SW3190505_Calcs_20190924

YARBROUGH -WILLIAMS& HOULE, INC.
Planning • Surveying • Engineering
NCBELS C-0475
SC COA332
STORMWATER MANAGEMENT
CALCULATIONS
FOR
The Courtyards on Lawyers Road
May 24, 2019
REV. August 27,2019
CONTENTS:
• STORM DRAINAGE CALCULATIONS
• SPREAD CALCULATIONS
• DROP INLET DEPTH CALCULATIONS
• EROSION CONTROL SKIMMER BASIN CALCULATIONS
• EROSION CONTROL SEDIMENT BASIN CALCULATIONS
• EROSION CONTROL TEMPORARY DITCH CALCULATIONS
• DETENTION SUMMARY
• WET POND # 1- CALCULATIONS, HYDROCAD REPORT
• WET POND #2- CALCULATIONS, HYDROCAD REPORT
730 Windsor Oak Court, Charlotte, NC 28273 9 P.O. Box 1198, Pineville, NC 28134 • 704.556.1990 a fax [phone]

STORM DRAINAGE
CALCULATIONS

--- ---
YARBROUGH-WILLIAMS & HOULE, INC.REV.
Planning • Surveying • Engineering
PROJECT NAME:
-
THE COURTYARDS OLA RS ROAD
REV.
8/27/2019
STORM DRAINAGE CALCULATIONS
P.
REV.VERSION
7.26.13
cHnRL
DATE:
JANUARY15,2019
Phon
REV.
Fax:
OUTPUT FOR SUBMITTAL
FROM
STRUCTURE
STRUCTURE
TYPE
TO
STRUCTURE
PIPE
COVER
AT STRUCT.
LENGTH
FEET
SLOPE
%
SURFACE
DRAINAGE
AREA
LATERAL
PIPES
AREA
DRAINAGE
AREA
TOTAL
DESIGN
FREQUENCY
10/25/50/100
MANNING'S
n
RUNOFF
COEFF.
C
SECTION
FLOW TIME
MINUTES
ACCUM.
FLOW TIME
MINUTES
Tc
USED
MINUTES
RAINFALL
INTENSITY
10,25,50,100
RUNOFF
Q(CFS)
FES / HW
Q MAX
HW/D: 1.2
PIPE
DIAMETER
REQUIRED
PIPE
DIAMETER
DESIGNED
AREA
OF
FLOW (SF)
WETTED
PERIMETER
FT
DESIGN
VELOCITY
FPS
1
2
4
5
6
7
8
9
10
HW
MH
DI
DI
MH
MH
MH
MH
MH
2
3
4
5
6
7
8
9
10
11
2.0
1.0
1.0
2.2
2.0
1.2
2.7
5.7
8.00
124.88
82.59
36.80
102.84
74.41
120.72
191.14
54.40
9.25
2.24
5
0.97
0.50
0.50
0.50
0.50
0.50
0.50
17.33
4
0.63
1.10
3.33
4.85
17.33
20.66
21.72
22.82
22.82
22.82
22.82
22.82
27.67
25
25
25
25
25
25
25
25
25
0.012
0.012
0.012
0.012
0.012
0.012
0.012
0.012
0.012
0.40
0.40
0.40
0.40
0.40
0.40
0.40
0.40
0.40
0.01
0.16
7
0.14
0.08
0.23
0.16
0.27
0.42
0.12
43.00
43.01
4 7
43.44
43.58
43.66
43.89
44.05
44.32
44.74
43.00
43.01
4
43.44
43.58
43.66
43.89
44.05
44.32
44.74
3.53
3.53
.5
3.53
3.53
3.53
3.53
3.43
3.43
3.43
24.46
29.16
.7
30.65
32.20
32.20
32.20
31.33
31.33
37.99
49.32
15.79
22.00
26.23
30.25
30.25
30.25
29.94
29.94
32.18
36
36
36
36
36
36
36
36
36
1.23
2.29
3.17
4.25
4.25
4.25
4.16
4.16
4.86
2.17
3.39
5.
4.33
5.46
5.46
5.46
5.37
5.37
6.12
19.91
12.73
7.
9.65
7.58
7.58
7.58
7.53
7.53
7.81
137
13
12
DI
DI
HW
13
2
10
2.0
4.2
81.57
142.45
16.70
0.50
0.97
0.50
2.09
1.24
4.85
2.09
3.33
4.85
