SWA000223_Design Calculations_20230810

DESIGN CALCULATIONS
FOR
Middleton Row Townhomes
Spencer, NC
PREPARED BY:
LATHAM-WALTERS ENGINEERING, INC.
16507-A NORTHCROSS DRIVE
HUNTERSVILLE, N.C. 28078
Phone: [phone] Fax: [phone]
N.C. Corporate License C-1815
FOR
Nest Communities,LLC
236 Raceway Drive-Suite 7
Mooresville, NC 28117
DATE: April 27, 2023
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STORM DRAINAGE CALCULATIONS

3/2/23,4:27 PM Precipitation Frequency Data Server
NOAA Atlas 14,Volume 2,Version 3
°°\ Location name: Salisbury,North Carolina,USA* ''''
Latitude:35.6836°,Longitude: -80.4811° none I
.175,i Elevation:mitt** i
0. *source:ESRI Maps "w
-.nu° **source:USGS "`" y
POINT PRECIPITATION FREQUENCY ESTIMATES
G.M.Bonnin,D.Martin,B.Lin,T.Parzybok,M.Yekta,and D.Riley
NOAA,National Weather Service,Silver Spring,Maryland
PF tabular I PF graphical I Maps & aerials
PF tabular
PDS-based point precipitation frequency estimates with 90% confidence intervals (in inches/hour)1
Average recurrence interval(years)
Duration
1 2 5 10 25 50 100 200 500 1000
5-min 4.61 5.46 6.36 7.00 7.70 8.17 8.59 8.94 9.32 9.58
(4.25-5.00) (5.04-5.94) (5.86-6.91) (6.43-7.58) (7.04-8.35) (7.44-8.86) (7.76-9.31) (8.04-9.72) (8.29-10.2) (8.44-10.5)
10-min 3.68 4.36 5.09 5.60 6.14 6.51 6.83 7.09 7.37 7.54
(3.40-3.99) (4.03-4.75) (4.69-5.54) (5.14-6.07) I (5.61-6.65) (5.92-7.06) (6.17-7.40) (6.37-7.70) (6.56-8.03) (6.64-8.24)
15-min 3.07 3.66 4.30 4.72 5.19 5.50 5.76 5.96 6.19 6.31
(2.83-3.33) (3.38-3.98) (3.96-4.67) (4.33-5.11) (4.74-5.62) (5.00-5.96) (5.20-6.24) (5.36-6.48) (5.50-6.74) (5.56-6.89)
30-min 2.10 2.52 3.05 3.42 3.84 4.14 4.41 4.64 4.93 I 5.11
(1.94-2.28) (2.33-2.75) (2.81-3.32) (3.14-3.70) (3.51-4.16) (3.76-4.49) (3.98-4.78) (4.17-5.05) (4.38-5.37) (4.50-5.58)
60-min 1.31 1.58 1.96 2.23 2.56 2.80 3.04 3.26 3.53 3.73
(1.21-1.42) (1.46-1.72) (1.80-2.13) (2.04-2.41) (2.34-2.77) (2.55-3.04) (2.74-3.29) (2.93-3.54) (3.14-3.85) I (3.29-4.07)
2-hr 0.756 0.914 1.14 1.30 1.52 1.68 1.84 1.99 2.19 2.33
(0.696-0.822) (0.841-0.996) (1.05-1.24) (1.19-1.42) (1.38-1.65) (1.52-1.82) (1.65-2.00) (1.77-2.17) (1.93-2.39) (2.03-2.55)
3-hr 0.535 0.647 0.809 0.930 1.09 1.21 1.34 1.46 1.62 1.74
(0.493-0.584) (0.596-0.706) (0.743-0.882) (0.852-1.01) (0.992-1.18) (1.10-1.32) (1.20-1.45) (1.30-1.58) (1.42-1.76) (1.51-1.90)
6-hr 0.325 0.392 0.489 0.564 0.665 1 0.744 0.823 0.902 1.01 1.09
(0.299-0.355) (0.361-0.428) (0.450-0.534) (0.517-0.615) (0.605-0.722)1(0.672-0.807) (0.737-0.892) (0.800-0.979) (0.882-1.10) (0.941-1.19)
12-hr 0.190 0.229 0.287 0.333 0.395 0.444 0.495 0.547 0.617 0.672
(0.175-0.207) (0.211-0.250) (0.264-0.313) (0.305-0.362) (0.359-0.428) (0.401-0.481) (0.442-0.535) (0.483-0.590) (0.536-0.666) (0.575-0.725)
24-hr 0.114 0.138 0.173 0.200 0.237 0.267 0.297 0.328 0.371 0.404
(0.107-0.122) (0.129-0.147) (0.161-0.185) (0.187-0.214) (0.221-0.254) (0.248-0.286) (0.276-0.318) (0.303-0.352) (0.341-0.397) (0.370-0.433)
2-day 0.066 0.079 0.099 0.114 0.135 0.151 0.167 ' 0.184 0.207 0.225
(0.062-0.070) (0.075-0.085) (0.093-0.106) (0.107-0.122) (0.126-0.143) (0.140-0.161) (0.155-0.178)1(0.170-0.197) (0.191-0.221) (0.206-0.240)
3-day 0.047 0.056 0.070 0.080 0.095 0.106 0.117 0.129 0.145 0.158
(0.044-0.050) (0.053-0.060) (0.065-0.074) (0.075-0.085) (0.088-0.101) (0.099-0.113) (0.109-0.125) (0.120-0.138) (0.134-0.155) (0.145-0.168)
4-day 0.037 0.045 0.055 0.063 0.074 0.083 0.092 0.102 0.114 I 0.124
(0.035-0.040) (0.042-0.048) (0.052-0.059) (0.059-0.067) (0.070-0.079) (0.078-0.089) (0.086-0.098) (0.094-0.108) (0.105-0.122) (0.114-0.132)
7-day 0.025 0.029 0.036 0.041 0.048 0.053 0.059 0.064 0.072 0.078
(0.023-0.026) (0.028-0.031) (0.034-0.038) (0.038-0.043) (0.045-0.050) (0.050-0.056) (0.055-0.062) (0.060-0.068) (0.067-0.077) (0.072-0.083)
10-day 0.020 0.023 0.028 0.032 0.037 0.040 0.044 0.048 0.054 0.058
(0.019-0.021) (0.022-0.025) (0.027-0.030) (0.030-0.033) (0.035-0.039) (0.038-0.043) (0.042-0.047) (0.045-0.051) (0.050-0.057) (0.054-0.061)
20-day 0.013 0.016 0.018 0.021 0.024 0.026 0.028 0.031 0.034 0.036
(0.013-0.014) (0.015-0.016) (0.018-0.019) (0.020-0.022) (0.022-0.025) (0.025-0.027) (0.027-0.030) (0.029-0.032) (0.032-0.036) (0.034-0.038)
30-day 0.011 0.013 0.015 0.016 0.019 0.020 0.022 0.023 0.025 0.027
(0.010-0.011) (0.012-0.013) (0.014-0.016) (0.016-0.017) (0.018-0.019) (0.019-0.021) (0.021-0.023) (0.022-0.024) (0.024-0.027) (0.025-0.028)
45-day 0.009 0.011 0.012 0.013 0.015 0.016 0.017 0.018 0.020 0.021
(0.009-0.010) (0.010-0.011) (0.012-0.013) (0.013-0.014) (0.014-0.015) (0.015-0.017) (0.016-0.018) (0.017-0.019) (0.019-0.020) (0.020-0.022)
60-day 0.008 0.009 0.011 0.012 0.013 0.014 0.015 0.015 0.017 0.017
(0.008-0.008) (0.009-0.010) (0.010-0.011) (0.011-0.012) (0.012-0.013) (0.013-0.014) (0.014-0.015) (0.015-0.016) (0.016-0.017) (0.017-0.018)1
1 Precipitation frequency(PF)estimates in this table are based on frequency analysis of partial duration series(PDS).
Numbers in parenthesis are PF estimates at lower and upper bounds of the 90%confidence interval.The probability that precipitation frequency estimates(for
a given duration and average recurrence interval)will be greater than the upper bound(or less than the lower bound)is 5%.Estimates at upper bounds are not
checked against probable maximum precipitation(PMP)estimates and may be higher than currently valid PMP values.
Please refer to NOAA Atlas 14 document for more information.
Back to Top
PF graphical
https://hdsc.nws.noaa.gov/hdsc/pfds/pfds_printpage.html?lat=35.6836&Ion=-80.4811&data=intensity&units=english&series=pds 1/4

Dschedule Pagel
Line Inlet Gnd/Rim Drng Total Runoff i i Flow Invert Invert Capac Line Line Line Vel Line Depth Depth Cover
No. ID El Up Area Area Coeff Inlet Sys Rate Up Dn Full Size Length Slope Dn ID Dn Up Up
(ft) (ac) (ac) (C) (in/hr) (in/hr) (cfs) (ft) (ft) (cfs) (in) (ft) (%) (ft/s) (ft) (ft) (ft)
3 CB-2 651.14 0.46 0.46 0.65 6.80 6.80 2.03 647.82 646.72 6.46 15 110.000 1.00 4.04 3 0.54 0.57** 2.07
2 CB-3 650.07 0.31 0.77 0.65 6.80 6.68 3.34 646.52 646.00 8.96 15 27.000 1.93 3.21 2 0.99 0.74"" 2.30
1 CB-1 649.54 0.24 0.24 0.70 6.80 6.80 1.14 646.50 646.00 9.32 15 24.000 2.08 5.04 1 0.30 0.42** 1.79
Project File: Storm System.stm Number of lines: 3 Date: 4/26/2023
NOTES: Intensity=206.38/(Inlet time+22.60)A 1.03--Return period= 10 Yrs. ; ""Critical depth
Storm Sewers

EROSION CONTROL CALCULATIONS

Middleton Row Townhomes INPUT
Spencer, NC
Erosion Control Basin No. 1
Skimmer Sediment Basin Drainage Area 2.13
NCDEQ Disturbed Area 2.13
C 0.6
Time of Concentration 5
Intensity 7
1. Basin No. 1 Weir Depth 1.0
Weir Length 10
2. Determine Runoff for 10-Year Storm
Q= CIA 8.9 C.F.S.
3. Determine Storage Capacity Required:
1800 CF/AC x Disturbed Area= Storage Volume
Storage Volume= 3834 cf Note: LESS THAN 10 AC. DISTURBED
4. Size Basin:
Surface Area= (Q10 x325) = 2907.45 S.F. 4391.00 S.F. @ EL. 646
Length =2 x Width
Width 38.1 Feet See plans for actual irregular configuration.
Length 76.3 Feet
Depth 1.32 Feet
Actual Volume = 5343.00 Cubic Feet (from the plans) Elevation Area Volume Total Vol.
644.5 400 0 0
5. Embankment 645 770 292.5 292.5
646 4391 2580.5 2873
Depth to Weir 2.0 FEET 647 5489 4940 7813
Depth to Top of Embankment 4.0 FEET 648 6644 6066.5 13879.5
3:1 Side Slopes 648.5 Top of Dam
8'Top Width
6. Design Spillway for Q10 utilizing the Weir Equation with 1' of Freeboard.
Q=3.0(L)(H^1.5) where L=Length of Weir= 10 feet
H= Depth of Weir= 1.0 feet
Qcapacity= 30.0 cfs
Q 10= 8.9 cfs < Qcapacity- OK

