SW3190701_Engineering Calculations (Sand Filter)_20190708

POST CONSTRUCTION SAND FILTER CALCULATIONS
FOR
HARWOOD AUTOMOTIVE
Midland, NC
LATHAM-WALTERS ENGINEERING, INC.
16507-A NORTHCROSS DRIVE
HUNTERSVILLE, N.C. 28078
Phone:[phone] Fax:[phone]
N.C. Corporate License C-1815
FOR
Harwood Automotive
3130 Hwy. 24-27
Midland, NC 28107
DATE: June 5, 2019
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STORMWATER MANAGEMENT SUMMARY
Harwood Automotive, Inc. is located on a 4.94 acre site in Midland, NC. The owner plans to
construct a 3990 sf addition to the facility. Additional pavement will be constructed around the
proposed facility. After construction, the site will have approximately 1.12 acres of built upon
area. This includes approximately 0.72 acres of existing impervious and 0.40 acres of new
impervious. Upon completion, the site will only be 22.80 percent impervious which would
normally be considered a low density project. However, the Town of Midland has performance
standards for low density projects based upon a points system. If a low density development
cannot meet these performance standards, then an approved stormwater control measure or
structure shall be provided, in compliance with the Town of Midland's stormwater guidelines
for water quality and flood control.
For this project, we were unable to meet the performance standards, so a sand filter will be
constructed. This sand filter will treat all of the new impervious areas. However, an existing
gravel parking area will be replaced with a paved parking area. This area does not drain to the
sand filter, but due to the size (0.07 acres) and current use (gravel parking), the buffer/planting
area around the parking will be sufficient for the area.
The sand filter is located southwest of the building expansion. The drainage area to the basin
is 27.12 percent impervious based upon a drainage area of 1.18 acres and 0.32 acres of built
upon impervious area. The sand filter releases the first inch of rainfall in 1.66 days (40 hours)
The system also provides stormwater detention for the 2, 10, and 25 year storms. The
maximum ponding depth for the 25 year storm is 1.89'.
The owners have provided a signed operation and maintenance plan for the sand filter. As
outlined in the document, the sand filter will require continued monitoring and maintenance to
ensure that it functions as intended.

TR 55 Urban Hydrology for Small Watershed; LATHAM-WALTERS ENGINEERING, INC.
Time of Concentration & Travel Time 16507-A Northcross Drive
Harwood Automotive Huntersville, NC 28078
Midland, 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)
3.52
P2
2 Year - 24 Hour Rainfall for Midland, NC
1.50%
s
Slope of hydraulic grade line
0.254
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
427
Length of Unpaved Flow
1.99%
Slope of Paved Flow
1.99%
Slope of Unpaved Flow
2.276
V2 -Unpaved (fps)
2.868
V2 - Paved (fps)
0.000
T2 Paved (seconds)
187.576
T2 Unpaved (seconds)
0.052
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
0.307 Tc = T1 + T2 + T3 + T4 (hrs.)
18.39 Total Tc (minutes)
Pre Developed Tc = 18.39 minutes

TR 55 Urban Hydrology for Small Watersheds LATHAM-WALTERS ENGINEERING, INC.
Time of Concentration & Travel Time 16507-A Northcross Drive
Harwood Automotive Huntersville, NC 28078
Midland, NC [phone]
Post -developed
Tc for Existing Drainage Area-Basin#1
Tc = T1 + T2 + T3 Time of Concentration
1. Sheet Flow:
T1 = (0.007 x (nQA0.8))/((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)
3.52 P2 2 Year - 24 Hour Rainfall for Midland, NC
1.50% s Slope of hydraulic grade line
0.254 T1 Travel Time (hr.)
2. Shallow Concentrated Flow
V2 = (16.1345's^0.5) Unpaved
V2 = (20.3282's^0.5) Paved
0.01
Length of Paved Flow
296
Length of Unpaved Flow
3.07%
Slope of Paved Flow
3.07%
Slope of Unpaved Flow
2.829
V2 - Unpaved (fps)
3.564
V2 - Paved (fps)
0.003
T2 Paved (seconds)
104.631
T2 Unpaved (seconds)
0.029
T2 Total (hours)
5. Open Channel Flow
V = (1.49 x (r)^0.67 x (s)^0.5)/n Velocity from Manning's Equation (fps)
1.5 a - area of foot depth ditch with 1:1 side slopes. ft^2
0.65 r - hydraulic radius, ft ; Area/Wetted Perimeter
0.01 s - slope of hydraulic grade line, (ft/ft)
0.03 n - Manning's roughness coefficient
3.727 V - velocity in fps
140 Length of Flow (ft.)
0.010 T3 (hrs.) Length/Velocity/3600
0.294 Tc = T1 + T2 + T3 (hrs.)
17.64 Total Tc (minutes)
Post Developed Tc = 17.64 minutes

Harwood Automotive
Basin #1
Midland, NC
Weighted Curve Number Calculations
Latham -Walters Engineering, Inc.
16507-A Northcross Drive
Huntersville, NC 28078
Pre -Developed Soil Types C KkB 1.18 Ac.
1.18 Acres Total
Post Developed Soils Type
Hydrologic Soils Group:
C
KkB
1.18 Ac.
Ac.
1.18 Acres Total
Pre -Developed:
Drainage Area Cn
Product
Description
1.08 Ac.
73
79.07998
Wooded
C Soil
0.10
98
9.8
Paved
1.18 Total
88.87998
Sum
Composite Cn
75.1
Pre -Developed
Post -Developed:
Basin 2S
Drainage Area Cn
Product
Description
0.32 Ac.
98
31.36
Impervious Area
0.25 Ac.
73
18.39412
Wooded
0.61 Ac.
79
48.19
Open Space
1.18
97.94412
Sum
Composite Cn
82.9
Post -Developed
C Soils
C Soils
C Soils

Harwood Automotive Latham -Walters Engineering, Inc.
16507-A Northcross Drive
Harrisburg, 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 = sf
df = filter bed depth, ft. = ft.
k = coefficient of permeability of filter media (ft/day) = ft/day
h = average height of water above filter bed (ft) 1,2, etc.
h
Q
cf/day
Q
cfs
1
1065.732
0.012
2
1492.025
0.017
3
1918.318
0.022
4
2344.61
0.027
5
2770.903
0.032
6
3197.196
0.037
7
3623.489
0.042
8
4049.782
0.047
9
4476.075
0.052
10
4902.367
0.057

Harwood Automotive, Midland, NC
Sand Filter Calculation - NCDEQ Design Manual
Basin# 1
1. Calculate Runoff Coeff, (Rv)
Drainage area to filter, Ad = 1.18 ac
Impervious area to filter forebay= 0.32 ac.
Impervious percentage = 27.12% to basin
Rv = 0.05 + 0.9(%Imp) = 0.2940678
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 =
1260 cf (used to size Af)
WQVADJ=
945 cf
WQV=
0.0217 ac-ft.
Storage:
Area
Vol.
Cum Vol
526
1233
0
0
527
2125
1679
1679
528
3432
2778.5
4457.5
529
5368
4400
8857.5
Calculate Depth for WQ Volume:
526 0
526.56 945
527 1679
Elevation of WQ Volume = 526.56 (hA for the 1 inch storm)
3. Calculate the minimum surface area for the Sand Filter & Sediment Chamber
Area of chambers
As (ft): 0.066 x WQV(ft2) = 83 sf 750 sf Area of Forebay
Af (ft): [WQV x dF1 / [(k)(t)(hA+d0l = 183 sf 483 sf Total Area of Filter
hMaxFilter(ft): 0.56
dF 1.5 ft h0t): 0.28
hA 0.28 ft/day
k 3.5 ft/day
t 1.66 days

4. Water Quality Peak Flow (WQp) from HydroCad: 0.08 cfs from HydroCad 1 "-24 Hour Storm
5. Underdrain Calculations:
Q: Flow Rate through Soil Media with a Safety Factor of 10: 0.17269
D = 16[(Q x n)/(So.5)](318) 4.12153
n 0.011
S 0.5%
55 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%
44 l.f. of pipe
44 l.f. x 4 rows/ft x 4 holes/ft = 528 holes
50% of perforations = 264 holes
Capacity of one hole = 0.0083 cfs based upon CA(2gh)^0.5
Total Capacity = 2.1912 cfs which is 98.7 times the capacity of the sand filter.
Total Capacityof 6" PVC Lia 0.50% is 2.7 cfs (1.35 cfs assuming 50% clogged) from Mannings and BMP Manual.

(Predeveloped)
(2S � 3P
(Post Developed)
Subcat Reach on Link
(Sand Filter 1)

Pond 1
Prepared by {enter your company name here} Page 2
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Area Listing (all nodes)
Area (acres) CN Description (subcats)
1.180 75 See Calculations (1 S)
1.180 83 (2S)
2.360

Pond 1 Type 11 24-hr 1 " - Charlotte Rainfall= 1. 00 "
Prepared by (enter your company name here) Page 3
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Time span =0.00-200.00 hrs, dt=0.10 hrs, 2001 points
Runoff by SCS TR-20 method, UH=SCS
Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method
Subcatchment 1S: (Predeveloped)
Subcatchment 2S: (Post Developed)
Pond 3P: (Sand Filter 1)
Runoff Area=1.180 ac Runoff Depth=0.03"
Tc=18.4 min CN=75 Runoff=0.00 cfs 0.003 of
Runoff Area=1.180 ac Runoff Depth=0.13"
Tc=17.6 min CN=83 Runoff=0.11 cfs 0.013 of
Peak Elev=526.31' Storage=420 cf Inflow=0.11 cfs 0.013 of
Outflow=0.00 cfs 0.013 of
Total Runoff Area = 2.360 ac Runoff Volume = 0.016 of Average Runoff Depth = 0.08"
100.00% Pervious Area = 2.360 ac 0.00% Impervious Area = 0.000 ac

Pond
Type 1124-hr 1 " - Charlotte Rainfall=1. 00"
Prepared by {enter your company name here} Page 4
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Subcatchment 1 S: (Predeveloped)
Runoff = 0.00 cfs @ 13.11 hrs, Volume= 0.003 af, Depth= 0.03"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-200.00 hrs, dt= 0.10 hrs
Type II 24-hr 1" - Charlotte Rainfall=1.00"
Area (ac) CN Description
1.180 75 See Calculations
1.180 Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
18.4 Direct Entry,
Subcatchment 1 S: (Predeveloped)
Hydrograph
0.005
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---'---1---
0.005
0.00
cfs --7---1i---r---li---r--�---r--�---Ir--7---1i---r---li---Ir--�---Ir--�---
-Runoff
0.004
0.004
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0.004
0.004
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0.004
--+
-+--+---+--+--+---+--+---+--+---+--+--+---+---I---+--+---I---+---
1
1
1- Runoff Area-1.1-80-ac
0.003
--
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0.003
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0.003
--,
-
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f VGIume=O.-003'af--
0.003
--
-- --
------+------+--
---
--
---'---
---i[' noff Depth=0-03 r-
0 0.002
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+
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0.002
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0.002
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0.001
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0.001
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0.001
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0.000
--
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0
0 10
20
30
40 50 60
70
80
90
100
110 120 130 140 150 160 170 180 190 200
Time (hours)

Pond
Type 1124-hr 1 " - Charlotte Rainfall=1. 00"
Prepared by (enter your company name here) Page 5
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Hydrograph for Subcatchment 1S: (Predeveloped)
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
0.00
0.00
0.00
0.00
2.00
0.02
0.00
0.00
4.00
0.05
0.00
0.00
6.00
0.08
0.00
0.00
8.00
0.12
0.00
0.00
10.00
0.18
0.00
0.00
12.00
0.66
0.00
0.00
14.00
0.82
0.01
0.00
16.00
0.88
0.01
0.00
18.00
0.92
0.02
0.00
20.00
0.95
0.02
0.00
22.00
0.98
0.03
0.00
24.00
1.00
0.03
0.00
26.00
1.00
0.03
0.00
28.00
1.00
0.03
0.00
30.00
1.00
0.03
0.00
32.00
1.00
0.03
0.00
34.00
1.00
0.03
0.00
36.00
1.00
0.03
0.00
38.00
1.00
0.03
0.00
40.00
1.00
0.03
0.00
42.00
1.00
0.03
0.00
44.00
1.00
0.03
0.00
46.00
1.00
0.03
0.00
48.00
1.00
0.03
0.00
50.00
1.00
0.03
0.00
52.00
1.00
0.03
0.00
54.00
1.00
0.03
0.00
56.00
1.00
0.03
0.00
58.00
1.00
0.03
0.00
60.00
1.00
0.03
0.00
62.00
1.00
0.03
0.00
64.00
1.00
0.03
0.00
66.00
1.00
0.03
0.00
68.00
1.00
0.03
0.00
70.00
1.00
0.03
0.00
72.00
1.00
0.03
0.00
74.00
1.00
0.03
0.00
76.00
1.00
0.03
0.00
78.00
1.00
0.03
0.00
80.00
1.00
0.03
0.00
82.00
1.00
0.03
0.00
84.00
1.00
0.03
0.00
86.00
1.00
0.03
0.00
88.00
1.00
0.03
0.00
90.00
1.00
0.03
0.00
92.00
1.00
0.03
0.00
94.00
1.00
0.03
0.00
96.00
1.00
0.03
0.00
98.00
1.00
0.03
0.00
100.00
1.00
0.03
0.00
102.00
1.00
0.03
0.00
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
104.00
1.00
0.03
0.00
106.00
1.00
0.03
0.00
108.00
1.00
0.03
0.00
110.00
1.00
0.03
0.00
112.00
1.00
0.03
0.00
114.00
1.00
0.03
0.00
116.00
1.00
0.03
0.00
118.00
1.00
0.03
0.00
120.00
1.00
0.03
0.00
122.00
1.00
0.03
0.00
124.00
1.00
0.03
0.00
126.00
1.00
0.03
0.00
128.00
1.00
0.03
0.00
130.00
1.00
0.03
0.00
132.00
1.00
0.03
0.00
134.00
1.00
0.03
0.00
136.00
1.00
0.03
0.00
138.00
1.00
0.03
0.00
140.00
1.00
0.03
0.00
142.00
1.00
0.03
0.00
144.00
1.00
0.03
0.00
146.00
1.00
0.03
0.00
148.00
1.00
0.03
0.00
150.00
1.00
0.03
0.00
152.00
1.00
0.03
0.00
154.00
1.00
0.03
0.00
156.00
1.00
0.03
0.00
158.00
1.00
0.03
0.00
160.00
1.00
0.03
0.00
162.00
1.00
0.03
0.00
164.00
1.00
0.03
0.00
166.00
1.00
0.03
0.00
168.00
1.00
0.03
0.00
170.00
1.00
0.03
0.00
172.00
1.00
0.03
0.00
174.00
1.00
0.03
0.00
176.00
1.00
0.03
0.00
178.00
1.00
0.03
0.00
180.00
1.00
0.03
0.00
182.00
1.00
0.03
0.00
184.00
1.00
0.03
0.00
186.00
1.00
0.03
0.00
188.00
1.00
0.03
0.00
190.00
1.00
0.03
0.00
192.00
1.00
0.03
0.00
194.00
1.00
0.03
0.00
196.00
1.00
0.03
0.00
198.00
1.00
0.03
0.00
200.00
1.00
0.03
0.00

Pond
Type 1124-hr 1 " - Charlotte Rainfall=1. 00"
Prepared by {enter your company name here} Page 6
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Subcatchment 2S: (Post Developed)
Runoff = 0.11 cfs @ 12.16 hrs, Volume= 0.013 af, Depth= 0.13"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-200.00 hrs, dt= 0.10 hrs
Type II 24-hr 1" - Charlotte Rainfall=1.00"
Area (ac) CN Description
1.180 83
1.180 Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
17.6 Direct Entry,
Subcatchment 2S: (Post Developed)
Hydrograph
0.125
--
------
---
-
-
------ --
- - -- ------
0.12
0.115
cfs --
--------------I_
--
-r --
---r--Y---r--Y------Y------+----
--r------r------r--
0.11
---i
0.11
0.105
--
--i --
---
--
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--T-----Typ,It-24�hr-r�11-�
C iaKtotte-
0.1
--L
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L--- '---
1--- '--- L------L----j--+--- '--- L�--
li
0.095
--
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- t-
-- r-
- t
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--- --- t---li--- RaInfalha.0©11-
0.09
0.085
---
--+
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--
---II--- ---li
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+--- I -Runoff Ar"=1-1-8A Ac-
0.08
0.075
I
- -L
l
l
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- �_-_-_-I_-_--
Y_-_-_-I_-_-_-
Y_---I_-_-_-
Y_---I--- ,11��urIof n0Iptli-_0,a0.065
---
0 0.06
IL0.055
--+
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--li --
---li
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--- -II ----- ----'i-fjr�—�i�.i�i- �n--
0.05
--L
--'---
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---1---1---'---L---'---L---'---L------L---'---L-/�--''---L--
li---t
li---tli---r---li---tCN=83
0.045
--t
-----t---r--t---Ir--t---Ir--t
---
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0.04
---'
--'---
---'---
---I_
0.035
--+
-----+---+--+------+------+------+--+---+--+---+------+------+--
0.03
---
--li-----1
i-----I-
0.025
--L
--'--
-L-
--L--L---1---1---'---L---'---L------L------L------L------L--
0.02
---Y---r--Y------Y---r--Y------Y------r------r------r------r--
0.015
---'
-'---
---'---
---I_
0.01
--+
-+--+---+--+---+--+---I---+---I---+---I---+---I---+---I---+---I---+--
0.005
---
--
- ------
------ ---I-
0
0 10 20
30
40
50
60 70
80 90 100
110 120 130 140 150 160 170 180 190 200
Time (hours)
— Runoff