500.60
50EO.
500.60
0.60
0.23
0.29
0.04
5.00
5.23
5.00
5.00
5.23
5.00
9.00
8.85
9.00
11.29
17.68
26.19
31.27
20.42
21.34
27.99
24
24
30
1.93
2.12
3.67
3.71
4.02
5.50
5.85
8.33
7.14
15
16
17
18
19
20
21
22
23
DI
DI
DI
DI
DI
DI
MH
MH
MH
16
17
18
19
20
21
22
23
25B
1.0
1.0
1.0
1.0
1.0
0.6
3.5
2.1
3.4
161.67
163.27
163.20
162.00
169.52
192.49
113.58
87.29
141.26
1.52
1.57
1.84
1.57
1.33
0.50
0.50
0.50
0.50
0.29
1.65
5.78
1.15
0.70
0.69
0.29
1.94
7.72
8.87
9.57
10.26
10.26
10.26
10.26
25
25
25
25
25
25
25
25
25
0.012
0.012
0.012
0.012
0.012
0.012
0.012
0.012
0.012
0.40
0.40
0.40
0.40
0.40
0.40
0.40
0.40
0.40
0.74
0.42
0.28
0.29
0.32
0.51
0.30
0.23
0.37
34.70
35.44
35.87
36.15
36.44
36.75
37.26
37.56
37.78
34.70
35.44
35.87
36.15
36.44
36.75
37.26
37.56 1
37.78
3.96
3.91
3.91
3.86
3.86
3.86
3.82
3.82
3.82
0.46
3.04
12.08
13.71
14.79
15.86
15.66
15.66
15.66
4.99
10.07
16.41
17.72
18.82
23.19
23.08
23.08
23.08
15
15
24
24
30
30
30
30
30
0.13
0.47
1.25
1.45
1.65
2.52
2.45
2.45
2.45
0.63
1.61
2.64
2.95
2.90
4.00
3.93
3.93
3.93
3.62
6.41
9.65
9.45
8.96
6.30
6.38
6.38
6.38
26
27
DI
MH
27
28
2.0
1.0
200.45
64.00
0.75
0.60
0.64
0.64
0.64
50
50
0.012
0.012
0.60
0.60
0.67
0.23
5.00
5.67
5.00
5.67
9.00
8.70
3.46
3.34
12.14
12.50
15
15
0.69
0.72
2.16
2.24
5.00
4.62
29
30
31
32
33
34
35
36
37
38
39
CB
CB
CB
CB
CB
CB
CB
CB
CB
CB
DI
30
31
32
33
34
35
36
37
38
39
40
2.0
2.1
2.3
2.5
4.2
3.9
2.7
2.4
2.0
2.0
2.7
24.00
41.34
24.00
51.65
106.49
290.68
108.00
162.00
132.07
100.02
73.51
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.75
0.97
0.50
0.50
0.39
0.50
0.39
0.34
0.08
0.14
0.38
0.12
0.19
0.18
0.16
0.77
0.35
0.34
0.83
0.32
0.49
0.46 1
1.98 1
0.39
0.89
1.28
2.39
2.82
3.30
4.51
4.95
5.63
6.27
8.41
10
10
10
10
10
10
10
10
10
10
10
0.012
0.012
0.012
0.012
0.012
0.012
0.012
0.012
0.012
0.012
0.012
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.10
0.15
0.08
0.14
0.28
0.75
0.26
0.36
0.25
0.24
0.16
5.00
5.10
5.25
5.33
5.47
5.75
6.51
6.77
7.12
7.37
7.61
5.00
6.10
5.25
5.33
5.47
5.75
6.51
6.77
7.12
7.37 1
7.61 1
7.03
6.91
6.91
6.91
6. 9 11
6.79
6.55
6.55
6.44
6.44
6.32
1.65
3.69
5.31
9.91
11.69
13.45
17.74
19.47
21.74
24.21
31.87
9.58
12.97
14.87
18.79
19.99
21.07
23.37
23.24
23.07
27.18
30.13
15
15
15
24
24
24
24
24
30
30
36
0.43
0.78
1.06
1.65
1.85
2.08
2.60
2.56
2.45
3.44
4.251
1.49
2.39
3.18
3.27
3.58
3.96
4.84
4.77
3.93
5.18
5.46
3.84
4.71
4.98
6.00
6.32
6.45
6.83
7.60
8.86
7.04
7.50