9. Basin Dewatering/Skimmer Sizing:
Q=cA(2gH)^1/2
Skimmer Device Size= 1.50 " Diameter
Skimmer Orifice Size= 1.25 " (This may be reduced if required)
Amount of Skimmers= 1
Head on Orifice= 0.125 ft
QD= 0.01450 cfs 1252.82 cf/day
Volume: 3834 cf
Drawdown time= 73.45 Hrs 3.060286 (48-120 hours Required)
Drawdown per hour= 0.03 feet

SAND FILTER CALCULATIONS

TR 55 Urban Hydrology for Small Watershed LATHAM-WALTERS ENGINEERING, INC.
Time of Concentration &Travel Time 16507-A Northcross Drive
Middleton Row Townhomes Huntersville, NC 28078
Spencer, NC [phone]
Pre-Developed
Tc for Proposed Drainage Area-Basin#1
Tc=T1 +T2 + T3 Time of Concentration
1. Sheet Flow:
T1 = (0.007 x (nL)^0.8))/((P2)^0.5 x s^0.4)
0.24 n Manning's Coefficient for Grass
100 L Flow Length Travel (100' max. urban, 300' max rural)
3.31 P2 2 Year- 24 Hour Rainfall for Spencer, NC
3.10% s Slope of hydraulic grade line
0.196 T1 Travel Time (hr.)
2. Shallow Concentrated Flow
V2 = (16.1345*s^0.5) Unpaved
V2 = (20.3282*s^0.5) Paved
0 Length of Paved Flow
141 Length of Unpaved Flow
1.99% Slope of Paved Flow
2.13% Slope of Unpaved Flow
2.355 V2 - Unpaved (fps)
2.868 V2 - Paved (fps)
0.000 T2 Paved (seconds)
59.879 T2 Unpaved (seconds)
0.017 T2 Total (hours)
3. Pipe Flow
V= (1.49 x (r)^0.67 x (s)^0.5)/n Velocity from Manning's Equation (fps)
24 d -diameter of pipe, in.
0.5 r- hydraulic radius, ft;Area/Wetted Perimeter
0.034 s-slope of hydraulic grade line, (ft/ft)
0.013 n - Manning's roughness coefficient
13.314 V-velocity in fps
0 Length of Flow (ft.)
0.000 T3 (hrs.) Length/Velocity/3600
0.213 Tc=T1 +T2+T3 +T4 (hrs.)
12.77 Total Tc (minutes)
Pre Developed Tc = 12.77 minutes
Post Developed Tc= 5 minutes

Middleton Row Townhomes Latham-Walters Engineering, Inc.
Basin#1 16507-A Northcross Drive
Spencer, NC Huntersville, NC 28078
Weighted Curve Number Calculations
Pre-Developed Soil Types C ChA, DoB 2.30 Ac.
2.30 Acres Total
Post Developed Soils Type:
Hydrologic Soils Group: C ChA, DoB 2.30 Ac.
Ac.
2.30 Acres Total
Pre-Developed:
Drainage Area Cn Product Description
2.30 Ac. 73 167.9 Wooded C Soil
98 0 Paved
2.30 Total 167.9 Sum
Composite Cn 73.0 Pre-Developed
Post-Developed:
Basin 2S
Drainage Area Cn Product Description
0.99 Ac. 98 97.02 Impervious Area C Soils
0.00 Ac. 73 0 Wooded C Soils
1.31 Ac. 79 103.49 Open Space C Soils
2.30 200.51 Sum
Composite Cn 87.2 Post-Developed

Middleton Row Townhomes Latham-Walters Engineering, Inc.
16507-A Northcross Drive
Spencer, NC Huntersville, NC 28078
1. Develop Stage-Discharge Data for Sand Filter Media.
From 4.8.18 of the BMP Standards Manual:
Q =Af(k)(h+df)/(df)
where Af = surface area of filter bed = 400 sf
df =filter bed depth, ft. = 1.5 ft.
k =coefficient of permeability of filter media (ft/day) = 4 ft/day
h = average height of water above filter bed (ft) 1,2, etc.
h Q Q
cf/day cfs
1 2666.667 0.031
2 3733.333 0.043
3 4800 0.056
4 5866.667 0.068
5 6933.333 0.080
6 8000 0.093
7 9066.667 0.105
8 10133.33 0.117
9 11200 0.130
10 12266.67 0.142

Middleton Row Townhomes
Sand Filter Calculation - NCDEQ Design Manual
Basin# 1
1. Calculate Runoff Coeff,(Rv)
Drainage area to filter,Ad= 2.30 ac
Impervious area to filter forebay= 0.99 ac.
Impervious percentage= 43.04% to basin
Rv=0.05+0.9(%Imp) = 0.4373913
2. Calculate req'd water quality volume(WQV) WQV=(Rv/1 x Ad/1 x 43560 sf/1 ac x Rd/1 x ft/12 in)
WQV= 3652 cf (used to size Af)
WQVADJ= 2739 cf
WQV= 0.0629 ac-ft.
Storaqe: Area Vol. Cum vol
644.5 400 0 0
645 770 292.5 292.5
646 4391 2580.5 2873
647 5489 4940 7813
648 6644 6066.5 13879.5
648.5 Top of Dam
Calculate Depth for WQ Volume:
645 292.5
645.95 2739
646 2873
7813
Elevation of WQ Volume= 645.95 (hA for the 1 inch storm)
3. Calculate the minimum surface area for the Sand Filter&Sediment Chamber
Af(ft2):[WQV x dF]/[(k)(t)(hA+dF)]= 371 sf 400 sf Total Area of Filter
hMaxFilter(ft): 1.45 2' Provided
dF 1.5 ft hA(ft): 0.7 1' Provided
hA 0.724004069 ft.
k 4 ft/day Note: Provided information input into Sand Filter
1.66 days Supplement document based on
design;0.65 hmax based on volume
Compute Minimum Pre-Treatment Volume(20%of WQ Volume)
20%of WQ Volume: 548 cf

4. Water Quality Peak Flow(WQp)from HydroCad: 0.04 cfs from HydroCad 1"-24 Hour Storm
5. Underdrain Calculations:
Q: Flow Rate through Soil Media with a Safety Factor of 10: 0.4321
D= 16[(Q x n)/(5°5)](3/8) 5.81338
n 0.011
S 0.5%
70 I.f of underdrain shown; provide 6"perforated pvc pipe with 3/8"perforations spaces 6"o.c. -4 longitudinal rows
spaced 90 degrees apart. Minimum slope is 0.5%
70 I.f. of pipe
70 I.f.x 4 rows/ft x 4 holes/ft= 840 holes
50%of perforations= 420 holes
Capacity of one hole= 0.0083 cfs based upon CA(2gh)^0.5
Total Capacity= 3.486 cfs which is 62.7 times the capacity of the sand filter.
Total Capacityof 6" PVC @ 0.50%is 2.7 cfs(1.35 cfs assuming 50%clogged) from Mannings and BMP Manual.
6.Stormwater Detention
Storm Pre-Developed Post Developed Routed Peak
Runoff(cfs) Runoff(cfs) Flow(cfs) Stage
1" 0 0.87 0.03 645.43
2 Year _ 3.9 8.19 3.16 646.68
10 Year 6.76 13.45 6.41 647.33
100 Year 12.87 21.6 19.52 647.63

1S
Pre-developed
2S > 3P
post-developed Wet Pond
(Subc Reach Pon Link Drainage Diagram for 2302-Pond 1
Prepared by{enter your company name here} 6/19/2023
HydroCAD®8.00 s/n 004317 ©2006 HydroCAD Software Solutions LLC

2302-Pond 1
Prepared by (enter your company name here} Page 2
HydroCAD®8.00 s/n 004317 ©2006 HydroCAD Software Solutions LLC 6/19/2023
Area Listing (all nodes)
Area (acres) CN Description (subcats)
2.300 73 Woods, Fair, HSG C (1 S)
1.310 79 50-75% Grass cover, Fair, HSG C (2S)
0.990 98 Bldg/Pave (2S)
4.600

2302-Pond 1 Type 1124-hr linch Rainfall=1.00"
Prepared by {enter your company name here} Page 3
HydroCAD®8.00 s/n 004317 ©2006 HydroCAD Software Solutions LLC 6/19/2023
Time span=0.00-72.00 hrs, dt=0.05 hrs, 1441 points
Runoff by SCS TR-20 method, UH=SCS
Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method
Subcatchment 1S: Pre-developed Runoff Area=2.300 ac Runoff Depth=0.02"
Tc=12.8 min CN=73 Runoff=0.00 cfs 0.003 af
Subcatchment 2S: post-developed Runoff Area=2.300 ac Runoff Depth=0.22"
Tc=5.0 min CN=87 Runoff=0.87 cfs 0.043 af
Pond 3P: Wet Pond Peak Elev=645.43' Storage=948 cf Inflow=0.87 cfs 0.043 af
Primary=0.03 cfs 0.043 af Secondary=0.00 cfs 0.000 af Outflow=0.03 cfs 0.043 af
Total Runoff Area = 4.600 ac Runoff Volume= 0.046 of Average Runoff Depth = 0.12"
78.48% Pervious Area = 3.610 ac 21.52%Impervious Area = 0.990 ac

2302-Pond 1 Type 1124-hr linch Rainfall=1.00"
Prepared by {enter your company name here} Page 4
HydroCAD®8.00 s/n 004317 ©2006 HydroCAD Software Solutions LLC 6/19/2023
Subcatchment 1 S: Pre-developed
Runoff = 0.00 cfs @ 15.30 hrs, Volume= 0.003 af, Depth= 0.02"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs
Type II 24-hr 1 inch Rainfall=1.00"
Area (ac) CN Description
2.300 73 Woods, Fair, HSG C
2.300 Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
12.8 Direct Entry,