Pond
Type 1124-hr 1 " - Charlotte Rainfall=1. 00"
Prepared by (enter your company name here) Page 7
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Hydrograph for Subcatchment 2S: (Post Developed)
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
0.00
0.00
0.00
0.00
2.00
0.02
0.00
0.00
4.00
0.05
0.00
0.00
6.00
0.08
0.00
0.00
8.00
0.12
0.00
0.00
10.00
0.18
0.00
0.00
12.00
0.66
0.03
0.04
14.00
0.82
0.07
0.02
16.00
0.88
0.09
0.01
18.00
0.92
0.10
0.01
20.00
0.95
0.11
0.01
22.00
0.98
0.12
0.01
24.00
1.00
0.13
0.01
26.00
1.00
0.13
0.00
28.00
1.00
0.13
0.00
30.00
1.00
0.13
0.00
32.00
1.00
0.13
0.00
34.00
1.00
0.13
0.00
36.00
1.00
0.13
0.00
38.00
1.00
0.13
0.00
40.00
1.00
0.13
0.00
42.00
1.00
0.13
0.00
44.00
1.00
0.13
0.00
46.00
1.00
0.13
0.00
48.00
1.00
0.13
0.00
50.00
1.00
0.13
0.00
52.00
1.00
0.13
0.00
54.00
1.00
0.13
0.00
56.00
1.00
0.13
0.00
58.00
1.00
0.13
0.00
60.00
1.00
0.13
0.00
62.00
1.00
0.13
0.00
64.00
1.00
0.13
0.00
66.00
1.00
0.13
0.00
68.00
1.00
0.13
0.00
70.00
1.00
0.13
0.00
72.00
1.00
0.13
0.00
74.00
1.00
0.13
0.00
76.00
1.00
0.13
0.00
78.00
1.00
0.13
0.00
80.00
1.00
0.13
0.00
82.00
1.00
0.13
0.00
84.00
1.00
0.13
0.00
86.00
1.00
0.13
0.00
88.00
1.00
0.13
0.00
90.00
1.00
0.13
0.00
92.00
1.00
0.13
0.00
94.00
1.00
0.13
0.00
96.00
1.00
0.13
0.00
98.00
1.00
0.13
0.00
100.00
1.00
0.13
0.00
102.00
1.00
0.13
0.00
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
104.00
1.00
0.13
0.00
106.00
1.00
0.13
0.00
108.00
1.00
0.13
0.00
110.00
1.00
0.13
0.00
112.00
1.00
0.13
0.00
114.00
1.00
0.13
0.00
116.00
1.00
0.13
0.00
118.00
1.00
0.13
0.00
120.00
1.00
0.13
0.00
122.00
1.00
0.13
0.00
124.00
1.00
0.13
0.00
126.00
1.00
0.13
0.00
128.00
1.00
0.13
0.00
130.00
1.00
0.13
0.00
132.00
1.00
0.13
0.00
134.00
1.00
0.13
0.00
136.00
1.00
0.13
0.00
138.00
1.00
0.13
0.00
140.00
1.00
0.13
0.00
142.00
1.00
0.13
0.00
144.00
1.00
0.13
0.00
146.00
1.00
0.13
0.00
148.00
1.00
0.13
0.00
150.00
1.00
0.13
0.00
152.00
1.00
0.13
0.00
154.00
1.00
0.13
0.00
156.00
1.00
0.13
0.00
158.00
1.00
0.13
0.00
160.00
1.00
0.13
0.00
162.00
1.00
0.13
0.00
164.00
1.00
0.13
0.00
166.00
1.00
0.13
0.00
168.00
1.00
0.13
0.00
170.00
1.00
0.13
0.00
172.00
1.00
0.13
0.00
174.00
1.00
0.13
0.00
176.00
1.00
0.13
0.00
178.00
1.00
0.13
0.00
180.00
1.00
0.13
0.00
182.00
1.00
0.13
0.00
184.00
1.00
0.13
0.00
186.00
1.00
0.13
0.00
188.00
1.00
0.13
0.00
190.00
1.00
0.13
0.00
192.00
1.00
0.13
0.00
194.00
1.00
0.13
0.00
196.00
1.00
0.13
0.00
198.00
1.00
0.13
0.00
200.00
1.00
0.13
0.00

Pond
Type 1124-hr 1 " - Charlotte Rainfall=1. 00"
Prepared by (enter your company name here) Page 8
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Pond 3P: (Sand Filter 1)
Inflow Area = 1.180 ac, Inflow Depth = 0.13" for 1" - Charlotte event
Inflow = 0.11 cfs @ 12.16 hrs, Volume= 0.013 of
Outflow = 0.00 cfs @ 24.17 hrs, Volume= 0.013 af, Atten= 96%, Lag= 720.6 min
Primary = 0.00 cfs @ 24.17 hrs, Volume= 0.013 of
Routing by Stor-Ind method, Time Span= 0.00-200.00 hrs, dt= 0.10 hrs
Peak Elev= 526.31' @ 24.17 hrs Surf.Area= 1,506 sf Storage= 420 cf
Plug -Flow detention time= 1,677.6 min calculated for 0.013 of (100% of inflow)
Center -of -Mass det. time= 1,676.9 min ( 2,604.5 - 927.6 )
Volume
Invert Avail.Storage Storage
Description
#1
526.00'
8,858 cf Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation
Surf.Area
Inc.Store
Cum.Store
(feet)
(sq-ft)
(cubic -feet)
(cubic -feet)
526.00
1,233
0
0
527.00
2,125
1,679
1,679
528.00
3,432
2,779
4,458
529.00
5,368
4,400
8,858
Device Routinq Invert Outlet Devices
#1 Primary
523.31'
15.0" x 62.0' long Culvert RCP, square edge headwall, Ke= 0.500
Outlet Invert= 523.00' S= 0.0050 '/' Cc= 0.900 n= 0.012
#2 Device 1
526.00'
Exfiltration
Head (feet) 0.00 1.00 2.00 3.00 4.00
Disch. (cfs) 0.000 0.013 0.018 0.023 0.028
#3 Device 1
527.00'
1.0' 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
#4 Device 1
528.00'
9.0' 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 Primary
528.00'
5.0' long x 10.0' 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) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64
Primary OutFlow Max=0.00 cfs @ 24.17 hrs HW=526.31' (Free Discharge)
1=Culvert (Passes 0.00 cfs of 8.54 cfs potential flow)
2=Exfiltration (Custom Controls 0.00 cfs)
3=Broad-Crested Rectangular Weir ( Controls 0.00 cfs)
=Broad -Crested Rectangular Weir ( Controls 0.00 cfs)
= Broad-C rested Rectangular Weir ( Controls 0.00 cfs)

Pond
Type 1124-hr 1 " - Charlotte Rainfall=1. 00"
Prepared by {enter your company name here} Page 9
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Pond 3P: (Sand Filter 1)
Hydrograph
0.125
--
------ ------
------ ------ ------
0.12
--t------+------r---I---r
cfs
-rt---r--t------+------r------r--y---
0.11
0.115
-----1------
------II
0.11
0.105
--+
--
-----+------+------+------+--+------+y-`-A-`+--+-Q+1r�--+----Q-[�+--+---
--li -- ---II---
I------I
------II
-- --Inflow Area=11.1 VV at--
0.1
--1
--1---1---'---1---'---L---'---L--1---'---1------+--F-I---L_--'---L-_1---
0.095
--rt
--Ir--7---1i---r---li---r---li---r--rt---Ir--�G-QI1r�LG-�[C
0.09
--II
-----Ii------------II
I4�1�--
0.085
0.08
--+
--
-----+------+------+------+--+------+---+-}+yam-r----+------+--+f---
--li -----II---
---II---
------Ii
-- ---li -- ---is `VI Q1 --
0.075
--1
--1---1---'---1---'---L------L--1------1---'---L---I-
-L---'---L--1---
N
0.07
r-- Y-
--I--- r-
--I--- r-
-- r-- Y---I---r---I--- r--- I---r--Y---
....
0.065
--I
-----I---I---I---I---I---------I---I---
I -- -I- __ I ---I---I---I-------I-- -
0 006
- -+
-----+------+------+------+--+---+--+---+--+--+---+--+---+--+---
M0.055
--i------i------i---II---
0.05
--1
--1---1---'---+---'---L---'---L--1---'---1------L------L------L--1---
0.045
--
-----7---I---r---li---r---li---I---
------7---I---r---li---r---li---Ir------
0.04
0.035
--+
-----+------+------+------+--+------+---+--+--+---+------+--+---
0.03
--
--li ---
- -II- ----
-II --- Ir
0.025
--1
--1---1---'---1---'---L---'---L--1---'---1------L------L------L--L---
0.02
- --
-----7---Ir--r---li---r---li---r------Ir--7---I---r---li---r---li---Ir------
0.015
--
-----I------I---I---1
-
--I------ I------I---I- --+---I---1----------I---
0.01
--+
O.00cfs
-- - - - +-
+---+--+---+
-+------+--+--+--+---+-----+--+- -
0.005
--
- - - -
- --
0
0 10
20 30
40 50
60 70
80 90 100 110 120 130 140 150 160 170 180 190 200
Time (hours)
- Inflow
- Primary

Pond 1 Type 11 24-hr 1 " - Charlotte Rainfall= 1. 00 "
Prepared by (enter your company name here) Page 10
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Hydrograph for Pond 3P: (Sand Filter 1)
Time
Inflow
Storage
Elevation
Primary
(hours)
(cfs)
(cubic -feet)
(feet)
(cfs)
0.00
0.00
0
526.00
0.00
5.00
0.00
0
526.00
0.00
10.00
0.00
0
526.00
0.00
15.00
0.01
303
526.23
0.00
20.00
0.01
395
526.29
0.00
25.00
0.00
410
526.30
0.00
30.00
0.00
345
526.26
0.00
35.00
0.00
290
526.22
0.00
40.00
0.00
243
526.18
0.00
45.00
0.00
203
526.16
0.00
50.00
0.00
170
526.13
0.00
55.00
0.00
141
526.11
0.00
60.00
0.00
118
526.09
0.00
65.00
0.00
98
526.08
0.00
70.00
0.00
81
526.06
0.00
75.00
0.00
68
526.05
0.00
80.00
0.00
56
526.04
0.00
85.00
0.00
47
526.04
0.00
90.00
0.00
39
526.03
0.00
95.00
0.00
32
526.03
0.00
100.00
0.00
27
526.02
0.00
105.00
0.00
22
526.02
0.00
110.00
0.00
18
526.01
0.00
115.00
0.00
15
526.01
0.00
120.00
0.00
13
526.01
0.00
125.00
0.00
10
526.01
0.00
130.00
0.00
9
526.01
0.00
135.00
0.00
7
526.01
0.00
140.00
0.00
6
526.00
0.00
145.00
0.00
5
526.00
0.00
150.00
0.00
4
526.00
0.00
155.00
0.00
3
526.00
0.00
160.00
0.00
3
526.00
0.00
165.00
0.00
2
526.00
0.00
170.00
0.00
2
526.00
0.00
175.00
0.00
2
526.00
0.00
180.00
0.00
1
526.00
0.00
185.00
0.00
1
526.00
0.00
190.00
0.00
1
526.00
0.00
195.00
0.00
1
526.00
0.00
200.00
0.00
1
526.00
0.00

Pond 1 Type 11 24-hr 1 " - Charlotte Rainfall=1.00"
Prepared by (enter your company name here) Page 11
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Elevation Primary
(feet)
(cfs)
526.00
0.00
526.02
0.00
526.04
0.00
526.06
0.00
526.08
0.00
526.10
0.00
526.12
0.00
526.14
0.00
526.16
0.00
526.18
0.00
526.20
0.00
526.22
0.00
526.24
0.00
526.26
0.00
526.28
0.00
526.30
0.00
526.32
0.00
526.34
0.00
526.36
0.00
526.38
0.00
526.40
0.01
526.42
0.01
526.44
0.01
526.46
0.01
526.48
0.01
526.50
0.01
526.52
0.01
526.54
0.01
526.56
0.01
526.58
0.01
526.60
0.01
526.62
0.01
526.64
0.01
526.66
0.01
526.68
0.01
526.70
0.01
526.72
0.01
526.74
0.01
526.76
0.01
526.78
0.01
526.80
0.01
526.82
0.01
526.84
0.01
526.86
0.01
526.88
0.01
526.90
0.01
526.92
0.01
526.94
0.01
526.96
0.01
526.98
0.01
527.00
0.01
527.02
0.02
Stage -Discharge for Pond 3P: (Sand Filter 1)
Elevation Primary
(feet)
(cfs)
527.04
0.04
527.06
0.05
527.08
0.08
527.10
0.10
527.12
0.13
527.14
0.16
527.16
0.19
527.18
0.23
527.20
0.26
527.22
0.30
527.24
0.35
527.26
0.39
527.28
0.44
527.30
0.48
527.32
0.53
527.34
0.59
527.36
0.64
527.38
0.70
527.40
0.75
527.42
0.81
527.44
0.88
527.46
0.94
527.48
1.01
527.50
1.08
527.52
1.15
527.54
1.22
527.56
1.29
527.58
1.37
527.60
1.45
527.62
1.53
527.64
1.62
527.66
1.70
527.68
1.79
527.70
1.88
527.72
1.98
527.74
2.08
527.76
2.17
527.78
2.28
527.80
2.38
527.82
2.47
527.84
2.56
527.86
2.65
527.88
2.75
527.90
2.84
527.92
2.94
527.94
3.04
527.96
3.14
527.98
3.24
528.00
3.34
528.02
3.54
528.04
3.84
528.06
4.19
Elevation Primary
(feet)
(cfs)
528.08
4.60
528.10
5.04
528.12
5.52
528.14
6.03
528.16
6.58
528.18
7.15
528.20
7.75
528.22
8.39
528.24
9.06
528.26
9.76
528.28
10.49
528.30
11.24
528.32
12.03
528.34
12.83
528.36
13.66
528.38
14.52
528.40
15.38
528.42
15.67
528.44
15.97
528.46
16.28
528.48
16.60
528.50
16.93
528.52
17.27
528.54
17.61
528.56
17.97
528.58
18.33
528.60
18.70
528.62
19.04
528.64
19.39
528.66
19.74
528.68
20.10
528.70
20.46
528.72
20.83
528.74
21.20
528.76
21.57
528.78
21.95
528.80
22.33
528.82
22.72
528.84
23.11
528.86
23.51
528.88
23.91
528.90
24.31
528.92
24.72
528.94
25.13
528.96
25.54
528.98
25.96
529.00
26.39
529.02
26.82
529.04
27.26
529.06
27.71
529.08
28.16
529.10
28.61
Elevation Primary
(feet)
(cfs)
529.12
29.07
529.14
29.53
529.16
29.99
529.18
30.46
529.20
30.94
529.22
31.39
529.24
31.85
529.26
32.32
529.28
32.78
529.30
33.25
529.32
33.72
529.34
34.20
529.36
34.67
529.38
35.15
529.40
35.64
529.42
36.11
529.44
36.59
529.46
37.07
529.48
37.55
529.50
38.04
529.52
38.53
529.54
39.02
529.56
39.51
529.58
40.00
529.60
40.50
529.62
41.02
529.64
41.56
529.66
42.09
529.68
42.63
529.70
43.17
529.72
43.71
529.74
44.26
529.76
44.81
529.78
45.36
529.80
45.91
529.82
46.47
529.84
47.03
529.86
47.60
529.88
48.16
529.90
48.73
529.92
49.31
529.94
49.88
529.96
50.46
529.98
51.04
530.00
51.62

Pond 1 Type 11 24-hr 1 " - Charlotte Rainfall= 1. 00 "
Prepared by (enter your company name here) Page 12
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Stage -Area -Storage for Pond 3P: (Sand Filter 1)
Elevation
Surface
Storage
(feet)
(sq-ft)
(cubic -feet)
526.00
1,233
0
526.05
1,278
63
526.10
1,322
128
526.15
1,367
195
526.20
1,411
264
526.25
1,456
336
526.30
1,501
410
526.35
1,545
486
526.40
1,590
565
526.45
1,634
645
526.50
1,679
728
526.55
1,724
813
526.60
1,768
900
526.65
1,813
990
526.70
1,857
1,082
526.75
1,902
1,176
526.80
1,947
1,272
526.85
1,991
1,370
526.90
2,036
1,471
526.95
2,080
1,574
527.00
2,125
1,679
527.05
2,190
1,787
527.10
2,256
1,898
527.15
2,321
2,012
527.20
2,386
2,130
527.25
2,452
2,251
527.30
2,517
2,375
527.35
2,582
2,503
527.40
2,648
2,634
527.45
2,713
2,768
527.50
2,779
2,905
527.55
2,844
3,045
527.60
2,909
3,189
527.65
2,975
3,336
527.70
3,040
3,487
527.75
3,105
3,640
527.80
3,171
3,797
527.85
3,236
3,957
527.90
3,301
4,121
527.95
3,367
4,288
528.00
3,432
4,458
528.05
3,529
4,632
528.10
3,626
4,810
528.15
3,722
4,994
528.20
3,819
5,183
528.25
3,916
5,376
528.30
4,013
5,574
528.35
4,110
5,777
528.40
4,206
5,985
528.45
4,303
6,198
528.50
4,400
6,416
528.55
4,497
6,638
Elevation
Surface
Storage
(feet)
(sq-ft)
(cubic -feet)
528.60
4,594
6,865
528.65
4,690
7,097
528.70
4,787
7,334
528.75
4,884
7,576
528.80
4,981
7,823
528.85
5,078
8,074
528.90
5,174
8,330
528.95
5,271
8,592
529.00
5,368
8,858
529.05
5,368
8,858
529.10
5,368
8,858
529.15
5,368
8,858
529.20
5,368
8,858
529.25
5,368
8,858
529.30
5,368
8,858
529.35
5,368
8,858
529.40
5,368
8,858
529.45
5,368
8,858
529.50
5,368
8,858
529.55
5,368
8,858
529.60
5,368
8,858
529.65
5,368
8,858
529.70
5,368
8,858
529.75
5,368
8,858
529.80
5,368
8,858
529.85
5,368
8,858
529.90
5,368
8,858
529.95
5,368
8,858
530.00
5,368
8,858

Pond 1 Type 1124-hr 1-Year Charlotte Rainfall=2.58"
Prepared by (enter your company name here) Page 13
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Time span =0.00-200.00 hrs, dt=0.10 hrs, 2001 points
Runoff by SCS TR-20 method, UH=SCS
Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method
Subcatchment 1S: (Predeveloped) Runoff Area=1.180 ac Runoff Depth=0.70"
Tc=18.4 min CN=75 Runoff=0.85 cfs 0.069 of
Subcatchment 2S: (Post Developed) Runoff Area=1.180 ac Runoff Depth=1.12"
Tc=17.6 min CN=83 Runoff=1.52 cfs 0.110 of
Pond 3P: (Sand Filter 1) Peak Elev=527.22' Storage=2,187 cf Inflow=1.52 cfs 0.110 of
Outflow=0.31 cfs 0.110 of
Total Runoff Area = 2.360 ac Runoff Volume = 0.178 of Average Runoff Depth = 0.91"
100.00% Pervious Area = 2.360 ac 0.00% Impervious Area = 0.000 ac

Pond 1 Type 1124-hr 1-Year Charlotte Rainfall=2.58"
Prepared by {enter your company name here} Page 14
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Subcatchment 1 S: (Predeveloped)
Runoff = 0.85 cfs @ 12.13 hrs, Volume= 0.069 af, Depth= 0.70"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-200.00 hrs, dt= 0.10 hrs
Type II 24-hr 1-Year Charlotte Rainfall=2.58"
Area (ac) CN Description
1.180 75 See Calculations
1.180 Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
18.4 Direct Entry,
Subcatchment 1 S: (Predeveloped)
Hydrograph
0.95 -- ------ --- --
------ - - - - -- - - - - -- - - - - -- - - - - -- - - - - -- - - - - -- --
0.9 0.85Cfs -- --- -- ------------+------+------ ------ ------ ------ --
0.85 --L --1---L---L--L---'---L---'---L---'---L------L------L------L------L--
0.8 -- -- -- --- -- -- --type-Il�-�4-hr Ypa--(harlo�te-
0.75 --- --li -- ---li -- ------ ---li -RaIrt idll12-.50 '
0.7 ---� --li -- it ---li -- �i---II--- it ---li -- �i---II--- it ---'i- � ----- �i---------
Rdnoff Atea-1.180 tic
0.65 -- --li -----Ir-----li---T---li --T---li---T------r---I---r---I---r---I---r-0.6 -
-- ' __I I I I I I I I I I
_R4naff Volulme#0.069,a#_
Hl
0.55 -- --I--- ---r--------+------T------+------+--Ftunoff-peptic-0-7( '-
I I I I I I I I I I I I I I I
0.5 -- -- --- -- ---------+--- +--- ------'Tc=�1-8.- min
0 0.45 --L --'---L---L--L---'---L---'---L---'---L------L------L------L------r--
LL
0.4-- - -- - -- - -- --- +I ------ -- _ CN-'75_
-- ----
0.35 - -
-I' --'------'------'--- +---'--- +---'--- +---'------'------'---------'---
0.3--
0.25 --- - -li- - - - -li - ---
I
0.2 -i r--7---r--7---r--r---r--r---r--r---I---r---I---r---I---r---I---r--
0.15 --t-- I -- - t- - -Ir -- ---I---t------t---li---t---li---t---li---r---
li---r---li---Ir--
0.1 --+ --+--+---+--+---+--+---+--+---+--+--+---+--+---+--+---+------+--
0.05 --+-+--+---+--+---+--+---+--+---+--+--+---+--+---+--+---+------+--
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200
Time (hours)
— Runoff