YARBROUGH-WILLIAMS & HOULE INC.
Planning • Surveying • Engineering
PROJECT NAME:
STORM DRAINAGE CALCULATIONS
VERSION 7.26.13
THE COURTYARDS ON LAWYERS ROAD
P. O .BOX 7007
cHARLorrE, N.C. 28241
REV.
8/27/2019
REV.
REV.
DATE:
JANUARY15,2019
Phone: [phone]
REV.
Fax: [phone]
OUTPUT FOR SUBMITTAL
PIPE
SURFACE
LATERAL
DRAINAGE
DESIGN
RUNOFF
COEFF.
C
SECTION
FLOW TIME
MINUTES
ACCUM.
FLOW TIME
MINUTES
Tc
USED
MINUTES
RAINFALL
INTENSITY
10,25,50,100
RUNOFF
Q(CFS)
FES / HW
Q MAX
HW/D- 1.2
PIPE
DIAMETER
REQUIRED
PIPE
DIAMETER
DESIGNED
AREA
OF
FLOW (SF)
FROM
STRUCTURE
STRUCTURE
TYPE
TO
STRUCTURE
COVER
AT STRUCT.
LENGTH
FEET
SLOPE
%
DRAINAGE
AREA
PIPES
AREA
AREA
TOTAL
FREQUENCY
10/25/50/100
MANNING'S
Il
WETTED
PERIMETER
FT
DESIGN
VELOCITY
FPS
7.77
7.87
7.92
5.00
5.86
6.54
6.97
5.00
5.10
5.81
6.39
6.73
6.80
5.00
5.11
5.00
5.00
5.00
7.77
7.87
7.92
5.00
5.86
6.54
6.97
5.00
5.10
5.81
6.39
6.73
6.80
5.00
5.11
5.00
5.00
5.00
6.32 46.08 34.60
6.32 47.79 35.07
6.32 51.39 36.04
7.03 0.97 7.36
6.79 3.10 11.15
6.55 5.78 13.74
6.55 7.79 14.44
7.03 1.65 9.58
6.91 2.90 11.04
6.79 6.81 15.23
6.67 10.53 18.04
6.55 13.09 20.86
6.55 14.31 21.57
7.03 1.39 9.00
6.91 1.82 9.96
7.03 2.07 10.44
7.03 2.02 10.36
7.03 1.94 10.19
40
41
42
DI
CB
DCB
41
42
43
2.9
2.4
8.5
47.73
24.00
50.00
0.50
0.50
0.50
1 0.11
0.45
0.65
3.64
0.30
12.16
12.61
13.56
10
10
10
0.012
0.012
0.012
0.60
0.60
0.60
0.10
0.05
0.10
8.10
36
36
5.69
5.84
7.07
7.25
8.18
42
6.03
6.59
8.53
44
45
46
47
DI
DI
DI
DI
45
46
47
39
2.0
2.0
2.0
2.0
216.66 66
216.
166.27
112.58
0.85
0.95
1.08
1.51
0.23
0.53
0.71
0.51
0.
0.76 76
1.47
1.98
10
10
10
10
0.012
0.012
0.012
0.012
0.60
0.60
0.60
0.60
0.86
0.68
0.43
0.24
15
0.27
1.06
3.63
15
0.58
1.88
5.32
15
0.89
2.67
6.51
15
0.99
2.94
7.89
48
49
50
51
52
53
DCB
CB
DCB
CB
CB
CB
49
50
51
52
53
40
2.
2.1
2.0
2.0
2.0
2.3
24.00
216.6.00
216.00
143.42
24.00
81.00
0.
0.88 88
0.87
0.84
0.60
0.60
0.3
0.31
0.48
0.48
0.26
0.31
0.49
0.48
0.44
0.
0.70 70
1.67
2.63
3.33
3.64
10
10
10
10
10
10
0.012
0.012
0.012
0.012
0.012
0.012
0.60
0.60
0.60
0.60
0.60
0.60
0.10
0.70
0.58
0.35
0.06
0.20
15
0.43
1.49
3.84
15
0.57
1.84
5.12
24
1.10
2.39
6.21
24
1.53
3.08
6.88
24
2.05
3.89
6.40
24
2.16
4.08
6.62
54
55
CB
CB
55
52
2.0
2.1
24.00
59.18
0.60
0.60
0.33
0.11
0.33
0.44
10
10
0.012
0.012
0.60
0.60
0.11
0.25
15
0.38
1.37
3.64
15
0.46
1.57
3.98
56
DCB
50
2.0
24.00
0.60
0.49
0.49
10
0.012
0.60
0.10
15
0.50
1.69
4.10
57
CB
51
2.0
24.00
0.60
0.48
0.48
10
0.012
0.60
0.10
15
0.50
1.69
4.01
58
DCB
38
2.0
24.00
0.60
0.46
0.46
10
0.012
0.60
0.10
15
0.49
1.65
3.97
59
DCB
37
2.0
24.00
0.60
0.49
0.49
10
0.012
0.60
0.10
5.00
5.00
7.03
2.07
10.44
15
0.50
1.69
4.10
1.35
60
DCB
36
2.0
24.00
0.60
0.32
0.32
10
0.012
0.60
0.11
5.00
5.00
7.03
8.90
15
0.38
1.37
3.53
2.02
3.44
61
62
CB
CB
62
35
2.0
2.0
128.68
24.00
1.07
0.60
0.48
0.35
0.48
0.83
10
10
0.012
0.012
0.60
0.60
0.44
0.09
5.00
5.44
5.00
5.44
7.03
6.91
9.29
15
0.41
1.45
4.90
12.64
15
0.74
2.28
4.66
63
DCB
34
2.0
24.00
0.60
0.34
0.34
10
0.012
0.60RO.96
5.00
7.03
1.43
9.10
15
0.40
1.41
3.61
64
CB
33
2.0
24.00
0.60
0.35
0.35
10
0.012
0.605.00
R5.
7.03
1.48
9.20
15
0.40
1.41
3.71
65
66
CB
CB
66
32
2.0
2.2
24.40
259.24
0.60
0.60
0.40
0.37
0.40
0.77
10
10
0.012
0.012
0.605.00
0.605.11
7.03
6.91
1.69
3.19
9.67
12.29
15
15
0.44
0.71
1.53
3.81
2.20
4.52

