20110446 Ver 1_Stormwater Plans_20110406

201 10446
STORM WATER MANAGEMENT
CALCULATIONS
FOR
COTTONWOOD VILLAGE
PHASE I
LINCOLN COUNTY, NORTH CAROLINA
April 1, 2011
PREPARED BY:
?.WSP•SELLS
F-0891
128 Overhill Drive, Suite 105
Mooresville, NC 28117
Phone: [phone]
Fax: [phone]
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its 969

' PROJECT NARRATIVE
The Cottonwood Village Phase 1 project in Lincoln County, NC will consist of the extension of an
' existing road to serve the multiple lots proposed for the development. Phase 1 construction will
consist of a stream crossing and approximately 2.28 acres of disturbance.
A 404 permit (US Army Corp. of Engineers) has been approved (2010-01950, Nationwide permit
39, December 8, 2010).
The enclosed storm water management plan includes the entire Cottonwood Village development
and shows the construction of Pond 1, which will be constructed prior to the entire site reaching 24%
imperviousness. Pond 1 takes into account Phase 1, Phase 2, and part of Phase 3 (apartments that
will drain to Pond 1 in the future) of Cottonwood Village. The storm water management plan also
shows the location of Pond 2 which will need to be constructed with Phase 3 and Phase 4 of the
project.
The proposed BMP(s) are denoted as Pond 1 and Pond 2. The BMP(s) are designed in accordance
' with the North Carolina BMP Manual (2007 edition). Pond 1 is designed for 85% TSS removal with
a permanent pool minimum average depth of 4 feet. Pond 2 will need to be designed with Phase 3
and Phase 4 of the project.
' The hydrologic calculations include pre and post discharge rates for the 1-yr, 10-yr, and 50-yr 24
hour events. These calculations are based upon SCS TR20 method using HydroCAD computer
' modeling. The water quality drawdown is based upon the 1-inch storm event per the BMP
guidelines.
As shown in the calculations, the post development discharge rates are below predevelopment
discharge rates for the 1-yr storm event. The emergency spillway is sized for the 50-yr storm event.
' The BMP(s) will be constructed after the site construction is completed and the site is stabilized in
accordance with the erosion and sediment control plan. Following construction of the BMP(s) and
establishment of vegetation, the BMP(s) will be maintained in accordance with the Operations and
Maintenance Agreements included in this Plan.

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1
NCDENR FORMS
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Permit No.
(to be provided by DWQ)
O?O? W A TF9pG
o
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
401 CERTIFICATION APPLICATION FORM
WET DETENTION BASIN SUPPLEMENT
This form must be filled out, printed and submitted.
The Required Items Checklist (Part 111) must be printed, filled out and submitted along with all of the required information.
I. PROJECT INFORMATION
Project name CottonWood Village
Contact person Jonathan Carter
Phone number 704-662-0100
Date 3129/2011
Drainage area number 1
II. DESIGN INFORMATION
Site Characteristics
Drainage area 710,323 ftz
Impervious area, post-development 409,316 ftZ
% impervious 57.62 %
Design rainfall depth 1.0 in
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
Peak Flow Calculations
Is the pre/post control of the lyr 24hr storm peak flow required?
1-yr, 24-hr rainfall depth
Rational C, pre-development
Rational C, post-development
Rainfall intensity: 1-yr, 24-hr storm
Pre-development 1-yr, 24-hr peak flow
Post-development 1-yr, 24-hr peak flow
Pre/Post 1-yr, 24-hr peak flow control
Elevations
Temporary pool elevation
Permanent pool elevation
SHWT elevation (approx. at the perm. pool elevation)
Top of 1 Oft vegetated shelf elevation
Bottom of 1Oft vegetated shelf elevation
Sediment cleanout, top elevation (bottom of pond)
Sediment cleanout, bottom elevation
Sediment storage provided
Is there additional volume stored above the state-required temp, pool?
Elevation of the top of the additional volume
Form SW401-Wet Detention Basin-Rev.8-9/17/09
33,845 ft3 OK
39,196 ft3 OK, volume provided is equal to or in excess of volume required.
ft3
ft3
ft3
ft3
ft3
Y (Y or N)
3.0 in
(unitless)
(unitless)
in/hr
3.35 ft3/sec
3.23 ft3/sec
-0.12 ft3/sec
716.00 fmsl
712.00 fmsl
705.00 fmsl
712.50 fmsl
711.50 fmsl
709.00 fmsl
707.00 fmsl
2.00 ft
y (Y or N)
716.0 fmsl OK
Parts I. & II. Design Summary, Page 1 of 2

Permit No.
(to be provided by DWQ)

II. DESIGN INFORMATION
Surface Areas
Area, temporary pool 26,876 ft2
' Area REQUIRED, permanent pool 12,289 ftZ
SA/DA ratio 1.73 (unitless)
Area PROVIDED, permanent pool, Apen-pod 16,289 e
Area, bottom of 111 vegetated shelf, Abd shelf
Area, sediment cleanout, top elevation (bottom of pond), Abot_pond 9,675 ft'
5,959 ft'
Volumes
Volume, temporary pool 39,196 ft3
' Volume, permanent pool, Vp,.-p.ol 52,357 ft3
Volume, forebay (sum of forebays if more than one forebay) 11,092 ft3
Forebay % of permanent pool volume 21.2% %
SA/DA Table Data
' Design TSS removal 85 %
Coastal SAIDA Table Used? n (Y or N)
Mountain/Piedmont SAIDA Table Used? y (Y or N)
SAIDA ratio 1.73 (unitless)
Average depth (used in SAIDA table):
Calculation option 1 used? (See Figure 10-2b) n (Y or N)
Volume, permanent pool, Vperm,pool 52,357 ft'
Area provided, permanent pool, Aperm-pool 16,289 ft'
' Average depth calculated It
Average depth used in SAIDA, d.„ (Round to nearest 0.5ft) It
Calculation option 2 used? (See Figure 10-2b) (Y or N)
' Area provided, permanent pool, Apermyooi 16,289 e
Area, bottom of 10ftvegetated shelf, Abot shelf 9,675 ft'
Area, sediment cleanout, top elevation (bottom of pond), Abol-pond 5,959 ftZ
"Depth" (distance b/w bottom of 1 Oft shelf and top of sediment) 2.50 It
Average depth calculated 4.40 It
Average depth used in SAW, day, (Round to nearest 0.5ft) 4.5 ft
Drawdown Calculations
Drawdown through orifice?
Diameter of orifice (if circular)
Area of orifice (if-non-circular)
Coefficient of discharge (CD)
Driving head (Ho)
Drawdown through weir?
W fficie
Coefficient of discharge (CW)
Length of weir (L)
Driving head (H)
Pre-development 1-yr, 24-hr peak flow
Post-development 1-yr, 24-hr peak flow
Storage volume discharge rate (through discharge orifice or weir)
Storage volume drawdown time
' Additional Information
Vegetated side slopes
Vegetated shelf slope
Vegetated shelf width
Length of flowpath to width ratio
Length to width ratio
Trash rack for overflow & orifice?
Freeboard provided
Vegetated filter provided?
Recorded drainage easement provided?
Capures all runoff at ultimate build-out?
Drain mechanism for maintenance or emergencies is:
Form SW401-Wet Detention Basin-Rev.8-9/17/09

y (Y or N)
2.00 in
in2
0.60 (unitless)
2.00 It
n (Y or N)
(unitless)
(unitless)
It
It
3.35 ft3/sec
0.60 ft3/sec
0.15 ft3/sec
3.10 days
OK
OK
OK
Need 3 ft min.
OK
OK
OK, draws down in 2-5 days.
3 :1 OK
10 :1 OK
10.0 ft OK
3 :1 OK
2.0 :1 OK
y (Y or N) OK
1.0 It OK
y (Y or N) OK
y (Y or N) OK
y (Y or N) OK
Concrete spillway
Parts I. & II. Design Summary, Page 2 of 2

0

RAINFALL DATA

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Precipitation Frequency Data Server Page 1 of 4
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' POINT PRECIPITATION,.
FREQUENCY ESTIMATES
FROM NOAA ATLAS 14 'k,
LINCOLNTON 4 W, NORTH CAROLINA (31-4996) 35.4667 N 81.3333 W 898 feet
from "Precipitation-Frequency Atlas of the United States" NOAA Atlas 14, Volume 2, Version 3
G.M. Bonnin, D. Martin, B. Lin, T. Parzybok, M.Yekta, and D. Riley
NOAA, National Weather Service, Silver Spring, Maryland, 2004
Extracted: Mon Dec 13 2010 -ir Confidence Limits Seasonality Related Info 11 GIS data 11 Maps 11 Docs Return to state
ARI' S 10 15 30 60 120
3 hr
6 hr 12
24 hr
48 hr
4 day
7 day 10 20 30 45 60
(years) min min min min min min