Pond 1 Type 1124-hr 1-Year Charlotte Rainfall=2.58"
Prepared by (enter your company name here) Page 15
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Hydrograph for Subcatchment 1S: (Predeveloped)
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
0.00
0.00
0.00
0.00
2.00
0.06
0.00
0.00
4.00
0.12
0.00
0.00
6.00
0.21
0.00
0.00
8.00
0.31
0.00
0.00
10.00
0.47
0.00
0.00
12.00
1.71
0.25
0.52
14.00
2.12
0.44
0.07
16.00
2.27
0.52
0.04
18.00
2.38
0.58
0.03
20.00
2.46
0.63
0.02
22.00
2.52
0.66
0.02
24.00
2.58
0.70
0.02
26.00
2.58
0.70
0.00
28.00
2.58
0.70
0.00
30.00
2.58
0.70
0.00
32.00
2.58
0.70
0.00
34.00
2.58
0.70
0.00
36.00
2.58
0.70
0.00
38.00
2.58
0.70
0.00
40.00
2.58
0.70
0.00
42.00
2.58
0.70
0.00
44.00
2.58
0.70
0.00
46.00
2.58
0.70
0.00
48.00
2.58
0.70
0.00
50.00
2.58
0.70
0.00
52.00
2.58
0.70
0.00
54.00
2.58
0.70
0.00
56.00
2.58
0.70
0.00
58.00
2.58
0.70
0.00
60.00
2.58
0.70
0.00
62.00
2.58
0.70
0.00
64.00
2.58
0.70
0.00
66.00
2.58
0.70
0.00
68.00
2.58
0.70
0.00
70.00
2.58
0.70
0.00
72.00
2.58
0.70
0.00
74.00
2.58
0.70
0.00
76.00
2.58
0.70
0.00
78.00
2.58
0.70
0.00
80.00
2.58
0.70
0.00
82.00
2.58
0.70
0.00
84.00
2.58
0.70
0.00
86.00
2.58
0.70
0.00
88.00
2.58
0.70
0.00
90.00
2.58
0.70
0.00
92.00
2.58
0.70
0.00
94.00
2.58
0.70
0.00
96.00
2.58
0.70
0.00
98.00
2.58
0.70
0.00
100.00
2.58
0.70
0.00
102.00
2.58
0.70
0.00
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
104.00
2.58
0.70
0.00
106.00
2.58
0.70
0.00
108.00
2.58
0.70
0.00
110.00
2.58
0.70
0.00
112.00
2.58
0.70
0.00
114.00
2.58
0.70
0.00
116.00
2.58
0.70
0.00
118.00
2.58
0.70
0.00
120.00
2.58
0.70
0.00
122.00
2.58
0.70
0.00
124.00
2.58
0.70
0.00
126.00
2.58
0.70
0.00
128.00
2.58
0.70
0.00
130.00
2.58
0.70
0.00
132.00
2.58
0.70
0.00
134.00
2.58
0.70
0.00
136.00
2.58
0.70
0.00
138.00
2.58
0.70
0.00
140.00
2.58
0.70
0.00
142.00
2.58
0.70
0.00
144.00
2.58
0.70
0.00
146.00
2.58
0.70
0.00
148.00
2.58
0.70
0.00
150.00
2.58
0.70
0.00
152.00
2.58
0.70
0.00
154.00
2.58
0.70
0.00
156.00
2.58
0.70
0.00
158.00
2.58
0.70
0.00
160.00
2.58
0.70
0.00
162.00
2.58
0.70
0.00
164.00
2.58
0.70
0.00
166.00
2.58
0.70
0.00
168.00
2.58
0.70
0.00
170.00
2.58
0.70
0.00
172.00
2.58
0.70
0.00
174.00
2.58
0.70
0.00
176.00
2.58
0.70
0.00
178.00
2.58
0.70
0.00
180.00
2.58
0.70
0.00
182.00
2.58
0.70
0.00
184.00
2.58
0.70
0.00
186.00
2.58
0.70
0.00
188.00
2.58
0.70
0.00
190.00
2.58
0.70
0.00
192.00
2.58
0.70
0.00
194.00
2.58
0.70
0.00
196.00
2.58
0.70
0.00
198.00
2.58
0.70
0.00
200.00
2.58
0.70
0.00

Pond 1 Type 1124-hr 1-Year Charlotte Rainfall=2.58"
Prepared by {enter your company name here} Page 16
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Subcatchment 2S: (Post Developed)
Runoff = 1.52 cfs @ 12.11 hrs, Volume= 0.110 af, Depth= 1.12"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-200.00 hrs, dt= 0.10 hrs
Type II 24-hr 1-Year Charlotte Rainfall=2.58"
Area (ac) CN Description
1.180 83
1.180 Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
17.6 Direct Entry,
Subcatchment 2S: (Post Developed)
Hydrograph
1.52 cfs
Type II �4-1�r 1.,Ye;ir charlotte
Rpinfpll=?.50"
Ounofl Arga=,1.100 ac
Rynolf V9Iuime=0.410 of
Runoff Depth=)A �"
tc-17.6 min
0=83
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200
Time (hours)
— Runoff

Pond 1 Type 1124-hr 1-Year Charlotte Rainfall=2.58"
Prepared by (enter your company name here) Page 17
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Hydrograph for Subcatchment 2S: (Post Developed)
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
0.00
0.00
0.00
0.00
2.00
0.06
0.00
0.00
4.00
0.12
0.00
0.00
6.00
0.21
0.00
0.00
8.00
0.31
0.00
0.00
10.00
0.47
0.00
0.00
12.00
1.71
0.51
1.11
14.00
2.12
0.78
0.09
16.00
2.27
0.89
0.06
18.00
2.38
0.96
0.04
20.00
2.46
1.02
0.03
22.00
2.52
1.07
0.03
24.00
2.58
1.12
0.03
26.00
2.58
1.12
0.00
28.00
2.58
1.12
0.00
30.00
2.58
1.12
0.00
32.00
2.58
1.12
0.00
34.00
2.58
1.12
0.00
36.00
2.58
1.12
0.00
38.00
2.58
1.12
0.00
40.00
2.58
1.12
0.00
42.00
2.58
1.12
0.00
44.00
2.58
1.12
0.00
46.00
2.58
1.12
0.00
48.00
2.58
1.12
0.00
50.00
2.58
1.12
0.00
52.00
2.58
1.12
0.00
54.00
2.58
1.12
0.00
56.00
2.58
1.12
0.00
58.00
2.58
1.12
0.00
60.00
2.58
1.12
0.00
62.00
2.58
1.12
0.00
64.00
2.58
1.12
0.00
66.00
2.58
1.12
0.00
68.00
2.58
1.12
0.00
70.00
2.58
1.12
0.00
72.00
2.58
1.12
0.00
74.00
2.58
1.12
0.00
76.00
2.58
1.12
0.00
78.00
2.58
1.12
0.00
80.00
2.58
1.12
0.00
82.00
2.58
1.12
0.00
84.00
2.58
1.12
0.00
86.00
2.58
1.12
0.00
88.00
2.58
1.12
0.00
90.00
2.58
1.12
0.00
92.00
2.58
1.12
0.00
94.00
2.58
1.12
0.00
96.00
2.58
1.12
0.00
98.00
2.58
1.12
0.00
100.00
2.58
1.12
0.00
102.00
2.58
1.12
0.00
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
104.00
2.58
1.12
0.00
106.00
2.58
1.12
0.00
108.00
2.58
1.12
0.00
110.00
2.58
1.12
0.00
112.00
2.58
1.12
0.00
114.00
2.58
1.12
0.00
116.00
2.58
1.12
0.00
118.00
2.58
1.12
0.00
120.00
2.58
1.12
0.00
122.00
2.58
1.12
0.00
124.00
2.58
1.12
0.00
126.00
2.58
1.12
0.00
128.00
2.58
1.12
0.00
130.00
2.58
1.12
0.00
132.00
2.58
1.12
0.00
134.00
2.58
1.12
0.00
136.00
2.58
1.12
0.00
138.00
2.58
1.12
0.00
140.00
2.58
1.12
0.00
142.00
2.58
1.12
0.00
144.00
2.58
1.12
0.00
146.00
2.58
1.12
0.00
148.00
2.58
1.12
0.00
150.00
2.58
1.12
0.00
152.00
2.58
1.12
0.00
154.00
2.58
1.12
0.00
156.00
2.58
1.12
0.00
158.00
2.58
1.12
0.00
160.00
2.58
1.12
0.00
162.00
2.58
1.12
0.00
164.00
2.58
1.12
0.00
166.00
2.58
1.12
0.00
168.00
2.58
1.12
0.00
170.00
2.58
1.12
0.00
172.00
2.58
1.12
0.00
174.00
2.58
1.12
0.00
176.00
2.58
1.12
0.00
178.00
2.58
1.12
0.00
180.00
2.58
1.12
0.00
182.00
2.58
1.12
0.00
184.00
2.58
1.12
0.00
186.00
2.58
1.12
0.00
188.00
2.58
1.12
0.00
190.00
2.58
1.12
0.00
192.00
2.58
1.12
0.00
194.00
2.58
1.12
0.00
196.00
2.58
1.12
0.00
198.00
2.58
1.12
0.00
200.00
2.58
1.12
0.00

Pond 1 Type 1124-hr 1-Year Charlotte Rainfall=2.58"
Prepared by (enter your company name here) Page 18
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Pond 3P: (Sand Filter 1)
Inflow Area = 1.180 ac, Inflow Depth = 1.12" for 1-Year Charlotte event
Inflow = 1.52 cfs @ 12.11 hrs, Volume= 0.110 of
Outflow = 0.31 cfs @ 12.58 hrs, Volume= 0.11Oaf, Atten= 79%, Lag= 28.1 min
Primary = 0.31 cfs @ 12.58 hrs, Volume= 0.110 of
Routing by Stor-Ind method, Time Span= 0.00-200.00 hrs, dt= 0.10 hrs
Peak Elev= 527.22' @ 12.58 hrs Surf.Area= 2,417 sf Storage= 2,187 cf
Plug -Flow detention time= 954.4 min calculated for 0.110 of (100% of inflow)
Center -of -Mass det. time= 953.9 min ( 1,805.0 - 851.1 )
Volume
Invert Avail.Storage Storage
Description
#1
526.00'
8,858 cf Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation
Surf.Area
Inc.Store
Cum.Store
(feet)
(sq-ft)
(cubic -feet)
(cubic -feet)
526.00
1,233
0
0
527.00
2,125
1,679
1,679
528.00
3,432
2,779
4,458
529.00
5,368
4,400
8,858
Device Routinq Invert Outlet Devices
#1 Primary
523.31'
15.0" x 62.0' long Culvert RCP, square edge headwall, Ke= 0.500
Outlet Invert= 523.00' S= 0.0050 '/' Cc= 0.900 n= 0.012
#2 Device 1
526.00'
Exfiltration
Head (feet) 0.00 1.00 2.00 3.00 4.00
Disch. (cfs) 0.000 0.013 0.018 0.023 0.028
#3 Device 1
527.00'
1.0' 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
#4 Device 1
528.00'
9.0' 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 Primary
528.00'
5.0' long x 10.0' 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) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64
Primary OutFlow Max=0.31 cfs @ 12.58 hrs HW=527.22' (Free Discharge)
1=Culvert (Passes 0.31 cfs of 10.27 cfs potential flow)
2=Exfiltration (Custom Controls 0.01 cfs)
3=Broad-Crested Rectangular Weir (Weir Controls 0.30 cfs @ 1.33 fps)
=Broad -Crested Rectangular Weir ( Controls 0.00 cfs)
= Broad-C rested Rectangular Weir ( Controls 0.00 cfs)

Pond 1
Type 11 24-hr 1-Year Charlotte Rainfall=2.58"
Prepared by {enter your company name here} Page 19
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Pond 3P: (Sand Filter 1)
Hydrograph
1.52 cfs
Inflow Area=1.180 a+c
Peak Elev=527622'
Storage=2, �'I 87 of
0.31 cfs
10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200
Time (hours)
— Inflow
— Primary

Pond 1 Type 1124-hr 1-Year Charlotte Rainfall=2.58"
Prepared by (enter your company name here) Page 20
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Hydrograph for Pond 3P: (Sand Filter 1)
Time
Inflow
Storage
Elevation
Primary
(hours)
(cfs)
(cubic -feet)
(feet)
(cfs)
0.00
0.00
0
526.00
0.00
5.00
0.00
0
526.00
0.00
10.00
0.00
2
526.00
0.00
15.00
0.07
1,859
527.08
0.08
20.00
0.03
1,763
527.04
0.04
25.00
0.00
1,682
527.00
0.01
30.00
0.00
1,460
526.89
0.01
35.00
0.00
1,262
526.80
0.01
40.00
0.00
1,087
526.70
0.01
45.00
0.00
933
526.62
0.01
50.00
0.00
797
526.54
0.01
55.00
0.00
679
526.47
0.01
60.00
0.00
577
526.41
0.01
65.00
0.00
488
526.35
0.00
70.00
0.00
412
526.30
0.00
75.00
0.00
347
526.26
0.00
80.00
0.00
291
526.22
0.00
85.00
0.00
244
526.19
0.00
90.00
0.00
204
526.16
0.00
95.00
0.00
170
526.13
0.00
100.00
0.00
142
526.11
0.00
105.00
0.00
118
526.09
0.00
110.00
0.00
98
526.08
0.00
115.00
0.00
82
526.06
0.00
120.00
0.00
68
526.05
0.00
125.00
0.00
56
526.04
0.00
130.00
0.00
47
526.04
0.00
135.00
0.00
39
526.03
0.00
140.00
0.00
32
526.03
0.00
145.00
0.00
27
526.02
0.00
150.00
0.00
22
526.02
0.00
155.00
0.00
18
526.01
0.00
160.00
0.00
15
526.01
0.00
165.00
0.00
13
526.01
0.00
170.00
0.00
10
526.01
0.00
175.00
0.00
9
526.01
0.00
180.00
0.00
7
526.01
0.00
185.00
0.00
6
526.00
0.00
190.00
0.00
5
526.00
0.00
195.00
0.00
4
526.00
0.00
200.00
0.00
3
526.00
0.00

Pond 1 Type 1124-hr 1-Year Charlotte Rainfall=2.58"
Prepared by (enter your company name here) Page 21
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Elevation Primary
(feet)
(cfs)
526.00
0.00
526.02
0.00
526.04
0.00
526.06
0.00
526.08
0.00
526.10
0.00
526.12
0.00
526.14
0.00
526.16
0.00
526.18
0.00
526.20
0.00
526.22
0.00
526.24
0.00
526.26
0.00
526.28
0.00
526.30
0.00
526.32
0.00
526.34
0.00
526.36
0.00
526.38
0.00
526.40
0.01
526.42
0.01
526.44
0.01
526.46
0.01
526.48
0.01
526.50
0.01
526.52
0.01
526.54
0.01
526.56
0.01
526.58
0.01
526.60
0.01
526.62
0.01
526.64
0.01
526.66
0.01
526.68
0.01
526.70
0.01
526.72
0.01
526.74
0.01
526.76
0.01
526.78
0.01
526.80
0.01
526.82
0.01
526.84
0.01
526.86
0.01
526.88
0.01
526.90
0.01
526.92
0.01
526.94
0.01
526.96
0.01
526.98
0.01
527.00
0.01
527.02
0.02
Stage -Discharge for Pond 3P: (Sand Filter 1)
Elevation Primary
(feet)
(cfs)
527.04
0.04
527.06
0.05
527.08
0.08
527.10
0.10
527.12
0.13
527.14
0.16
527.16
0.19
527.18
0.23
527.20
0.26
527.22
0.30
527.24
0.35
527.26
0.39
527.28
0.44
527.30
0.48
527.32
0.53
527.34
0.59
527.36
0.64
527.38
0.70
527.40
0.75
527.42
0.81
527.44
0.88
527.46
0.94
527.48
1.01
527.50
1.08
527.52
1.15
527.54
1.22
527.56
1.29
527.58
1.37
527.60
1.45
527.62
1.53
527.64
1.62
527.66
1.70
527.68
1.79
527.70
1.88
527.72
1.98
527.74
2.08
527.76
2.17
527.78
2.28
527.80
2.38
527.82
2.47
527.84
2.56
527.86
2.65
527.88
2.75
527.90
2.84
527.92
2.94
527.94
3.04
527.96
3.14
527.98
3.24
528.00
3.34
528.02
3.54
528.04
3.84
528.06
4.19
Elevation Primary
(feet)
(cfs)
528.08
4.60
528.10
5.04
528.12
5.52
528.14
6.03
528.16
6.58
528.18
7.15
528.20
7.75
528.22
8.39
528.24
9.06
528.26
9.76
528.28
10.49
528.30
11.24
528.32
12.03
528.34
12.83
528.36
13.66
528.38
14.52
528.40
15.38
528.42
15.67
528.44
15.97
528.46
16.28
528.48
16.60
528.50
16.93
528.52
17.27
528.54
17.61
528.56
17.97
528.58
18.33
528.60
18.70
528.62
19.04
528.64
19.39
528.66
19.74
528.68
20.10
528.70
20.46
528.72
20.83
528.74
21.20
528.76
21.57
528.78
21.95
528.80
22.33
528.82
22.72
528.84
23.11
528.86
23.51
528.88
23.91
528.90
24.31
528.92
24.72
528.94
25.13
528.96
25.54
528.98
25.96
529.00
26.39
529.02
26.82
529.04
27.26
529.06
27.71
529.08
28.16
529.10
28.61
Elevation Primary
(feet)
(cfs)
529.12
29.07
529.14
29.53
529.16
29.99
529.18
30.46
529.20
30.94
529.22
31.39
529.24
31.85
529.26
32.32
529.28
32.78
529.30
33.25
529.32
33.72
529.34
34.20
529.36
34.67
529.38
35.15
529.40
35.64
529.42
36.11
529.44
36.59
529.46
37.07
529.48
37.55
529.50
38.04
529.52
38.53
529.54
39.02
529.56
39.51
529.58
40.00
529.60
40.50
529.62
41.02
529.64
41.56
529.66
42.09
529.68
42.63
529.70
43.17
529.72
43.71
529.74
44.26
529.76
44.81
529.78
45.36
529.80
45.91
529.82
46.47
529.84
47.03
529.86
47.60
529.88
48.16
529.90
48.73
529.92
49.31
529.94
49.88
529.96
50.46
529.98
51.04
530.00
51.62