2302-Pond 1 Type 1124-hr linch Rainfall=1.00"
Prepared by {enter your company name here} Page 5
HydroCAD®8.00 s/n 004317 ©2006 HydroCAD Software Solutions LLC 6/19/2023
Hydrograph for Subcatchment 1S: Pre-developed
Time Precip. Excess Runoff Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs) (hours) (inches) (inches) (cfs)
0.00 0.00 0.00 0.00 52.00 1.00 0.02 0.00
1.00 0.01 0.00 0.00 53.00 1.00 0.02 0.00
2.00 0.02 0.00 0.00 54.00 1.00 0.02 0.00
3.00 0.03 0.00 0.00 55.00 1.00 0.02 0.00
4.00 0.05 0.00 0.00 56.00 1.00 0.02 0.00
5.00 0.06 0.00 0.00 57.00 1.00 0.02 0.00
6.00 0.08 0.00 0.00 58.00 1.00 0.02 0.00
7.00 0.10 0.00 0.00 59.00 1.00 0.02 0.00
8.00 0.12 0.00 0.00 60.00 1.00 0.02 0.00
9.00 0.15 0.00 0.00 61.00 1.00 0.02 0.00
10.00 0.18 0.00 0.00 62.00 1.00 0.02 0.00
11.00 0.24 0.00 0.00 63.00 1.00 0.02 0.00
12.00 0.66 0.00 0.00 64.00 1.00 0.02 0.00
13.00 0.77 0.00 0.00 65.00 1.00 0.02 0.00
14.00 0.82 0.00 0.00 66.00 1.00 0.02 0.00
15.00 0.85 0.00 0.00 67.00 1.00 0.02 0.00
16.00 0.88 0.01 0.00 68.00 1.00 0.02 0.00
17.00 0.90 0.01 0.00 69.00 1.00 0.02 0.00
18.00 0.92 0.01 0.00 70.00 1.00 0.02 0.00
19.00 0.94 0.01 0.00 71.00 1.00 0.02 0.00
20.00 0.95 0.01 0.00 72.00 1.00 0.02 0.00
21.00 0.96 0.01 0.00
22.00 0.98 0.01 0.00
23.00 0.99 0.02 0.00
24.00 1.00 0.02 0.00
25.00 1.00 0.02 0.00
26.00 1.00 0.02 0.00
27.00 1.00 0.02 0.00
28.00 1.00 0.02 0.00
29.00 1.00 0.02 0.00
30.00 1.00 0.02 0.00
31.00 1.00 0.02 0.00
32.00 1.00 0.02 0.00
33.00 1.00 0.02 0.00
34.00 1.00 0.02 0.00
35.00 1.00 0.02 0.00
36.00 1.00 0.02 0.00
37.00 1.00 0.02 0.00
38.00 1.00 0.02 0.00
39.00 1.00 0.02 0.00
40.00 1.00 0.02 0.00
41.00 1.00 0.02 0.00
42.00 1.00 0.02 0.00
43.00 1.00 0.02 0.00
44.00 1.00 0.02 0.00
45.00 1.00 0.02 0.00
46.00 1.00 0.02 0.00
47.00 1.00 0.02 0.00
48.00 1.00 0.02 0.00
49.00 1.00 0.02 0.00
50.00 1.00 0.02 0.00
51.00 1.00 0.02 0.00

2302-Pond 1 Type 1124-hr linch Rainfall=1.00"
Prepared by {enter your company name here} Page 6
HydroCAD®8.00 s/n 004317 ©2006 HydroCAD Software Solutions LLC 6/19/2023
Subcatchment 2S: post-developed
Runoff = 0.87 cfs @ 11.97 hrs, Volume= 0.043 af, Depth= 0.22"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs
Type II 24-hr 1 inch Rainfall=1.00"
Area (ac) CN Description
1.310 79 50-75% Grass cover, Fair, HSG C
0.990 98 Bldg/Pave
2.300 87 Weighted Average
1.310 Pervious Area
0.990 Impervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry, post

2302-Pond 1 Type 1124-hr linch Rainfall=1.00"
Prepared by {enter your company name here} Page 7
HydroCAD®8.00 s/n 004317 ©2006 HydroCAD Software Solutions LLC 6/19/2023
Hydrograph for Subcatchment 2S: post-developed
Time Precip. Excess Runoff Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs) (hours) (inches) (inches) (cfs)
0.00 0.00 0.00 0.00 52.00 1.00 0.22 0.00
1.00 0.01 0.00 0.00 53.00 1.00 0.22 0.00
2.00 0.02 0.00 0.00 54.00 1.00 0.22 0.00
3.00 0.03 0.00 0.00 55.00 1.00 0.22 0.00
4.00 0.05 0.00 0.00 56.00 1.00 0.22 0.00
5.00 0.06 0.00 0.00 57.00 1.00 0.22 0.00
6.00 0.08 0.00 0.00 58.00 1.00 0.22 0.00
7.00 0.10 0.00 0.00 59.00 1.00 0.22 0.00
8.00 0.12 0.00 0.00 60.00 1.00 0.22 0.00
9.00 0.15 0.00 0.00 61.00 1.00 0.22 0.00
10.00 0.18 0.00 0.00 62.00 1.00 0.22 0.00
11.00 0.24 0.00 0.00 63.00 1.00 0.22 0.00
12.00 0.66 0.07 0.82 64.00 1.00 0.22 0.00
13.00 0.77 0.11 0.06 ' 65.00 1.00 0.22 0.00
14.00 0.82 0.13 0.04 66.00 1.00 0.22 0.00
15.00 0.85 0.15 0.03 67.00 1.00 0.22 0.00
16.00 0.88 0.16 0.03 68.00 1.00 0.22 0.00
17.00 0.90 0.17 0.02 69.00 1.00 0.22 0.00
18.00 0.92 0.18 0.02 70.00 1.00 0.22 0.00
19.00 0.94 0.19 0.02 71.00 1.00 0.22 0.00
20.00 0.95 0.20 0.02 72.00 1.00 0.22 0.00
21.00 0.96 0.21 0.02
22.00 0.98 0.21 0.01
23.00 0.99 0.22 0.01
24.00 1.00 0.22 0.01
25.00 1.00 0.22 0.00
26.00 1.00 0.22 0.00
27.00 1.00 0.22 0.00
28.00 1.00 0.22 0.00
29.00 1.00 0.22 0.00
30.00 1.00 0.22 0.00
31.00 1.00 0.22 0.00
32.00 1.00 0.22 0.00
33.00 1.00 0.22 0.00
34.00 1.00 0.22 0.00
35.00 1.00 0.22 0.00
36.00 1.00 0.22 0.00
37.00 1.00 0.22 0.00
38.00 1.00 0.22 0.00
39.00 1.00 0.22 0.00
40.00 1.00 0.22 0.00
41.00 1.00 0.22 0.00
42.00 1.00 0.22 0.00
43.00 1.00 0.22 0.00
44.00 1.00 0.22 0.00
45.00 1.00 0.22 0.00
46.00 1.00 0.22 0.00
47.00 1.00 0.22 0.00
48.00 1.00 0.22 0.00
49.00 1.00 0.22 0.00
50.00 1.00 0.22 0.00
51.00 1.00 0.22 0.00

2302-Pond 1 Type 1124-hr linch Rainfall=1.00"
Prepared by {enter your company name here} Page 8
HydroCAD®8.00 s/n 004317 ©2006 HydroCAD Software Solutions LLC 6/19/2023
Pond 3P: Wet Pond
Inflow Area = 2.300 ac, Inflow Depth = 0.22" for 1 inch event
Inflow = 0.87 cfs @ 11.97 hrs, Volume= 0.043 af
Outflow = 0.03 cfs @ 15.65 hrs, Volume= 0.043 af, Atten= 97%, Lag= 220.9 min
Primary = 0.03 cfs @ 15.65 hrs, Volume= 0.043 af
Secondary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af
Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs
Peak Elev= 645.43' @ 15.65 hrs Surf.Area= 2,310 sf Storage= 948 cf
Plug-Flow detention time= 450.4 min calculated for 0.043 af (100% of inflow)
Center-of-Mass det. time= 451.3 min ( 1,332.0 - 880.7 )
Volume Invert Avail.Storage Storage Description
#1 644.50' 13,880 cf Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic-feet) (cubic-feet)
644.50 400 0 0
645.00 770 293 293
646.00 4,391 2,581 2,873
647.00 5,489 4,940 7,813
648.00 6,644 6,067 13,880
Device Routing Invert Outlet Devices
#1 Primary 641.75' 18.0" x 50.0' long Culvert Ke= 0.200
Outlet Invert= 641.25' S= 0.0100 '/' Cc= 0.900 n= 0.012
#2 Device 1 644.50' Special & User-Defined
Head (feet) 0.00 1.00 2.00 3.00 4.00 5.00 6.00
Disch. (cfs) 0.000 0.031 0.043 0.056 0.068 0.080 0.093
#3 Device 1 645.50' 12.0" Vert. Orifice/Grate C= 0.600
#4 Device 1 647.20' 16.0' long x 0.5' breadth Broad-Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00
Coef. (English) 2.80 2.92 3.08 3.30 3.32
#5 Secondary 647.50' 10.0' long x 12.0' 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) 2.57 2.62 2.70 2.67 2.66 2.67 2.66 2.64
Primary OutFlow Max=0.03 cfs @ 15.65 hrs HW=645.43' (Free Discharge)
L1=Culvert (Passes 0.03 cfs of 16.49 cfs potential flow)
2=Special & User-Defined (Custom Controls 0.03 cfs)
3=Orifice/Grate ( Controls 0.00 cfs)
4=Broad-Crested Rectangular Weir ( Controls 0.00 cfs)
Secondary OutFlow Max=0.00 cfs @ 0.00 hrs HW=644.50' (Free Discharge)
4-5=Broad-Crested Rectangular Weir ( Controls 0.00 cfs)

2302-Pond 1 Type 1124-hr linch Rainfall=1.00"
Prepared by {enter your company name here} Page 9
HydroCAD®8.00 s/n 004317 ©2006 HydroCAD Software Solutions LLC 6/19/2023
Hydrograph for Pond 3P: Wet Pond
Time Inflow Storage Elevation Outflow Primary Secondary
(hours) (cfs) (cubic-feet) (feet) (cfs) (cfs) (cfs)
0.00 0.00 0 644.50 0.00 0.00 0.00
2.50 0.00 0 644.50 0.00 0.00 0.00
5.00 0.00 0 644.50 0.00 0.00 0.00
7.50 0.00 0 644.50 0.00 0.00 0.00
10.00 0.00 0 644.50 0.00 0.00 0.00
12.50 0.10 747 645.33 0.03 0.03 0.00
15.00 0.03 944 645.42 0.03 0.03 0.00
17.50 0.02 924 645.41 0.03 0.03 0.00
20.00 0.02 846 645.38 0.03 0.03 0.00
22.50 0.01 743 645.33 0.03 0.03 0.00
25.00 0.00 600 645.25 0.02 0.02 0.00
27.50 0.00 409 645.12 0.02 0.02 0.00
30.00 0.00 258 644.95 0.01 0.01 0.00
32.50 0.00 154 644.80 0.01 0.01 0.00
35.00 0.00 87 644.69 0.01 0.01 0.00
37.50 0.00 47 644.61 0.00 0.00 0.00
40.00 0.00 25 644.56 0.00 0.00 0.00
42.50 0.00 13 644.53 0.00 0.00 0.00
45.00 0.00 7 644.52 0.00 0.00 0.00
47.50 0.00 3 644.51 0.00 0.00 0.00
50.00 0.00 2 644.50 0.00 0.00 0.00
52.50 0.00 1 644.50 0.00 0.00 0.00
55.00 0.00 0 644.50 0.00 0.00 0.00
57.50 0.00 0 644.50 0.00 0.00 0.00
60.00 0.00 0 644.50 0.00 0.00 0.00
62.50 0.00 0 644.50 0.00 0.00 0.00
65.00 0.00 0 644.50 0.00 0.00 0.00
67.50 0.00 0 644.50 0.00 0.00 0.00
70.00 0.00 0 644.50 0.00 0.00 0.00