0.39 0.62 0.78 1.06 1.33 1.54 1.65

2.03 hr

2.47 day da da da da
? ?
2.98 3.54 3.97 4.59 5.24 7.01 8.59 10.84 12.92
0 0.46 0.73 0.92 1.28 1.60 1.87 2.00 2.44 2.98 3.60 4.26 4.77 5.49 6.24 8.28 10.11 12.69 15.07
0.54 0.87 1.10 1.56 2.00 2.35 2.51 3.06 3.73 4.54 5.33 5.89 6.68 7.50 9.78 11.73 14.45 16.99
10 0.60 0.96 1.22 1.77 2.30 2.72 2.93 3.56 4.34 5.27 6.17 6.78 7.63 8.48 10.95 12.97 15.79 18.46
25 0.68 1.08 1.37 2.03 2.70 3.24 3.51 4.27 5.19 6.29 7.32 7.99 8.92 9.79 12.51 14.59 17.52 20.35
50 0.73 1.17 1.48 2.23 3.02 3.65 3.99 4.86 5.89 7.09 8.23 8.94 9.94 10.81 13.73 15.83 18.83 21.77
100 0.79 1.25 1.58 2.42 3.34 4.08 4.49 5.48 6.63 7.92 9.15 9.93 10.97 11.84 14.96 17.04 20.10 23.14
200 0.84 1.33 1.68 2.61 3.67 4.52 5.03 6.14 7.41 8.79 10.12 10.93 12.04 12.89 16.20 18.26 21.34 24.47
500 0.90 1.43 1.80 2.87 4.11 5.14 5.80 7.09 8.52 9.97 11.44 12.31 13.49 14.30 17.89 19.87 22.96 26.19
1000 0.95 1.50 1.89 3.06 4.46 5.64 6.44 7.88 9.43 10.92 12.49 13.40 14.64 15.40 19.20 21.09 24.18 27.48
* These precipitation frequency estimates are based on a partial duration series. ARI is the Average Recurrence Interval.
Please refer to NOAA Atlas 14 Document for more information. NOTE: Formatting forces estimates near zero to appear as zero,
x Upper bound of the 90% confidence interval
Precipitation Frequencv Estimates (inches)
24 48 10 11 20 11 30 45 60
=ARI* 5 10 15 30 60 10 6 []Lg
hr day day day 11 day 11 day day day
min min min min min min hhr hr
0.42 0.68 0.84 1.16 1.45 1.69 1.82 2.22 2.69 3.20 3.81 4.25 4.89 5.56 7.38 9.01 11.36 13.47
0 0.50 0.80 1.01 1.40 1.75 2.05 2.20 2.68 3.25 3.87 4.59 5.11 5.84 6.62 8.72 10.60 13.28 15.71
0 0.59 0.95 1.20 1.70 2.18 2.57 2.76 3.35 4.07 4.87 5.74 6.30 7.11 7.95 10.30 12.28 15.11 17.68
10 0.66 1.05 1.33 1.93 2.51 2.98 3.21 3.89 4.73 5.65 6.63 7.25 8.12 8.99 11.54 13.58 16.52 19.22
25 0.74 1.18 1.49 2.21 2.94 3.54 3.85 4.66 5.65 6.74 7.86 8.54 9.48 10.38 13.20 F152811 8.32 21.19
50 0.80 1.27 1.61 2.43 3.29 3.99 4.39 5.31 6.41 7.60 8.84 9.57 10.57 11.47 14.49 16.59 19.70 22.67
100 0.86 1.37 1.73 2.65 3.65 4.47 4.95 6.00 7.21 8.49 9.84 10.63 11.68 12.58 15.80 1712 7.8103 24.12
200 0.92 1.46 1.84 2.86 4.02 4.97 5.56 6.74 8.07 9.41 10.88 11.71 12.83 13.70 17.14 19.17 22.36 25.53
500 1.00 1.57 1.98 3.15 4.53 5.69 6.45 7.82 9.30 10.71 12.32 13.21 14.39 15.21 18.95 20.89 24.08 27.37
1000 1.06 1.66 2.09 3.38 4.94 6.27 7.19 8.72 10.33 11.73 13.45 14.39 15.64 16.41 20.38 22.22 25.39 28.76
'The umer bound of the confidence interval at 90% confidence level is the value which 5% of the simulated quantile values for a given frequency are greater than.
** These precipitation frequency estimates are based on a partial duration series. AIR[ is the Average Recurrence Interval.
Please refer to NOAA Atlas 14 Document for more information. NOTE: Formatting prevents estimates near zero to appear as zero.
X Lower bound of the 90% confidence interval
Precipitation Freauencv Estimates (inches) 11
ARI1* ? 10 15 30 60 120 3? 6? M12 M24 Mhr ?4 ?7 10 20 30 45 60
(years) mm min 11 min 11 mm 11 mm 11 min hr hr day day day 11 day 11 day 11 day 11 day
0.36 0.57 0.71 0.98 1.22 1.41 1.51 1.87 2.28 2.78 3.29 3.70 4.31 4.95 6.64 8.20 10.39 12.41
0 0.42 0.68 0.85 1.17 1.47 1.71 1.83 2.25 2.75 3.36 3.97 4.45 5.14 5.89 7.85 9.65 12.14 14.47
3.4
0.50 0.79 1.00 1.43 1.83 2.15 2.29 2.81 3 4.234.975.48 6.26 7.079.26 11.1913.83 16.30
10 0.55 0.88 1.11 1.61 2.10 2,48 2.66 3.26 3.97 4.91 5.73 6.30 7.14 7.99 10.36 12.37 15.11 17.71
25 0.61 0.98 1.24 1.84 2.45 2.94 3.17 3.87 4.72 5.83 6.78 7.40 8.32 9.20 11.81 13.89 16.72 19.52
F__7 F__1 F__1 F__1 F7 F7 F7 (-? ?? ? ?1 F___1 F___1 F____? F-1 F__? F___1 F___1
http://dipper.nws.noaa. gov/cgi-binlhdscibuildout.perl?type=pf&units=us&series=pd&stat... 12/13/2010
auencv Estimates (inc

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DA ? 1
SubCat Reach on Link Drainage Diagram for Cottonwood-POND 1 -PRE
Prepared by WSP SELLS, Printed 4/1/2011
HydroCAD® 9.00 s/n 04719 © 2009 HydroCAD Software Solutions LLC

1
1
1
1
1
Cottonwood-POND 1 -PRE
Prepared by WSP SELLS Printed 4/1/2011
HydroCAD® 9.00 s/n 04719 @2009 HydroCAD Software Solutions LLC Page 2
Area Listing (all nodes)
Area CN Description
(acres) (su bcatch m ent-n u m bers)
14.200 60 Woods, Fair, HSG B (1S)
14.200 TOTAL AREA

' Cottonwood-POND 1 -PRE
Prepared by WSP SELLS Printed 4/1/2011
HydroCADS 9.00 s/n 04719 © 2009 HydroCAD Software Solutions LLC Page 3
Soil Listing (all nodes)
' Area Soil Subcatchment
(acres) Goup Numbers
0.000 HSG A
14.200 HSG B 1S
'
0.000 HSG C
0.000 HSG D
' 0.000 Other
14.200 TOTAL AREA

1
1
H

H

Cottonwood-POND 1 -PRE Type 1124-hr 1-year Rainfall=2.98"
Prepared by WSP SELLS Printed 4/1/2011
HydroCAD® 9.00 s/n 04719 02009 HydroCAD Software Solutions LLC Page 4
I

n
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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: DA -1 Runoff Area=14.200 ac 0.00% Impervious Runoff Depth>0.27"
Flow Length=917' Tc=15.1 min CN=60 Runoff=3.35 cfs 0.324 of
Total Runoff Area =14.200 ac Runoff Volume = 0.324 of Average Runoff Depth = 0.27"
100.00% Pervious= 14.200ac 0.00% Impervious= 0.000 ac

' Cottonwood-POND 1 -PRE Type 11 24-hr 1-year Rainfall=2.98"
Prepared by WSP SELLS Printed 4/1/2011
HydroCAD® 9.00 s/n 04719 @2009 HydroCAD Software Solutions LLC Page 5
' Summary for Subcatchment 1S: DA -1
' Runoff = 3.35 cfs @ 12.13 hrs, Volume= 0.324 af, Depth> 0.27"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 1-year Rainfall=2.98"
t
Area (ac) CN Description
14.200 60 Woods, Fair, HSG B
' 14.200 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
' 12.3 100 0.0700 0.14 Sheet Flow, Sheet
Woods: Light underbrush n= 0.400 P2= 3.60"
1.2 445 0.1400 6.02 Shallow Concentrated Flow, Shallow
' Unpaved Kv= 16.1 fps
1.6 372 0.1020 3.97 15.89 Channel Flow, Channel -1
' Area= 4.0 sf Perim= 7.3' r= 0.55'
n= 0.080 Earth, long dense weeds
15.1 917 Total

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2
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0
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1
Subcatchment 1S: DA -1
Hydrograph
Type II 24-hr 1-year
Rainfall=2.98"
Runoff Area 14.2'00 ac
Runoff Volume=0.324' of
Runoff Depth>0.27"
Flow Length=917'
Tc=15.1 min
CN=60
14 15 16 17 18 19 20
5 6 7 8 9 10 11
Runoff
Time (hours)
C
' Cottonwood-POND 1 -PRE Type 11 24-hr 1-year Rainfall=2.98"
Prepared by WSP SELLS Printed 4/1/2011
HydroCAD® 9.00 s/n 04719 02009 HydroCAD Software Solutions LLC Page 6
' Hydrograph for Subcatchment 1S: DA -1

D

F

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Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs)
5.00 0.19 0.00 0.00
5.25 0.20 0.00 0.00
5.50 0.21 0.00 0.00
5.75 0.23 0.00 0.00
6.00 0.24 0.00 0.00
6.25 0.25 0.00 0.00
6.50 0.27 0.00 0.00
675 0.28 0.00 0.00
7.00 0.30 0.00 0.00
7.25 0.31 0.00 0.00
7.50 0.33 0.00 0.00
7.75 0.34 0.00 0.00
8.00 0.36 0.00 0.00
8.25 0.37 0.00 0.00
8.50 0.39 0.00 0.00
8.75 0.42 0.00 0.00
9.00 0.44 0.00 0.00
9.25 0.46 0.00 0.00
9.50 0.49 0.00 0.00
9.75 0.51 0.00 0.00
10.00 0.54 0.00 0.00
10.25 0.57 0.00 0.00
10.50 0.61 0.00 0.00
10.75 0.65 0.00 0.00
11.00 0.70 0.00 0.00
11.25 0.76 0.00 0.00
11.50 0.84 0.00 0.00
11.75 1.15 0.00 0.00
12.00 1.98 0.06 1.31
12.25 2.10 0.08 2.27
12.50 2.19 0.10 1.24
12.75 2.25 0.11 0.85
13.00 2.30 0.12 0.71
13.25 2.34 0.13 0.62
13.50 2.38 0.14 0.56
13.75 2.41 0.15 0.51
14.00 2.44 0.16 0.46
14.25 2.47 0.17 0.42
14.50 2.50 0.17 0.41
14.75 2.52 0.18 0.39
15.00 2.54 0.19 0.38
15.25 2.57 0.19 0.36
15.50 2.59 0.20 0.35
15.75 2.60 0.20 0.33
16.00 2.62 0.21 0.31
16.25 2.64 0.21 0.29
16.50 2.66 0.22 0.29
16.75 2.67 0.22 0.28
17.00 2.69 0.23 0.28
17.25 2.70 0.23 0.27
17.50 2.72 0.24 0.26
17.75 2.73 0.24 0.26
Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs)
18.00 2.74 0.25 0.25
18.25 2.76 0.25 0.24
18.50 2.77 0.25 0.24
18.75 2.78 0.26 0.23
19.00 2.79 0.26 0.22
19.25 2.81 0.27 0.22
19.50 2.82 0.27 0.21
19.75 2.83 0.27 0.20
20.00 2.84 0.28 0.19