PROJECT NAME
l
THE COURTYARDS ON LAWYERS ROAD
_ YARBROUGH-WILLIAMS & HOULE, INC.
Planning •Surveying • Engineering
REV.
8/27/2019
STORM DRAINAGE CALCULATIONS
P. O .BOX 7007
REV.
VERSION 7.26.13
Z
CHARLOTTE, N.C. zszal
REV.
DATE:
JANUARY15,2019
Phone: [phone]
REV.
Fax: [phone]
OUTPUT FOR SUBMITTAL
FROM
STRUCTURE
STRUCTURE
TYPE
TO
STRUCTURE
PIPE
COVER
AT STRUCT.
LENGTH
FEET
SLOPE
%
SURFACE
DRAINAGE
AREA
LATERAL
PIPES
AREA
DRAINAGE
AREA
TOTAL
DESIGN
FREQUENCY
10/25/50/100
MANNING'S
n
RUNOFF
COEFF.
C
SECTION
FLOW TIME
MINUTES
ACCUM.
FLOW TIME
MINUTES
Tc
USED
MINUTES
RAINFALL
INTENSITY
RUNOFF
FES / HW
Q MAX
PIPE
DIAMETER
PIPE
DIAMETE R
AREA
OF
WETTED
DESIGN
PERIMETER
VELOCITY
10,25,50,100
Q(CFS)
HW/D: 1.2
REQUIRED
DESIGNED
FLOW (SF)
FT
FPS
67
68
69
70
71
72
73
74
75
76
91
92A
92
78
79
80
80A
81
82
83
84
85
CB
CB
CB
CB
CB
CB
CB
CB
DCB
DCB
DCB
CB
CB
CB
CB
CB
CB
DI
MH
CB
CB
MH
68
69
70
71
72
73
74
75
76
91
92A
92
78
79
80
81
81
82
83
84
85
86
2.0
2.1
2.0
2.0
2.3
2.0
2.3
3.1
3.5
3.9
4.9
6.5
6.4
6.6
6.6
6.3
6.4
7.7
9.5
9.8
8.2
5.6
24.00
105.08
108.00
24.00
130.76
24.00
40.04
24.00
101.77
201.50
215.50
98.08
24.52
51.11
134.24
34.83
34.83
141.10
235.74
152.26
200.00
25.70
0.60
0.67
0.81
0.60
0.69
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.50
0.50
0.50
0.50
0.50
0.50
0.50
0.50
0.33
0.32
0.28
0.28
0.35
0.23
0.46
0.10
0.82
0.35
0.35
0.34
0.32
0.50
0.09
0.19
0.24
0.04
0.10
0.11
0.84
1.17
0.67
0.99
4.33
5.72
0.16
0.11
0.80
2.39
0.33
0.65
0.93
1.21
2.40
2.63
3.09
4.36
4.69
6.18
6.53
6.87
7.19
7.69
8.77
13.29
13.53
19.29
19.45
19.66
20.57
22.96
10 0.012 0.60
10 0.012 0.60
10 0.012 0.60
10 0.012 0.60
10 0.012 0.60
10 0.012 0.60
10 0.012 0.60
10 0.012 0.60
10 0.012 0.60
10 0.012 0.60
10 0.012 0.60
10 0.012 0.60
10 0.012 0.60
10 0.012 0.60
10 0. 112 0.60
10 0.012 0.60
10 0.012 0.60
10 0.012 0.60
10 0.012 0.60
10 0.012 0.60
10 0.012 0.60
10 0.012 0.60
0.11
0.39
0.34
0.08
0.34
0.07
0.10
0.06
0.36
0.23
0.48
0.22
0.05
0.11
0.29
0.05
0.07
0.26
0.43
0.28
0.37
0.05
5.00
5.11
5.50
5.84
5.92
6.26
6.32
6.43
6.48
6.85
7.08
7.55
7.77
7.83
7.93
8.23
8.27
8.34
8.60
9.04
9.32
9.69
5.00
5.11
5.50
5.84
5.92
6.26
6.32
6.43
6.48
6.85
7.08
7.55
7.77
7.83
7.93
8.23
8.27
8.34
8.60
9.04
9.32
9.69
1.37
1.92
3.64
4.51
7.03
6.91
1.39
2.70
9.00
11.29
15
15
0.38
0.60
6.91
6.79
6.79
6.67
6.67
6.67
6.67
6.55
3.86
4.93
9.78
10.53
12.37
17.46
18.78
24.30
12.45
14.46
18.24
19.22
20.42
23.24
23.88
26.30
15
15
24
24
24
30
36
36
0.72
0.99
1.53
1.73
1.93
2.52
2.64
3.26
2.24
2.94
3.08
3.39
3.71
4.00
3.77
4.43
5.34
4.99
6.39
6.39
08
6.41
6.94
7.11
7.44
6.44
6.32
6.32
6.32
6.32
6.20
6.20
6.20
6.08
5.96
5.96
5.84
25.21
26.03
27.25
29.14
33.23
49.41
50.31
71.72
70.93
70.29
73.55
80.45
26.67
26.99
27.46
28.16
30.61
35.52
35.76
40.84
40.67
40.54
41.23
42.64
42
42
42
42
42
42
42
42
42
42
42
48
3.35
3.47
3.59
3.71
4.32
5.91
5.91
7.95
7.85
7.85
8.15
8.49
4.18
4.29
4.40
4.51
5.06
6.48
6.48
8.46
8.35
8.35
8.68
8.04
7.52
7.49
7.58
7.85
7.69
8.37
8.52
9.02
9.04
8.96
9.02
9.47
87
88
88A
89
DI
DI
DI
DI
88
88A
89
74
2.0
2.0
2.0
2.0
165.13
165.13
133.49
137.44
0.86
0.85
0.90
0.60
0.15
0.40
0.30
0.32
0.15
0.55
0.85
1.17
10
10
10
10
0.012
0.012
0.012
0.012
0.60
0.60
0.60
0.60
1.22
0.59
0.42
0.47
5.00
6.22
6.81
7.23
5.00
6.22
6.81
7.23
7.03
6.67
6.55
6.44
0.63
2.20
3.34
4.52
6.25
10.02
11.59
14.00
15
15
15
15
0.20
0.47
0.63
0.92
0.86
1.61
2.00
2.75
3.16
4.65
5.31
4.92
90
HW
71
34.36
4.34
0.84
0.84
10
0.012
0.60
0.06
5.00
5.00
7.03
3.54
5.53
8.82
15
0.37
1.33
9.63
77
DCB
76
2.0
24.00
0.62
0.67
0.67
10
0.012
0.60
0.09
5.00
5.00
7.03
2.83
11.65
15
0.63
2.00
4.49
93
DI
79
2.0
34.13
1.55
0.99
0.99
10
0.012
0.60
0.08
5.00
5.00
7.03
4.18
11.37
15
0.60
1.92
6.98
94
CB
83
2.0
24.00
0.79
0.11
0.11
10
0.012
0.60
0.14
5.00
5.00
7.03
0.46
q5.66
15
01695
96
DI
CB
96
84
3.0
2.0
24.00
24.00
4.60
0.60
0.44
0.44
0.80
0.80
10
10
0.012
0.012
0.60
0.60
010
0.09
500
5.10
5.00
5.10
703
6.91
1.52.
3.32
12.47
15
15
0.21
0.90
7.12
0.72
2.24
4.59
0.60
0.09
5.00
5.00
7.03
8.06
13.93
15
0.92
2.75
97
DI
98
2.0
47.51
1.96
1.91
1.91
10
0.012
8.78