2302-Pond 1 Type 1124-hr linch Rainfall=1.00"
Prepared by {enter your company name here} Page 10
HydroCAD®8.00 s/n 004317 ©2006 HydroCAD Software Solutions LLC 6/19/2023
Stage-Discharge for Pond 3P: Wet Pond
Elevation Discharge Primary Secondary Elevation Discharge Primary Secondary
(feet) (cfs) (cfs) (cfs) ' (feet) (cfs) (cfs) (cfs)
644.50 0.00 0.00 0.00 649.70 112.72 26.57 86.15
644.60 0.00 0.00 0.00 649.80 118.85 26.77 92.09
644.70 0.01 0.01 0.00 649.90 125.11 26.95 98.16
644.80 0.01 0.01 0.00 650.00 131.50 27.14 104.36
644.90 0.01 0.01 0.00 650.10 138.01 27.33 110.68
645.00 0.02 0.02 0.00 650.20 144.64 27.51 117.12
645.10 0.02 0.02 0.00 650.30 151.39 27.70 123.69
645.20 0.02 0.02 0.00 650.40 158.26 27.88 130.38
645.30 0.02 0.02 0.00 650.50 165.24 28.06 137.18
645.40 0.03 0.03 0.00
645.50 0.03 0.03 0.00
645.60 0.08 0.08 0.00
645.70 0.20 0.20 0.00
645.80 0.40 0.40 0.00
645.90 0.67 0.67 0.00
646.00 0.98 0.98 0.00
646.10 1.34 1.34 0.00
646.20 1.71 1.71 0.00
646.30 2.09 2.09 0.00
646.40 2.45 2.45 0.00
646.50 2.72 2.72 0.00
646.60 2.97 2.97 0.00
646.70 3.21 3.21 0.00
646.80 3.43 3.43 0.00
646.90 3.64 3.64 0.00
647.00 3.83 3.83 0.00
647.10 4.02 4.02 0.00
647.20 4.19 4.19 0.00
647.30 5.78 5.78 0.00
647.40 8.54 8.54 0.00
647.50 12.21 12.21 0.00
647.60 17.47 16.66 0.81
647.70 24.26 21.96 2.30
647.80 26.92 22.65 4.26
647.90 29.50 22.88 6.63
648.00 32.50 23.10 9.40
648.10 35.86 23.32 12.55
648.20 39.26 23.53 15.73
648.30 42.85 23.75 19.10
648.40 46.72 23.96 22.75
648.50 50.77 24.17 26.60
648.60 55.13 24.38 30.75
648.70 59.69 24.59 35.10
648.80 64.30 24.79 39.50
648.90 69.06 25.00 44.06
649.00 73.88 25.20 48.68
649.10 78.83 25.40 53.43
649.20 84.12 25.60 58.52
649.30 89.55 25.80 63.75
649.40 95.14 25.99 69.14
649.50 100.86 26.19 74.67
649.60 106.72 26.38 80.34

2302-Pond 1 Type 1124-hr 2 Year-Spencer Rainfall=3.31"
Prepared by {enter your company name here} Page 11
HydroCAD®8.00 s/n 004317 ©2006 HydroCAD Software Solutions LLC 6/19/2023
Time span=0.00-72.00 hrs, dt=0.05 hrs, 1441 points
Runoff by SCS TR-20 method, UH=SCS
Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method
Subcatchment 1S: Pre-developed Runoff Area=2.300 ac Runoff Depth=1.05"
Tc=12.8 min CN=73 Runoff=3.23 cfs 0.202 af
Subcatchment 2S: post-developed Runoff Area=2.300 ac Runoff Depth=2.01"
Tc=5.0 min CN=87 Runoff=8.19 cfs 0.386 af
Pond 3P: Wet Pond Peak Elev=646.68' Storage=6,097 cf Inflow=8.19 cfs 0.386 af
Primary=3.16 cfs 0.386 af Secondary=0.00 cfs 0.000 af Outflow=3.16 cfs 0.386 af
Total Runoff Area = 4.600 ac Runoff Volume= 0.588 of Average Runoff Depth = 1.53"
78.48% Pervious Area = 3.610 ac 21.52%Impervious Area = 0.990 ac

2302-Pond 1 Type 1124-hr 2 Year-Spencer Rainfall=3.31"
Prepared by {enter your company name here} Page 12
HydroCAD®8.00 s/n 004317 ©2006 HydroCAD Software Solutions LLC 6/19/2023
Subcatchment 1 S: Pre-developed
Runoff = 3.23 cfs @ 12.06 hrs, Volume= 0.202 af, Depth= 1.05"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs
Type II 24-hr 2 Year-Spencer Rainfall=3.31"
Area (ac) CN Description
2.300 73 Woods, Fair, HSG C
2.300 Pervious Area
Tc Length Slope Velocity Capacity Description
(min) _ (feet) (ft/ft) (ft/sec) (cfs) _
12.8 Direct Entry,

2302-Pond 1 Type 1124-hr 2 Year-Spencer Rainfall=3.31"
Prepared by {enter your company name here} Page 13
HydroCAD®8.00 s/n 004317 ©2006 HydroCAD Software Solutions LLC 6/19/2023
Hydrograph for Subcatchment 1S: Pre-developed
Time Precip. Excess Runoff Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs) (hours) (inches) (inches) (cfs)
0.00 0.00 0.00 0.00 52.00 3.31 1.05 0.00
1.00 0.03 0.00 0.00 53.00 3.31 1.05 0.00
2.00 0.07 0.00 0.00 54.00 3.31 1.05 0.00
3.00 0.11 0.00 0.00 55.00 3.31 1.05 0.00
4.00 0.16 0.00 0.00 56.00 3.31 1.05 0.00
5.00 0.21 0.00 0.00 57.00 3.31 1.05 0.00
6.00 0.26 0.00 0.00 58.00 3.31 1.05 0.00
7.00 0.33 0.00 0.00 59.00 3.31 1.05 0.00
8.00 0.40 0.00 0.00 60.00 3.31 1.05 0.00
9.00 0.49 0.00 0.00 61.00 3.31 1.05 0.00
10.00 0.60 0.00 0.00 62.00 3.31 1.05 0.00
11.00 0.78 0.00 0.00 63.00 3.31 1.05 0.00
12.00 2.19 0.41 2.76 64.00 3.31 1.05 0.00
13.00 2.56 0.60 0.30 65.00 3.31 1.05 0.00
14.00 2.71 0.69 0.18 66.00 3.31 1.05 0.00
15.00 2.83 0.75 0.14 67.00 3.31 1.05 0.00
16.00 2.91 0.80 0.11 68.00 3.31 1.05 0.00
17.00 2.98 0.85 0.10 69.00 3.31 1.05 0.00
18.00 3.05 0.89 0.09 70.00 3.31 1.05 0.00
19.00 3.10 0.92 0.08 71.00 3.31 1.05 0.00
20.00 3.15 0.95 0.07 72.00 3.31 1.05 0.00
21.00 3.19 0.98 0.06
22.00 3.23 1.00 0.06
23.00 3.27 1.03 0.06
24.00 3.31 1.05 0.06
25.00 3.31 1.05 0.00
26.00 3.31 1.05 0.00
27.00 3.31 1.05 0.00
28.00 3.31 1.05 0.00
29.00 3.31 1.05 0.00
30.00 3.31 1.05 0.00
31.00 3.31 1.05 0.00
32.00 3.31 1.05 0.00
33.00 3.31 1.05 0.00
34.00 3.31 1.05 0.00
35.00 3.31 1.05 0.00
36.00 3.31 1.05 0.00
37.00 3.31 1.05 0.00
38.00 3.31 1.05 0.00
39.00 3.31 1.05 0.00
40.00 3.31 1.05 0.00
41.00 3.31 1.05 0.00
42.00 3.31 1.05 0.00
43.00 3.31 1.05 0.00
44.00 3.31 1.05 0.00
45.00 3.31 1.05 0.00
46.00 3.31 1.05 0.00
47.00 3.31 1.05 0.00
48.00 3.31 1.05 0.00
49.00 3.31 1.05 0.00
50.00 3.31 1.05 0.00
51.00 3.31 1.05 0.00

2302-Pond 1 Type 1124-hr 2 Year-Spencer Rainfall=3.31"
Prepared by {enter your company name here} Page 14
HydroCAD®8.00 s/n 004317 ©2006 HydroCAD Software Solutions LLC 6/19/2023
Subcatchment 2S: post-developed
Runoff = 8.19 cfs @ 11.96 hrs, Volume= 0.386 af, Depth= 2.01"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs
Type II 24-hr 2 Year-Spencer Rainfall=3.31"
Area (ac) CN Description
1.310 79 50-75% Grass cover, Fair, HSG C
0.990 98 Bldg/Pave
2.300 87 Weighted Average
1.310 Pervious Area
0.990 Impervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry, post

2302-Pond 1 Type 1124-hr 2 Year-Spencer Rainfall=3.31"
Prepared by {enter your company name here} Page 15
HydroCAD®8.00 s/n 004317 ©2006 HydroCAD Software Solutions LLC 6/19/2023
Hydrograph for Subcatchment 2S: post-developed
Time Precip. Excess Runoff Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs) (hours) (inches) (inches) (cfs)
0.00 0.00 0.00 0.00 52.00 3.31 2.01 0.00
1.00 0.03 0.00 0.00 53.00 3.31 2.01 0.00
2.00 0.07 0.00 0.00 54.00 3.31 2.01 0.00
3.00 0.11 0.00 0.00 55.00 3.31 2.01 0.00
4.00 0.16 0.00 0.00 56.00 3.31 2.01 0.00
5.00 0.21 0.00 0.00 57.00 3.31 2.01 0.00
6.00 0.26 0.00 0.00 58.00 3.31 2.01 0.00
7.00 0.33 0.00 0.00 59.00 3.31 2.01 0.00
8.00 0.40 0.01 0.02 60.00 3.31 2.01 0.00
9.00 0.49 0.02 0.05 61.00 3.31 2.01 0.00
10.00 0.60 0.05 0.09 62.00 3.31 2.01 0.00
11.00 0.78 0.12 0.22 63.00 3.31 2.01 0.00
12.00 2.19 1.06 7.07 64.00 3.31 2.01 0.00
13.00 2.56 1.36 0.42 ' 65.00 3.31 2.01 0.00
14.00 2.71 1.49 0.25 66.00 3.31 2.01 0.00
15.00 2.83 1.59 0.20 67.00 3.31 2.01 0.00
16.00 2.91 1.66 0.16 68.00 3.31 2.01 0.00
17.00 2.98 1.73 0.14 69.00 3.31 2.01 0.00
18.00 3.05 1.78 0.12 70.00 3.31 2.01 0.00
19.00 3.10 1.83 0.11 71.00 3.31 2.01 0.00
20.00 3.15 1.87 0.09 ' 72.00 3.31 2.01 0.00
21.00 3.19 1.91 0.09
22.00 3.23 1.94 0.08
23.00 3.27 1.98 0.08
24.00 3.31 2.01 0.08
25.00 3.31 2.01 0.00
26.00 3.31 2.01 0.00
27.00 3.31 2.01 0.00
28.00 3.31 2.01 0.00
29.00 3.31 2.01 0.00
30.00 3.31 2.01 0.00
31.00 3.31 2.01 0.00
32.00 3.31 2.01 0.00
33.00 3.31 2.01 0.00
34.00 3.31 2.01 0.00
35.00 3.31 2.01 0.00
36.00 3.31 2.01 0.00
37.00 3.31 2.01 0.00
38.00 3.31 2.01 0.00
39.00 3.31 2.01 0.00
40.00 3.31 2.01 0.00
41.00 3.31 2.01 0.00
42.00 3.31 2.01 0.00
43.00 3.31 2.01 0.00
44.00 3.31 2.01 0.00
45.00 3.31 2.01 0.00
46.00 3.31 2.01 0.00
47.00 3.31 2.01 0.00
48.00 3.31 2.01 0.00
49.00 3.31 2.01 0.00
50.00 3.31 2.01 0.00
51.00 3.31 2.01 0.00