Cottonwood-POND 1 -PRE Type 11 24-hr 10-year Rainfall=5.27"
Prepared by WSP SELLS Printed 4/1/2011
HydroCAD® 9.00 s/n 04719 02009 HydroCAD Software Solutions LLC Page 7
' 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: DA -1 Runoff Area=14.200 ac 0.00% Impervious Runoff Depth>1.30"
Flow Length=917' Tc=15.1 min CN=60 Runoff=24.72 cfs 1.541 of
' Total Runoff Area =14.200 ac Runoff Volume =1.541 of Average Runoff Depth =1.30"
100.00% Pervious =14.200 ac 0.00% Impervious = 0.000 ac

1
1

1

Cottonwood-POND 1 -PRE Type// 24-hr 10-year Rainfall=5.27"
Prepared by WSP SELLS Printed 4/1/2011
HydroCAD® 9.00 s/n 04719 @2009 HydroCAD Software Solutions LLC Page 8
Summary for Subcatchment IS: DA -1
' Runoff = 24.72 cfs @ 12.09 hrs, Volume= 1.541 af, Depth> 1.30"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 10-year Rainfall=5.27"
Area (ac) CN Description
14.200 60 Woods, Fair, HSG B
' 14.200 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
' (min) (feet) (ft/ft) (ft/sec) (cfs)
12.3 100 0.0700 0.14 Sheet Flow, Sheet
Woods: Light underbrush n= 0.400 P2= 3.60"
1.2 445 0.1400 6.02 Shallow Concentrated Flow, Shallow
' Unpaved Kv= 16.1 fps
1.6 372 0.1020 3.97 15.89 Channel Flow, Channel -1
Area= 4.0 sf Perim= 7.3' r= 0.55'
n= 0.080 Earth, long dense weeds
15.1 917 Total
Subcatchment 1S: DA -1
Hydrograph
26 24.72 ors
24 Type 11 24-hr 10-year
22 Rainfall=5.27
20 Runoff Area=14
200 ac
18
w 16
3 14
c
LL 12
10
Runoff Volume=1:541 af-
Runoff Depth>1.30„
Flow Length=917'
Tc=15.1 min
_CN=60
5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Time (hours)
® Runoff

' Cottonwood-POND 1 -PRE Type 11 24-hr 10-year Rainfall=5.27'
Prepared by WSP SELLS Printed 4/1/2011
HydroCAD® 9.00 s/n 04719 02009 HydroCAD Software Solutions LLC Page 9
Hydrograph for Subcatchment 1S: DA -1
Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs)
5.00 0.33 0.00 0.00
5.25 0.35 0.00 0.00
5.50 0.38 0.00 0.00
5.75 0.40 0.00 0.00
6.00 0.42 0.00 0.00
6.25 0.45 0.00 0.00
6.50 0.47 0.00 0.00
6.75 0.50 0.00 0.00
7.00 0.52 0.00 0.00
7.25 0.55 0.00 0.00
7.50 0.58 0.00 0.00
7.75 0.60 0.00 0.00
8.00 0.63 0.00 0.00
8.25 0.66 0.00 0.00
8.50 0.70 0.00 0.00
8.75 0.73 0.00 0.00
9.00 0.77 0.00 0.00
9.25 0.82 0.00 0.00
9.50 0.86 0.00 0.00
9.75 0.90 0.00 0.00
10.00 0.95 0.00 0.00
10.25 1.01 0.00 0.00
10.50 1.08 0.00 0.00
10.75 1.15 0.00 0.00
11.00 1.24 0.00 0.00
11.25 1.35 0.00 0.00
11.50 1.49 0.00 0.09
11.75 2.04 0.07 1.38
12.00 3.49 0.53 18.16
12.25 3.72 0.63 12.73
12.50 3.87 0.70 5.39
12.75 3.98 0.75 3.34
13.00 4.07 0.80 2.71
13.25 4.14 0.83 2.30
13.50 4.21 0.87 2.04
13.75 4.27 0.90 1.81
14.00 4.32 0.92 1.63
14.25 4.37 0.95 1.48
14.50 4.41 0.97 1.40
14.75 4.46 1.00 1.34
15.00 4.50 1.02 1.28
15.25 4.54 1.04 1.22
15.50 4.57 1.06 1.15
15.75 4.61 1.08 1.09
16.00 4.64 1.10 1.02
16.25 4.67 1.11 0.96
16.50 4.70 1.13 0.94
16.75 4.72 1.14 0.91
17.00 4.75 1.16 0.89
17.25 4.78 1.17 0.87
17.50 4.80 1.19 0.85
17.75 4.83 1.20 0.82
Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs)
18.00 4.85 1.22 0.80
18.25 4.88 1.23 0.77
18.50 4.90 1.24 0.75
18.75 4.92 1.26 0.73
19.00 4.94 1.27 0.70
19.25 4.96 1.28 0.68
19.50 4.98 1.29 0.65
19.75 5.00 1.30 0.62
20.00 5.02 1.31 0.60

0

H

Cottonwood-POND 1 -PRE Type 11 24-hr 50-year Rainfall=7.09"
Prepared by WSP SELLS Printed 4/1/2011
HydroCAD® 9.00 s/n 04719 02009 HydroCAD Software Solutions LLC Page 10
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: DA -1 Runoff Area=14.200 ac 0.00% Impervious Runoff Depth>2.41"
Flow Length=917' Tc=15.1 min CN=60 Runoff=47.47 cfs 2.857 of
Total Runoff Area =14.200 ac Runoff Volume =2.857 of Average Runoff Depth= 2.41"
100.00% Pervious= 14.200ac 0.00% Impervious= 0.000 ac

LEI

Cottonwood-POND 1 -PRE Type 11 24-hr 50-year Rainfall=7.09"
Prepared by WSP SELLS Printed 4/1/2011
HydroCAD® 9.00 s/n 04719 0 2009 HydroCAD Software Solutions LLC Page 11
Summary for Subcatchment 1 S: DA -1
Runoff = 47.47 cfs @ 12.08 hrs, Volume= 2.857 af, Depth> 2.41"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 50-year Rainfall=7.09"
Area (ac) CN Description
14.200 60 Woods, Fair, HSG B
14.200 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
12.3 100 0.0700 0.14 Sheet Flow, Sheet
Woods: Light underbrush n= 0.400 P2= 3.60"
1.2 445 0.1400 6.02 Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
1.6 372 0.1020 3.97 15.89 Channel Flow, Channel -1
Area= 4.0 sf Perim= 73 r= 0.55'
n= 0.080 Earth. Iona dense weeds
15.1 917 Total
Subcatchment 1S: DA -1
Hydrograph
®Runoff
50- 47.47 cfs
Type 11 24-hr 50-year
45
Rainfall'=7.09"
40
Runoff Area=14.200 ac
35
Runoff Volume=2.857 of
Zw?
30 Runoff Depth>2.41"
3
LL 25
'
Flow Length=917'

20 Tc=15'.1 min
15 CN=60
10
,
5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Time (hours)

Cottonwood-POND 1 -PRE Type 1124-hr 50-year Rainfall=7.09"
Prepared by WSP SELLS Printed 4/1/2011
HydroCADO 9.00 s/n 04719 02009 HydroCAD Software Solutions LLC Page 12
Hydrograph for Subcatchment 1S: DA -1

1
CI

n

Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs)
5.00 0.45 0.00 0.00
5.25 0.48 0.00 0.00
5.50 0.51 0.00 0.00
5.75 0.54 0.00 0.00
6.00 0.57 0.00 0.00
6.25 0.60 0.00 0.00
6.50 0.63 0.00 0.00
6.75 0.67 0.00 0.00
7.00 0.70 0.00 0.00
7.25 0.74 0.00 0.00
7.50 0.77 0.00 0.00
7.75 0.81 0.00 0.00
8.00 0.85 0.00 0.00
8.25 0.89 0.00 0.00
8.50 0.94 0.00 0.00
8.75 0.99 0.00 0.00
9.00 1.04 0.00 0.00
9.25 1.10 0.00 0.00
9.50 1.16 0.00 0.00
9.75 1.22 0.00 0.00
10.00 1.28 0.00 0.00
10.25 1.36 0.00 0.00
10.50 1.45 0.00 0.05
10.75 1.55 0.01 0.19
11.00 1.67 0.02 0.41
11.25 1.82 0.03 0.74
11.50 2.01 0.06 1.35
11.75 2.74 0.25 5.07
12.00 4.70 1.13 37.40
12.25 5.01 1.30 23.22
12.50 5.21 1.43 9.36
12.75 5.35 1.51 5.67
13.00 5.47 1.59 4.56
13.25 5.58 1.65 3.86
13.50 5.66 1.71 3.41
13.75 5.74 1.76 3.02
14.00 5.81 1.80 2.70
14.25 5.88 1.84 2.44
14.50 5.94 1.88 2.31
14.75 6.00 1.92 2.20
15.00 6.05 1.96 2.10
15.25 6.10 1.99 1.99
15.50 6.15 2.02 1.89
15.75 6.20 2.05 1.78
16.00 6.24 2.08 1.67
16.25 6.28 2.11 1.57
16.50 6.32 2.13 1.52
16.75 6.36 2.16 1.48
17.00 6.39 2.18 1.44
17.25 6.43 2.21 1.41
17.50 6.46 2.23 1.37
17.75 6.50 2.25 1.33
Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs)
18.00 6.53 2.28 1.29
18.25 6.56 2.30 1.25
18.50 6.59 2.32 1.21
18.75 6.62 2.34 1.17
19.00 6.65 2.36 1.13
19.25 6.68 2.38 1.08
19.50 6.70 2.39 1.04
19.75 6.73 2.41 1.00
20.00 6.75 2.43 0.96
1
1
1
1
i
1
11
1
1
1
1S
DA- 1
z 1 P
WET POND #1
Subcat Reach on Link Drainage Diagram for Cottonwood-POND 1 -POST-FUTURE
Prepared by WSP SELLS, Printed 4/1/2011
HydroCADO 9.00 s/n 04719 © 2009 HydroCAD Software Solutions LLC
1
1
1
1
1
1
1
Cottonwood-POND 1 -POST-FUTURE
Prepared by WSP SELLS Printed 4/1/2011
HydroCAD@ 9.00 s/n 04719 02009 HydroCAD Software Solutions LLC Page 2
Area Listing (all nodes)
Area CN Description
(acres) (s u bcatch m ent-n u m be rs)
6.900 61 >75% Grass cover, Good, HSG B (1S)
9.400 98 Paved roads w/curbs & sewers, HSG B (1S)
16.300 TOTAL AREA