PROJECT NAME:
STORM DRAINAGE CALCULATIONS
VERSION 7.26.13
THE COURTYARDS ON LAWYERS ROAD
P. O .BOX 7007
YARBROUGH-WILLIAMS & HOULE, INC.
Planning • Surveying • Engineering
REV.8/27/2019
CHARLOTTE, N.C. 28241
Phone: [phone]
Fax: [phone]
DATE:
JANUARY15,2019
OUTPUT FOR SUBMITTAL
FROM
STRUCTURE
STRUCTURE
TYPE
TO
STRUCTURE
PIPE
COVER
AT STRUCT.
LENGTH
FEET
SLOPE
%
SURFACE
DRAINAGE
AREA
LATERAL
PIPES
AREA
DRAINAGE
AREA
TOTAL
DESIGN
FREQUENCY
10/25/50/100
MANNING'S
n
RUNOFF
COEFF.
C
SECTION
FLOW TIME
MINUTES
ACCUM.
FLOW TIME
MINUTES
11 Tc
USED
RAINFALL
FES / HW
PIPE
PIPE
AREA
WETTED
DESIGN
INTENSITY
RUNOFF
Q MAX
DIAMETER
DIAMETER
OF
PERIMETER
VELOCITY
MINUTES
10,25,50,100
Q(CFS)
HW/D: 1.2
REQUIRED
DESIGNED
FLOW (SF)
FT
FPS
98
99
CB
CB
99
85
2.0
2.3
24.00
55.79
0.60
1.80
0.34
0.14
2.25
2.39
10
10
0.012
0.012
0.60
0.60
0.07
0.10
5.09
5.16
5.09
6.91
9.33
18.37
24
1.57
3.14
5.94
5.16
6.91
9.91
15.29
24
1.10
2.39
9.05
100
101
102
103
104
105
106
107
CB
CB
CB
DCB
CB
CB
CB
DCB
101
102
103
104
105
106
107
80
2.0
2.0
2.0
2.0
2.0
2.0
5.1
5.4
72.66
105.00
166.39
149.48
100.47
171.19
24.00
39.60
1.18
0.85
0.99
0.99
0.90
0.50
0.50
0.50
0.32
0.20
0.32
0.49
0.47
0.29
0.30
0.53
633
0.33
0.35
0.40
0.32
0.85
1.50
2.34
3.21
3.50
3.80
4.33
10
10
10
10
10
10
10
10
0.012
0.012
0.012
0.012
0.012
0.012
0.012
0.012
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.27
0.33
0.44
0.35
0.23
0.47
0.07
0.11
5.00
5.27
5.59
6.03
6.38
6.61
7.08
7.14
5.00
5.27
5.59
6.03
6.38
7.03
1.35
7.83
15
0.30
1.14
4.57
6.91
3.52
11.94
15
0.66
2.08
5.34
5.34
6.79
6.67
6.67
6.11
9.37
12.85
14.27
16.74
19.19
15
18
24
0.66
1.32
1.73
2.08
3.30
3.39
7.09
7.43
6.61
7.08
7.14
6.55
13.76
21.99
24
2.27
4.27
6.05
6.44
6.44
14.67
16.72
22.53
23.66
24
24
2.39
2.66
4.46
4.96
6.15
6.28
109
CB
101
2.0
24.00
0.60
0.33
0.33
10
0.012
0.60
0.11
5.00
5.00
7.03
1.39
9.00
15
0.38
1.37
3.64
110
CB
102
2.0
24.00
0.60
0.33
0.33
10
0.012
0.60
0.11
5.00
5.00
7.03
1.39
9.00
15
0.38
1.37
3.64
111
CB
103
2.0
24.00
0.60
0.35
a0.3510
0.012
0.60
0.11
5.00
5.00
7.03
1.48
9.20
15
0.40
1.41
3.71
112
CB
104
2.0
24.00
0.60
0.40
0.40
10
0.012
0.60
0.11
5.00
5.00
7.03
1.69
9.67
15
0.44
1.53
3.81
122
123
124
125
114
116
116
117
118
108
126
CB
CB
CB
CB
CB
CB
CB
DCB
CB
CB
DI
123
124
125
114
116
117
117
118
108
81
125
2.1
2.1
2.0
2.3
2.0
2.0
2.0
5.6
5.9
6.3
2.0
163.57
63.5
24.00
168.20
99.03
09.8
109.80
55.38
24.00
29.04
33.91
0.60
3.02
0.60
2.55
0.73
0.55
0.55
0.50
0.50
0.50
0.60
0.64
0.29
0.23
0.16
0.32
0.28
0.28
0.44
0.21
0.18
0.44
0.44
0.49
0.33
0.34
0.64
0.64
0.93
1.16
1.76
2.72
3.37
3.99
5.07
5.28
5.46
0.44
10
10
10
10
10
10
10
10
10
10
10
0.012
0.012
0.012
0.012
0.012
0.012
0.012
0.012
0.012
0.012
0.012
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.09
0.31
0.08
0.29
0.25
0.24
0.28
0.14
0.06
0.07
0.14
5.00
5.09
5.40
5.49
5.77
6.03
6.26
6.54
6.68
6.74
5.00
5.00
7.03
2.70
11.54
15
0.61
1.96
4.40
5.09
6.91
3.86
9.74
15
0.44
1.53
8.40
5.40
5.49
6.91
4.81
1474
15
0.44
2.53
4.70
94
6.91
7.30
12.77
15
0.75
2.32
9.69
5.77
6.03
6.26
6.54
6.68
6.74
6.79
6.67
6.67
6.55
6.55
6.55
11.08
13.49
15.98
19.94
20.76
21.47
18.00
20.32
22.84
25.27
25.66
25.98
24
24
24
30
30
30
1.49
1.93
2.46
2.95
3.08
3.14
3.01
3.71
4.556.75
4.71Fj,
4.71.75
4.79.85
7.44
7.00
7.50
5.00
7.03
1.86
10.03
15
0.47
1.61
3.92
113
CB
114
2.0
24.00
0.60
0.49
0.49
10
0.012
0.60
0.10
5.00
5.00
7.03
2.07
10.44
15
0.50
1.69
4.10
0.60
0.09
5.00
119
DCB
117
2.0
24.00
0.60
0.64
0.64
10
0.012
5.00
7.03
2.70
11.54
15
0.61
1.96
4.40
120
CB
116
2.0
24.07
0.60
0.34
0.34
10
0.012
0.60
0.11
5.00
5.00
7.03
1.43
9.10
15
0.40
1.41
3.61