Pond 1 Type 1124-hr 1-Year Charlotte Rainfall=2.58"
Prepared by (enter your company name here) Page 22
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Stage -Area -Storage for Pond 3P: (Sand Filter 1)
Elevation
Surface
Storage
(feet)
(sq-ft)
(cubic -feet)
526.00
1,233
0
526.05
1,278
63
526.10
1,322
128
526.15
1,367
195
526.20
1,411
264
526.25
1,456
336
526.30
1,501
410
526.35
1,545
486
526.40
1,590
565
526.45
1,634
645
526.50
1,679
728
526.55
1,724
813
526.60
1,768
900
526.65
1,813
990
526.70
1,857
1,082
526.75
1,902
1,176
526.80
1,947
1,272
526.85
1,991
1,370
526.90
2,036
1,471
526.95
2,080
1,574
527.00
2,125
1,679
527.05
2,190
1,787
527.10
2,256
1,898
527.15
2,321
2,012
527.20
2,386
2,130
527.25
2,452
2,251
527.30
2,517
2,375
527.35
2,582
2,503
527.40
2,648
2,634
527.45
2,713
2,768
527.50
2,779
2,905
527.55
2,844
3,045
527.60
2,909
3,189
527.65
2,975
3,336
527.70
3,040
3,487
527.75
3,105
3,640
527.80
3,171
3,797
527.85
3,236
3,957
527.90
3,301
4,121
527.95
3,367
4,288
528.00
3,432
4,458
528.05
3,529
4,632
528.10
3,626
4,810
528.15
3,722
4,994
528.20
3,819
5,183
528.25
3,916
5,376
528.30
4,013
5,574
528.35
4,110
5,777
528.40
4,206
5,985
528.45
4,303
6,198
528.50
4,400
6,416
528.55
4,497
6,638
Elevation
Surface
Storage
(feet)
(sq-ft)
(cubic -feet)
528.60
4,594
6,865
528.65
4,690
7,097
528.70
4,787
7,334
528.75
4,884
7,576
528.80
4,981
7,823
528.85
5,078
8,074
528.90
5,174
8,330
528.95
5,271
8,592
529.00
5,368
8,858
529.05
5,368
8,858
529.10
5,368
8,858
529.15
5,368
8,858
529.20
5,368
8,858
529.25
5,368
8,858
529.30
5,368
8,858
529.35
5,368
8,858
529.40
5,368
8,858
529.45
5,368
8,858
529.50
5,368
8,858
529.55
5,368
8,858
529.60
5,368
8,858
529.65
5,368
8,858
529.70
5,368
8,858
529.75
5,368
8,858
529.80
5,368
8,858
529.85
5,368
8,858
529.90
5,368
8,858
529.95
5,368
8,858
530.00
5,368
8,858

Pond 1 Charlotte 6-hr 2-yr 2 Year -Charlotte Rainfall=2.28"
Prepared by (enter your company name here) Page 23
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Time span =0.00-200.00 hrs, dt=0.10 hrs, 2001 points
Runoff by SCS TR-20 method, UH=SCS
Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method
Subcatchment 1S: (Predeveloped) Runoff Area=1.180 ac Runoff Depth=0.53"
Tc=18.4 min CN=75 Runoff=0.79 cfs 0.052 of
Subcatchment 2S: (Post Developed) Runoff Area=1.180 ac Runoff Depth=0.89"
Tc=17.6 min CN=83 Runoff=1.53 cfs 0.088 of
Pond 3P: (Sand Filter 1) Peak Elev=527.25' Storage=2,250 cf Inflow=1.53 cfs 0.088 of
Outflow=0.37 cfs 0.088 of
Total Runoff Area = 2.360 ac Runoff Volume = 0.140 of Average Runoff Depth = 0.71"
100.00% Pervious Area = 2.360 ac 0.00% Impervious Area = 0.000 ac

Pond 1 Charlotte 6-hr 2-yr 2 Year -Charlotte Rainfall=2.28"
Prepared by {enter your company name here} Page 24
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Subcatchment 1 S: (Predeveloped)
Runoff = 0.79 cfs @ 3.39 hrs, Volume= 0.052 af, Depth= 0.53"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-200.00 hrs, dt= 0.10 hrs
Charlotte 6-hr 2-yr 2 Year -Charlotte Rainfall=2.28"
Area (ac) CN Description
1.180 75 See Calculations
1.180 Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
18.4 Direct Entry,
Subcatchment 1 S: (Predeveloped)
Hydrograph
0.09-c-fs
0-------I---------T------I_--- TII-----T-----------T---------T---------
0.75---+------+------+----Chr-a-fl-ll-W-r}-e--6IIi---h-I
p
0.7-J--- L--L---L---L-1----LI--- L---I- -- L---I- - -L
- I -' -- -I-G`-yr'r--s rtQ"----
-
-
-
0.65 - i - i
0.6- T------ T--- T-- T- - -- ---T---I-Rainfall-228"
0.55 -L------L---L--L------L------+------+------L------L------L------L--
y 0.5 -- - - -- - --- - --- - --- - ----F'unoff'�-ArearI,I8p-A-C--
0.45 - --- -- --- --- - - I--- -----T-----Runoff VOW-me-01.052-af-
0.35-L---'---L---L--L---1---L---'---L------L---'Rwn0fDepttv=O.5$.
0.3--'i---'i -- I'i - - -'i -- I'i-- -'i--- I'i - - -II I I I M, I"'` �+I I
c=18.'mi'In--
0.25 -r---r--r---r--r---I---r---
r--r---r--r---I---r---I---r---I---r---I--r--
0.2-L------L---L--L------L------+------+------L------L-----_ 04=15-
0.15-L'---'------'------'------'------'------'------'------'---------L---
0.1--i---i -----i-----i---r - - -i -- ---I--- I - - -i---------�i---i---T -- -
i---i ---
0.05 +------+---+--+------+------+------+------+------r------+------+--
0
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200
Time (hours)
— Runoff

Pond 1 Charlotte 6-hr 2-yr 2 Year -Charlotte Rainfall=2.28"
Prepared by (enter your company name here) Page 25
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Hydrograph for Subcatchment 1S: (Predeveloped)
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
0.00
0.00
0.00
0.00
2.00
0.25
0.00
0.00
4.00
2.01
0.39
0.21
6.00
2.28
0.53
0.06
8.00
2.28
0.53
0.00
10.00
2.28
0.53
0.00
12.00
2.28
0.53
0.00
14.00
2.28
0.53
0.00
16.00
2.28
0.53
0.00
18.00
2.28
0.53
0.00
20.00
2.28
0.53
0.00
22.00
2.28
0.53
0.00
24.00
2.28
0.53
0.00
26.00
2.28
0.53
0.00
28.00
2.28
0.53
0.00
30.00
2.28
0.53
0.00
32.00
2.28
0.53
0.00
34.00
2.28
0.53
0.00
36.00
2.28
0.53
0.00
38.00
2.28
0.53
0.00
40.00
2.28
0.53
0.00
42.00
2.28
0.53
0.00
44.00
2.28
0.53
0.00
46.00
2.28
0.53
0.00
48.00
2.28
0.53
0.00
50.00
2.28
0.53
0.00
52.00
2.28
0.53
0.00
54.00
2.28
0.53
0.00
56.00
2.28
0.53
0.00
58.00
2.28
0.53
0.00
60.00
2.28
0.53
0.00
62.00
2.28
0.53
0.00
64.00
2.28
0.53
0.00
66.00
2.28
0.53
0.00
68.00
2.28
0.53
0.00
70.00
2.28
0.53
0.00
72.00
2.28
0.53
0.00
74.00
2.28
0.53
0.00
76.00
2.28
0.53
0.00
78.00
2.28
0.53
0.00
80.00
2.28
0.53
0.00
82.00
2.28
0.53
0.00
84.00
2.28
0.53
0.00
86.00
2.28
0.53
0.00
88.00
2.28
0.53
0.00
90.00
2.28
0.53
0.00
92.00
2.28
0.53
0.00
94.00
2.28
0.53
0.00
96.00
2.28
0.53
0.00
98.00
2.28
0.53
0.00
100.00
2.28
0.53
0.00
102.00
2.28
0.53
0.00
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
104.00
2.28
0.53
0.00
106.00
2.28
0.53
0.00
108.00
2.28
0.53
0.00
110.00
2.28
0.53
0.00
112.00
2.28
0.53
0.00
114.00
2.28
0.53
0.00
116.00
2.28
0.53
0.00
118.00
2.28
0.53
0.00
120.00
2.28
0.53
0.00
122.00
2.28
0.53
0.00
124.00
2.28
0.53
0.00
126.00
2.28
0.53
0.00
128.00
2.28
0.53
0.00
130.00
2.28
0.53
0.00
132.00
2.28
0.53
0.00
134.00
2.28
0.53
0.00
136.00
2.28
0.53
0.00
138.00
2.28
0.53
0.00
140.00
2.28
0.53
0.00
142.00
2.28
0.53
0.00
144.00
2.28
0.53
0.00
146.00
2.28
0.53
0.00
148.00
2.28
0.53
0.00
150.00
2.28
0.53
0.00
152.00
2.28
0.53
0.00
154.00
2.28
0.53
0.00
156.00
2.28
0.53
0.00
158.00
2.28
0.53
0.00
160.00
2.28
0.53
0.00
162.00
2.28
0.53
0.00
164.00
2.28
0.53
0.00
166.00
2.28
0.53
0.00
168.00
2.28
0.53
0.00
170.00
2.28
0.53
0.00
172.00
2.28
0.53
0.00
174.00
2.28
0.53
0.00
176.00
2.28
0.53
0.00
178.00
2.28
0.53
0.00
180.00
2.28
0.53
0.00
182.00
2.28
0.53
0.00
184.00
2.28
0.53
0.00
186.00
2.28
0.53
0.00
188.00
2.28
0.53
0.00
190.00
2.28
0.53
0.00
192.00
2.28
0.53
0.00
194.00
2.28
0.53
0.00
196.00
2.28
0.53
0.00
198.00
2.28
0.53
0.00
200.00
2.28
0.53
0.00

Pond 1 Charlotte 6-hr 2-yr 2 Year -Charlotte Rainfall=2.28"
Prepared by {enter your company name here} Page 26
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Subcatchment 2S: (Post Developed)
Runoff = 1.53 cfs @ 3.34 hrs, Volume= 0.088 af, Depth= 0.89"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-200.00 hrs, dt= 0.10 hrs
Charlotte 6-hr 2-yr 2 Year -Charlotte Rainfall=2.28"
Area (ac) CN Description
1.180 83
1.180 Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
17.6 Direct Entry,
Subcatchment 2S: (Post Developed)
Hydrograph
1.53 cfs
Charlotte 6-hr
2-yr; 2 Year -ICharl'otte
Rainfall=2.28"
Rkunoft Afea� 1-;fi80 -clo -
Runoff Volume=0.088 of
Runoff Depth=0.80"
Tc=17.& mi'�n
cN=83
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200
Time (hours)
— Runoff

Pond 1 Charlotte 6-hr 2-yr 2 Year -Charlotte Rainfall=2.28"
Prepared by (enter your company name here) Page 27
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Hydrograph for Subcatchment 2S: (Post Developed)
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
0.00
0.00
0.00
0.00
2.00
0.25
0.00
0.00
4.00
2.01
0.70
0.29
6.00
2.28
0.89
0.08
8.00
2.28
0.89
0.00
10.00
2.28
0.89
0.00
12.00
2.28
0.89
0.00
14.00
2.28
0.89
0.00
16.00
2.28
0.89
0.00
18.00
2.28
0.89
0.00
20.00
2.28
0.89
0.00
22.00
2.28
0.89
0.00
24.00
2.28
0.89
0.00
26.00
2.28
0.89
0.00
28.00
2.28
0.89
0.00
30.00
2.28
0.89
0.00
32.00
2.28
0.89
0.00
34.00
2.28
0.89
0.00
36.00
2.28
0.89
0.00
38.00
2.28
0.89
0.00
40.00
2.28
0.89
0.00
42.00
2.28
0.89
0.00
44.00
2.28
0.89
0.00
46.00
2.28
0.89
0.00
48.00
2.28
0.89
0.00
50.00
2.28
0.89
0.00
52.00
2.28
0.89
0.00
54.00
2.28
0.89
0.00
56.00
2.28
0.89
0.00
58.00
2.28
0.89
0.00
60.00
2.28
0.89
0.00
62.00
2.28
0.89
0.00
64.00
2.28
0.89
0.00
66.00
2.28
0.89
0.00
68.00
2.28
0.89
0.00
70.00
2.28
0.89
0.00
72.00
2.28
0.89
0.00
74.00
2.28
0.89
0.00
76.00
2.28
0.89
0.00
78.00
2.28
0.89
0.00
80.00
2.28
0.89
0.00
82.00
2.28
0.89
0.00
84.00
2.28
0.89
0.00
86.00
2.28
0.89
0.00
88.00
2.28
0.89
0.00
90.00
2.28
0.89
0.00
92.00
2.28
0.89
0.00
94.00
2.28
0.89
0.00
96.00
2.28
0.89
0.00
98.00
2.28
0.89
0.00
100.00
2.28
0.89
0.00
102.00
2.28
0.89
0.00
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
104.00
2.28
0.89
0.00
106.00
2.28
0.89
0.00
108.00
2.28
0.89
0.00
110.00
2.28
0.89
0.00
112.00
2.28
0.89
0.00
114.00
2.28
0.89
0.00
116.00
2.28
0.89
0.00
118.00
2.28
0.89
0.00
120.00
2.28
0.89
0.00
122.00
2.28
0.89
0.00
124.00
2.28
0.89
0.00
126.00
2.28
0.89
0.00
128.00
2.28
0.89
0.00
130.00
2.28
0.89
0.00
132.00
2.28
0.89
0.00
134.00
2.28
0.89
0.00
136.00
2.28
0.89
0.00
138.00
2.28
0.89
0.00
140.00
2.28
0.89
0.00
142.00
2.28
0.89
0.00
144.00
2.28
0.89
0.00
146.00
2.28
0.89
0.00
148.00
2.28
0.89
0.00
150.00
2.28
0.89
0.00
152.00
2.28
0.89
0.00
154.00
2.28
0.89
0.00
156.00
2.28
0.89
0.00
158.00
2.28
0.89
0.00
160.00
2.28
0.89
0.00
162.00
2.28
0.89
0.00
164.00
2.28
0.89
0.00
166.00
2.28
0.89
0.00
168.00
2.28
0.89
0.00
170.00
2.28
0.89
0.00
172.00
2.28
0.89
0.00
174.00
2.28
0.89
0.00
176.00
2.28
0.89
0.00
178.00
2.28
0.89
0.00
180.00
2.28
0.89
0.00
182.00
2.28
0.89
0.00
184.00
2.28
0.89
0.00
186.00
2.28
0.89
0.00
188.00
2.28
0.89
0.00
190.00
2.28
0.89
0.00
192.00
2.28
0.89
0.00
194.00
2.28
0.89
0.00
196.00
2.28
0.89
0.00
198.00
2.28
0.89
0.00
200.00
2.28
0.89
0.00

Pond 1 Charlotte 6-hr 2-yr 2 Year -Charlotte Rainfall=2.28"
Prepared by (enter your company name here) Page 28
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Pond 3P: (Sand Filter 1)
Inflow Area = 1.180 ac, Inflow Depth = 0.89" for 2 Year -Charlotte event
Inflow = 1.53 cfs @ 3.34 hrs, Volume= 0.088 of
Outflow = 0.37 cfs @ 3.88 hrs, Volume= 0.088 af, Atten= 76%, Lag= 32.6 min
Primary = 0.37 cfs @ 3.88 hrs, Volume= 0.088 of
Routing by Stor-Ind method, Time Span= 0.00-200.00 hrs, dt= 0.10 hrs
Peak Elev= 527.25' @ 3.88 hrs Surf.Area= 2,451 sf Storage= 2,250 cf
Plug -Flow detention time= 963.3 min calculated for 0.088 of (100% of inflow)
Center -of -Mass det. time= 963.1 min ( 1,193.7 - 230.6 )
Volume
Invert Avail.Storage Storage
Description
#1
526.00'
8,858 cf Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation
Surf.Area
Inc.Store
Cum.Store
(feet)
(sq-ft)
(cubic -feet)
(cubic -feet)
526.00
1,233
0
0
527.00
2,125
1,679
1,679
528.00
3,432
2,779
4,458
529.00
5,368
4,400
8,858
Device Routinq Invert Outlet Devices
#1 Primary
523.31'
15.0" x 62.0' long Culvert RCP, square edge headwall, Ke= 0.500
Outlet Invert= 523.00' S= 0.0050 '/' Cc= 0.900 n= 0.012
#2 Device 1
526.00'
Exfiltration
Head (feet) 0.00 1.00 2.00 3.00 4.00
Disch. (cfs) 0.000 0.013 0.018 0.023 0.028
#3 Device 1
527.00'
1.0' 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
#4 Device 1
528.00'
9.0' 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 Primary
528.00'
5.0' long x 10.0' 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) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64
Primary OutFlow Max=0.37 cfs @ 3.88 hrs HW=527.25' (Free Discharge)
1=Culvert (Passes 0.37 cfs of 10.32 cfs potential flow)
2=Exfiltration (Custom Controls 0.01 cfs)
3=Broad-Crested Rectangular Weir (Weir Controls 0.35 cfs @ 1.41 fps)
=Broad -Crested Rectangular Weir ( Controls 0.00 cfs)
= Broad-C rested Rectangular Weir ( Controls 0.00 cfs)

Pond 1
Charlotte 6-hr 2-yr 2 Year -Charlotte Rainfall=2.28"
Prepared by {enter your company name here} Page 29
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Pond 3P: (Sand Filter 1)
Hydrograph
1.53 cfs — Inflow
— Primary
Inflow Area-I11.180 a+c
Peaklll EIIllevll=52711625'
Storage=2,250 cf
y 1 I I I I I I I I I I I I I I I I I I
I I I I I I I I I I I I I I I I I I I
oI I I I I I I I I I I I I I I I I I I
LL
0.37 cfs
0
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200
Time (hours)

Pond 1 Charlotte 6-hr 2-yr 2 Year -Charlotte Rainfall=2.28"
Prepared by (enter your company name here) Page 30
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Hydrograph for Pond 3P: (Sand Filter 1)
Time
Inflow
Storage
Elevation
Primary
(hours)
(cfs)
(cubic -feet)
(feet)
(cfs)
0.00
0.00
0
526.00
0.00
5.00
0.12
1,992
527.14
0.16
10.00
0.00
1,582
526.95
0.01
15.00
0.00
1,371
526.85
0.01
20.00
0.00
1,184
526.75
0.01
25.00
0.00
1,018
526.67
0.01
30.00
0.00
872
526.58
0.01
35.00
0.00
744
526.51
0.01
40.00
0.00
633
526.44
0.01
45.00
0.00
536
526.38
0.00
50.00
0.00
453
526.33
0.00
55.00
0.00
382
526.28
0.00
60.00
0.00
321
526.24
0.00
65.00
0.00
270
526.20
0.00
70.00
0.00
226
526.17
0.00
75.00
0.00
189
526.15
0.00
80.00
0.00
157
526.12
0.00
85.00
0.00
131
526.10
0.00
90.00
0.00
109
526.09
0.00
95.00
0.00
91
526.07
0.00
100.00
0.00
75
526.06
0.00
105.00
0.00
63
526.05
0.00
110.00
0.00
52
526.04
0.00
115.00
0.00
43
526.03
0.00
120.00
0.00
36
526.03
0.00
125.00
0.00
30
526.02
0.00
130.00
0.00
25
526.02
0.00
135.00
0.00
20
526.02
0.00
140.00
0.00
17
526.01
0.00
145.00
0.00
14
526.01
0.00
150.00
0.00
12
526.01
0.00
155.00
0.00
10
526.01
0.00
160.00
0.00
8
526.01
0.00
165.00
0.00
7
526.01
0.00
170.00
0.00
6
526.00
0.00
175.00
0.00
5
526.00
0.00
180.00
0.00
4
526.00
0.00
185.00
0.00
3
526.00
0.00
190.00
0.00
3
526.00
0.00
195.00
0.00
2
526.00
0.00
200.00
0.00
2
526.00
0.00