H

Cottonwood-POND 1 -POST-FUTURE
Prepared by WSP SELLS Printed 4/1/2011
HydroCAD® 9.00 s/n 04719 02009 HydroCAD Software Solutions LLC Page 3
Soil Listing (all nodes)
Area Soil Subcatchment
(acres) Goup Numbers
0.000 HSG A
16.300 HSG B 1S
0.000 HSG C
0.000 HSG D
0.000 Other
16.300 TOTAL AREA

' Cottonwood-POND 1 -POST-FUTURE
Prepared by WSP SELLS Printed 4/1/2011
HydroCADO 9.00 s/n 04719 © 2009 HydroCAD Software Solutions LLC Page 4
' Pipe Listing (all nodes)
' Line# Node In-Invert Out-Invert Length Slope n Diam/Width Height
Number (feet) (feet) (feet) (ft/ft) (inches) (inches)
1 1 P 706.41 705.00 282.0 0.0050 0.013 18.0 0.0
n
' Cottonwood-POND 1 -POST-FUTURE Type 1124-hr 1-year Rainfall=2.98"
Prepared by WSP SELLS Printed 4/1/2011
HydroCADO 9.00 s/n 04719 © 2009 HydroCAD Software Solutions LLC Page 5
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: DA -1 Runoff Area=16.300 ac 57.67% Impervious Runoff Depth>1.25"
Tc=5.0 min CN=82 Runoff=40.05 cfs 1.698 of
' Pond 1P: WET POND #1 Peak Elev=714.13' Storage=94,733 cf Inflow=40.05 cfs 1.698 of
Primary=3.23 cfs 0.780 of Secondary=0.00 cfs 0.000 of Outflow=3.23 cfs 0.780 of
' Total Runoff Area =16.300 ac Runoff Volume =1.698 of Average Runoff Depth =1.25"
42.33% Pervious = 6.900 ac 57.67% Impervious = 9.400 ac

1
' Cottonwood-POND 1 -POST-FUTURE Type// 24-hr 1-year Rainfall=2.98"
Prepared by WSP SELLS Printed 4/1/2011
HydroCAD® 9.00 s/n 04719 02009 HydroCAD Software Solutions LLC Page 6
Summary for Subcatchment IS: DA -1
' [49] Hint: Tc<2dt may require smaller dt
Runoff = 40.05 cfs @ 11.96 hrs, Volume= 1.698 af, Depth> 1.25"
' Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 1-year Rainfall=2.98"
' Area (ac) CN Description
6.900 61 >75% Grass cover, Good, HSG B
9.400 98 Paved roads w/curbs & sewers, HSG B
' 16.300 82 Weighted Average
6.900 42.33% Pervious Area
9.400 57.67% Impervious Area
' Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
' 5.0 Direct Entry,
Subcatchment 1S: DA - 1
' Hydrograph
44 _ . .. _ ®Runoff

' 42
40 40.05 crs

Type II 24-hr 1-year
38
36 Rainfall=2.98'"-
34 , . __.
32 - - - - Runoff A
ea=16
300 ac
30 r
.
28 - - Runoff Volume=1
698 of
y 26 .
v 24 Runoff f Depth>1.25"
' 3 22
LL 20
Tc=5,0-min--
16 ,
CN.=82
r 14: " ,
12 -
10-

'
8
6-
4
,
2
0

5 6 7
,, ,
8 9 10 11 12 13 14 15 18 17 18 19 20
Time (hours)

Cottonwood-POND 1 -POST-FUTURE Type 1124-hr 1-year Rainfall=2.98"
Prepared by WSP SELLS Printed 4/1/2011
HydroCAD® 9.00 s/n 04719 @2009 HydroCAD Software Solutions LLC Page 7
Hydrograph for Subcatchment 1S: DA -1
Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs)
5.00 0.19 0.00 0.00
5.25 0.20 0.00 0.00
5.50 0.21 0.00 0.00
5.75 0.23 0.00 0.00
6.00 0.24 0.00 0.00
6.25 0.25 0.00 0.00
6.50 0.27 0.00 0.00
6.75 0.28 0.00 0.00
7.00 0.30 0.00 0.00
7.25 0.31 0.00 0.00
7.50 0.33 0.00 0.00
7.75 0.34 0.00 0.00
8.00 0.36 0.00 0.00
8.25 0.37 0.00 0.00
8.50 0.39 0.00 0.00
8.75 0.42 0.00 0.00
9.00 0.44 0.00 0.00
9.25 0.46 0.00 0.02
9.50 0.49 0.00 0.05
9.75 0.51 0.00 0.10
10.00 0.54 0.00 0.15
10.25 0.57 0.01 0.22
10.50 0.61 0.01 0.32
10.75 0.65 0.02 0.46
11.00 0.70 0.03 0.64
11.25 0.76 0.04 0.99
11.50 0.84 0.06 1.50
11.75 1.15 0.18 9.76
12.00 1.98 0.63 35.41
12.25 2.10 0.72 5.32
12.50 2.19 0.78 3.52
12.75 2.25 0.82 2.66
13.00 2.30 0.85 2.25
13.25 2.34 0.88 1.96
13.50 2.38 0.91 1.73
13.75 2.41 0.94 1.54
14.00 2.44 0.96 1.37
14.25 2.47 0.98 1.28
14.50 2.50 1.00 1.22
14.75 2.52 1.01 1.16
15.00 2.54 1.03 1.10
15.25 2.57 1.05 1.05
15.50 2.59 1.06 0.98
15.75 2.60 1.08 0.92
16.00 2.62 1.09 0.86
16.25 2.64 1.10 0.83
16.50 2.66 1.11 0.81
16.75 2.67 1.13 0.79
17.00 2.69 1.14 0.77
17.25 2.70 1.15 0.74
17.50 2.72 1.16 0.72
17.75 2.73 1.17 0.70
Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs)
18.00 2.74 1.18 0.68
18.25 2.76 1.19 0.66
18.50 2.77 1.20 0.63
18.75 2.78 1.21 0.61
19.00 2.79 1.22 0.59
19.25 2.81 1.23 0.57
19.50 2.82 1.24 0.54
19.75 2.83 1.24 0.52
20.00 2.84 1.25 0.50

' Cottonwood-POND 1 -POST-FUTURE Type// 24-hr 1-year Rainfall=2.98"
Prepared by WSP SELLS Printed 4/1/2011
HydroCAD® 9.00 s/n 04719 02009 HydroCAD Software Solutions LLC Page 8
Summary for Pond 1 P: WET POND #1
' Inflow Area = 16.300 ac, 57.67% Impervious, Inflow Depth > 1.25" for 1-year event
Inflow 40.05 cfs @ 11.96 hrs, Volume= 1.698 of
Outflow = 3.23 cfs @ 12.55 hrs, Volume= 0.780 af, Atten= 92%, Lag= 35.4 min
' Primary = 3.23 cfs @ 12.55 hrs, Volume= 0.780 of
Secondary = 0.00 cfs @ 5.00 hrs, Volume= 0.000 of
Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
' Starting Elev= 712.00' Surf.Area= 16,289 sf Storage= 52,357 cf
Peak Elev= 714.13' @ 12.55 hrs Surf.Area= 23,161 sf Storage= 94,733 cf (42,376 cf above start)
' Plug-Flow detention time= (not calculated: initial storage excedes outflow)
Center-of-Mass det. time= 104.1 min ( 895.9 - 791.8 )
Volume Invert Avail.Storage Storage Description
' #1 707.00' 184,894 cf Custom Stage Data (Prismatic) Listed below
Elevation Surf.Area Inc.Store Cum.Store
' (feet) (sq-ft) (cubic-feet) (cubic-feet)
707.00 5,959 0 0
708.00 7,395 6,677 6,677
' 710.00 10,998 18,393 25,070
712.00 16,289 27,287 52,357
714.00 22,907 39,196 91,553
' 716.00 26,876 49,783 141,336
717.00 28,945 27,911 169,247
717.50 33,644 15,647 184,894
' Device Routing Invert Outlet Devices
#1 Primary 706.41' 18.0" Round Culvert
L= 282.0' RCP, groove end projecting, Ke= 0.200
' Outlet Invert= 705.00' S= 0.00507' Cc= 0.900
n= 0.013 Concrete pipe, straight & clean
#2 Secondary 716.25' 10.0' long x 24.0' breadth Broad-Crested Rectangular Weir
' Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Coef. (English) 2.68 2.70 2.70 2.64 2.63 2.64 2.64 2.63
#3 Device 1 712.00' 2.0" Vert. Orifice/Grate C= 0.600
#4 Device 1 714.00' 60.0" x 60.0" Horiz. Orifice/Grate C= 0.600
' Limited to weir flow at low heads
Primary OutFlow Max=3.14 cfs @ 12.55 hrs HW=714.13' (Free Discharge)
' L1=Culvert (Passes 3.14 cfs of 15.53 cfs potential flow)
3=Orifice/Grate (Orifice Controls 0.15 cfs @ 6.88 fps)
=Orifice/Grate (Weir Controls 2.98 cfs @ 1.17 fps)
Secondary OutFlow Max=0.00 cfs @ 5.00 hrs HW=712.00' (Free Discharge)
2=Broad-Crested Rectangular Weir (Controls 0.00 cfs)
Cottonwood-POND 1 -POST-FUTURE Type 1124-hr 1-year Rainfall=2.98"
Prepared by WSP SELLS Printed 4/1/2011
HydroCADO 9.00 s/n 04719 © 2009 HydroCAD Software Solutions LLC Page 9
Pond 1P: WET POND #1
Hydrograph
IM=
40.05 cfs :, - ow
Inflow Area=16
300 ac L
Prima
d
44
.
n
ary
42 Peak Elev-714.13'