PROJECT NAME:
THE COURTYARDS ON LAWYERS ROAD
YARBROUGH-WILLIAMS & HOULE, INC.
Planning • Surveying • Engineering
REV.
8/27/2019
STORM DRAINAGE CALCULATIONS
P. O .BOX11
7007
REV.
VERSION 7.26.13
CHARLOTTE, N.C. 28241
DATE:
JANUARY 15, 2019
Phone: [phone]
REV.
REV.
Fax: [phone]
FROM
STRUCTURE
STRUCTURE
TYPE
TO
STRUCTURE
PIPE
COVER
AT STRUCT.
OUTPUT FOR SUBMITTAL
SURFACE LATERAL DRAINAGE DESIGN RUNOFF SECTION ACCUM. Tc
LENGTH SLOPE DRAINAGE PIPES AREA FREQUENCY MANNING'S COEFF. FLOW TIME FLOW TIME USED
FEET % AREA AREA TOTAL 10/25/50/100 n C MINUTES MINUTES MINUTES
RAINFALL
INTENSITY
10,25,50,100
RUNOFF
Q(CFS)
FES / HW
Q MAX
HW/D: 1.2
PIPE PIPE AREA WETTED DESIGN
DIAMETER DIAMETER OF PERIMETER VELOCITY
REQUIRED DESIGNED FLOW (SF) FT FPS
9.00 15 0.38 1.37 3.64
24.00
0.60
0.33
0.33
10
0.012
0.60
121
CB
El
2.0
0.11
5.00
5.00
7.03
1.39
133
133
134
C
C B
CB
135
1.2
1.6
29.97
61.58
49.58
4.14
0.60
0.60
5.18
0.66
0.56
0.36
5.18
6.20
6.76
10
10
10
0.012
0.012
0.012
0.60
0.60
0.60
0.04
0.15
0.12
26.60
26.64
26.79
26.60
26.64
26.79
3.89
3.89
3.89
12.08
14.46
15.76
17.90
14.09
21.65
22.36
24
24
24
0.94
2.20
2.35
2.1412.82
4.14
6.57
4.40
6.71
136
CB
133
2.0
113.48
0.60
0.36
0.36
10
0.012
0.60
0.51
5.00
5.00
7.03
1.52
9.30
15
0.41
1.46
3.68
138
CB
42
2.0
109,40
0.59
0.30
0.30
10
0.012
0.60
0.51
5.00
5.00
7.03
1.27
8.70
15
0.35
1.30
3.58
140
DDI
141
1.4
193.69 1
0.50
7-15-1-7.15
10
0.012
0.60
0.53
37.20
37.20
3.27
14.03
22.15
24
2.31
4.33
6.07