2302-Pond 1 Type 1124-hr 2 Year-Spencer Rainfall=3.31"
Prepared by {enter your company name here} Page 16
HydroCAD®8.00 s/n 004317 ©2006 HydroCAD Software Solutions LLC 6/19/2023
Pond 3P: Wet Pond
Inflow Area = 2.300 ac, Inflow Depth = 2.01" for 2 Year-Spencer event
Inflow = 8.19 cfs @ 11.96 hrs, Volume= 0.386 af
Outflow = 3.16 cfs @ 12.07 hrs, Volume= 0.386 af, Atten= 61%, Lag= 6.9 min
Primary = 3.16 cfs @ 12.07 hrs, Volume= 0.386 af
Secondary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af
Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs
Peak Elev= 646.68' @ 12.07 hrs Surf.Area= 5,134 sf Storage= 6,097 cf
Plug-Flow detention time= 122.3 min calculated for 0.385 af (100% of inflow)
Center-of-Mass det. time= 123.4 min ( 936.9 - 813.4 )
Volume Invert Avail.Storage Storage Description
#1 644.50' 13,880 cf Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic-feet) (cubic-feet)
644.50 400 0 0
645.00 770 293 293
646.00 4,391 2,581 2,873
647.00 5,489 4,940 7,813
648.00 6,644 6,067 13,880
Device Routing Invert Outlet Devices
#1 Primary 641.75' 18.0" x 50.0' long Culvert Ke= 0.200
Outlet Invert= 641.25' S= 0.0100 '/' Cc= 0.900 n= 0.012
#2 Device 1 644.50' Special & User-Defined
Head (feet) 0.00 1.00 2.00 3.00 4.00 5.00 6.00
Disch. (cfs) 0.000 0.031 0.043 0.056 0.068 0.080 0.093
#3 Device 1 645.50' 12.0" Vert. Orifice/Grate C= 0.600
#4 Device 1 647.20' 16.0' long x 0.5' breadth Broad-Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00
Coef. (English) 2.80 2.92 3.08 3.30 3.32
#5 Secondary 647.50' 10.0' long x 12.0' 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) 2.57 2.62 2.70 2.67 2.66 2.67 2.66 2.64
Primary OutFlow Max=3.13 cfs @ 12.07 hrs HW=646.67' (Free Discharge)
L1=Culvert (Passes 3.13 cfs of 19.95 cfs potential flow)
2=Special & User-Defined (Custom Controls 0.05 cfs)
3=Orifice/Grate (Orifice Controls 3.08 cfs @ 3.93 fps)
4=Broad-Crested Rectangular Weir ( Controls 0.00 cfs)
Secondary OutFlow Max=0.00 cfs @ 0.00 hrs HW=644.50' (Free Discharge)
4-5=Broad-Crested Rectangular Weir ( Controls 0.00 cfs)

2302-Pond 1 Type 1124-hr 2 Year-Spencer Rainfall=3.31"
Prepared by {enter your company name here} Page 17
HydroCAD®8.00 s/n 004317 ©2006 HydroCAD Software Solutions LLC 6/19/2023
Hydrograph for Pond 3P: Wet Pond
Time Inflow Storage Elevation Outflow Primary Secondary
(hours) (cfs) (cubic-feet) (feet) (cfs) (cfs) (cfs)
0.00 0.00 0 644.50 0.00 0.00 0.00
2.50 0.00 0 644.50 0.00 0.00 0.00
5.00 0.00 0 644.50 0.00 0.00 0.00
7.50 0.01 17 644.54 0.00 0.00 0.00
10.00 0.09 325 645.04 0.02 0.02 0.00
12.50 0.66 3,867 646.22 1.79 1.79 0.00
15.00 0.20 1,775 645.72 0.23 0.23 0.00
17.50 0.13 1,581 645.66 0.14 0.14 0.00
20.00 0.09 1,479 645.62 0.10 0.10 0.00
22.50 0.08 1,421 645.60 0.08 0.08 0.00
25.00 0.00 1,224 645.54 0.04 0.04 0.00
27.50 0.00 945 645.42 0.03 0.03 0.00
30.00 0.00 703 645.31 0.03 0.03 0.00
32.50 0.00 494 645.18 0.02 0.02 0.00
35.00 0.00 324 645.04 0.02 0.02 0.00
37.50 0.00 198 644.87 0.01 0.01 0.00
40.00 0.00 115 644.74 0.01 0.01 0.00
42.50 0.00 63 644.64 0.00 0.00 0.00
45.00 0.00 34 644.58 0.00 0.00 0.00
47.50 0.00 17 644.54 0.00 0.00 0.00
50.00 0.00 9 644.52 0.00 0.00 0.00
52.50 0.00 5 644.51 0.00 0.00 0.00
55.00 0.00 2 644.51 0.00 0.00 0.00
57.50 0.00 1 644.50 0.00 0.00 0.00
60.00 0.00 1 644.50 0.00 0.00 0.00
62.50 0.00 0 644.50 0.00 0.00 0.00
65.00 0.00 0 644.50 0.00 0.00 0.00
67.50 0.00 0 644.50 0.00 0.00 0.00
70.00 0.00 0 644.50 0.00 0.00 0.00

2302-Pond 1 Type 1124-hr 2 Year-Spencer Rainfall=3.31"
Prepared by {enter your company name here} Page 18
HydroCAD®8.00 s/n 004317 ©2006 HydroCAD Software Solutions LLC 6/19/2023
Stage-Discharge for Pond 3P: Wet Pond
Elevation Discharge Primary Secondary Elevation Discharge Primary Secondary
(feet) (cfs) (cfs) (cfs) ' (feet) (cfs) (cfs) (cfs)
644.50 0.00 0.00 0.00 649.70 112.72 26.57 86.15
644.60 0.00 0.00 0.00 649.80 118.85 26.77 92.09
644.70 0.01 0.01 0.00 649.90 125.11 26.95 98.16
644.80 0.01 0.01 0.00 650.00 131.50 27.14 104.36
644.90 0.01 0.01 0.00 650.10 138.01 27.33 110.68
645.00 0.02 0.02 0.00 650.20 144.64 27.51 117.12
645.10 0.02 0.02 0.00 650.30 151.39 27.70 123.69
645.20 0.02 0.02 0.00 650.40 158.26 27.88 130.38
645.30 0.02 0.02 0.00 650.50 165.24 28.06 137.18
645.40 0.03 0.03 0.00
645.50 0.03 0.03 0.00
645.60 0.08 0.08 0.00
645.70 0.20 0.20 0.00
645.80 0.40 0.40 0.00
645.90 0.67 0.67 0.00
646.00 0.98 0.98 0.00
646.10 1.34 1.34 0.00
646.20 1.71 1.71 0.00
646.30 2.09 2.09 0.00
646.40 2.45 2.45 0.00
646.50 2.72 2.72 0.00
646.60 2.97 2.97 0.00
646.70 3.21 3.21 0.00
646.80 3.43 3.43 0.00
646.90 3.64 3.64 0.00
647.00 3.83 3.83 0.00
647.10 4.02 4.02 0.00
647.20 4.19 4.19 0.00
647.30 5.78 5.78 0.00
647.40 8.54 8.54 0.00
647.50 12.21 12.21 0.00
647.60 17.47 16.66 0.81
647.70 24.26 21.96 2.30
647.80 26.92 22.65 4.26
647.90 29.50 22.88 6.63
648.00 32.50 23.10 9.40
648.10 35.86 23.32 12.55
648.20 39.26 23.53 15.73
648.30 42.85 23.75 19.10
648.40 46.72 23.96 22.75
648.50 50.77 24.17 26.60
648.60 55.13 24.38 30.75
648.70 59.69 24.59 35.10
648.80 64.30 24.79 39.50
648.90 69.06 25.00 44.06
649.00 73.88 25.20 48.68
649.10 78.83 25.40 53.43
649.20 84.12 25.60 58.52
649.30 89.55 25.80 63.75
649.40 95.14 25.99 69.14
649.50 100.86 26.19 74.67
649.60 106.72 26.38 80.34

2302-Pond 1 Type 1124-hr 10 Year-Spencer Rainfall=4.81"
Prepared by {enter your company name here} Page 19
HydroCAD®8.00 s/n 004317 ©2006 HydroCAD Software Solutions LLC 6/19/2023
Time span=0.00-72.00 hrs, dt=0.05 hrs, 1441 points
Runoff by SCS TR-20 method, UH=SCS
Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method
Subcatchment 1S: Pre-developed Runoff Area=2.300 ac Runoff Depth=2.13"
Tc=12.8 min CN=73 Runoff=6.76 cfs 0.409 af
Subcatchment 2S: post-developed Runoff Area=2.300 ac Runoff Depth=3.39"
Tc=5.0 min CN=87 Runoff=13.45 cfs 0.649 af
Pond 3P: Wet Pond Peak Elev=647.33' Storage=9,672 cf Inflow=13.45 cfs 0.649 af
Primary=6.41 cfs 0.649 af Secondary=0.00 cfs 0.000 af Outflow=6.41 cfs 0.649 af
Total Runoff Area = 4.600 ac Runoff Volume= 1.058 of Average Runoff Depth = 2.76"
78.48% Pervious Area = 3.610 ac 21.52%Impervious Area = 0.990 ac