40- ..
38-
36-
-
-
- --- Storage=94,733 cf
34
32 _._. .. ._1...._.. - _

30 ---- -----------
- -- - - -
28 _-
24
22-, :
0 20
LL

16 -
<
12 .
10 "
$_
323 cfs .? --

4 3.23 cfs

5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Time (hours)

' Cottonwood-POND 1 -POST-FUTURE Type 11 24-hr 1-year Rainfall=2.98"
Prepared by WSP SELLS Printed 4/1/2011
HydroCAD® 9.00 s/n 04719 (92009 HydroCAD Software Solutions LLC Page 10
' Hydrograph for Pond 1 P: WET POND #1
t Time
(hours) Inflow
(cfs) Storage
(cubic-feet) Elevation
(feet) Outflow
(cfs) Primary
(cfs) Secondary
(cfs)
5.00 0.00 52,357 712.00 0.00 0.00 0.00
5.50 0.00 52,357 712.00 0.00 0.00 0.00
6.00 0.00 52,357 712.00 0.00 0.00 0.00
6.50 0.00 52,357 712.00 0.00 0.00 0.00
7.00 0.00 52,357 712.00 0.00 0.00 0.00
7.50 0.00 52,357 712.00 0.00 0.00 0.00
' 8.00 0.00 52,357 712.00 0.00 0.00 0.00
8.50 0.00 52,357 712.00 0.00 0.00 0.00
9.00 0.00 52,357 712.00 0.00 0.00 0.00
' 9.50
10.00 0.05
0.15 52,398
52,573 712.00
712.01 0.00
0.00 0.00
0.00 0.00
0.00
10.50 0.32 52,976 712.03 0.00 0.00 0.00
11.00 0.64 53,803 712.07 0.01 0.01 0.00
11.50 1.50 55,597 712.17 0.03 0.03 0.00
' 12.00 35.41 82,121 713.52 0.13 0.13 0.00
12.50 3.52 94,709 714.13 3.20 3.20 0.00
13.00 2.25 94,212 714.11 2.63 2.63 0.00
' 13.50 1.73 93,647 714.08 1.98 1.98 0.00
14.00 1.37 93,271 714.07 1.55 1.55 0.00
14.50 1.22 93,053 714.06 1.30 1.30 0.00
' 15.00
15.50 1.10
0.98 92,937
92,832 714.06
714.05 1.16
1.04 1.16
1.04 0.00
0.00
16.00 0.86 92,726 714.05 0.92 0.92 0.00
16.50 0.81 92,651 714.04 0.84 0.84 0.00
17.00 0.77 92,609 714.04 0.79 0.79 0.00
' 17.50 0.72 92,571 714.04 0.74 0.74 0.00
18.00 0.68 92,533 714.04 0.70 0.70 0.00
18.50 0.63 92,495 714.04 0.66 0.66 0.00
' 19.00 0.59 92,456 714.04 0.61 0.61 0.00
19.50 0.54 92,416 714.03 0.57 0.57 0.00
20.00 0.50 92,353 714.03 0.54 0.54 0.00

Cottonwood-POND 1 -POST-FUTURE Type// 24-hr 10-year Rainfall=5.27'
Prepared by WSP SELLS Printed 4/1/2011
HydroCADS 9.00 s/n 04719 @2009 HydroCAD Software Solutions LLC Page 11
f 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: DA -1 Runoff Area=16.300 ac 57.67% Impervious Runoff Depth>3.09"
Tc=5.0 min CN=82 Runoff=95.38 cfs 4.199 of
Pond 1P: WET POND #1 Peak Elev=716.04' Storage=142,569 cf Inflow=95.38 cfs 4.199 of
Primary=17.38 cfs 3.269 of Secondary=0.00 cfs 0.000 of Outflow= 17.38 cfs 3.269 of
Total Runoff Area =16.300 ac Runoff Volume = 4.199 of Average Runoff Depth = 3.09"
42.33 /o Pervious = 6.900 ac 57.67 /o Impervious = 9.400 ac

' Cottonwood-POND 1 -POST-FUTURE Type// 24-hr 10-year Rainfall=5.27'
Prepared by WSP SELLS Printed 4/1/2011
HydroCAD® 9.00 s/n 04719 @2009 HydroCAD Software Solutions LLC Page 12
Summary for Subcatchment 1S: DA -1
' [49] Hint: Tc<2dt may require smaller dt
Runoff = 95.38 cfs @ 11.95 hrs, Volume= 4.199 af, Depth> 3.09"
' Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 10-year Rainfall=5.27"
' Area (ac) CN Description
6.900 61 >75% Grass cover, Good, HSG B
9.400 98 Paved roads w/curbs & sewers, HSG B
' 16.300 82 Weighted Average
6.900 42.33% Pervious Area
9.400 57.67% Impervious Area

Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry,
Subcatchment 1S: DA -1
1
1
1
1
Hydrograph
10s
100 ? _. - ? Runoff
95.38 cfs
95- yfJ ` p e 11 4-r 1
90 0-year
85 Rainfall=5.27"
80-
7511, - - - Runoff Area=16.300 ac-
?d'f///iF//Ai1N/?" %ff%?IJ. . .
T----r I i??-t-r..iT-ice-i i-ri i iT? ri--?i n i-'i-i nZ-n Ti-+T?
5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
Time (hours)

' Cottonwood-POND 1 -POST-FUTURE Type 11 24-hr 10-year Rainfall=5.27'
Prepared by WSP SELLS Printed 4/1/2011
HydroCAD® 9.00 s/n 04719 @2009 HydroCAD Software Solutions LLC Page 13
Hydrograph for Subcatchment 1S: DA -1
Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs)
5.00 0.33 0.00 0.00
5.25 0.35 0.00 0.00
5.50 0.38 0.00 0.00
5.75 0.40 0.00 0.00
6.00 0.42 0.00 0.00
6.25 0.45 0.00 0.00
6.50 0.47 0.00 0.03
6.75 0.50 0.00 0.07
7.00 0.52 0.00 0.11
7.25 0.55 0.01 0.15
7.50 0.58 0.01 0.19
7.75 0.60 0.01 0.24
8.00 0.63 0.02 0.28
8.25 0.66 0.02 0.35
8.50 0.70 0.03 0.44
8.75 0.73 0.03 0.54
9.00 0.77 0.04 0.65
9.25 0.82 0.06 0.73
9.50 0.86 0.07 0.80
9.75 0.90 0.08 0.94
10.00 0.95 0.10 1.13
10.25 1.01 0.12 1.38
10.50 1.08 0.14 1.69
10.75 1.15 0.17 2.14
11.00 1.24 0.21 2.70
11.25 1.35 0.27 3.75
11.50 1.49 0.34 5.17
11.75 2.04 0.67 28.47
12.00 3.49 1.78 82.01
12.25 3.72 1.97 11.72
12.50 3.87 2.10 7.66
12.75 3.98 2.19 5.76
13.00 4.07 2.26 4.82
13.25 4.14 2.33 4.19
13.50 4.21 2.38 3.68
13.75 4.27 2.43 3.27
14.00 4.32 2.48 2.90
14.25 4.37 2.52 2.70
14.50 4.41 2.56 2.57
14.75 4.46 2.60 2.45
15.00 4.50 2.63 2.32
15.25 4.54 2.67 2.19
15.50 4.57 2.70 2.06
15.75 4.61 2.73 1.93
16.00 4.64 2.76 1.80
16.25 4.67 2.78 1.73
16.50 4.70 2.81 1.68
16.75 4.72 2.83 1.63
17.00 4.75 2.86 1.59
17.25 4.78 2.88 1.54
17.50 4.80 2.90 1.50
17.75 4.83 2.93 1.45
Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs)
18.00 4.85 2.95 1.40
18.25 4.88 2.97 1.35
18.50 4.90 2.99 1.31
18.75 4.92 3.01 1.26
19.00 4.94 3.03 1.21
19.25 4.96 3.05 1.17
19.50 4.98 3.06 1.12
19.75 5.00 3.08 1.07
20.00 5.02 3.09 1.02
l
' Cottonwood-POND 1 -POST-FUTURE Type// 24-hr 10-year Rainfal1=5.27"
Prepared by WSP SELLS Printed 4/1/2011
HydroCAD0 9.00 s/n 04719 @2009 HydroCAD Software Solutions LLC Page 14
' Summary for Pond 1 P: WET POND #1
' Inflow Area = 16.300 ac, 57.67% Impervious, Inflow Depth > 3.09" for 10-year event
Inflow 95.38 cfs @ 11.95 hrs, Volume= 4.199 of
Outflow = 17.38 cfs @ 12.13 hrs, Volume= 3.269 af, Atten= 82%, Lag= 10.8 min
' Primary = 17.38 cfs @ 12.13 hrs, Volume= 3.269 of
Secondary = 0.00 cfs @ 5.00 hrs, Volume= 0.000 of
Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
' Starting Elev= 712.00' Surf.Area= 16,289 sf Storage= 52,357 cf
Peak Elev= 716.04'@ 12.13 hrs Surf.Area= 26,967 sf Storage= 142,569 cf (90,212 cf above start)
' Plug-Flow detention time= 183.6 min calculated for 2.067 of (49% of inflow)
Center-of-Mass det. time= 52.5 min ( 824.6 - 772.1 )
Volume Invert Avail.Storage Storage Description
' #1 707.00' 184,894 cf Custom Stage Data (Prismatic) Listed below
Elevation Surf.Area Inc.Store Cum.Store
' (feet) (sq-ft) (cubic-feet) (cubic-feet)
707.00 5,959 0 0
708.00 7,395 6,677 6,677
' 710.00 10,998 18,393 25,070
712.00 16,289 27,287 52,357
714.00 22,907 39,196 91,553
' 716.00 26,876 49,783 141,336
717.00 28,945 27,911 169,247
717.50 33,644 15,647 184,894
' Device Routing Invert Outlet Devices
#1 Primary 706.41' 18.0" Round Culvert
L= 282.0' RCP, groove end projecting, Ke= 0.200
' Outlet Invert= 705.00' S= 0.00507' Cc= 0.900
n= 0.013 Concrete pipe, straight & clean
#2 Secondary 716.25' 10.0' long x 24.0' breadth Broad-Crested Rectangular Weir
' Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Coef. (English) 2.68 2.70 2.70 2.64 2.63 2.64 2.64 2.63
#3 Device 1 712.00' 2.0" Vert. Orifice/Grate C= 0.600
#4 Device 1 714.00' 60.0" x 60.0" Horiz. Orifice/Grate C= 0.600
' Limited to weir flow at low heads
Primary OutFlow Max=17.37 cfs @ 12.13 hrs HW=716.04' (Free Discharge)
' L1=Culvert (Barrel Controls 17.37 cfs @ 9.83 fps)
t?=Orifice/G =Orifice/Grate (Passes < 0.21 cfs potential flow)
r ate (Passes < 171.98 cfs potential flow)
' Secondary OutFlow Max=0.00 cfs @ 5.00 hrs HW=712.00' (Free Discharge)
2=Broad-Crested Rectangular Weir (Controls 0.00 cfs)
Cottonwood-POND 1 -POST-FUTURE Type 11 24-hr 10-year Rainfall=5.27`
Prepared by WSP SELLS Printed 4/1/2011
HydroCADO 9.00 s/n 04719 © 2009 HydroCAD Software Solutions LLC Page 15
' Pond 1P: WET POND #1
Hydrograph
... -...... ...._ ..... _4. .... NInflow
95.3Bcfs ? Outflow
Inflow Area= 16
300 ac 0 Primary
105 . ? Secondary
' 100 ." . "" . C 4?
Peak Elev 716.0
95- _.
go-
Storage=142
569 `cf
6
5
,
80
75 ..
70-
65-
60, "
?
.
55 ,
3
0 50
-
u 45
40..