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NOT 005 i ti. 001 U5 02 OT S f
Ol I I. III... .. ., e r•"� ....1
3
Z
aas • 0 e , ,, vM„ , _

P. O .BOX 7007
CHARLOTTE, N.C. 28241
Phone: [phone] YARBROUGH-WILLIAMS & HOULE, INC.
Fax: [phone] Planning • Surveying • Engineering
PROJECT NAME:
THE COURTYARDS ON LAWY
DATE: JANUARY 15, 2019
NEW YORK STANDARDS RIP RAP APRON NOMOGRAPH [ Tw < 0.5(Do) ]
Rip Rap For Inlet Protection
RIP RAP APRON DESIGN
MINIMUM RIP RAP
RIP RAP
OUTLET
STRUCTURE
VEL.
APRON
RIP RAP
DEPTH (IN)
FLOW
NO.
FT/SEC
DIMENSIONS
D 50 (IN)
W/ FABRIC
CFS
WIDTH
X
LENGTH
1
R.R.F.I.P.
11
7.8
23.0
X
20.0
9.0
13.5
38.0
12
R.R.F.I.P.
25B
6.4
18.5
X
16.0
6.0
10.0
15.7
28
4.6
11.3
X
10.0
6.0
10.0
3.3

Phone: [phone] YARBROUGH-WILLIAMS & HOULE, INC.
Fax: [phone] Planning • Surveying • Engineering
PROJECT NAME : THE COURTYARDS ON LAWY
DATE. JANUARY 15, 2019
NEW YORK STANDARDS RIP RAP APRON NOMOGRAPH [ Tw < 0.5(Do) ]
R.R.I.F.P = Rip Rap For Inlet Protection
RIP RAP APRON DESIGN
MINIMUM RIP RAP RIP RAP OUTLET
STRUCTURE VEL. APRON RIP RAP DEPTH (IN) FLOW
NO. FT/SEC DIMENSIONS D 50 (IN) W/ FABRIC CFS
WIDTH X LENGTH
43 8.5 25.5 X 22.0 9.0 13.5 51.4

Phone: [phone] YARBROUGH-WILLIAMS & HOULE, INC.
Fax: [phone] Planning • Surveying • Engineering
PROJECT NAME: i THE COURTYARDS ON LAWY
DATE : JANUARY 15, 2019
NEW YORK STANDARDS RIP RAP APRON NOMOGRAPH [ Tw < 0.5(Do) ]
R.R.I.F.P = Rip Rap For Inlet Protection
RIP RAP APRON DESIGN
MINIMUM RIP RAP RIP RAP OUTLET
STRUCTURE VEL. APRON I RIP RAP DEPTH (IN) FLOW
NO. FT/SEC DIMENSIONS D 50 (IN) W/ FABRIC CFS
WIDTH X LENGTH
86 9.5 30.0 X 26.0 12.0 18.0 80.5
90 R.R.F.I.P.

Phone: [phone] YARBROUGH-WILLIAMS & HOULE, INC.
Fax: [phone] Planning a Surveying a Engineering
PROJECT NAME :
THE COURTYARDS ON LAWY
DATE: JANUARY 15, 2019
NEW YORK STANDARDS RIP RAP APRON NOMOGRAPH [ Tw < 0.5(Do) ]
R.R.I.F.P =Rip Rap For Inlet Protection
RIP RAP APRON DESIGN
MINIMUM RIP RAP
RIP RAP
OUTLET
STRUCTURE
VEL.
APRON
RIP RAP
DEPTH (IN)
FLOW
NO.
FT/SEC
DIMENSIONS
D50(IN)
W/FABRIC
CFS
WIDTH
X
LENGTH
132
R.R.F.I.P.
135
6.7
16.0
X
14.0
6.0
10.0
15.8
141 1
6.1
16.0
X
14.0
6.0
10.0
14.0