2302-Pond 1 Type 1124-hr 10 Year-Spencer Rainfall=4.81"
Prepared by {enter your company name here} Page 20
HydroCAD®8.00 s/n 004317 ©2006 HydroCAD Software Solutions LLC 6/19/2023
Subcatchment 1S: Pre-developed
Runoff = 6.76 cfs @ 12.05 hrs, Volume= 0.409 af, Depth= 2.13"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs
Type 1124-hr 10 Year-Spencer Rainfall=4.81"
Area (ac) CN Description
2.300 73 Woods, Fair, HSG C
2.300 Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
12.8 Direct Entry,

2302-Pond 1 Type 1124-hr 10 Year-Spencer Rainfall=4.81"
Prepared by {enter your company name here} Page 21
HydroCAD®8.00 s/n 004317 ©2006 HydroCAD Software Solutions LLC 6/19/2023
Hydrograph for Subcatchment 1S: Pre-developed
Time Precip. Excess Runoff Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs) (hours) (inches) (inches) (cfs)
0.00 0.00 0.00 0.00 52.00 4.81 2.13 0.00
1.00 0.05 0.00 0.00 53.00 4.81 2.13 0.00
2.00 0.11 0.00 0.00 54.00 4.81 2.13 0.00
3.00 0.17 0.00 0.00 55.00 4.81 2.13 0.00
4.00 0.23 0.00 0.00 56.00 4.81 2.13 0.00
5.00 0.30 0.00 0.00 57.00 4.81 2.13 0.00
6.00 0.38 0.00 0.00 58.00 4.81 2.13 0.00
7.00 0.48 0.00 0.00 59.00 4.81 2.13 0.00
8.00 0.58 0.00 0.00 60.00 4.81 2.13 0.00
9.00 0.71 0.00 0.00 61.00 4.81 2.13 0.00
10.00 0.87 0.00 0.02 62.00 4.81 2.13 0.00
11.00 1.13 0.04 0.11 63.00 4.81 2.13 0.00
12.00 3.19 0.98 6.02 64.00 4.81 2.13 0.00
13.00 3.71 1.33 0.55 65.00 4.81 2.13 0.00
14.00 3.94 1.49 0.32 66.00 4.81 2.13 0.00
15.00 4.11 1.60 0.25 67.00 4.81 2.13 0.00
16.00 4.23 1.70 0.20 68.00 4.81 2.13 0.00
17.00 4.34 1.77 0.17 69.00 4.81 2.13 0.00
18.00 4.43 1.84 0.15 70.00 4.81 2.13 0.00
19.00 4.51 1.90 0.13 71.00 4.81 2.13 0.00
20.00 4.58 1.96 0.11 72.00 4.81 2.13 0.00
21.00 4.64 2.00 0.11
22.00 4.70 2.05 0.10
23.00 4.76 2.09 0.10
24.00 4.81 2.13 0.10
25.00 4.81 2.13 0.00
26.00 4.81 2.13 0.00
27.00 4.81 2.13 0.00
28.00 4.81 2.13 0.00
29.00 4.81 2.13 0.00
30.00 4.81 2.13 0.00
31.00 4.81 2.13 0.00
32.00 4.81 2.13 0.00
33.00 4.81 2.13 0.00
34.00 4.81 2.13 0.00
35.00 4.81 2.13 0.00
36.00 4.81 2.13 0.00
37.00 4.81 2.13 0.00
38.00 4.81 2.13 0.00
39.00 4.81 2.13 0.00
40.00 4.81 2.13 0.00
41.00 4.81 2.13 0.00
42.00 4.81 2.13 0.00
43.00 4.81 2.13 0.00
44.00 4.81 2.13 0.00
45.00 4.81 2.13 0.00
46.00 4.81 2.13 0.00
47.00 4.81 2.13 0.00
48.00 4.81 2.13 0.00
49.00 4.81 2.13 0.00
50.00 4.81 2.13 0.00
51.00 4.81 2.13 0.00

2302-Pond 1 Type 1124-hr 10 Year-Spencer Rainfall=4.81"
Prepared by {enter your company name here} Page 22
HydroCAD®8.00 s/n 004317 ©2006 HydroCAD Software Solutions LLC 6/19/2023
Subcatchment 2S: post-developed
Runoff = 13.45 cfs @ 11.95 hrs, Volume= 0.649 af, Depth= 3.39"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs
Type 1124-hr 10 Year-Spencer Rainfall=4.81"
Area (ac) CN Description
1.310 79 50-75% Grass cover, Fair, HSG C
0.990 98 Bldg/Pave
2.300 87 Weighted Average
1.310 Pervious Area
0.990 Impervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry, post

2302-Pond 1 Type 1124-hr 10 Year-Spencer Rainfall=4.81"
Prepared by {enter your company name here} Page 23
HydroCAD®8.00 s/n 004317 ©2006 HydroCAD Software Solutions LLC 6/19/2023
Hydrograph for Subcatchment 2S: post-developed
Time Precip. Excess Runoff Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs) (hours) (inches) (inches) (cfs)
0.00 0.00 0.00 0.00 52.00 4.81 3.39 0.00
1.00 0.05 0.00 0.00 53.00 4.81 3.39 0.00
2.00 0.11 0.00 0.00 54.00 4.81 3.39 0.00
3.00 0.17 0.00 0.00 55.00 4.81 3.39 0.00
4.00 0.23 0.00 0.00 56.00 4.81 3.39 0.00
5.00 0.30 0.00 0.00 57.00 4.81 3.39 0.00
6.00 0.38 0.00 0.02 58.00 4.81 3.39 0.00
7.00 0.48 0.02 0.04 59.00 4.81 3.39 0.00
8.00 0.58 0.04 0.07 60.00 4.81 3.39 0.00
9.00 0.71 0.09 0.13 61.00 4.81 3.39 0.00
10.00 0.87 0.16 0.20 62.00 4.81 3.39 0.00
11.00 1.13 0.30 0.44 63.00 4.81 3.39 0.00
12.00 3.19 1.91 11.45 64.00 4.81 3.39 0.00
13.00 3.71 2.38 0.66 I 65.00 4.81 3.39 0.00
14.00 3.94 2.59 0.39 66.00 4.81 3.39 0.00
15.00 4.11 2.73 0.31 67.00 4.81 3.39 0.00
16.00 4.23 2.85 0.24 68.00 4.81 3.39 0.00
17.00 4.34 2.95 0.21 i 69.00 4.81 3.39 0.00
18.00 4.43 3.03 0.19 70.00 4.81 3.39 0.00
19.00 4.51 3.11 0.16 71.00 4.81 3.39 0.00
20.00 4.58 3.17 0.14 72.00 4.81 3.39 0.00
21.00 4.64 3.23 0.13
22.00 4.70 3.29 0.13
23.00 4.76 3.34 0.12
24.00 4.81 3.39 0.12
25.00 4.81 3.39 0.00
26.00 4.81 3.39 0.00
27.00 4.81 3.39 0.00
28.00 4.81 3.39 0.00
29.00 4.81 3.39 0.00
30.00 4.81 3.39 0.00
31.00 4.81 3.39 0.00
32.00 4.81 3.39 0.00
33.00 4.81 3.39 0.00
34.00 4.81 3.39 0.00
35.00 4.81 3.39 0.00
36.00 4.81 3.39 0.00
37.00 4.81 3.39 0.00
38.00 4.81 3.39 0.00
39.00 4.81 3.39 0.00
40.00 4.81 3.39 0.00
41.00 4.81 3.39 0.00
42.00 4.81 3.39 0.00
43.00 4.81 3.39 0.00
44.00 4.81 3.39 0.00
45.00 4.81 3.39 0.00
46.00 4.81 3.39 0.00
47.00 4.81 3.39 0.00
48.00 4.81 3.39 0.00
49.00 4.81 3.39 0.00
50.00 4.81 3.39 0.00
51.00 4.81 3.39 0.00

2302-Pond 1 Type 1124-hr 10 Year-Spencer Rainfall=4.81"
Prepared by (enter your company name here} Page 24
HydroCAD®8.00 s/n 004317 ©2006 HydroCAD Software Solutions LLC 6/19/2023
Pond 3P: Wet Pond
Inflow Area = 2.300 ac, Inflow Depth = 3.39" for 10 Year-Spencer event
Inflow = 13.45 cfs @ 11.95 hrs, Volume= 0.649 af
Outflow = 6.41 cfs @ 12.06 hrs, Volume= 0.649 af, Atten= 52%, Lag= 6.3 min
Primary = 6.41 cfs @ 12.06 hrs, Volume= 0.649 af
Secondary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af
Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs
Peak Elev= 647.33' @ 12.06 hrs Surf.Area= 5,867 sf Storage= 9,672 cf
Plug-Flow detention time= 90.8 min calculated for 0.649 af (100% of inflow)
Center-of-Mass det. time= 90.5 min ( 889.1 - 798.6 )
Volume Invert Avail.Storage Storage Description
#1 644.50' 13,880 cf Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic-feet) (cubic-feet)
644.50 400 0 0
645.00 770 293 293
646.00 4,391 2,581 2,873
647.00 5,489 4,940 7,813
648.00 6,644 6,067 13,880
Device Routing Invert Outlet Devices
#1 Primary 641.75' 18.0" x 50.0' long Culvert Ke= 0.200
Outlet Invert= 641.25' S= 0.0100 '/' Cc= 0.900 n= 0.012
#2 Device 1 644.50' Special & User-Defined
Head (feet) 0.00 1.00 2.00 3.00 4.00 5.00 6.00
Disch. (cfs) 0.000 0.031 0.043 0.056 0.068 0.080 0.093
#3 Device 1 645.50' 12.0" Vert. Orifice/Grate C= 0.600
#4 Device 1 647.20' 16.0' long x 0.5' breadth Broad-Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00
Coef. (English) 2.80 2.92 3.08 3.30 3.32
#5 Secondary 647.50' 10.0' long x 12.0' 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) 2.57 2.62 2.70 2.67 2.66 2.67 2.66 2.64
Primary OutFlow Max=6.17 cfs @ 12.06 hrs HW=647.32' (Free Discharge)
t 1=Culvert (Passes 6.17 cfs of 21.54 cfs potential flow)
I2=Special & User-Defined (Custom Controls 0.05 cfs)
3=Orifice/Grate (Orifice Controls 4.34 cfs @ 5.52 fps)
4=Broad-Crested Rectangular Weir (Weir Controls 1.78 cfs @ 0.96 fps)
Secondary OutFlow Max=0.00 cfs @ 0.00 hrs HW=644.50' (Free Discharge)
4-5=Broad-Crested Rectangular Weir ( Controls 0.00 cfs)