Pond 1 Charlotte 6-hr 2-yr 2 Year -Charlotte Rainfall=2.28"
Prepared by (enter your company name here) Page 31
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Elevation Primary
(feet)
(cfs)
526.00
0.00
526.02
0.00
526.04
0.00
526.06
0.00
526.08
0.00
526.10
0.00
526.12
0.00
526.14
0.00
526.16
0.00
526.18
0.00
526.20
0.00
526.22
0.00
526.24
0.00
526.26
0.00
526.28
0.00
526.30
0.00
526.32
0.00
526.34
0.00
526.36
0.00
526.38
0.00
526.40
0.01
526.42
0.01
526.44
0.01
526.46
0.01
526.48
0.01
526.50
0.01
526.52
0.01
526.54
0.01
526.56
0.01
526.58
0.01
526.60
0.01
526.62
0.01
526.64
0.01
526.66
0.01
526.68
0.01
526.70
0.01
526.72
0.01
526.74
0.01
526.76
0.01
526.78
0.01
526.80
0.01
526.82
0.01
526.84
0.01
526.86
0.01
526.88
0.01
526.90
0.01
526.92
0.01
526.94
0.01
526.96
0.01
526.98
0.01
527.00
0.01
527.02
0.02
Stage -Discharge for Pond 3P: (Sand Filter 1)
Elevation Primary
(feet)
(cfs)
527.04
0.04
527.06
0.05
527.08
0.08
527.10
0.10
527.12
0.13
527.14
0.16
527.16
0.19
527.18
0.23
527.20
0.26
527.22
0.30
527.24
0.35
527.26
0.39
527.28
0.44
527.30
0.48
527.32
0.53
527.34
0.59
527.36
0.64
527.38
0.70
527.40
0.75
527.42
0.81
527.44
0.88
527.46
0.94
527.48
1.01
527.50
1.08
527.52
1.15
527.54
1.22
527.56
1.29
527.58
1.37
527.60
1.45
527.62
1.53
527.64
1.62
527.66
1.70
527.68
1.79
527.70
1.88
527.72
1.98
527.74
2.08
527.76
2.17
527.78
2.28
527.80
2.38
527.82
2.47
527.84
2.56
527.86
2.65
527.88
2.75
527.90
2.84
527.92
2.94
527.94
3.04
527.96
3.14
527.98
3.24
528.00
3.34
528.02
3.54
528.04
3.84
528.06
4.19
Elevation Primary
(feet)
(cfs)
528.08
4.60
528.10
5.04
528.12
5.52
528.14
6.03
528.16
6.58
528.18
7.15
528.20
7.75
528.22
8.39
528.24
9.06
528.26
9.76
528.28
10.49
528.30
11.24
528.32
12.03
528.34
12.83
528.36
13.66
528.38
14.52
528.40
15.38
528.42
15.67
528.44
15.97
528.46
16.28
528.48
16.60
528.50
16.93
528.52
17.27
528.54
17.61
528.56
17.97
528.58
18.33
528.60
18.70
528.62
19.04
528.64
19.39
528.66
19.74
528.68
20.10
528.70
20.46
528.72
20.83
528.74
21.20
528.76
21.57
528.78
21.95
528.80
22.33
528.82
22.72
528.84
23.11
528.86
23.51
528.88
23.91
528.90
24.31
528.92
24.72
528.94
25.13
528.96
25.54
528.98
25.96
529.00
26.39
529.02
26.82
529.04
27.26
529.06
27.71
529.08
28.16
529.10
28.61
Elevation Primary
(feet)
(cfs)
529.12
29.07
529.14
29.53
529.16
29.99
529.18
30.46
529.20
30.94
529.22
31.39
529.24
31.85
529.26
32.32
529.28
32.78
529.30
33.25
529.32
33.72
529.34
34.20
529.36
34.67
529.38
35.15
529.40
35.64
529.42
36.11
529.44
36.59
529.46
37.07
529.48
37.55
529.50
38.04
529.52
38.53
529.54
39.02
529.56
39.51
529.58
40.00
529.60
40.50
529.62
41.02
529.64
41.56
529.66
42.09
529.68
42.63
529.70
43.17
529.72
43.71
529.74
44.26
529.76
44.81
529.78
45.36
529.80
45.91
529.82
46.47
529.84
47.03
529.86
47.60
529.88
48.16
529.90
48.73
529.92
49.31
529.94
49.88
529.96
50.46
529.98
51.04
530.00
51.62

Pond 1 Charlotte 6-hr 2-yr 2 Year -Charlotte Rainfall=2.28"
Prepared by (enter your company name here) Page 32
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Stage -Area -Storage for Pond 3P: (Sand Filter 1)
Elevation
Surface
Storage
(feet)
(sq-ft)
(cubic -feet)
526.00
1,233
0
526.05
1,278
63
526.10
1,322
128
526.15
1,367
195
526.20
1,411
264
526.25
1,456
336
526.30
1,501
410
526.35
1,545
486
526.40
1,590
565
526.45
1,634
645
526.50
1,679
728
526.55
1,724
813
526.60
1,768
900
526.65
1,813
990
526.70
1,857
1,082
526.75
1,902
1,176
526.80
1,947
1,272
526.85
1,991
1,370
526.90
2,036
1,471
526.95
2,080
1,574
527.00
2,125
1,679
527.05
2,190
1,787
527.10
2,256
1,898
527.15
2,321
2,012
527.20
2,386
2,130
527.25
2,452
2,251
527.30
2,517
2,375
527.35
2,582
2,503
527.40
2,648
2,634
527.45
2,713
2,768
527.50
2,779
2,905
527.55
2,844
3,045
527.60
2,909
3,189
527.65
2,975
3,336
527.70
3,040
3,487
527.75
3,105
3,640
527.80
3,171
3,797
527.85
3,236
3,957
527.90
3,301
4,121
527.95
3,367
4,288
528.00
3,432
4,458
528.05
3,529
4,632
528.10
3,626
4,810
528.15
3,722
4,994
528.20
3,819
5,183
528.25
3,916
5,376
528.30
4,013
5,574
528.35
4,110
5,777
528.40
4,206
5,985
528.45
4,303
6,198
528.50
4,400
6,416
528.55
4,497
6,638
Elevation
Surface
Storage
(feet)
(sq-ft)
(cubic -feet)
528.60
4,594
6,865
528.65
4,690
7,097
528.70
4,787
7,334
528.75
4,884
7,576
528.80
4,981
7,823
528.85
5,078
8,074
528.90
5,174
8,330
528.95
5,271
8,592
529.00
5,368
8,858
529.05
5,368
8,858
529.10
5,368
8,858
529.15
5,368
8,858
529.20
5,368
8,858
529.25
5,368
8,858
529.30
5,368
8,858
529.35
5,368
8,858
529.40
5,368
8,858
529.45
5,368
8,858
529.50
5,368
8,858
529.55
5,368
8,858
529.60
5,368
8,858
529.65
5,368
8,858
529.70
5,368
8,858
529.75
5,368
8,858
529.80
5,368
8,858
529.85
5,368
8,858
529.90
5,368
8,858
529.95
5,368
8,858
530.00
5,368
8,858

Pond 1 Charlotte 6-hr 10-yr 10 Year -Charlotte Rainfall=3.72"
Prepared by (enter your company name here) Page 33
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Time span =0.00-200.00 hrs, dt=0.10 hrs, 2001 points
Runoff by SCS TR-20 method, UH=SCS
Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method
Subcatchment 1S: (Predeveloped) Runoff Area=1.180 ac Runoff Depth=1.46"
Tc=18.4 min CN=75 Runoff=2.26 cfs 0.144 of
Subcatchment 2S: (Post Developed) Runoff Area=1.180 ac Runoff Depth=2.05"
Tc=17.6 min CN=83 Runoff=3.34 cfs 0.201 of
Pond 3P: (Sand Filter 1) Peak Elev=527.72' Storage=3,534 cf Inflow=3.34 cfs 0.201 of
Outflow=1.96 cfs 0.201 of
Total Runoff Area = 2.360 ac Runoff Volume = 0.345 of Average Runoff Depth = 1.75"
100.00% Pervious Area = 2.360 ac 0.00% Impervious Area = 0.000 ac

Pond 1 Charlotte 6-hr 10-yr 10 Year -Charlotte Rainfall=3.72"
Prepared by {enter your company name here} Page 34
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Subcatchment 1 S: (Predeveloped)
Runoff = 2.26 cfs @ 3.35 hrs, Volume= 0.144 af, Depth= 1.46"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-200.00 hrs, dt= 0.10 hrs
Charlotte 6-hr 10-yr 10 Year -Charlotte Rainfall=3.72"
Area (ac) CN Description
1.180 75 See Calculations
1.180 Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
18.4 Direct Entry,
Subcatchment 1 S: (Predeveloped)
Hydrograph
2.26 cfs
Charlotte 6-hr 10-yr 10 Year -Charlotte
2-L---L------L------L------L---1---L------1---1---1---I_ 1-Rainfail=34T'
Runoff Area=11.1801 ac
Runoff Volume=Q.144 of
Runoff Depth=1.46"
Tc=18.4 rihin
CN=75
1-J___L___I---L___I---L___I---L___I---L___I---L---I---L---I---L---I---L---I---
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200
Time (hours)
— Runoff

Pond 1 Charlotte 6-hr 10-yr 10 Year -Charlotte Rainfall=3.72"
Prepared by (enter your company name here) Page 35
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Hydrograph for Subcatchment 1S: (Predeveloped)
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
0.00
0.00
0.00
0.00
2.00
0.39
0.00
0.00
4.00
3.29
1.16
0.51
6.00
3.72
1.46
0.13
8.00
3.72
1.46
0.00
10.00
3.72
1.46
0.00
12.00
3.72
1.46
0.00
14.00
3.72
1.46
0.00
16.00
3.72
1.46
0.00
18.00
3.72
1.46
0.00
20.00
3.72
1.46
0.00
22.00
3.72
1.46
0.00
24.00
3.72
1.46
0.00
26.00
3.72
1.46
0.00
28.00
3.72
1.46
0.00
30.00
3.72
1.46
0.00
32.00
3.72
1.46
0.00
34.00
3.72
1.46
0.00
36.00
3.72
1.46
0.00
38.00
3.72
1.46
0.00
40.00
3.72
1.46
0.00
42.00
3.72
1.46
0.00
44.00
3.72
1.46
0.00
46.00
3.72
1.46
0.00
48.00
3.72
1.46
0.00
50.00
3.72
1.46
0.00
52.00
3.72
1.46
0.00
54.00
3.72
1.46
0.00
56.00
3.72
1.46
0.00
58.00
3.72
1.46
0.00
60.00
3.72
1.46
0.00
62.00
3.72
1.46
0.00
64.00
3.72
1.46
0.00
66.00
3.72
1.46
0.00
68.00
3.72
1.46
0.00
70.00
3.72
1.46
0.00
72.00
3.72
1.46
0.00
74.00
3.72
1.46
0.00
76.00
3.72
1.46
0.00
78.00
3.72
1.46
0.00
80.00
3.72
1.46
0.00
82.00
3.72
1.46
0.00
84.00
3.72
1.46
0.00
86.00
3.72
1.46
0.00
88.00
3.72
1.46
0.00
90.00
3.72
1.46
0.00
92.00
3.72
1.46
0.00
94.00
3.72
1.46
0.00
96.00
3.72
1.46
0.00
98.00
3.72
1.46
0.00
100.00
3.72
1.46
0.00
102.00
3.72
1.46
0.00
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
104.00
3.72
1.46
0.00
106.00
3.72
1.46
0.00
108.00
3.72
1.46
0.00
110.00
3.72
1.46
0.00
112.00
3.72
1.46
0.00
114.00
3.72
1.46
0.00
116.00
3.72
1.46
0.00
118.00
3.72
1.46
0.00
120.00
3.72
1.46
0.00
122.00
3.72
1.46
0.00
124.00
3.72
1.46
0.00
126.00
3.72
1.46
0.00
128.00
3.72
1.46
0.00
130.00
3.72
1.46
0.00
132.00
3.72
1.46
0.00
134.00
3.72
1.46
0.00
136.00
3.72
1.46
0.00
138.00
3.72
1.46
0.00
140.00
3.72
1.46
0.00
142.00
3.72
1.46
0.00
144.00
3.72
1.46
0.00
146.00
3.72
1.46
0.00
148.00
3.72
1.46
0.00
150.00
3.72
1.46
0.00
152.00
3.72
1.46
0.00
154.00
3.72
1.46
0.00
156.00
3.72
1.46
0.00
158.00
3.72
1.46
0.00
160.00
3.72
1.46
0.00
162.00
3.72
1.46
0.00
164.00
3.72
1.46
0.00
166.00
3.72
1.46
0.00
168.00
3.72
1.46
0.00
170.00
3.72
1.46
0.00
172.00
3.72
1.46
0.00
174.00
3.72
1.46
0.00
176.00
3.72
1.46
0.00
178.00
3.72
1.46
0.00
180.00
3.72
1.46
0.00
182.00
3.72
1.46
0.00
184.00
3.72
1.46
0.00
186.00
3.72
1.46
0.00
188.00
3.72
1.46
0.00
190.00
3.72
1.46
0.00
192.00
3.72
1.46
0.00
194.00
3.72
1.46
0.00
196.00
3.72
1.46
0.00
198.00
3.72
1.46
0.00
200.00
3.72
1.46
0.00

Pond 1 Charlotte 6-hr 10-yr 10 Year -Charlotte Rainfall=3.72"
Prepared by {enter your company name here} Page 36
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Subcatchment 2S: (Post Developed)
Runoff = 3.34 cfs @ 3.33 hrs, Volume= 0.201 af, Depth= 2.05"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-200.00 hrs, dt= 0.10 hrs
Charlotte 6-hr 10-yr 10 Year -Charlotte Rainfall=3.72"
Area (ac) CN Description
1.180 83
1.180 Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
17.6 Direct Entry,
Subcatchment 2S: (Post Developed)
Hydrograph
3.34 cfs
Charlotte 6-hr 10-yr 10 Year -Charlotte
s-;---r------r------ r------ r------ r------t--- ---rt-- rt-Rafnfail_3.�T'
Runoff Area=1�.180 ac
Runoff Volume=Q.201 of
Runoff Depth=2.05"
Tc=11.6 rihin
2--------------------------' -- -- --T -- --- CN=S3-
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200
Time (hours)
— Runoff

Pond 1 Charlotte 6-hr 10-yr 10 Year -Charlotte Rainfall=3.72"
Prepared by (enter your company name here) Page 37
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Hydrograph for Subcatchment 2S: (Post Developed)
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
0.00
0.00
0.00
0.00
2.00
0.39
0.00
0.00
4.00
3.29
1.68
0.61
6.00
3.72
2.05
0.15
8.00
3.72
2.05
0.00
10.00
3.72
2.05
0.00
12.00
3.72
2.05
0.00
14.00
3.72
2.05
0.00
16.00
3.72
2.05
0.00
18.00
3.72
2.05
0.00
20.00
3.72
2.05
0.00
22.00
3.72
2.05
0.00
24.00
3.72
2.05
0.00
26.00
3.72
2.05
0.00
28.00
3.72
2.05
0.00
30.00
3.72
2.05
0.00
32.00
3.72
2.05
0.00
34.00
3.72
2.05
0.00
36.00
3.72
2.05
0.00
38.00
3.72
2.05
0.00
40.00
3.72
2.05
0.00
42.00
3.72
2.05
0.00
44.00
3.72
2.05
0.00
46.00
3.72
2.05
0.00
48.00
3.72
2.05
0.00
50.00
3.72
2.05
0.00
52.00
3.72
2.05
0.00
54.00
3.72
2.05
0.00
56.00
3.72
2.05
0.00
58.00
3.72
2.05
0.00
60.00
3.72
2.05
0.00
62.00
3.72
2.05
0.00
64.00
3.72
2.05
0.00
66.00
3.72
2.05
0.00
68.00
3.72
2.05
0.00
70.00
3.72
2.05
0.00
72.00
3.72
2.05
0.00
74.00
3.72
2.05
0.00
76.00
3.72
2.05
0.00
78.00
3.72
2.05
0.00
80.00
3.72
2.05
0.00
82.00
3.72
2.05
0.00
84.00
3.72
2.05
0.00
86.00
3.72
2.05
0.00
88.00
3.72
2.05
0.00
90.00
3.72
2.05
0.00
92.00
3.72
2.05
0.00
94.00
3.72
2.05
0.00
96.00
3.72
2.05
0.00
98.00
3.72
2.05
0.00
100.00
3.72
2.05
0.00
102.00
3.72
2.05
0.00
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
104.00
3.72
2.05
0.00
106.00
3.72
2.05
0.00
108.00
3.72
2.05
0.00
110.00
3.72
2.05
0.00
112.00
3.72
2.05
0.00
114.00
3.72
2.05
0.00
116.00
3.72
2.05
0.00
118.00
3.72
2.05
0.00
120.00
3.72
2.05
0.00
122.00
3.72
2.05
0.00
124.00
3.72
2.05
0.00
126.00
3.72
2.05
0.00
128.00
3.72
2.05
0.00
130.00
3.72
2.05
0.00
132.00
3.72
2.05
0.00
134.00
3.72
2.05
0.00
136.00
3.72
2.05
0.00
138.00
3.72
2.05
0.00
140.00
3.72
2.05
0.00
142.00
3.72
2.05
0.00
144.00
3.72
2.05
0.00
146.00
3.72
2.05
0.00
148.00
3.72
2.05
0.00
150.00
3.72
2.05
0.00
152.00
3.72
2.05
0.00
154.00
3.72
2.05
0.00
156.00
3.72
2.05
0.00
158.00
3.72
2.05
0.00
160.00
3.72
2.05
0.00
162.00
3.72
2.05
0.00
164.00
3.72
2.05
0.00
166.00
3.72
2.05
0.00
168.00
3.72
2.05
0.00
170.00
3.72
2.05
0.00
172.00
3.72
2.05
0.00
174.00
3.72
2.05
0.00
176.00
3.72
2.05
0.00
178.00
3.72
2.05
0.00
180.00
3.72
2.05
0.00
182.00
3.72
2.05
0.00
184.00
3.72
2.05
0.00
186.00
3.72
2.05
0.00
188.00
3.72
2.05
0.00
190.00
3.72
2.05
0.00
192.00
3.72
2.05
0.00
194.00
3.72
2.05
0.00
196.00
3.72
2.05
0.00
198.00
3.72
2.05
0.00
200.00
3.72
2.05
0.00

Pond 1 Charlotte 6-hr 10-yr 10 Year -Charlotte Rainfall=3.72"
Prepared by (enter your company name here) Page 38
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Pond 3P: (Sand Filter 1)
Inflow Area = 1.180 ac, Inflow Depth = 2.05" for 10 Year -Charlotte event
Inflow = 3.34 cfs @ 3.33 hrs, Volume= 0.201 of
Outflow = 1.96 cfs @ 3.55 hrs, Volume= 0.201 af, Atten= 41 %, Lag= 13.6 min
Primary = 1.96 cfs @ 3.55 hrs, Volume= 0.201 of
Routing by Stor-Ind method, Time Span= 0.00-200.00 hrs, dt= 0.10 hrs
Peak Elev= 527.72' @ 3.55 hrs Surf.Area= 3,060 sf Storage= 3,534 cf
Plug -Flow detention time= 435.8 min calculated for 0.201 of (100% of inflow)
Center -of -Mass det. time= 435.7 min ( 659.9 - 224.2 )
Volume
Invert Avail.Storage Storage
Description
#1
526.00'
8,858 cf Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation
Surf.Area
Inc.Store
Cum.Store
(feet)
(sq-ft)
(cubic -feet)
(cubic -feet)
526.00
1,233
0
0
527.00
2,125
1,679
1,679
528.00
3,432
2,779
4,458
529.00
5,368
4,400
8,858
Device Routinq Invert Outlet Devices
#1 Primary
523.31'
15.0" x 62.0' long Culvert RCP, square edge headwall, Ke= 0.500
Outlet Invert= 523.00' S= 0.0050 '/' Cc= 0.900 n= 0.012
#2 Device 1
526.00'
Exfiltration
Head (feet) 0.00 1.00 2.00 3.00 4.00
Disch. (cfs) 0.000 0.013 0.018 0.023 0.028
#3 Device 1
527.00'
1.0' 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
#4 Device 1
528.00'
9.0' 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 Primary
528.00'
5.0' long x 10.0' 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) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64
Primary OutFlow Max=1.93 cfs @ 3.55 hrs HW=527.71' (Free Discharge)
1=Culvert (Passes 1.93 cfs of 11.08 cfs potential flow)
2=Exfiltration (Custom Controls 0.02 cfs)
3=Broad-Crested Rectangular Weir (Weir Controls 1.91 cfs @ 2.70 fps)
=Broad -Crested Rectangular Weir ( Controls 0.00 cfs)
= Broad-C rested Rectangular Weir ( Controls 0.00 cfs)