35 _
30
.38 cfs
17.3

25- 17.38 c
20-

10
_
5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Time (hours)

Cottonwood-POND 1 -POST-FUTURE Type 11 24-hr 10-year Rainfall=5.27"
Prepared by WSP SELLS Printed 4/1/2011
HydroCADO 9.00 s/n 04719 02009 HydroCAD Software Solutions LLC Page 16
i Hydrograph for Pond 1 P: WET POND #1
Time
(hours) Inflow
(cfs) Storage
(cubic-feet) Elevation
(feet) Outflow
(cfs) Primary
(cfs) Secondary
(cfs)
5.00 0.00 52,357 712.00 0.00 0.00 0.00
5.50 0.00 52,357 712.00 0.00 0.00 0.00
6.00 0.00 52,357 712.00 0.00 0.00 0.00
6.50 0.03 52,372 712.00 0.00 0.00 0.00
7.00 0.11 52,502 712.01 0.00 0.00 0.00
7.50 0.19 52,774 712.02 0.00 0.00 0.00
8.00 0.28 53,198 712.04 0.00 0.00 0.00
8.50 0.44 53,820 712.07 0.01 0.01 0.00
9.00 0.65 54,761 712.12 0.02 0.02 0.00
9.50
10.00 0.80
1.13 56,029
57,659 712.19
712.27 0.03
0.05 0.03
0.05 0.00
0.00
10.50 1.69 60,073 712.39 0.06 0.06 0.00
11.00 2.70 63,839 712.59 0.07 0.07 0.00
11.50 5.17 70,525 712.93 0.10 0.10 0.00
12.00 82.01 131,261 715.60 16.96 16.96 0.00
12.50 7.66 134,221 715.71 17.07 17.07 0.00
13.00 4.82 114,679 714.93 16.33 16.33 0.00
13.50 3.68 97,058 714.22 7.06 7.06 0.00
14.00 2.90 94,847 714.13 3.36 3.36 0.00
14.50 2.57 94,318 714.11 2.75 2.75 0.00
15.00
15.50 2.32
2.06 94,056
93,827 714.10
714.09 2.45
2.19 2.45
2.19 0.00
0.00
16.00 1.80 93,599 714.08 1.92 1.92 0.00
16.50 1.68 93,438 714.08 1.74 1.74 0.00
17.00 1.59 93,347 714.07 1.63 1.63 0.00
17.50 1.50 93,265 714.07 1.54 1.54 0.00
18.00 1.40 93,183 714.07 1.45 1.45 0.00
18.50 1.31 93,102 714.06 1.35 1.35 0.00
19.00 1.21 93,020 714.06 1.26 1.26 0.00
19.50 1.12 92,937 714.06 1.16 1.16 0.00
20.00 1.02 92,854 714.05 1.07 1.07 0.00

11

1
1

Cottonwood-POND 1 -POST-FUTURE Type 11 24-hr 50-year Rainfall=7.09"
Prepared by WSP SELLS Printed 4/1/2011
HydroCAD® 9.00 s/n 04719 @2009 HydroCAD Software Solutions LLC Page 17
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: DA -1 Runoff Area=16.300 ac 57.67% Impervious Runoff Depth>4.68"
Tc=5.0 min CN=82 Runoff=140.64 cfs 6.354 of
Pond 1P: WET POND #1 Peak Elev=717.38' Storage=181,268 cf Inflow=140.64 cfs 6.354 of
Primary=18.56 cfs 4.614 of Secondary=31.75 cfs 0.802 of Outflow=50.30 cfs 5.415 of
Total Runoff Area =16.300 ac Runoff Volume = 6.354 of Average Runoff Depth = 4.68"
42.33% Pervious = 6.900 ac 57.67% Impervious = 9.400 ac

' Cottonwood-POND 1 -POST-FUTURE Type 11 24-hr 50-year Rainfall=7.09"
Prepared by WSP SELLS Printed 4/1/2011
HydroCADO 9.00 s/n 04719 © 2009 HydroCAD Software Solutions LLC Page 18
Summary for Subcatchment 1S: DA -1
' [49] Hint: Tc<2dt may require smaller dt
Runoff = 140.64 cfs @ 11.95 hrs, Volume= 6.354 af, Depth> 4.68"
' Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 50-year Rainfall=7.09"
' Area (ac) CN Description
6.900 61 >75% Grass cover, Good, HSG B
9.400 98 Paved roads w/curbs & sewers, HSG B
' 16.300 82 Weighted Average
6.900 42.33% Pervious Area
9.400 57.67% Impervious Area

1
L7,
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry,
Subcatchment 1S: DA -1

Hydrograph
150-
.
140 64 ds
140
Type 11 24-hr 50-year
130-
Rainfall=7.09
120
110 Runoff
Area 16.300 ac
100-
Runoff 'Volume=6.354 af-
90-
80-'' Runoff Depth>4.68'?
70 Tc=5.0 min
60 CN=82-
50
40
30
20
10-
0
5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Time (hours)

11

Cottonwood-POND 1 -POST-FUTURE Type 11 24-hr 50-year Rainfall= 7.09"
Prepared by WSP SELLS Printed 4/1/2011
HydroCAD@ 9.00 s/n 04719 @2009 H droCAD Software Solutions LLC Page 19
Hydrograph for Subcatchment IS: DA -1
Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs)
5.00 0.45 0.00 0.00
5.25 0.48 0.00 0.05
5.50 0.51 0.00 0.10
5.75 0.54 0.00 0.15
6.00 0.57 0.01 0.21
6.25 0.60 0.01 0.27
6.50 0.63 0.02 0.33
6.75 0.67 0.02 0.39
7.00 0.70 0.03 0.45
7.25 0.74 0.04 0.52
7.50 0.77 0.04 0.58
7.75 0.81 0.05 0.65
8.00 0.85 0.07 0.72
8.25 0.89 0.08 0.85
8.50 0.94 0.09 1.00
8.75 0.99 0.11 1.18
9.00 1.04 0.13 1.37
9.25 1.10 0.15 1.50
9.50 1.16 0.18 1.58
9.75 1.22 0.20 1.81
10.00 1.28 0.23 2.13
10.25 1.36 0.27 2.55
10.50 1.45 0.32 3.05
10.75 1.55 0.37 3.77
11.00 1.67 0.44 4.65
11.25 1.82 0.53 6.31
11.50 2.01 0.65 8.50
11.75 2.74 1.18 44.75
12.00 4.70 2.81 119.75
12.25 5.01 3.08 16.83
12.50 5.21 3.27 10.96
12.75 5.35 3.40 8.22
13.00 5.47 3.51 6.87
13.25 5.58 3.60 5.95
13.50 5.66 3.68 5.22
13.75 5.74 3.75 4.64
14.00 5.81 3.82 4.11
14.25 5.88 3.87 3.82
14.50 5.94 3.93 3.64
14.75 6.00 3.98 3.46
15.00 6.05 4.03 3.28
15.25 6.10 4.08 3.09
15.50 6.15 4.13 2.91
15.75 6.20 4.17 2.72
16.00 6.24 4.21 2.54
16.25 6.28 4.24 2.43
16.50 6.32 4.28 2.37
16.75 6.36 4.32 2.30
17.00 6.39 4.35 2.24
17.25 6.43 4.38 2.17
17.50 6.46 4.42 2.10
17.75 6.50 4.45 2.04
Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs)
18.00 6.53 4.48 1.97
18.25 6.56 4.51 1.90
18.50 6.59 4.53 1.84
18.75 6.62 4.56 1.77
19.00 6.65 4.59 1.70
19.25 6.68 4.61 1.64
19.50 6.70 4.64 1.57
19.75 6.73 4.66 1.50
20.00 6.75 4.68 1.43
11
' Cottonwood-POND 1 -POST-FUTURE Type 1124-hr 50-year Rainfall=7.09"
Prepared by WSP SELLS Printed 4/1/2011
HydroCAD® 9.00 s/n 04719 02009 HydroCAD Software Solutions LLC Page 20
Summary for Pond 1 P: WET POND #1
Inflow Area = 16.300 ac, 57.67% Impervious, Inflow Depth > 4.68" for 50-year event
Inflow 140.64 cfs @ 11.95 hrs, Volume= 6.354 of
Outflow = 50.30 cfs @ 12.07 hrs, Volume= 5.415 af, Atten= 64%, Lag= 7.2 min
Primary = 18.56 cfs @ 12.07 hrs, Volume= 4.614 of
Secondary = 31.75 cfs @ 12.07 hrs, Volume= 0.802 of
Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
' Starting Elev= 712.00' Surf.Area= 16,289 sf Storage= 52,357 cf
Peak Elev= 717.38'@ 12.07 hrs Surf.Area= 32,555 sf Storage= 181,268 cf (128,911 cf above start)
Plug-Flow detention time= 148.2 min calculated for 4.199 of (66% of inflow)
Center-of-Mass det. time= 52.3 min ( 814.8 - 762.5)
Volume Invert Avail.Storage Storage Description
#1 707.00' 184,894 cf Custom Stage Data (Prismatic) Listed below
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic-feet) (cubic-feet)
707.00 5,959 0 0
708.00 7,395 6,677 6,677
' 710.00 10,998 18,393 25,070
712.00 16,289 27,287 52,357
714.00 22,907 39,196 91,553
' 716.00 26,876 49,783 141,336
717.00 28,945 27,911 169,247
717.50 33,644 15,647 184,894
Device Routing Invert Outlet Devices
#1 Primary 706.41' 18.0" Round Culvert
L= 282.0' RCP, groove end projecting, Ke= 0.200
' Outlet Invert= 705.00' S= 0.00507' Cc= 0.900
n= 0.013 Concrete pipe, straight & clean
#2 Secondary 716.25' 10.0' long x 24.0' breadth Broad-Crested Rectangular Weir
' Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Coef. (English) 2.68 2.70 2.70 2.64 2.63 2.64 2.64 2.63
#3 Device 1 712.00' 2.0" Vert. Orifice/Grate C= 0.600
#4 Device 1 714.00' 60.0" x 60.0" Horiz. Orifice/Grate C= 0.600
' Limited to weir flow at low heads
Primary OutFlow Max=18.53 cfs @ 12.07 hrs HW=717.35' (Free Discharge)
L1=Culvert (Barrel Controls 18.53 cfs @ 10.48 fps)
3=Orifice/Grate (Passes < 0.24 cfs potential flow)
=Orifice/Grate (Passes < 220.27 cfs potential flow)
' Secondary OutFlow Max=30.34 cfs @ 12.07 hrs HW=717.35' (Free Discharge)
2=Broad-Crested Rectangular Weir (Weir Controls 30.34 cfs @ 2.76 fps)
Cottonwood-POND 1 -POST-FUTURE Type 11 24-hr 50-year Rainfall=7.09"
Prepared by WSP SELLS Printed 4/1/2011
HydroCADO 9.00 s/n 04719 0 2009 HydroCAD Software Solutions LLC Page 21
Pond 1 P: WET POND #1
Hydrograph
¦ Inflow
140.64 cfs - ? outflow
Inflow Area=16.300 ac ®Primary
? Secondary
150 _ ;.
Peak Elev=717.38'
140- ? _.._ ,.._ _ L..
130 Storage=181,268 cf
,20
110-
__ ...__..;-. ;_ ... ;.-.... _ _....
100-M,
w go-
80-:: ----
C 70 50.30 cfs .. ..... ... .. .......
60
50
40 '
31.75 cfs I -
30 cfs
20-
101 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Time (hours)

