383.85 53.52 Free Outfall RO,CO (no Q: 00)
383.90 53.81 Free Outfall RO,CO (no Q: 00)
383.95 54.09 Free Outfall RO,CO (no Q: 00)
384.00 54.37 Free Outfall RO,CO (no Q: 00)
384.05 54.65 Free Outfall RO,CO (no Q: 00)
384.10 54.92 Free Outfall RO,CO (no Q: 00)
384.15 55.19 Free Outfall RO,CO (no Q: 00)
384.20 55.47 Free Outfall RO,CO (no Q: 00)
384.25 55.74 Free Outfall RO,CO (no Q: 00)
S/N: DOYXYWH3NLBE
Bentley PondPack (10.00.022.00) 8:24 AM
Withers & Ravenel
5/21/2007
Type.... Composite Rating Curve
Name.... Outlet BMP9B
Page 6.05
File.... K:\09\04-460\04967-FortyWade\H-H\Stormwater\pondpack\40wade PHASE2 rev.ppw
***** COMPOSITE OUTFLOW SUMMARY ****
WS Elev, Total Q
Elev. Q
ft cfs
384.30 56.01
384.35 56.28
384.90 56.55
384.45 56.82
384.50 57.08
384.55 57.35
384.60 57.61
384.65 57.88
384.70 58.13
384.75 58.39
384.80 58.65
384.85 58.91
389.90 59.16
389.95 59.42
385.00 59.68
Notes
------ -- Converge ------ ---- --- -----
TW El ev Error
ft +/-ft Contri buting Structures
Free Outfall RO,CO (no Q: 00)
Free Outfall RO,CO (no Q: 00)
Free Outfall RO,CO (no Q: 00)
Free Outfall RO,CO (no Q: 00)
Free Outfall RO,CO (no Q: 00)
Free Outfall RO,CO (no Q: 00)
Free Outfall RO,CO (no Q: 00)
Free Outfall RO,CO (no Q: 00)
Free Outfall RO,CO (no Q: 00)
Free Outfall RO,CO (no Q: 00)
Free Outfall RO,CO (no Q: 00)
Free Outfall RO,CO (no Q: 00)
Free Outfall RO,CO (no Q: 00)
Free Outfall RO,CO (no Q: 00)
Free Outfall RO,CO (no Q: 00)
S/N: DOYXYWH3NLBE Withers & Ravenel
Bentley PondPack (10.00.022.00) 8:24 AM 5/21/2007