2302-Pond 1 Type 1124-hr 10 Year-Spencer Rainfall=4.81"
Prepared by {enter your company name here} Page 25
HydroCAD®8.00 s/n 004317 ©2006 HydroCAD Software Solutions LLC 6/19/2023
Hydrograph for Pond 3P: Wet Pond
Time Inflow Storage Elevation Outflow Primary Secondary
(hours) (cfs) (cubic-feet) (feet) (cfs) (cfs) (cfs)
0.00 0.00 0 644.50 0.00 0.00 0.00
2.50 0.00 0 644.50 0.00 0.00 0.00
5.00 0.00 0 644.50 0.00 0.00 0.00
7.50 0.06 196 644.87 0.01 0.01 0.00
10.00 0.20 1,040 645.46 0.03 0.03 0.00
12.50 1.05 6,136 646.68 3.17 3.17 0.00
15.00 0.31 1,987 645.78 0.36 0.36 0.00
17.50 0.20 1,740 645.71 0.22 0.22 0.00
20.00 0.14 1,606 645.66 0.15 0.15 0.00
22.50 0.12 1,546 645.65 0.13 0.13 0.00
25.00 0.00 1,281 645.56 0.05 0.05 0.00
27.50 0.00 982 645.44 0.03 0.03 0.00
30.00 0.00 735 645.33 0.03 0.03 0.00
32.50 0.00 522 645.20 0.02 0.02 0.00
35.00 0.00 346 645.06 0.02 0.02 0.00
37.50 0.00 213 644.89 0.01 0.01 0.00
40.00 0.00 124 644.75 0.01 0.01 0.00
42.50 0.00 69 644.65 0.00 0.00 0.00
45.00 0.00 37 644.58 0.00 0.00 0.00
47.50 0.00 19 644.55 0.00 0.00 0.00
50.00 0.00 10 644.52 0.00 0.00 0.00
52.50 0.00 5 644.51 0.00 0.00 0.00
55.00 0.00 3 644.51 0.00 0.00 0.00
57.50 0.00 1 644.50 0.00 0.00 0.00
60.00 0.00 1 644.50 0.00 0.00 0.00
62.50 0.00 0 644.50 0.00 0.00 0.00
65.00 0.00 0 644.50 0.00 0.00 0.00
67.50 0.00 0 644.50 0.00 0.00 0.00
70.00 0.00 0 644.50 0.00 0.00 0.00

2302-Pond 1 Type 1124-hr 10 Year-Spencer Rainfall=4.81"
Prepared by {enter your company name here} Page 26
HydroCAD®8.00 s/n 004317 ©2006 HydroCAD Software Solutions LLC 6/19/2023
Stage-Discharge for Pond 3P: Wet Pond
Elevation Discharge Primary Secondary Elevation Discharge Primary Secondary
(feet) (cfs) (cfs) (cfs) ' (feet) (cfs) (cfs) (cfs)
644.50 0.00 0.00 0.00 649.70 112.72 26.57 86.15
644.60 0.00 0.00 0.00 649.80 118.85 26.77 92.09
644.70 0.01 0.01 0.00 649.90 125.11 26.95 98.16
644.80 0.01 0.01 0.00 650.00 131.50 27.14 104.36
644.90 0.01 0.01 0.00 650.10 138.01 27.33 110.68
645.00 0.02 0.02 0.00 650.20 144.64 27.51 117.12
645.10 0.02 0.02 0.00 650.30 151.39 27.70 123.69
645.20 0.02 0.02 0.00 650.40 158.26 27.88 130.38
645.30 0.02 0.02 0.00 650.50 165.24 28.06 137.18
645.40 0.03 0.03 0.00
645.50 0.03 0.03 0.00
645.60 0.08 0.08 0.00
645.70 0.20 0.20 0.00
645.80 0.40 0.40 0.00
645.90 0.67 0.67 0.00
646.00 0.98 0.98 0.00
646.10 1.34 1.34 0.00
646.20 1.71 1.71 0.00
646.30 2.09 2.09 0.00
646.40 2.45 2.45 0.00
646.50 2.72 2.72 0.00
646.60 2.97 2.97 0.00
646.70 3.21 3.21 0.00
646.80 3.43 3.43 0.00
646.90 3.64 3.64 0.00
647.00 3.83 3.83 0.00
647.10 4.02 4.02 0.00
647.20 4.19 4.19 0.00
647.30 5.78 5.78 0.00
647.40 8.54 8.54 0.00
647.50 12.21 12.21 0.00
647.60 17.47 16.66 0.81
647.70 24.26 21.96 2.30
647.80 26.92 22.65 4.26
647.90 29.50 22.88 6.63
648.00 32.50 23.10 9.40
648.10 35.86 23.32 12.55
648.20 39.26 23.53 15.73
648.30 42.85 23.75 19.10
648.40 46.72 23.96 22.75
648.50 50.77 24.17 26.60
648.60 55.13 24.38 30.75
648.70 59.69 24.59 35.10
648.80 64.30 24.79 39.50
648.90 69.06 25.00 44.06
649.00 73.88 25.20 48.68
649.10 78.83 25.40 53.43
649.20 84.12 25.60 58.52
649.30 89.55 25.80 63.75
649.40 95.14 25.99 69.14
649.50 100.86 26.19 74.67
649.60 106.72 26.38 80.34

2302-Pond 1 Type 1124-hr 100 Year-Spencer Rainfall=7.14"
Prepared by {enter your company name here} Page 27
HydroCAD®8.00 s/n 004317 ©2006 HydroCAD Software Solutions LLC 6/19/2023
Time span=0.00-72.00 hrs, dt=0.05 hrs, 1441 points
Runoff by SCS TR-20 method, UH=SCS
Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method
Subcatchment 1S: Pre-developed Runoff Area=2.300 ac Runoff Depth=4.06"
Tc=12.8 min CN=73 Runoff=12.87 cfs 0.777 af
Subcatchment 2S: post-developed Runoff Area=2.300 ac Runoff Depth=5.61"
Tc=5.0 min CN=87 Runoff=21.60 cfs 1.076 af
Pond 3P: Wet Pond Peak Elev=647.63' Storage=11,511 cf Inflow=21.60 cfs 1.076 af
Primary=18.28 cfs 1.069 af Secondary=1.24 cfs 0.008 af Outflow=19.52 cfs 1.076 af
Total Runoff Area = 4.600 ac Runoff Volume= 1.854 af Average Runoff Depth =4.84"
78.48% Pervious Area = 3.610 ac 21.52%Impervious Area = 0.990 ac

2302-Pond 1 Type 1124-hr 100 Year-Spencer Rainfall=7.14"
Prepared by {enter your company name here} Page 28
HydroCAD®8.00 s/n 004317 ©2006 HydroCAD Software Solutions LLC 6/19/2023
Subcatchment 1 S: Pre-developed
Runoff = 12.87 cfs @ 12.05 hrs, Volume= 0.777 af, Depth= 4.06"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs
Type II 24-hr 100 Year-Spencer Rainfall=7.14"
Area (ac) CN Description
2.300 73 Woods, Fair, HSG C
2.300 Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
12.8 Direct Entry,

2302-Pond 1 Type 1124-hr 100 Year-Spencer Rainfall=7.14"
Prepared by {enter your company name here} Page 29
HydroCAD®8.00 s/n 004317 ©2006 HydroCAD Software Solutions LLC 6/19/2023
Hydrograph for Subcatchment 1S: Pre-developed
Time Precip. Excess Runoff Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs) (hours) (inches) (inches) (cfs)
0.00 0.00 0.00 0.00 52.00 7.14 4.06 0.00
1.00 0.07 0.00 0.00 53.00 7.14 4.06 0.00
2.00 0.16 0.00 0.00 54.00 7.14 4.06 0.00
3.00 0.25 0.00 0.00 55.00 7.14 4.06 0.00
4.00 0.34 0.00 0.00 56.00 7.14 4.06 0.00
5.00 0.45 0.00 0.00 57.00 7.14 4.06 0.00
6.00 0.57 0.00 0.00 58.00 7.14 4.06 0.00
7.00 0.71 0.00 0.00 59.00 7.14 4.06 0.00
8.00 0.86 0.00 0.02 60.00 7.14 4.06 0.00
9.00 1.05 0.02 0.06 61.00 7.14 4.06 0.00
10.00 1.29 0.07 0.14 62.00 7.14 4.06 0.00
11.00 1.68 0.19 0.36 63.00 7.14 4.06 0.00
12.00 4.73 2.07 11.73 64.00 7.14 4.06 0.00
13.00 5.51 2.69 0.95 ' 65.00 7.14 4.06 0.00
14.00 5.85 2.97 0.56 66.00 7.14 4.06 0.00
15.00 6.09 3.17 0.43 67.00 7.14 4.06 0.00
16.00 6.28 3.33 0.34 68.00 7.14 4.06 0.00
17.00 6.44 3.46 0.29 69.00 7.14 4.06 0.00
18.00 6.58 3.57 0.26 70.00 7.14 4.06 0.00
19.00 6.70 3.67 0.23 71.00 7.14 4.06 0.00
20.00 6.80 3.76 0.19 ' 72.00 7.14 4.06 0.00
21.00 6.89 3.84 0.18
22.00 6.98 3.91 0.17
23.00 7.06 3.99 0.17
24.00 7.14 4.06 0.16
25.00 7.14 4.06 0.00
26.00 7.14 4.06 0.00
27.00 7.14 4.06 0.00
28.00 7.14 4.06 0.00
29.00 7.14 4.06 0.00
30.00 7.14 4.06 0.00
31.00 7.14 4.06 0.00
32.00 7.14 4.06 0.00
33.00 7.14 4.06 0.00
34.00 7.14 4.06 0.00
35.00 7.14 4.06 0.00
36.00 7.14 4.06 0.00
37.00 7.14 4.06 0.00
38.00 7.14 4.06 0.00
39.00 7.14 4.06 0.00
40.00 7.14 4.06 0.00
41.00 7.14 4.06 0.00
42.00 7.14 4.06 0.00
43.00 7.14 4.06 0.00
44.00 7.14 4.06 0.00
45.00 7.14 4.06 0.00
46.00 7.14 4.06 0.00
47.00 7.14 4.06 0.00
48.00 7.14 4.06 0.00
49.00 7.14 4.06 0.00
50.00 7.14 4.06 0.00
51.00 7.14 4.06 0.00

2302-Pond 1 Type 1124-hr 100 Year-Spencer Rainfall=7.14"
Prepared by {enter your company name here} Page 30
HydroCAD®8.00 s/n 004317 ©2006 HydroCAD Software Solutions LLC 6/19/2023
Subcatchment 2S: post-developed
Runoff = 21.60 cfs @ 11.95 hrs, Volume= 1.076 af, Depth= 5.61"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs
Type II 24-hr 100 Year-Spencer Rainfall=7.14"
Area (ac) CN Description
1.310 79 50-75% Grass cover, Fair, HSG C
0.990 98 Bldg/Pave _
2.300 87 Weighted Average
1.310 Pervious Area
0.990 Impervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry, post