t Cottonwood-POND 1 -POST-FUTURE Type// 24-hr 50-year Rainfall=7.09"
Prepared by WSP SELLS Printed 4/1/2011
HydroCAD@ 9.00 s/n 04719 © 2009 HydroCAD Software Solutions LLC Page 22
' Hydrograph for Pond 1 P: WET POND #1
Time Inflow Storage Elevation Outflow Primary Secondary
' (hours) (cfs) (cubic-feet) (feet) (cfs) (cfs) (cfs)
5.00 0.00 52,357 712.00 0.00 0.00 0.00
5.50 0.10 52,443 712.00 0.00 0.00 0.00
6.00 0.21 52,715 712.02 0.00 0.00 0.00
' 6.50 0.33 53,189 712.04 0.00 0.00 0.00
7.00 0.45 53,875 712.08 0.01 0.01 0.00
7.50 0.58 54,778 712.12 0.02 0.02 0.00
' 8.00 0.72 55,907 712.18 0.03 0.03 0.00
8.50 1.00 57,371 712.26 0.04 0.04 0.00
9.00 1.37 59,412 712.36 0.06 0.06 0.00
9.50 1.58 61,989 712.49 0.07 0.07 0.00
' 10.00 2.13 65,140 712.65 0.08 0.08 0.00
10.50 3.05 69,594 712.88 0.09 0.09 0.00
11.00 4.65 76,240 713.22 0.11 0.11 0.00
11.50 8.50 87,507 713.79 0.14 0.14 0.00
' 12.00 119.75 171,489 717.07 37.96 18.29 19.67
12.50 10.96 156,517 716.54 22.13 17.83 4.31
13.00 6.87 138,609 715.89 17.24 17.24 0.00
' 13.50 5.22 118,987 715.10 16.50 16.50 0.00
14.00 4.11 99,132 714.30 11.27 11.27 0.00
14.50 3.64 95,305 714.15 4.04 4.04 0.00
15.00 3.28 94,924 714.14 3.45 3.45 0.00
' 15.50 2.91 94,610 714.12 3.08 3.08 0.00
16.00 2.54 94,288 714.11 2.72 2.72 0.00
16.50 2.37 94,058 714.10 2.45 2.45 0.00
17.00 2.24 93,928 714.10 2.30 2.30 0.00
' 17.50 2.10 93,811 714.09 2.17 2.17 0.00
18.00 1.97 93,696 714.09 2.04 2.04 0.00
18.50 1.84 93,580 714.08 1.90 1.90 0.00
19.00 1.70 93,463 714.08 1.77 1.77 0.00
19.50 1.57 93,347 714.07 1.63 1.63 0.00
20.00 1.43 93,230 714.07 1.50 1.50 0.00

1

I I I

1

J

P

is )
DA? 1
Subca# Reach on Link Drainage Diagram for Cottonwood-POND 1 -PRE
Prepared by WSP SELLS, Printed 4/1/2011
HydroCAD® 9.00 s/n 04719 © 2009 HydroCAD Software Solutions LLC
1
1
1
1

11

Cottonwood-POND 1 -PRE
Prepared by WSP SELLS Printed 4/1/2011
HydroCAD@ 9 00 s/n 04719 @2009 HydroCAD Software Solutions LLC Page 2
Area Listing (all nodes)
Area CN Description
(acres) (subcatchment-numbers)
14.200 60 Woods, Fair, HSG B (1 S)
14.200 TOTAL AREA
1
1

1
1

1

Cottonwood-POND 1 -PRE
Prepared by WSP SELLS Printed 4/1/2011
HydroCAn0 a nn can 04719 02009 HydroCAD Software Solutions LLC Page 3
Soil Listing (all nodes)
Area Soil Subcatchment
(acres) Goup Numbers
0.000 HSG A
14.200 HSG B 1S
0.000 HSG C
0.000 HSG D
0.000 Other
14.200 TOTAL AREA

' Cottonwood-POND 1 -PRE Type 11 24-hr 1-year Rainfall=2.98"
Prepared by WSP SELLS Printed 4/1/2011
HydroCAD® 9.00 s/n 04719 @2009 HydroCAD Software Solutions LLC Page 4
' 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. DA -1 Runoff Area=14.200 ac 0.00% Impervious Runoff Depth>0.27"
Flow Length=917' Tc=15.1 min CN=60 Runoff=3.35 cfs 0.324 of
' Total Runoff Area =14.200 ac Runoff Volume = 0.324 of Average Runoff Depth = 0.27"
100.00% Pervious= 14.200ac 0.00% Impervious = 0.000 ac

D

D

' Cottonwood-POND 1 -PRE Type 11 24-hr 1-year Rainfall=2.98"
Prepared by WSP SELLS Printed 4/1/2011
HydroCADO 9.00 s/n 04719 © 2009 HydroCAD Software Solutions LLC Page 5
' Summa for Subcatchment 1S: DA -1
' Runoff = 3.35 cfs @ 12.13 hrs, Volume= 0.324 af, Depth> 0.27"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 1-year Rainfall=2.98"
Area (ac) CN Description
14.200 60 Woods, Fair, HSG B
' 14.200 100.00% Pervious Area
Tc
(min) Length
(feet) Slope
(ft/ft) Velocity
(ft/sec) Capacity Description
(cfs)
12.3 100 0.0700 0.14 Sheet Flow, Sheet
Woods: Light underbrush n= 0.400 P2= 3.60"
1.2 445 0.1400 6.02 Shallow Concentrated Flow, Shallow
' Unpaved Kv= 16.1 fps
1.6 372 0.1020 3.97 15.89 Channel Flow, Channel -1
' Area= 4.0 sf Perim= 7.3' r= 0.55'
n= 0.080 Earth, long dense weeds
15.1 917 Total
' Subcatchment 1S: DA -1
Hydrograph

1
w
v 2

1
LL
1 1

0
5

6....7
® Runoff
Type II 24-hr 1 -year
Rainfall 2.98"
Runoff Area=14.200 ac
Runoff Volume=0.324 of
Runoff Depth>0.27"
Flow Length=917'
Tc'=15.1 min
CN=60
-gin, , "
11 12 13
Time (hours)
14 15 16 17 18 19

L

1

1

n
1

Cottonwood-POND 1 -PRE Type 1124-hr 1-year Rainfall=2.98"
Prepared by WSP SELLS Printed 4/1/2011
HydroCAD8 9.00 s/n 04719 @2009 HydroCAD Software Solutions LLC Page 6
Hydrograph for Subcatchment 1 S: DA -1
Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs)
5.00 0.19 0.00 0.00
5.25 0.20 0.00 0.00
5.50 0.21 0.00 0.00
5.75 0.23 0.00 0.00
6.00 0.24 0.00 0.00
6.25 0.25 0.00 0.00
6.50 0.27 0.00 0.00
6.75 0.28 0.00 0.00
7.00 0.30 0.00 0.00
7.25 0.31 0.00 0.00
7.50 0.33 0.00 0.00
7.75 0.34 0.00 0.00
8.00 0.36 0.00 0.00
8.25 0.37 0.00 0.00
8.50 0.39 0.00 0.00
8.75 0.42 0.00 0.00
9.00 0.44 0.00 0.00
9.25 0.46 0.00 0.00
9.50 0.49 0.00 0.00
9.75 0.51 0.00 0.00
10.00 0.54 0.00 0.00
10.25 0.57 0.00 0.00
10.50 0.61 0.00 0.00
10.75 0.65 0.00 0.00
11.00 0.70 0.00 0.00
11.25 0.76 0.00 0.00
11.50 0.84 0.00 0.00
11.75 1.15 0.00 0.00
12.00 1.98 0.06 1.31
12.25 2.10 0.08 2.27
12.50 2.19 0.10 1.24
12.75 2.25 0.11 0.85
13.00 2.30 0.12 0.71
13.25 2.34 0.13 0.62
13.50 2.38 0.14 0.56
13.75 2.41 0.15 0.51
14.00 2.44 0.16 0.46
14.25 2.47 0.17 0.42
14.50 2.50 0.17 0.41
14.75 2.52 0.18 0.39
15.00 2.54 0.19 0.38
15.25 2.57 0.19 0.36
15.50 2.59 0.20 0.35
15.75 2.60 0.20 0.33
16.00 2.62 0.21 0.31
16.25 2.64 0.21 0.29
16.50 2.66 0.22 0.29
16.75 2.67 0.22 0.28
17.00 2.69 0.23 0.28
17.25 2.70 0.23 0.27
17.50 2.72 0.24 0.26
17.75 2.73 0.24 0.26
Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs)
18.00 2.74 0.25 0.25
18.25 2.76 0.25 0.24
18.50 2.77 0.25 0.24
18.75 2.78 0.26 0.23
19.00 2.79 0.26 0.22
19.25 2.81 0.27 0.22
19.50 2.82 0.27 0.21
19.75 2.83 0.27 0.20
20.00 2.84 0.28 0.19
1