Pond 1
Charlotte 6-hr 10-yr 10 Year -Charlotte Rainfall=3.72"
Prepared by {enter your company name here} Page 39
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Pond 3P: (Sand Filter 1)
Hydrograph
3.34 ofs — Inflow
— Primary
Inflow_Area-1_.180 a+c__
1-r---r--r---r--r---r--r---r--r---r--r---r- r -i --r- r r
Peak��� Elev=527672'
Storage=3,534 cf
1.96 cfs
1
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200
Time (hours)

Pond 1 Charlotte 6-hr 10-yr 10 Year -Charlotte Rainfall=3.72"
Prepared by (enter your company name here) Page 40
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Hydrograph for Pond 3P: (Sand Filter 1)
Time
Inflow
Storage
Elevation
Primary
(hours)
(cfs)
(cubic -feet)
(feet)
(cfs)
0.00
0.00
0
526.00
0.00
5.00
0.22
2,174
527.22
0.30
10.00
0.00
1,594
526.96
0.01
15.00
0.00
1,382
526.86
0.01
20.00
0.00
1,193
526.76
0.01
25.00
0.00
1,026
526.67
0.01
30.00
0.00
879
526.59
0.01
35.00
0.00
750
526.51
0.01
40.00
0.00
638
526.45
0.01
45.00
0.00
541
526.39
0.01
50.00
0.00
457
526.33
0.00
55.00
0.00
386
526.28
0.00
60.00
0.00
324
526.24
0.00
65.00
0.00
272
526.21
0.00
70.00
0.00
228
526.17
0.00
75.00
0.00
190
526.15
0.00
80.00
0.00
159
526.12
0.00
85.00
0.00
132
526.10
0.00
90.00
0.00
110
526.09
0.00
95.00
0.00
92
526.07
0.00
100.00
0.00
76
526.06
0.00
105.00
0.00
63
526.05
0.00
110.00
0.00
53
526.04
0.00
115.00
0.00
44
526.03
0.00
120.00
0.00
36
526.03
0.00
125.00
0.00
30
526.02
0.00
130.00
0.00
25
526.02
0.00
135.00
0.00
21
526.02
0.00
140.00
0.00
17
526.01
0.00
145.00
0.00
14
526.01
0.00
150.00
0.00
12
526.01
0.00
155.00
0.00
10
526.01
0.00
160.00
0.00
8
526.01
0.00
165.00
0.00
7
526.01
0.00
170.00
0.00
6
526.00
0.00
175.00
0.00
5
526.00
0.00
180.00
0.00
4
526.00
0.00
185.00
0.00
3
526.00
0.00
190.00
0.00
3
526.00
0.00
195.00
0.00
2
526.00
0.00
200.00
0.00
2
526.00
0.00

Pond 1 Charlotte 6-hr 10-yr 10 Year -Charlotte Rainfall=3.72"
Prepared by (enter your company name here) Page 41
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Elevation Primary
(feet)
(cfs)
526.00
0.00
526.02
0.00
526.04
0.00
526.06
0.00
526.08
0.00
526.10
0.00
526.12
0.00
526.14
0.00
526.16
0.00
526.18
0.00
526.20
0.00
526.22
0.00
526.24
0.00
526.26
0.00
526.28
0.00
526.30
0.00
526.32
0.00
526.34
0.00
526.36
0.00
526.38
0.00
526.40
0.01
526.42
0.01
526.44
0.01
526.46
0.01
526.48
0.01
526.50
0.01
526.52
0.01
526.54
0.01
526.56
0.01
526.58
0.01
526.60
0.01
526.62
0.01
526.64
0.01
526.66
0.01
526.68
0.01
526.70
0.01
526.72
0.01
526.74
0.01
526.76
0.01
526.78
0.01
526.80
0.01
526.82
0.01
526.84
0.01
526.86
0.01
526.88
0.01
526.90
0.01
526.92
0.01
526.94
0.01
526.96
0.01
526.98
0.01
527.00
0.01
527.02
0.02
Stage -Discharge for Pond 3P: (Sand Filter 1)
Elevation Primary
(feet)
(cfs)
527.04
0.04
527.06
0.05
527.08
0.08
527.10
0.10
527.12
0.13
527.14
0.16
527.16
0.19
527.18
0.23
527.20
0.26
527.22
0.30
527.24
0.35
527.26
0.39
527.28
0.44
527.30
0.48
527.32
0.53
527.34
0.59
527.36
0.64
527.38
0.70
527.40
0.75
527.42
0.81
527.44
0.88
527.46
0.94
527.48
1.01
527.50
1.08
527.52
1.15
527.54
1.22
527.56
1.29
527.58
1.37
527.60
1.45
527.62
1.53
527.64
1.62
527.66
1.70
527.68
1.79
527.70
1.88
527.72
1.98
527.74
2.08
527.76
2.17
527.78
2.28
527.80
2.38
527.82
2.47
527.84
2.56
527.86
2.65
527.88
2.75
527.90
2.84
527.92
2.94
527.94
3.04
527.96
3.14
527.98
3.24
528.00
3.34
528.02
3.54
528.04
3.84
528.06
4.19
Elevation Primary
(feet)
(cfs)
528.08
4.60
528.10
5.04
528.12
5.52
528.14
6.03
528.16
6.58
528.18
7.15
528.20
7.75
528.22
8.39
528.24
9.06
528.26
9.76
528.28
10.49
528.30
11.24
528.32
12.03
528.34
12.83
528.36
13.66
528.38
14.52
528.40
15.38
528.42
15.67
528.44
15.97
528.46
16.28
528.48
16.60
528.50
16.93
528.52
17.27
528.54
17.61
528.56
17.97
528.58
18.33
528.60
18.70
528.62
19.04
528.64
19.39
528.66
19.74
528.68
20.10
528.70
20.46
528.72
20.83
528.74
21.20
528.76
21.57
528.78
21.95
528.80
22.33
528.82
22.72
528.84
23.11
528.86
23.51
528.88
23.91
528.90
24.31
528.92
24.72
528.94
25.13
528.96
25.54
528.98
25.96
529.00
26.39
529.02
26.82
529.04
27.26
529.06
27.71
529.08
28.16
529.10
28.61
Elevation Primary
(feet)
(cfs)
529.12
29.07
529.14
29.53
529.16
29.99
529.18
30.46
529.20
30.94
529.22
31.39
529.24
31.85
529.26
32.32
529.28
32.78
529.30
33.25
529.32
33.72
529.34
34.20
529.36
34.67
529.38
35.15
529.40
35.64
529.42
36.11
529.44
36.59
529.46
37.07
529.48
37.55
529.50
38.04
529.52
38.53
529.54
39.02
529.56
39.51
529.58
40.00
529.60
40.50
529.62
41.02
529.64
41.56
529.66
42.09
529.68
42.63
529.70
43.17
529.72
43.71
529.74
44.26
529.76
44.81
529.78
45.36
529.80
45.91
529.82
46.47
529.84
47.03
529.86
47.60
529.88
48.16
529.90
48.73
529.92
49.31
529.94
49.88
529.96
50.46
529.98
51.04
530.00
51.62

Pond 1 Charlotte 6-hr 10-yr 10 Year -Charlotte Rainfall=3.72"
Prepared by (enter your company name here) Page 42
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Stage -Area -Storage for Pond 3P: (Sand Filter 1)
Elevation
Surface
Storage
(feet)
(sq-ft)
(cubic -feet)
526.00
1,233
0
526.05
1,278
63
526.10
1,322
128
526.15
1,367
195
526.20
1,411
264
526.25
1,456
336
526.30
1,501
410
526.35
1,545
486
526.40
1,590
565
526.45
1,634
645
526.50
1,679
728
526.55
1,724
813
526.60
1,768
900
526.65
1,813
990
526.70
1,857
1,082
526.75
1,902
1,176
526.80
1,947
1,272
526.85
1,991
1,370
526.90
2,036
1,471
526.95
2,080
1,574
527.00
2,125
1,679
527.05
2,190
1,787
527.10
2,256
1,898
527.15
2,321
2,012
527.20
2,386
2,130
527.25
2,452
2,251
527.30
2,517
2,375
527.35
2,582
2,503
527.40
2,648
2,634
527.45
2,713
2,768
527.50
2,779
2,905
527.55
2,844
3,045
527.60
2,909
3,189
527.65
2,975
3,336
527.70
3,040
3,487
527.75
3,105
3,640
527.80
3,171
3,797
527.85
3,236
3,957
527.90
3,301
4,121
527.95
3,367
4,288
528.00
3,432
4,458
528.05
3,529
4,632
528.10
3,626
4,810
528.15
3,722
4,994
528.20
3,819
5,183
528.25
3,916
5,376
528.30
4,013
5,574
528.35
4,110
5,777
528.40
4,206
5,985
528.45
4,303
6,198
528.50
4,400
6,416
528.55
4,497
6,638
Elevation
Surface
Storage
(feet)
(sq-ft)
(cubic -feet)
528.60
4,594
6,865
528.65
4,690
7,097
528.70
4,787
7,334
528.75
4,884
7,576
528.80
4,981
7,823
528.85
5,078
8,074
528.90
5,174
8,330
528.95
5,271
8,592
529.00
5,368
8,858
529.05
5,368
8,858
529.10
5,368
8,858
529.15
5,368
8,858
529.20
5,368
8,858
529.25
5,368
8,858
529.30
5,368
8,858
529.35
5,368
8,858
529.40
5,368
8,858
529.45
5,368
8,858
529.50
5,368
8,858
529.55
5,368
8,858
529.60
5,368
8,858
529.65
5,368
8,858
529.70
5,368
8,858
529.75
5,368
8,858
529.80
5,368
8,858
529.85
5,368
8,858
529.90
5,368
8,858
529.95
5,368
8,858
530.00
5,368
8,858

Pond 1 Charlotte 6-hr 25-yr 25 Year -Charlotte Rainfall=4.38"
Prepared by (enter your company name here) Page 43
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Time span =0.00-200.00 hrs, dt=0.10 hrs, 2001 points
Runoff by SCS TR-20 method, UH=SCS
Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method
Subcatchment 1S: (Predeveloped) Runoff Area=1.180 ac Runoff Depth=1.96"
Tc=18.4 min CN=75 Runoff=3.07 cfs 0.192 of
Subcatchment 2S: (Post Developed) Runoff Area=1.180 ac Runoff Depth=2.62"
Tc=17.6 min CN=83 Runoff=4.22 cfs 0.258 of
Pond 3P: (Sand Filter 1) Peak Elev=527.89' Storage=4,087 cf Inflow=4.22 cfs 0.258 of
Outflow=2.79 cfs 0.258 of
Total Runoff Area = 2.360 ac Runoff Volume = 0.450 of Average Runoff Depth = 2.29"
100.00% Pervious Area = 2.360 ac 0.00% Impervious Area = 0.000 ac

Pond 1 Charlotte 6-hr 25-yr 25 Year -Charlotte Rainfall=4.38"
Prepared by {enter your company name here} Page 44
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Subcatchment 1 S: (Predeveloped)
Runoff = 3.07 cfs @ 3.34 hrs, Volume= 0.192 af, Depth= 1.96"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-200.00 hrs, dt= 0.10 hrs
Charlotte 6-hr 25-yr 25 Year -Charlotte Rainfall=4.38"
Area (ac) CN Description
1.180 75 See Calculations
1.180 Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
18.4 Direct Entry,
Subcatchment 1 S: (Predeveloped)
Hydrograph
3.07 cfs
s Charlotte 6-hr 25-y'r 25� Year -Charlotte
Rainfall=4.�8"
Runoff Area=1�.180� ac
Runoff Volume=Q.192 of
Runoff Qepth=1.96"
2 - ---------T------ T------T------T------T--- I - - - T--- ---T-- Tc=18A riilm
CN=75
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200
Time (hours)
— Runoff

Pond 1 Charlotte 6-hr 25-yr 25 Year -Charlotte Rainfall=4.38"
Prepared by (enter your company name here) Page 45
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Hydrograph for Subcatchment 1S: (Predeveloped)
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
0.00
0.00
0.00
0.00
2.00
0.48
0.00
0.00
4.00
3.87
1.57
0.66
6.00
4.38
1.96
0.17
8.00
4.38
1.96
0.00
10.00
4.38
1.96
0.00
12.00
4.38
1.96
0.00
14.00
4.38
1.96
0.00
16.00
4.38
1.96
0.00
18.00
4.38
1.96
0.00
20.00
4.38
1.96
0.00
22.00
4.38
1.96
0.00
24.00
4.38
1.96
0.00
26.00
4.38
1.96
0.00
28.00
4.38
1.96
0.00
30.00
4.38
1.96
0.00
32.00
4.38
1.96
0.00
34.00
4.38
1.96
0.00
36.00
4.38
1.96
0.00
38.00
4.38
1.96
0.00
40.00
4.38
1.96
0.00
42.00
4.38
1.96
0.00
44.00
4.38
1.96
0.00
46.00
4.38
1.96
0.00
48.00
4.38
1.96
0.00
50.00
4.38
1.96
0.00
52.00
4.38
1.96
0.00
54.00
4.38
1.96
0.00
56.00
4.38
1.96
0.00
58.00
4.38
1.96
0.00
60.00
4.38
1.96
0.00
62.00
4.38
1.96
0.00
64.00
4.38
1.96
0.00
66.00
4.38
1.96
0.00
68.00
4.38
1.96
0.00
70.00
4.38
1.96
0.00
72.00
4.38
1.96
0.00
74.00
4.38
1.96
0.00
76.00
4.38
1.96
0.00
78.00
4.38
1.96
0.00
80.00
4.38
1.96
0.00
82.00
4.38
1.96
0.00
84.00
4.38
1.96
0.00
86.00
4.38
1.96
0.00
88.00
4.38
1.96
0.00
90.00
4.38
1.96
0.00
92.00
4.38
1.96
0.00
94.00
4.38
1.96
0.00
96.00
4.38
1.96
0.00
98.00
4.38
1.96
0.00
100.00
4.38
1.96
0.00
102.00
4.38
1.96
0.00
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
104.00
4.38
1.96
0.00
106.00
4.38
1.96
0.00
108.00
4.38
1.96
0.00
110.00
4.38
1.96
0.00
112.00
4.38
1.96
0.00
114.00
4.38
1.96
0.00
116.00
4.38
1.96
0.00
118.00
4.38
1.96
0.00
120.00
4.38
1.96
0.00
122.00
4.38
1.96
0.00
124.00
4.38
1.96
0.00
126.00
4.38
1.96
0.00
128.00
4.38
1.96
0.00
130.00
4.38
1.96
0.00
132.00
4.38
1.96
0.00
134.00
4.38
1.96
0.00
136.00
4.38
1.96
0.00
138.00
4.38
1.96
0.00
140.00
4.38
1.96
0.00
142.00
4.38
1.96
0.00
144.00
4.38
1.96
0.00
146.00
4.38
1.96
0.00
148.00
4.38
1.96
0.00
150.00
4.38
1.96
0.00
152.00
4.38
1.96
0.00
154.00
4.38
1.96
0.00
156.00
4.38
1.96
0.00
158.00
4.38
1.96
0.00
160.00
4.38
1.96
0.00
162.00
4.38
1.96
0.00
164.00
4.38
1.96
0.00
166.00
4.38
1.96
0.00
168.00
4.38
1.96
0.00
170.00
4.38
1.96
0.00
172.00
4.38
1.96
0.00
174.00
4.38
1.96
0.00
176.00
4.38
1.96
0.00
178.00
4.38
1.96
0.00
180.00
4.38
1.96
0.00
182.00
4.38
1.96
0.00
184.00
4.38
1.96
0.00
186.00
4.38
1.96
0.00
188.00
4.38
1.96
0.00
190.00
4.38
1.96
0.00
192.00
4.38
1.96
0.00
194.00
4.38
1.96
0.00
196.00
4.38
1.96
0.00
198.00
4.38
1.96
0.00
200.00
4.38
1.96
0.00

Pond 1 Charlotte 6-hr 25-yr 25 Year -Charlotte Rainfall=4.38"
Prepared by {enter your company name here} Page 46
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Subcatchment 2S: (Post Developed)
Runoff = 4.22 cfs @ 3.32 hrs, Volume= 0.258 af, Depth= 2.62"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-200.00 hrs, dt= 0.10 hrs
Charlotte 6-hr 25-yr 25 Year -Charlotte Rainfall=4.38"
Area (ac) CN Description
1.180 83
1.180 Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
17.6 Direct Entry,
Subcatchment 2S: (Post Developed)
Hydrograph
4.22 cfs
4-+---+---1---+---1---+---1---+---1---+--- herlotte-&hr25-err-2,1�Year -Charlottes-
1 I Rainfall=4.�8"
Runoff Area=l�.180� ac
Runoff Volume=9.258 of
s--------------------------'---- - -- -Runoff Depth=2.62"-
Tc=117.6 rbin
CN=83
1--I---i---I---i---I---+ i - - -i-- -I--- + - - -I--- + - - -I---T - - -I---T - - -
I
--- ---I---
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200
Time (hours)
— Runoff