2302-Pond 1 Type 1124-hr 100 Year-Spencer Rainfall=7.14"
Prepared by {enter your company name here} Page 31
HydroCAD®8.00 s/n 004317 ©2006 HydroCAD Software Solutions LLC 6/19/2023
Hydrograph for Subcatchment 2S: post-developed
Time Precip. Excess Runoff Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs) (hours) (inches) (inches) (cfs)
0.00 0.00 0.00 0.00 52.00 7.14 5.61 0.00
1.00 0.07 0.00 0.00 53.00 7.14 5.61 0.00
2.00 0.16 0.00 0.00 54.00 7.14 5.61 0.00
3.00 0.25 0.00 0.00 55.00 7.14 5.61 0.00
4.00 0.34 0.00 0.01 56.00 7.14 5.61 0.00
5.00 0.45 0.01 0.04 57.00 7.14 5.61 0.00
6.00 0.57 0.04 0.08 58.00 7.14 5.61 0.00
7.00 0.71 0.09 0.12 59.00 7.14 5.61 0.00
8.00 0.86 0.15 0.17 60.00 7.14 5.61 0.00
9.00 1.05 0.25 0.28 61.00 7.14 5.61 0.00
10.00 1.29 0.40 0.41 62.00 7.14 5.61 0.00
11.00 1.68 0.66 0.82 63.00 7.14 5.61 0.00
12.00 4.73 3.32 18.22 64.00 7.14 5.61 0.00
13.00 5.51 4.05 1.02 65.00 7.14 5.61 0.00
14.00 5.85 4.38 0.61 66.00 7.14 5.61 0.00
15.00 6.09 4.61 0.48 67.00 7.14 5.61 0.00
16.00 6.28 4.79 0.37 68.00 7.14 5.61 0.00
17.00 6.44 4.94 0.33 69.00 7.14 5.61 0.00
18.00 6.58 5.07 0.29 70.00 7.14 5.61 0.00
19.00 6.70 5.19 0.25 71.00 7.14 5.61 0.00
20.00 6.80 5.28 0.21 ' 72.00 7.14 5.61 0.00
21.00 6.89 5.37 0.20
22.00 6.98 5.46 0.19
23.00 7.06 5.54 0.18
24.00 7.14 5.61 0.18
25.00 7.14 5.61 0.00
26.00 7.14 5.61 0.00
27.00 7.14 5.61 0.00
28.00 7.14 5.61 0.00
29.00 7.14 5.61 0.00
30.00 7.14 5.61 0.00
31.00 7.14 5.61 0.00
32.00 7.14 5.61 0.00
33.00 7.14 5.61 0.00
34.00 7.14 5.61 0.00
35.00 7.14 5.61 0.00
36.00 7.14 5.61 0.00
37.00 7.14 5.61 0.00
38.00 7.14 5.61 0.00
39.00 7.14 5.61 0.00
40.00 7.14 5.61 0.00
41.00 7.14 5.61 0.00
42.00 7.14 5.61 0.00
43.00 7.14 5.61 0.00
44.00 7.14 5.61 0.00
45.00 7.14 5.61 0.00
46.00 7.14 5.61 0.00
47.00 7.14 5.61 0.00
48.00 7.14 5.61 0.00
49.00 7.14 5.61 0.00
50.00 7.14 5.61 0.00
51.00 7.14 5.61 0.00

2302-Pond 1 Type 1124-hr 100 Year-Spencer Rainfall=7.14"
Prepared by {enter your company name here} Page 32
HydroCAD®8.00 s/n 004317 ©2006 HydroCAD Software Solutions LLC 6/19/2023
Pond 3P: Wet Pond
Inflow Area = 2.300 ac, Inflow Depth = 5.61" for 100 Year-Spencer event
Inflow = 21.60 cfs @ 11.95 hrs, Volume= 1.076 af
Outflow = 19.52 cfs @ 12.00 hrs, Volume= 1.076 af, Atten= 10%, Lag= 2.9 min
Primary = 18.28 cfs @ 12.00 hrs, Volume= 1.069 af
Secondary = 1.24 cfs @ 12.00 hrs, Volume= 0.008 af
Routing by Stor-Ind method, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs
Peak Elev= 647.63' @ 12.00 hrs Surf.Area= 6,219 sf Storage= 11,511 cf
Plug-Flow detention time= 66.2 min calculated for 1.076 af (100% of inflow)
Center-of-Mass det. time= 65.9 min ( 850.4 - 784.5 )
Volume _ Invert Avail.Storage Storage Description _
#1 644.50' 13,880 cf Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic-feet) (cubic-feet)
644.50 400 0 0
645.00 770 293 293
646.00 4,391 2,581 2,873
647.00 5,489 4,940 7,813
648.00 6,644 6,067 13,880
Device Routing Invert Outlet Devices
#1 Primary 641.75' 18.0" x 50.0' long Culvert Ke= 0.200
Outlet Invert= 641.25' S= 0.0100 '/' Cc= 0.900 n= 0.012
#2 Device 1 644.50' Special & User-Defined
Head (feet) 0.00 1.00 2.00 3.00 4.00 5.00 6.00
Disch. (cfs) 0.000 0.031 0.043 0.056 0.068 0.080 0.093
#3 Device 1 645.50' 12.0" Vert. Orifice/Grate C= 0.600
#4 Device 1 647.20' 16.0' long x 0.5' breadth Broad-Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00
Coef. (English) 2.80 2.92 3.08 3.30 3.32
#5 Secondary 647.50' 10.0' long x 12.0' 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) 2.57 2.62 2.70 2.67 2.66 2.67 2.66 2.64
Primary OutFlow Max=18.21 cfs @ 12.00 hrs HW=647.63' (Free Discharge)
L1=Culvert (Passes 18.21 cfs of 22.27 cfs potential flow)
2=Special & User-Defined (Custom Controls 0.06 cfs)
3=Orifice/Grate (Orifice Controls 4.83 cfs @ 6.15 fps)
4=Broad-Crested Rectangular Weir (Weir Controls 13.33 cfs @ 1.93 fps)
Secondary OutFlow Max=1.22 cfs @ 12.00 hrs HW=647.63' (Free Discharge)
4-5=Broad-Crested Rectangular Weir (Weir Controls 1.22 cfs @ 0.93 fps)

2302-Pond 1 Type 1124-hr 100 Year-Spencer Rainfall=7.14"
Prepared by {enter your company name here} Page 33
HydroCAD®8.00 s/n 004317 ©2006 HydroCAD Software Solutions LLC 6/19/2023
Hydrograph for Pond 3P: Wet Pond
Time Inflow Storage Elevation Outflow Primary Secondary
(hours) (cfs) (cubic-feet) (feet) (cfs) (cfs) (cfs)
0.00 0.00 0 644.50 0.00 0.00 0.00
2.50 0.00 0 644.50 0.00 0.00 0.00
5.00 0.04 93 644.70 0.01 0.01 0.00
7.50 0.15 777 645.35 0.03 0.03 0.00
10.00 0.41 1,923 645.76 0.32 0.32 0.00
12.50 1.64 7,179 646.88 3.60 3.60 0.00
15.00 0.48 2,270 645.85 0.54 0.54 0.00
17.50 0.31 1,944 645.77 0.33 0.33 0.00
20.00 0.21 1,768 645.71 0.23 0.23 0.00
22.50 0.19 1,696 645.69 0.19 0.19 0.00
25.00 0.00 1,332 645.57 0.06 0.06 0.00
27.50 0.00 1,010 645.45 0.03 0.03 0.00
30.00 0.00 760 645.34 0.03 0.03 0.00
32.50 0.00 543 645.22 0.02 0.02 0.00
35.00 0.00 362 645.08 0.02 0.02 0.00
37.50 0.00 225 644.91 0.01 0.01 0.00
40.00 0.00 132 644.76 0.01 0.01 0.00
42.50 0.00 74 644.66 0.00 0.00 0.00
45.00 0.00 39 644.59 0.00 0.00 0.00
47.50 0.00 21 644.55 0.00 0.00 0.00
50.00 0.00 11 644.53 0.00 0.00 0.00
52.50 0.00 5 644.51 0.00 0.00 0.00
55.00 0.00 3 644.51 0.00 0.00 0.00
57.50 0.00 1 644.50 0.00 0.00 0.00
60.00 0.00 1 644.50 0.00 0.00 0.00
62.50 0.00 0 644.50 0.00 0.00 0.00
65.00 0.00 0 644.50 0.00 0.00 0.00
67.50 0.00 0 644.50 0.00 0.00 0.00
70.00 0.00 0 644.50 0.00 0.00 0.00

2302-Pond 1 Type 1124-hr 100 Year-Spencer Rainfall=7.14"
Prepared by {enter your company name here} Page 34
HydroCAD®8.00 s/n 004317 ©2006 HydroCAD Software Solutions LLC 6/19/2023
Stage-Discharge for Pond 3P: Wet Pond
Elevation Discharge Primary Secondary Elevation Discharge Primary Secondary
(feet) (cfs) (cfs) (cfs) ' (feet) (cfs) (cfs) (cfs)
644.50 0.00 0.00 0.00 649.70 112.72 26.57 86.15
644.60 0.00 0.00 0.00 649.80 118.85 26.77 92.09
644.70 0.01 0.01 0.00 649.90 125.11 26.95 98.16
644.80 0.01 0.01 0.00 650.00 131.50 27.14 104.36
644.90 0.01 0.01 0.00 650.10 138.01 27.33 110.68
645.00 0.02 0.02 0.00 650.20 144.64 27.51 117.12
645.10 0.02 0.02 0.00 650.30 151.39 27.70 123.69
645.20 0.02 0.02 0.00 650.40 158.26 27.88 130.38
645.30 0.02 0.02 0.00 650.50 165.24 28.06 137.18
645.40 0.03 0.03 0.00
645.50 0.03 0.03 0.00
645.60 0.08 0.08 0.00
645.70 0.20 0.20 0.00
645.80 0.40 0.40 0.00
645.90 0.67 0.67 0.00
646.00 0.98 0.98 0.00
646.10 1.34 1.34 0.00
646.20 1.71 1.71 0.00
646.30 2.09 2.09 0.00
646.40 2.45 2.45 0.00
646.50 2.72 2.72 0.00
646.60 2.97 2.97 0.00
646.70 3.21 3.21 0.00
646.80 3.43 3.43 0.00
646.90 3.64 3.64 0.00
647.00 3.83 3.83 0.00
647.10 4.02 4.02 0.00
647.20 4.19 4.19 0.00
647.30 5.78 5.78 0.00
647.40 8.54 8.54 0.00
647.50 12.21 12.21 0.00
647.60 17.47 16.66 0.81
647.70 24.26 21.96 2.30
647.80 26.92 22.65 4.26
647.90 29.50 22.88 6.63
648.00 32.50 23.10 9.40
648.10 35.86 23.32 12.55
648.20 39.26 23.53 15.73
648.30 42.85 23.75 19.10
648.40 46.72 23.96 22.75
648.50 50.77 24.17 26.60
648.60 55.13 24.38 30.75
648.70 59.69 24.59 35.10
648.80 64.30 24.79 39.50
648.90 69.06 25.00 44.06
649.00 73.88 25.20 48.68
649.10 78.83 25.40 53.43
649.20 84.12 25.60 58.52
649.30 89.55 25.80 63.75
649.40 95.14 25.99 69.14
649.50 100.86 26.19 74.67
649.60 106.72 26.38 80.34