1

1
1
1
Cottonwood-POND 1 -PRE Type 11 24-hr 10-year Rainfall=5.27'
Prepared by WSP SELLS Printed 4/1/2011
HydroCAD® 9.00 s/n 04719 @2009 HydroCAD Software Solutions LLC Page 7
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: DA -1 Runoff Area=14.200 ac 0.00% Impervious Runoff Depth>1.30"
Flow Length=917' Tc=15.1 min CN=60 Runoff=24.72 cfs 1.541 of
Total Runoff Area =14.200 ac Runoff Volume =1.541 of Average Runoff Depth =1.30"
100.00% Pervious =14.200 ac 0.00% Impervious = 0.000 ac
1
Cottonwood-POND 1 -PRE Type 1124-hr 10-year Rainfall=5.27"
Prepared by WSP SELLS Printed 4/1/2011
HydroCAD® 9.00 s/n 04719 02009 HydroCAD Software Solutions LLC Page 8
Summary for Subcatchment 1S: DA -1
Runoff = 24.72 cfs @ 12.09 hrs, Volume= 1.541 af, Depth> 1.30"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 10-year Rainfall=5.27"
Area (ac) CN Description
14.200 60 Woods, Fair, HSG B
14.200 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
12.3 100 0.0700 0.14 Sheet Flow, Sheet
Woods: Light underbrush n= 0.400 P2= 3.60"
1.2 445 0.1400 6.02 Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
1.6 372 0.1020 3.97 15.89 Channel Flow, Channel -1
Area= 4.0 sf Perim= 7.3' r= 0.55'
n= 0.080 Earth, long dense weeds
15.1 917 Total
Subcatchment 1S: DA -1
Hydrograph
® Runoff
rcunorr-volume; C
w 16
Runoff Depth>1.30
3 14
il: 12 Flow Length=917'
10 Tc=15.1 min
8 "
CN=60
6 "
6 7 8 9 10 11 12 13
Time (hours)
14 15 16 17 18 19 20

0

1

Cottonwood-POND 1 -PRE Type 1124-hr 10-year Rainfall=5.27"
Prepared by WSP SELLS Printed 4/1/2011
HydroCAD® 9.00 s/n 04719 02009 HydroCAD Software Solutions LLC Page 9
Hydrograph for Subcatchment 1S: DA -1
Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs)
5.00 0.33 0.00 0.00
5.25 0.35 0.00 0.00
5.50 0.38 0.00 0.00
5.75 0.40 0.00 0.00
6.00 0.42 0.00 0.00
6.25 0.45 0.00 0.00
6.50 0.47 0.00 0.00
6.75 0.50 0.00 0.00
7.00 0.52 0.00 0.00
7.25 0.55 0.00 0.00
7.50 0.58 0.00 0.00
7.75 0.60 0.00 0.00
8.00 0.63 0.00 0.00
8.25 0.66 0.00 0.00
8.50 0.70 0.00 0.00
8.75 0.73 0.00 0.00
9.00 0.77 0.00 0.00
9.25 0.82 0.00 0.00
9.50 0.86 0.00 0.00
9.75 0.90 0.00 0.00
10.00 0.95 0.00 0.00
10.25 1.01 0.00 0.00
10.50 1.08 0.00 0.00
10.75 1.15 0.00 0.00
11.00 1.24 0.00 0.00
11.25 1.35 0.00 0.00
11.50 1.49 0.00 0.09
11.75 2.04 0.07 1.38
12.00 3.49 0.53 18.16
12.25 3.72 0.63 12.73
12.50 3.87 0.70 5.39
12.75 3.98 0.75 3.34
13.00 4.07 0.80 2.71
13.25 4.14 0.83 2.30
13.50 4.21 0.87 2.04
13.75 4.27 0.90 1.81
14.00 4.32 0.92 1.63
14.25 4.37 0.95 1.48
14.50 4.41 0.97 1.40
14.75 4.46 1.00 1.34
15.00 4.50 1.02 1.28
15.25 4.54 1.04 1.22
15.50 4.57 1.06 1.15
15.75 4.61 1.08 1.09
16.00 4.64 1.10 1.02
16.25 4.67 1.11 0.96
16.50 4.70 1.13 0.94
16.75 4.72 1.14 0.91
17.00 4.75 1.16 0.89
17.25 4.78 1.17 0.87
17.50 4.80 1.19 0.85
17.75 4.83 1.20 0.82
Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs)
18.00 4.85 1.22 0.80
18.25 4.88 1.23 0.77
18.50 4.90 1.24 0.75
18.75 4.92 1.26 0.73
19.00 4.94 1.27 0.70
19.25 4.96 1.28 0.68
19.50 4.98 1.29 0.65
19.75 5.00 1.30 0.62
20.00 5.02 1.31 0.60

Cottonwood-POND 1 -PRE Type 1124-hr 50-year Rainfall=7.09"
Prepared by WSP SELLS Printed 4/1/2011
HydroCADO 9.00 s/n 04719 © 2009 HydroCAD Software Solutions LLC Page 10
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: DA -1 Runoff Area=14.200 ac 0.00% Impervious Runoff Depth>2.41"
Flow Length=917' Tc=15.1 min CN=60 Runoff=47.47 cfs 2.857 of
Total Runoff Area =14.200 ac Runoff Volume = 2.857 of Average Runoff Depth = 2.41"
100.00% Pervious =14.200 ac 0.00% Impervious = 0.000 ac

Cottonwood-POND 1 -PRE Type// 24-hr 50-year Rainfall=7.09"
Prepared by WSP SELLS Printed 4/1/2011
HydroCAD® 9.00 s/n 04719 @2009 HydroCAD Software Solutions LLC Page 11
' Summary for Subcatchment 1S: DA -1

L

t
0
1
CI

L

Runoff = 47.47 cfs @ 12.08 hrs, Volume= 2.857 af, Depth> 2.41"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 50-year Rainfall=7.09"
Area (ac) CN Descriotion
14.200 60 Woods, Fair, HSG B
14.200 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
12.3 100 0.0700 0.14 Sheet Flow, Sheet
Woods: Light underbrush n= 0.400 P2= 3.60"
1.2 445 0.1400 6.02 Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
1.6 372 0.1020 3.97 15.89 Channel Flow, Channel -1
Area= 4.0 sf Perim= 7.3' r= 0.55'
n= 0.080 Earth, lonq dense weeds
15.1 917 Total
Subcatchment 1S: DA -1
Hydrograph
Runoff
i T- T T i T ?
5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Time (hours)

' Cottonwood-POND 1 -PRE Type// 24-hr 50-year Rainfall=7.09"
Prepared by WSP SELLS Printed 4/1/2011
HydroCADO 9.00 s/n 04719 02009 HydroCAD Software Solutions LLC Page 12
' Hydrograph for Subcatchment 1S: DA -1
1

Li
1

n
u

u
Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs)
5.00 0.45 0.00 0.00
5.25 0.48 0.00 0.00
5.50 0.51 0.00 0.00
5.75 0.54 0.00 0.00
6.00 0.57 0.00 0.00
6.25 0.60 0.00 0.00
6.50 0.63 0.00 0.00
6.75 0.67 0.00 0.00
7.00 0.70 0.00 0.00
7.25 0.74 0.00 0.00
7.50 0.77 0.00 0.00
7.75 0.81 0.00 0.00
8.00 0.85 0.00 0.00
8.25 0.89 0.00 0.00
8.50 0.94 0.00 0.00
8.75 0.99 0.00 0.00
9.00 1.04 0.00 0.00
9.25 1.10 0.00 0.00
9.50 1.16 0.00 0.00
9.75 1.22 0.00 0.00
10.00 1.28 0.00 0.00
10.25 1.36 0.00 0.00
10.50 1.45 0.00 0.05
10.75 1.55 0.01 0.19
11.00 1.67 0.02 0.41
11.25 1.82 0.03 0.74
11.50 2.01 0.06 1.35
11.75 2.74 0.25 5.07
12.00 4.70 1.13 37.40
12.25 5.01 1.30 23.22
12.50 5.21 1.43 9.36
12.75 5.35 1.51 5.67
13.00 5.47 1.59 4.56
13.25 5.58 1.65 3.86
13.50 5.66 1.71 3.41
13.75 5.74 1.76 3.02
14.00 5.81 1.80 2.70
14.25 5.88 1.84 2.44
14.50 5.94 1.88 2.31
14.75 6.00 1.92 2.20
15.00 6.05 1.96 2.10
15.25 6.10 1.99 1.99
15.50 6.15 2.02 1.89
15.75 6.20 2.05 1.78
16.00 6.24 2.08 1.67
16.25 6.28 2.11 1.57
16.50 6.32 2.13 1.52
16.75 6.36 2.16 1.48
17.00 6.39 2.18 1.44
17.25 6.43 2.21 1.41
17.50 6.46 2.23 1.37
17.75 6.50 2.25 1.33
Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs)
18.00 6.53 2.28 1.29
18.25 6.56 2.30 1.25
18.50 6.59 2.32 1.21
18.75 6.62 2.34 1.17
19.00 6.65 2.36 1.13
19.25 6.68 2.38 1.08
19.50 6.70 2.39 1.04
19.75 6.73 2.41 1.00
20.00 6.75 2.43 0.96

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