Pond 1 Charlotte 6-hr 25-yr 25 Year -Charlotte Rainfall=4.38"
Prepared by (enter your company name here) Page 47
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Hydrograph for Subcatchment 2S: (Post Developed)
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
0.00
0.00
0.00
0.00
2.00
0.48
0.00
0.00
4.00
3.87
2.17
0.76
6.00
4.38
2.62
0.19
8.00
4.38
2.62
0.00
10.00
4.38
2.62
0.00
12.00
4.38
2.62
0.00
14.00
4.38
2.62
0.00
16.00
4.38
2.62
0.00
18.00
4.38
2.62
0.00
20.00
4.38
2.62
0.00
22.00
4.38
2.62
0.00
24.00
4.38
2.62
0.00
26.00
4.38
2.62
0.00
28.00
4.38
2.62
0.00
30.00
4.38
2.62
0.00
32.00
4.38
2.62
0.00
34.00
4.38
2.62
0.00
36.00
4.38
2.62
0.00
38.00
4.38
2.62
0.00
40.00
4.38
2.62
0.00
42.00
4.38
2.62
0.00
44.00
4.38
2.62
0.00
46.00
4.38
2.62
0.00
48.00
4.38
2.62
0.00
50.00
4.38
2.62
0.00
52.00
4.38
2.62
0.00
54.00
4.38
2.62
0.00
56.00
4.38
2.62
0.00
58.00
4.38
2.62
0.00
60.00
4.38
2.62
0.00
62.00
4.38
2.62
0.00
64.00
4.38
2.62
0.00
66.00
4.38
2.62
0.00
68.00
4.38
2.62
0.00
70.00
4.38
2.62
0.00
72.00
4.38
2.62
0.00
74.00
4.38
2.62
0.00
76.00
4.38
2.62
0.00
78.00
4.38
2.62
0.00
80.00
4.38
2.62
0.00
82.00
4.38
2.62
0.00
84.00
4.38
2.62
0.00
86.00
4.38
2.62
0.00
88.00
4.38
2.62
0.00
90.00
4.38
2.62
0.00
92.00
4.38
2.62
0.00
94.00
4.38
2.62
0.00
96.00
4.38
2.62
0.00
98.00
4.38
2.62
0.00
100.00
4.38
2.62
0.00
102.00
4.38
2.62
0.00
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
104.00
4.38
2.62
0.00
106.00
4.38
2.62
0.00
108.00
4.38
2.62
0.00
110.00
4.38
2.62
0.00
112.00
4.38
2.62
0.00
114.00
4.38
2.62
0.00
116.00
4.38
2.62
0.00
118.00
4.38
2.62
0.00
120.00
4.38
2.62
0.00
122.00
4.38
2.62
0.00
124.00
4.38
2.62
0.00
126.00
4.38
2.62
0.00
128.00
4.38
2.62
0.00
130.00
4.38
2.62
0.00
132.00
4.38
2.62
0.00
134.00
4.38
2.62
0.00
136.00
4.38
2.62
0.00
138.00
4.38
2.62
0.00
140.00
4.38
2.62
0.00
142.00
4.38
2.62
0.00
144.00
4.38
2.62
0.00
146.00
4.38
2.62
0.00
148.00
4.38
2.62
0.00
150.00
4.38
2.62
0.00
152.00
4.38
2.62
0.00
154.00
4.38
2.62
0.00
156.00
4.38
2.62
0.00
158.00
4.38
2.62
0.00
160.00
4.38
2.62
0.00
162.00
4.38
2.62
0.00
164.00
4.38
2.62
0.00
166.00
4.38
2.62
0.00
168.00
4.38
2.62
0.00
170.00
4.38
2.62
0.00
172.00
4.38
2.62
0.00
174.00
4.38
2.62
0.00
176.00
4.38
2.62
0.00
178.00
4.38
2.62
0.00
180.00
4.38
2.62
0.00
182.00
4.38
2.62
0.00
184.00
4.38
2.62
0.00
186.00
4.38
2.62
0.00
188.00
4.38
2.62
0.00
190.00
4.38
2.62
0.00
192.00
4.38
2.62
0.00
194.00
4.38
2.62
0.00
196.00
4.38
2.62
0.00
198.00
4.38
2.62
0.00
200.00
4.38
2.62
0.00

Pond 1 Charlotte 6-hr 25-yr 25 Year -Charlotte Rainfall=4.38"
Prepared by (enter your company name here) Page 48
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Pond 3P: (Sand Filter 1)
Inflow Area = 1.180 ac, Inflow Depth = 2.62" for 25 Year -Charlotte event
Inflow = 4.22 cfs @ 3.32 hrs, Volume= 0.258 of
Outflow = 2.79 cfs @ 3.52 hrs, Volume= 0.258 af, Atten= 34%, Lag= 11.8 min
Primary = 2.79 cfs @ 3.52 hrs, Volume= 0.258 of
Routing by Stor-Ind method, Time Span= 0.00-200.00 hrs, dt= 0.10 hrs
Peak Elev= 527.89' @ 3.52 hrs Surf.Area= 3,288 sf Storage= 4,087 cf
Plug -Flow detention time= 340.2 min calculated for 0.257 of (100% of inflow)
Center -of -Mass det. time= 345.0 min ( 568.0 - 222.9 )
Volume
Invert Avail.Storage Storage
Description
#1
526.00'
8,858 cf Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation
Surf.Area
Inc.Store
Cum.Store
(feet)
(sq-ft)
(cubic -feet)
(cubic -feet)
526.00
1,233
0
0
527.00
2,125
1,679
1,679
528.00
3,432
2,779
4,458
529.00
5,368
4,400
8,858
Device Routinq Invert Outlet Devices
#1 Primary
523.31'
15.0" x 62.0' long Culvert RCP, square edge headwall, Ke= 0.500
Outlet Invert= 523.00' S= 0.0050 '/' Cc= 0.900 n= 0.012
#2 Device 1
526.00'
Exfiltration
Head (feet) 0.00 1.00 2.00 3.00 4.00
Disch. (cfs) 0.000 0.013 0.018 0.023 0.028
#3 Device 1
527.00'
1.0' 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
#4 Device 1
528.00'
9.0' 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 Primary
528.00'
5.0' long x 10.0' 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) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64
Primary OutFlow Max=2.75 cfs @ 3.52 hrs HW=527.88' (Free Discharge)
1=Culvert (Passes 2.75 cfs of 11.35 cfs potential flow)
2=Exfiltration (Custom Controls 0.02 cfs)
3=Broad-Crested Rectangular Weir (Weir Controls 2.74 cfs @ 3.11 fps)
=Broad -Crested Rectangular Weir ( Controls 0.00 cfs)
= Broad-C rested Rectangular Weir ( Controls 0.00 cfs)

Pond 1
Charlotte 6-hr 25-yr 25 Year -Charlotte Rainfall=4.38"
Prepared by {enter your company name here} Page 49
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Pond 3P: (Sand Filter 1)
Hydrograph
4.22 cfs — Inflow
— Primary
i----------------------------------Inf1��aw Area-=-1-.180,ac--
Peak Elev=527689'
2.79cfsl--------,------,------------------Soae4;0&7-f--
- -, - - - F- -7 - - - - - - - - -,- - - - - - - - - I - - - - - - T - - -,- - - - - -,- - - T - - -,- - - T - - -,- - - T- - -
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200
Time (hours)

Pond 1 Charlotte 6-hr 25-yr 25 Year -Charlotte Rainfall=4.38"
Prepared by (enter your company name here) Page 50
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Hydrograph for Pond 3P: (Sand Filter 1)
Time
Inflow
Storage
Elevation
Primary
(hours)
(cfs)
(cubic -feet)
(feet)
(cfs)
0.00
0.00
0
526.00
0.00
5.00
0.27
2,242
527.25
0.36
10.00
0.00
1,598
526.96
0.01
15.00
0.00
1,385
526.86
0.01
20.00
0.00
1,196
526.76
0.01
25.00
0.00
1,029
526.67
0.01
30.00
0.00
882
526.59
0.01
35.00
0.00
753
526.51
0.01
40.00
0.00
640
526.45
0.01
45.00
0.00
543
526.39
0.01
50.00
0.00
459
526.33
0.00
55.00
0.00
387
526.28
0.00
60.00
0.00
325
526.24
0.00
65.00
0.00
273
526.21
0.00
70.00
0.00
229
526.17
0.00
75.00
0.00
191
526.15
0.00
80.00
0.00
159
526.12
0.00
85.00
0.00
133
526.10
0.00
90.00
0.00
111
526.09
0.00
95.00
0.00
92
526.07
0.00
100.00
0.00
76
526.06
0.00
105.00
0.00
64
526.05
0.00
110.00
0.00
53
526.04
0.00
115.00
0.00
44
526.03
0.00
120.00
0.00
36
526.03
0.00
125.00
0.00
30
526.02
0.00
130.00
0.00
25
526.02
0.00
135.00
0.00
21
526.02
0.00
140.00
0.00
17
526.01
0.00
145.00
0.00
14
526.01
0.00
150.00
0.00
12
526.01
0.00
155.00
0.00
10
526.01
0.00
160.00
0.00
8
526.01
0.00
165.00
0.00
7
526.01
0.00
170.00
0.00
6
526.00
0.00
175.00
0.00
5
526.00
0.00
180.00
0.00
4
526.00
0.00
185.00
0.00
3
526.00
0.00
190.00
0.00
3
526.00
0.00
195.00
0.00
2
526.00
0.00
200.00
0.00
2
526.00
0.00

Pond 1 Charlotte 6-hr 25-yr 25 Year -Charlotte Rainfall=4.38"
Prepared by (enter your company name here) Page 51
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Elevation Primary
(feet)
(cfs)
526.00
0.00
526.02
0.00
526.04
0.00
526.06
0.00
526.08
0.00
526.10
0.00
526.12
0.00
526.14
0.00
526.16
0.00
526.18
0.00
526.20
0.00
526.22
0.00
526.24
0.00
526.26
0.00
526.28
0.00
526.30
0.00
526.32
0.00
526.34
0.00
526.36
0.00
526.38
0.00
526.40
0.01
526.42
0.01
526.44
0.01
526.46
0.01
526.48
0.01
526.50
0.01
526.52
0.01
526.54
0.01
526.56
0.01
526.58
0.01
526.60
0.01
526.62
0.01
526.64
0.01
526.66
0.01
526.68
0.01
526.70
0.01
526.72
0.01
526.74
0.01
526.76
0.01
526.78
0.01
526.80
0.01
526.82
0.01
526.84
0.01
526.86
0.01
526.88
0.01
526.90
0.01
526.92
0.01
526.94
0.01
526.96
0.01
526.98
0.01
527.00
0.01
527.02
0.02
Stage -Discharge for Pond 3P: (Sand Filter 1)
Elevation Primary
(feet)
(cfs)
527.04
0.04
527.06
0.05
527.08
0.08
527.10
0.10
527.12
0.13
527.14
0.16
527.16
0.19
527.18
0.23
527.20
0.26
527.22
0.30
527.24
0.35
527.26
0.39
527.28
0.44
527.30
0.48
527.32
0.53
527.34
0.59
527.36
0.64
527.38
0.70
527.40
0.75
527.42
0.81
527.44
0.88
527.46
0.94
527.48
1.01
527.50
1.08
527.52
1.15
527.54
1.22
527.56
1.29
527.58
1.37
527.60
1.45
527.62
1.53
527.64
1.62
527.66
1.70
527.68
1.79
527.70
1.88
527.72
1.98
527.74
2.08
527.76
2.17
527.78
2.28
527.80
2.38
527.82
2.47
527.84
2.56
527.86
2.65
527.88
2.75
527.90
2.84
527.92
2.94
527.94
3.04
527.96
3.14
527.98
3.24
528.00
3.34
528.02
3.54
528.04
3.84
528.06
4.19
Elevation Primary
(feet)
(cfs)
528.08
4.60
528.10
5.04
528.12
5.52
528.14
6.03
528.16
6.58
528.18
7.15
528.20
7.75
528.22
8.39
528.24
9.06
528.26
9.76
528.28
10.49
528.30
11.24
528.32
12.03
528.34
12.83
528.36
13.66
528.38
14.52
528.40
15.38
528.42
15.67
528.44
15.97
528.46
16.28
528.48
16.60
528.50
16.93
528.52
17.27
528.54
17.61
528.56
17.97
528.58
18.33
528.60
18.70
528.62
19.04
528.64
19.39
528.66
19.74
528.68
20.10
528.70
20.46
528.72
20.83
528.74
21.20
528.76
21.57
528.78
21.95
528.80
22.33
528.82
22.72
528.84
23.11
528.86
23.51
528.88
23.91
528.90
24.31
528.92
24.72
528.94
25.13
528.96
25.54
528.98
25.96
529.00
26.39
529.02
26.82
529.04
27.26
529.06
27.71
529.08
28.16
529.10
28.61
Elevation Primary
(feet)
(cfs)
529.12
29.07
529.14
29.53
529.16
29.99
529.18
30.46
529.20
30.94
529.22
31.39
529.24
31.85
529.26
32.32
529.28
32.78
529.30
33.25
529.32
33.72
529.34
34.20
529.36
34.67
529.38
35.15
529.40
35.64
529.42
36.11
529.44
36.59
529.46
37.07
529.48
37.55
529.50
38.04
529.52
38.53
529.54
39.02
529.56
39.51
529.58
40.00
529.60
40.50
529.62
41.02
529.64
41.56
529.66
42.09
529.68
42.63
529.70
43.17
529.72
43.71
529.74
44.26
529.76
44.81
529.78
45.36
529.80
45.91
529.82
46.47
529.84
47.03
529.86
47.60
529.88
48.16
529.90
48.73
529.92
49.31
529.94
49.88
529.96
50.46
529.98
51.04
530.00
51.62

Pond 1 Charlotte 6-hr 25-yr 25 Year -Charlotte Rainfall=4.38"
Prepared by (enter your company name here) Page 52
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Stage -Area -Storage for Pond 3P: (Sand Filter 1)
Elevation
Surface
Storage
(feet)
(sq-ft)
(cubic -feet)
526.00
1,233
0
526.05
1,278
63
526.10
1,322
128
526.15
1,367
195
526.20
1,411
264
526.25
1,456
336
526.30
1,501
410
526.35
1,545
486
526.40
1,590
565
526.45
1,634
645
526.50
1,679
728
526.55
1,724
813
526.60
1,768
900
526.65
1,813
990
526.70
1,857
1,082
526.75
1,902
1,176
526.80
1,947
1,272
526.85
1,991
1,370
526.90
2,036
1,471
526.95
2,080
1,574
527.00
2,125
1,679
527.05
2,190
1,787
527.10
2,256
1,898
527.15
2,321
2,012
527.20
2,386
2,130
527.25
2,452
2,251
527.30
2,517
2,375
527.35
2,582
2,503
527.40
2,648
2,634
527.45
2,713
2,768
527.50
2,779
2,905
527.55
2,844
3,045
527.60
2,909
3,189
527.65
2,975
3,336
527.70
3,040
3,487
527.75
3,105
3,640
527.80
3,171
3,797
527.85
3,236
3,957
527.90
3,301
4,121
527.95
3,367
4,288
528.00
3,432
4,458
528.05
3,529
4,632
528.10
3,626
4,810
528.15
3,722
4,994
528.20
3,819
5,183
528.25
3,916
5,376
528.30
4,013
5,574
528.35
4,110
5,777
528.40
4,206
5,985
528.45
4,303
6,198
528.50
4,400
6,416
528.55
4,497
6,638
Elevation
Surface
Storage
(feet)
(sq-ft)
(cubic -feet)
528.60
4,594
6,865
528.65
4,690
7,097
528.70
4,787
7,334
528.75
4,884
7,576
528.80
4,981
7,823
528.85
5,078
8,074
528.90
5,174
8,330
528.95
5,271
8,592
529.00
5,368
8,858
529.05
5,368
8,858
529.10
5,368
8,858
529.15
5,368
8,858
529.20
5,368
8,858
529.25
5,368
8,858
529.30
5,368
8,858
529.35
5,368
8,858
529.40
5,368
8,858
529.45
5,368
8,858
529.50
5,368
8,858
529.55
5,368
8,858
529.60
5,368
8,858
529.65
5,368
8,858
529.70
5,368
8,858
529.75
5,368
8,858
529.80
5,368
8,858
529.85
5,368
8,858
529.90
5,368
8,858
529.95
5,368
8,858
530.00
5,368
8,858

Pond 1 Charlotte 6-hr 50 yr 50- Year- Charlotte Rainfall=4.92"
Prepared by (enter your company name here) Page 53
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Time span =0.00-200.00 hrs, dt=0.10 hrs, 2001 points
Runoff by SCS TR-20 method, UH=SCS
Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method
Subcatchment 1S: (Predeveloped) Runoff Area=1.180 ac Runoff Depth=2.38"
Tc=18.4 min CN=75 Runoff=3.76 cfs 0.234 of
Subcatchment 2S: (Post Developed) Runoff Area=1.180 ac Runoff Depth=3.10"
Tc=17.6 min CN=83 Runoff=4.93 cfs 0.305 of
Pond 3P: (Sand Filter 1) Peak Elev=528.01' Storage=4,503 cf Inflow=4.93 cfs 0.305 of
Outflow=3.43 cfs 0.305 of
Total Runoff Area = 2.360 ac Runoff Volume = 0.539 of Average Runoff Depth = 2.74"
100.00% Pervious Area = 2.360 ac 0.00% Impervious Area = 0.000 ac

Pond 1 Charlotte 6-hr 50 yr 50- Year- Charlotte Rainfall=4.92"
Prepared by {enter your company name here} Page 54
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Subcatchment 1 S: (Predeveloped)
Runoff = 3.76 cfs @ 3.30 hrs, Volume= 0.234 af, Depth= 2.38"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-200.00 hrs, dt= 0.10 hrs
Charlotte 6-hr 50-yr 50-Year-Charlotte Rainfall=4.92"
Area (ac) CN Description
1.180 75 See Calculations
1.180 Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
18.4 Direct Entry,
Subcatchment 1 S: (Predeveloped)
Hydrograph
3.76 cfs
Charlotte 6-hr 50,yr 56-Year-Charlotte
Rainfall=4.62"
Runoff Area=1�.180� ac
Runoff Volume=0.234 of
Runoff Depth=2.38"
Tc=18.4 rihin
CN=75
2 -+---+--+---r--+---+------+------+------+------+------+---+--+---+--
1 --i + +---+------ +------------------ - - -
-
--
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200
Time (hours)
— Runoff

Pond 1 Charlotte 6-hr 50 yr 50- Year- Charlotte Rainfall=4.92"
Prepared by (enter your company name here) Page 55
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Hydrograph for Subcatchment 1S: (Predeveloped)
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
0.00
0.00
0.00
0.00
2.00
0.55
0.00
0.00
4.00
4.36
1.94
0.73
6.00
4.92
2.38
0.20
8.00
4.92
2.38
0.00
10.00
4.92
2.38
0.00
12.00
4.92
2.38
0.00
14.00
4.92
2.38
0.00
16.00
4.92
2.38
0.00
18.00
4.92
2.38
0.00
20.00
4.92
2.38
0.00
22.00
4.92
2.38
0.00
24.00
4.92
2.38
0.00
26.00
4.92
2.38
0.00
28.00
4.92
2.38
0.00
30.00
4.92
2.38
0.00
32.00
4.92
2.38
0.00
34.00
4.92
2.38
0.00
36.00
4.92
2.38
0.00
38.00
4.92
2.38
0.00
40.00
4.92
2.38
0.00
42.00
4.92
2.38
0.00
44.00
4.92
2.38
0.00
46.00
4.92
2.38
0.00
48.00
4.92
2.38
0.00
50.00
4.92
2.38
0.00
52.00
4.92
2.38
0.00
54.00
4.92
2.38
0.00
56.00
4.92
2.38
0.00
58.00
4.92
2.38
0.00
60.00
4.92
2.38
0.00
62.00
4.92
2.38
0.00
64.00
4.92
2.38
0.00
66.00
4.92
2.38
0.00
68.00
4.92
2.38
0.00
70.00
4.92
2.38
0.00
72.00
4.92
2.38
0.00
74.00
4.92
2.38
0.00
76.00
4.92
2.38
0.00
78.00
4.92
2.38
0.00
80.00
4.92
2.38
0.00
82.00
4.92
2.38
0.00
84.00
4.92
2.38
0.00
86.00
4.92
2.38
0.00
88.00
4.92
2.38
0.00
90.00
4.92
2.38
0.00
92.00
4.92
2.38
0.00
94.00
4.92
2.38
0.00
96.00
4.92
2.38
0.00
98.00
4.92
2.38
0.00
100.00
4.92
2.38
0.00
102.00
4.92
2.38
0.00
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
104.00
4.92
2.38
0.00
106.00
4.92
2.38
0.00
108.00
4.92
2.38
0.00
110.00
4.92
2.38
0.00
112.00
4.92
2.38
0.00
114.00
4.92
2.38
0.00
116.00
4.92
2.38
0.00
118.00
4.92
2.38
0.00
120.00
4.92
2.38
0.00
122.00
4.92
2.38
0.00
124.00
4.92
2.38
0.00
126.00
4.92
2.38
0.00
128.00
4.92
2.38
0.00
130.00
4.92
2.38
0.00
132.00
4.92
2.38
0.00
134.00
4.92
2.38
0.00
136.00
4.92
2.38
0.00
138.00
4.92
2.38
0.00
140.00
4.92
2.38
0.00
142.00
4.92
2.38
0.00
144.00
4.92
2.38
0.00
146.00
4.92
2.38
0.00
148.00
4.92
2.38
0.00
150.00
4.92
2.38
0.00
152.00
4.92
2.38
0.00
154.00
4.92
2.38
0.00
156.00
4.92
2.38
0.00
158.00
4.92
2.38
0.00
160.00
4.92
2.38
0.00
162.00
4.92
2.38
0.00
164.00
4.92
2.38
0.00
166.00
4.92
2.38
0.00
168.00
4.92
2.38
0.00
170.00
4.92
2.38
0.00
172.00
4.92
2.38
0.00
174.00
4.92
2.38
0.00
176.00
4.92
2.38
0.00
178.00
4.92
2.38
0.00
180.00
4.92
2.38
0.00
182.00
4.92
2.38
0.00
184.00
4.92
2.38
0.00
186.00
4.92
2.38
0.00
188.00
4.92
2.38
0.00
190.00
4.92
2.38
0.00
192.00
4.92
2.38
0.00
194.00
4.92
2.38
0.00
196.00
4.92
2.38
0.00
198.00
4.92
2.38
0.00
200.00
4.92
2.38
0.00

Pond 1 Charlotte 6-hr 50 yr 50- Year- Charlotte Rainfall=4.92"
Prepared by {enter your company name here} Page 56
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Subcatchment 2S: (Post Developed)
Runoff = 4.93 cfs @ 3.28 hrs, Volume= 0.305 af, Depth= 3.10"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-200.00 hrs, dt= 0.10 hrs
Charlotte 6-hr 50-yr 50-Year-Charlotte Rainfall=4.92"
Area (ac) CN Description
1.180 83
1.180 Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
17.6 Direct Entry,
Subcatchment 2S: (Post Developed)
Hydrograph
4.93 cfs
Charlotte 6-hr 50,yr 56-Year-Charlotte
Rainfall=4.62"
a ----r------r------t------t------t-------------t--RunoffArea=1t.180�ac-
Runoff Volume=0.305 of
Runoff Depth=3.10"
Tc=17.6 rihin
s-J---L---1---L---1---L---1---L---1---L---1---1---1---1---1- 1---1---1CN=n
2---'I------'I------'I------'I------'I------'I------'I------'I------'I---
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200
Time (hours)
— Runoff

Pond 1 Charlotte 6-hr 50 yr 50- Year- Charlotte Rainfall=4.92"
Prepared by (enter your company name here) Page 57
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Hydrograph for Subcatchment 2S: (Post Developed)
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
0.00
0.00
0.00
0.00
2.00
0.55
0.01
0.02
4.00
4.36
2.60
0.82
6.00
4.92
3.10
0.22
8.00
4.92
3.10
0.00
10.00
4.92
3.10
0.00
12.00
4.92
3.10
0.00
14.00
4.92
3.10
0.00
16.00
4.92
3.10
0.00
18.00
4.92
3.10
0.00
20.00
4.92
3.10
0.00
22.00
4.92
3.10
0.00
24.00
4.92
3.10
0.00
26.00
4.92
3.10
0.00
28.00
4.92
3.10
0.00
30.00
4.92
3.10
0.00
32.00
4.92
3.10
0.00
34.00
4.92
3.10
0.00
36.00
4.92
3.10
0.00
38.00
4.92
3.10
0.00
40.00
4.92
3.10
0.00
42.00
4.92
3.10
0.00
44.00
4.92
3.10
0.00
46.00
4.92
3.10
0.00
48.00
4.92
3.10
0.00
50.00
4.92
3.10
0.00
52.00
4.92
3.10
0.00
54.00
4.92
3.10
0.00
56.00
4.92
3.10
0.00
58.00
4.92
3.10
0.00
60.00
4.92
3.10
0.00
62.00
4.92
3.10
0.00
64.00
4.92
3.10
0.00
66.00
4.92
3.10
0.00
68.00
4.92
3.10
0.00
70.00
4.92
3.10
0.00
72.00
4.92
3.10
0.00
74.00
4.92
3.10
0.00
76.00
4.92
3.10
0.00
78.00
4.92
3.10
0.00
80.00
4.92
3.10
0.00
82.00
4.92
3.10
0.00
84.00
4.92
3.10
0.00
86.00
4.92
3.10
0.00
88.00
4.92
3.10
0.00
90.00
4.92
3.10
0.00
92.00
4.92
3.10
0.00
94.00
4.92
3.10
0.00
96.00
4.92
3.10
0.00
98.00
4.92
3.10
0.00
100.00
4.92
3.10
0.00
102.00
4.92
3.10
0.00
Time Precip. Excess Runoff
(hours)
(inches)
(inches)
(cfs)
104.00
4.92
3.10
0.00
106.00
4.92
3.10
0.00
108.00
4.92
3.10
0.00
110.00
4.92
3.10
0.00
112.00
4.92
3.10
0.00
114.00
4.92
3.10
0.00
116.00
4.92
3.10
0.00
118.00
4.92
3.10
0.00
120.00
4.92
3.10
0.00
122.00
4.92
3.10
0.00
124.00
4.92
3.10
0.00
126.00
4.92
3.10
0.00
128.00
4.92
3.10
0.00
130.00
4.92
3.10
0.00
132.00
4.92
3.10
0.00
134.00
4.92
3.10
0.00
136.00
4.92
3.10
0.00
138.00
4.92
3.10
0.00
140.00
4.92
3.10
0.00
142.00
4.92
3.10
0.00
144.00
4.92
3.10
0.00
146.00
4.92
3.10
0.00
148.00
4.92
3.10
0.00
150.00
4.92
3.10
0.00
152.00
4.92
3.10
0.00
154.00
4.92
3.10
0.00
156.00
4.92
3.10
0.00
158.00
4.92
3.10
0.00
160.00
4.92
3.10
0.00
162.00
4.92
3.10
0.00
164.00
4.92
3.10
0.00
166.00
4.92
3.10
0.00
168.00
4.92
3.10
0.00
170.00
4.92
3.10
0.00
172.00
4.92
3.10
0.00
174.00
4.92
3.10
0.00
176.00
4.92
3.10
0.00
178.00
4.92
3.10
0.00
180.00
4.92
3.10
0.00
182.00
4.92
3.10
0.00
184.00
4.92
3.10
0.00
186.00
4.92
3.10
0.00
188.00
4.92
3.10
0.00
190.00
4.92
3.10
0.00
192.00
4.92
3.10
0.00
194.00
4.92
3.10
0.00
196.00
4.92
3.10
0.00
198.00
4.92
3.10
0.00
200.00
4.92
3.10
0.00

Pond 1 Charlotte 6-hr 50 yr 50- Year- Charlotte Rainfall=4.92"
Prepared by (enter your company name here) Page 58
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Pond 3P: (Sand Filter 1)
Inflow Area = 1.180 ac, Inflow Depth = 3.10" for 50-Year-Charlotte event
Inflow = 4.93 cfs @ 3.28 hrs, Volume= 0.305 of
Outflow = 3.43 cfs @ 3.45 hrs, Volume= 0.305 af, Atten= 30%, Lag= 10.0 min
Primary = 3.43 cfs @ 3.45 hrs, Volume= 0.305 of
Routing by Stor-Ind method, Time Span= 0.00-200.00 hrs, dt= 0.10 hrs
Peak Elev= 528.01' @ 3.45 hrs Surf.Area= 3,458 sf Storage= 4,503 cf
Plug -Flow detention time= 289.7 min calculated for 0.305 of (100% of inflow)
Center -of -Mass det. time= 294.5 min ( 514.0 - 219.5 )
Volume
Invert Avail.Storage Storage
Description
#1
526.00'
8,858 cf Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation
Surf.Area
Inc.Store
Cum.Store
(feet)
(sq-ft)
(cubic -feet)
(cubic -feet)
526.00
1,233
0
0
527.00
2,125
1,679
1,679
528.00
3,432
2,779
4,458
529.00
5,368
4,400
8,858
Device Routinq Invert Outlet Devices
#1 Primary
523.31'
15.0" x 62.0' long Culvert RCP, square edge headwall, Ke= 0.500
Outlet Invert= 523.00' S= 0.0050 '/' Cc= 0.900 n= 0.012
#2 Device 1
526.00'
Exfiltration
Head (feet) 0.00 1.00 2.00 3.00 4.00
Disch. (cfs) 0.000 0.013 0.018 0.023 0.028
#3 Device 1
527.00'
1.0' 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
#4 Device 1
528.00'
9.0' 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 Primary
528.00'
5.0' long x 10.0' 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) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64
Primary OutFlow Max=3.36 cfs @ 3.45 hrs HW=528.00' (Free Discharge)
1=Culvert (Passes 3.36 cfs of 11.54 cfs potential flow)
2=Exfiltration (Custom Controls 0.02 cfs)
3=Broad-Crested Rectangular Weir (Weir Controls 3.34 cfs @ 3.33 fps)
=Broad -Crested Rectangular Weir (Weir Controls 0.01 cfs @ 0.17 fps)
= Broad-C rested Rectangular Weir (Weir Controls 0.00 cfs @ 0.15 fps)

Pond 1
Charlotte 6-hr 50 yr 50- Year- Charlotte Rainfall=4.92"
Prepared by {enter your company name here} Page 59
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Pond 3P: (Sand Filter 1)
Hydrograph
4.93 cfs — Inflow
----- -- ---F -- ------ - -- -- i --- -- ---- ----T - - - ---T - - - --- --- —Primary
Inflow Area=1.180 a+c
i - ---! -----'r------' ---- --- Y--Peal����-€hev=5286--l'--
3.43cfs Storage=4,503 cf
-r---r--r---r--r---r--r---r--r---r--r---r--r---i---r---i---t---i---r
10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200
Time (hours)

Pond 1 Charlotte 6-hr 50 yr 50- Year- Charlotte Rainfall=4.92"
Prepared by (enter your company name here) Page 60
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Hydrograph for Pond 3P: (Sand Filter 1)
Time
Inflow
Storage
Elevation
Primary
(hours)
(cfs)
(cubic -feet)
(feet)
(cfs)
0.00
0.00
0
526.00
0.00
5.00
0.31
2,287
527.26
0.40
10.00
0.00
1,599
526.96
0.01
15.00
0.00
1,386
526.86
0.01
20.00
0.00
1,197
526.76
0.01
25.00
0.00
1,029
526.67
0.01
30.00
0.00
882
526.59
0.01
35.00
0.00
753
526.51
0.01
40.00
0.00
641
526.45
0.01
45.00
0.00
543
526.39
0.01
50.00
0.00
459
526.33
0.00
55.00
0.00
387
526.28
0.00
60.00
0.00
326
526.24
0.00
65.00
0.00
273
526.21
0.00
70.00
0.00
229
526.17
0.00
75.00
0.00
191
526.15
0.00
80.00
0.00
160
526.12
0.00
85.00
0.00
133
526.10
0.00
90.00
0.00
111
526.09
0.00
95.00
0.00
92
526.07
0.00
100.00
0.00
77
526.06
0.00
105.00
0.00
64
526.05
0.00
110.00
0.00
53
526.04
0.00
115.00
0.00
44
526.03
0.00
120.00
0.00
36
526.03
0.00
125.00
0.00
30
526.02
0.00
130.00
0.00
25
526.02
0.00
135.00
0.00
21
526.02
0.00
140.00
0.00
17
526.01
0.00
145.00
0.00
14
526.01
0.00
150.00
0.00
12
526.01
0.00
155.00
0.00
10
526.01
0.00
160.00
0.00
8
526.01
0.00
165.00
0.00
7
526.01
0.00
170.00
0.00
6
526.00
0.00
175.00
0.00
5
526.00
0.00
180.00
0.00
4
526.00
0.00
185.00
0.00
3
526.00
0.00
190.00
0.00
3
526.00
0.00
195.00
0.00
2
526.00
0.00
200.00
0.00
2
526.00
0.00

Pond 1 Charlotte 6-hr 50 yr 50- Year- Charlotte Rainfall=4.92"
Prepared by (enter your company name here) Page 61
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Elevation Primary
(feet)
(cfs)
526.00
0.00
526.02
0.00
526.04
0.00
526.06
0.00
526.08
0.00
526.10
0.00
526.12
0.00
526.14
0.00
526.16
0.00
526.18
0.00
526.20
0.00
526.22
0.00
526.24
0.00
526.26
0.00
526.28
0.00
526.30
0.00
526.32
0.00
526.34
0.00
526.36
0.00
526.38
0.00
526.40
0.01
526.42
0.01
526.44
0.01
526.46
0.01
526.48
0.01
526.50
0.01
526.52
0.01
526.54
0.01
526.56
0.01
526.58
0.01
526.60
0.01
526.62
0.01
526.64
0.01
526.66
0.01
526.68
0.01
526.70
0.01
526.72
0.01
526.74
0.01
526.76
0.01
526.78
0.01
526.80
0.01
526.82
0.01
526.84
0.01
526.86
0.01
526.88
0.01
526.90
0.01
526.92
0.01
526.94
0.01
526.96
0.01
526.98
0.01
527.00
0.01
527.02
0.02
Stage -Discharge for Pond 3P: (Sand Filter 1)
Elevation Primary
(feet)
(cfs)
527.04
0.04
527.06
0.05
527.08
0.08
527.10
0.10
527.12
0.13
527.14
0.16
527.16
0.19
527.18
0.23
527.20
0.26
527.22
0.30
527.24
0.35
527.26
0.39
527.28
0.44
527.30
0.48
527.32
0.53
527.34
0.59
527.36
0.64
527.38
0.70
527.40
0.75
527.42
0.81
527.44
0.88
527.46
0.94
527.48
1.01
527.50
1.08
527.52
1.15
527.54
1.22
527.56
1.29
527.58
1.37
527.60
1.45
527.62
1.53
527.64
1.62
527.66
1.70
527.68
1.79
527.70
1.88
527.72
1.98
527.74
2.08
527.76
2.17
527.78
2.28
527.80
2.38
527.82
2.47
527.84
2.56
527.86
2.65
527.88
2.75
527.90
2.84
527.92
2.94
527.94
3.04
527.96
3.14
527.98
3.24
528.00
3.34
528.02
3.54
528.04
3.84
528.06
4.19
Elevation Primary
(feet)
(cfs)
528.08
4.60
528.10
5.04
528.12
5.52
528.14
6.03
528.16
6.58
528.18
7.15
528.20
7.75
528.22
8.39
528.24
9.06
528.26
9.76
528.28
10.49
528.30
11.24
528.32
12.03
528.34
12.83
528.36
13.66
528.38
14.52
528.40
15.38
528.42
15.67
528.44
15.97
528.46
16.28
528.48
16.60
528.50
16.93
528.52
17.27
528.54
17.61
528.56
17.97
528.58
18.33
528.60
18.70
528.62
19.04
528.64
19.39
528.66
19.74
528.68
20.10
528.70
20.46
528.72
20.83
528.74
21.20
528.76
21.57
528.78
21.95
528.80
22.33
528.82
22.72
528.84
23.11
528.86
23.51
528.88
23.91
528.90
24.31
528.92
24.72
528.94
25.13
528.96
25.54
528.98
25.96
529.00
26.39
529.02
26.82
529.04
27.26
529.06
27.71
529.08
28.16
529.10
28.61
Elevation Primary
(feet)
(cfs)
529.12
29.07
529.14
29.53
529.16
29.99
529.18
30.46
529.20
30.94
529.22
31.39
529.24
31.85
529.26
32.32
529.28
32.78
529.30
33.25
529.32
33.72
529.34
34.20
529.36
34.67
529.38
35.15
529.40
35.64
529.42
36.11
529.44
36.59
529.46
37.07
529.48
37.55
529.50
38.04
529.52
38.53
529.54
39.02
529.56
39.51
529.58
40.00
529.60
40.50
529.62
41.02
529.64
41.56
529.66
42.09
529.68
42.63
529.70
43.17
529.72
43.71
529.74
44.26
529.76
44.81
529.78
45.36
529.80
45.91
529.82
46.47
529.84
47.03
529.86
47.60
529.88
48.16
529.90
48.73
529.92
49.31
529.94
49.88
529.96
50.46
529.98
51.04
530.00
51.62

Pond 1 Charlotte 6-hr 50 yr 50- Year- Charlotte Rainfall=4.92"
Prepared by (enter your company name here) Page 62
HydroCAD® 8.00 s/n 004317 © 2006 HydroCAD Software Solutions LLC 6/6/2019
Stage -Area -Storage for Pond 3P: (Sand Filter 1)
Elevation
Surface
Storage
(feet)
(sq-ft)
(cubic -feet)
526.00
1,233
0
526.05
1,278
63
526.10
1,322
128
526.15
1,367
195
526.20
1,411
264
526.25
1,456
336
526.30
1,501
410
526.35
1,545
486
526.40
1,590
565
526.45
1,634
645
526.50
1,679
728
526.55
1,724
813
526.60
1,768
900
526.65
1,813
990
526.70
1,857
1,082
526.75
1,902
1,176
526.80
1,947
1,272
526.85
1,991
1,370
526.90
2,036
1,471
526.95
2,080
1,574
527.00
2,125
1,679
527.05
2,190
1,787
527.10
2,256
1,898
527.15
2,321
2,012
527.20
2,386
2,130
527.25
2,452
2,251
527.30
2,517
2,375
527.35
2,582
2,503
527.40
2,648
2,634
527.45
2,713
2,768
527.50
2,779
2,905
527.55
2,844
3,045
527.60
2,909
3,189
527.65
2,975
3,336
527.70
3,040
3,487
527.75
3,105
3,640
527.80
3,171
3,797
527.85
3,236
3,957
527.90
3,301
4,121
527.95
3,367
4,288
528.00
3,432
4,458
528.05
3,529
4,632
528.10
3,626
4,810
528.15
3,722
4,994
528.20
3,819
5,183
528.25
3,916
5,376
528.30
4,013
5,574
528.35
4,110
5,777
528.40
4,206
5,985
528.45
4,303
6,198
528.50
4,400
6,416
528.55
4,497
6,638
Elevation
Surface
Storage
(feet)
(sq-ft)
(cubic -feet)
528.60
4,594
6,865
528.65
4,690
7,097
528.70
4,787
7,334
528.75
4,884
7,576
528.80
4,981
7,823
528.85
5,078
8,074
528.90
5,174
8,330
528.95
5,271
8,592
529.00
5,368
8,858
529.05
5,368
8,858
529.10
5,368
8,858
529.15
5,368
8,858
529.20
5,368
8,858
529.25
5,368
8,858
529.30
5,368
8,858
529.35
5,368
8,858
529.40
5,368
8,858
529.45
5,368
8,858
529.50
5,368
8,858
529.55
5,368
8,858
529.60
5,368
8,858
529.65
5,368
8,858
529.70
5,368
8,858
529.75
5,368
8,858
529.80
5,368
8,858
529.85
5,368
8,858
529.90
5,368
8,858
529.95
5,368
8,858
530.00
5,368
8,858