SPREAD CALCULATIONS

INLET SPREAD CHART ,`.iC�`�
Version 9. SPREAD
7.12
730 Windsor Oak Ct.
VGK _;, =r" Charlotte, NC 28273
Project Parameters YARBROUGH-WILLIAMS & HOULE, INC. Phone: [phone]
Intensity: 4.00 Planning • Surveying • Engineering Fax: [phone]
c' 0.60
Crown: 0.0208 Input 0.0208 or 0.0313 = input cells
VGK I Project Name: THE COURTYARDS ON LAWYERS ROAD Date: FEB. 3, 2019
Inlets on Slope
INLET
DRAINAGE
SLOPE
BYPASS
TYPE
SURFQ
BYPASS
SURFQ
INLET
BYPASS
SLOPE
ARFAAC.
LONG. o
TO INLET#
INLET
K
SUB
RECEIVED
TOTAL
Qcap
QSFNT
TRANS
n
SPREAD
REMARKS
0.00
0.0208
0.016
65
0.40
1.78
100
S
24
0.96
0.96
0.79
0.17
6.2
100
0.32
1.18
101
S
21
0.77
0.17
0.93
0.78
0.16
0.0208
0.016
6.6
101
0.20
1.18
102
S
21
0.48
0.16
0.64
0.61
0.03
0.0208
0.016
5.8
109
0.33
1.18
110
S
21
0.79
0.00
0.79
0.70
0.09
0.0208
0.016
6.2
102
0.32
1.18
103
S
211
0.771
0.03
0.79
0.701
0.09
0.0208
0.0161
6.3
110
0.33
1.18
Ill
S
21
0.79
0.09
0.88
0.75
0.13
0.0208
0.0161
6.5
103
0.49
1.18
104
D
21
1.18
0.09
1.27
L65
0.00
0.0208
0.0161
7.5
111
0.35
1.18
112
S
21
0.84
0.13
0.97
0.80
0.18
0.0208
o0161
6.8
104
0.47
1.18
105
S
21
1.13
0.00
1.13
0.87
0.25
0.0208
0.016
7.1
112
0.40
1.18
107
S
21
0.96
0.18
1.14
0.88
0.26
0.0208
0.016
7.2
105
0.29
1.18
106
S
21
0.70
0.25
0.95
0.78
0.17
0.0208
0.016
6.7
106
0.301
2.39
1191
S
27
0.72
0.17
0.89
0.77
0.11
0.0208
0.016
5.7
107
0.531
2.39
119
D
27
1.271
0.26
1,531
1.91
0.00
0.0208
0.016
7.0
78
0.50
L00
79
S
21
L201
0.00
1.20
0.96
0.24
0.0208
0.016
7.5
92
0.32
Loo
80A
S
21
0.77
0.06
0.83
0.76
0.07
0.0208
0.016
6.6
79
0.09
1.00
80
S
21
0.22
0.24
0.46
0.53
0.00
0.0208
0.016
5.3
80
0.19
1.00
119
S
21
0.46
0.00
0.46
0.52
0.00
0.0208
0.016
5.2
80A
0.24
1.00
117
S
21
0.58
0.07
0.65
0.65
0.00
0.0208
0.016
6.0
122
0.64
4.00
125
S
33
1.54
0.00
1.54
1.14
0.40
0.0208
0.016
6.4
123
0.29
4.00
1241
S
33
0.70
0.00
0.70
0.69
0.00
0.0208
0.016
4.7
-
125
0.161
3.00
114
S
301
0.38
0.40
0.78
0.74
0.04
0.0208
0.016
5.2
124
0.23
3.00
113
S
301
0.55
0.00
0.55
0.60
0.00
0.02081
0.016
4.6
114
0.47
2.00
115
S
271
1.13
0.04
1.17
0.97
0.20
0.0208
0.0161
6.5
113
0.49
2.00
121
S
271
1.18
0.00
1.18
0.98
0.20
0.0208
0.016
6.6
115
0.32
1.00
116
S
211
0.77
0.20
0.96
0.83
0.13
0.0208
0.016
6.9
121
0.33
L00
120
S
211
0.79
0.20
0.99
0.85
0.14
0.0208
0.016
7.0
116
0.28
1.00
117
S
21
0.67
0.13
0.80
0.74
0.06
0.0208
0.016
6.5
120
0.34
1.00
1191
S
21
0.82
0.14
0.961
0.83
0.13
0.0208
0.016
6.9
118
0.211
1.20
117
S
21
0.50
0.00
0.50
0.53
0.00
0.0208
0.016
5.3
108
0.18
1.20
117
S
21
0.43
0.00
0.43
0.481
0.00
0.0208
0.016
5.0
92A
0.34
1.00
92
S
21
0.82
0.00
0.82
0.75
O.061
0.0208
0.0161
6.5
94
0.11
1.56
96
S
24
0.26
0.00
0.26
0.37
0.00
0.0208
0.016
3.9
83
0.10
L56
84
S
241
0.24
0.00
0.24
0.35
0.00
0.0208
0.016
3.8
96
0.44
1.31
98
S
211
1.06
0.00
1.06
0.81
0.24
0.0208
0.016
6.8
84
0.11
1.31
991
S
21
0.26
0.00
0.261
0.34
0.00
0.0208
0.016
4.1
98
0.34
1.06
136
S
21
0.82
0.24
1.06
0.87
0.19
0.0208
0.016
7.1
99
0.14
1.06
134
S
21
0.34
0.00
0.34
0.42
0.00
0.0208
0.016
4.6
136
0.36
1.06
133
S
21
0.86
0.19
1.06
0.87
0.1
081
0.016
7.1
Inlets at Sag
INLET
DRAINAGE
SURF Q
BYPASS Q
SURF Q
SLOPE
SINGLE = "S"
DEPTH
#
AREA
SUB
RECEIVED
TOTAL
TRANS.
DOUBLE-D"
(D)
SPREAD
REMARKS
0.44
1.06
0.06
1.11
0.0208
D
0.11
5.05
ffl
- 0.64
L54
0.24
1.78
0.0208
D
0.14
6.89
0.66
1.58
0.19
1.77
0.0208
D
O.I4
6.88
0.56
1.34
0.00
34
0.0208
S
0.15
Z26

INLET SPREAD CHART ,`'C�`��
Version 9. SPREAD
7.12
730 Windsor Oak Ct.
Charlotte, NC 28273
Project Parameters YARBROUGH-WILLIAMS & HOULE, INC. Phone: [phone]
Intensity: 4.00 Planning • Surveying • Engineering Fax: [phone]
c: 0.60
Crown: 0.0208 Input 0.0208 or 0.0313 = input cells
WKD Project Name: I THE COURTYARDS ON LAWYERS ROAD Date: FEB. 3, 2019
Inlets on Slope
INLEI DRAINAGE
SLOPE
BYPASS
TYPE
SURF
BYPASS
SURF
INLET
BYPASS
SLOPE
-
AREA.Ac
LONG "
TOINLET ii
INLET
K
SUB
RECEIVED
TOTAL
Qcap
QSENT
TRANS
n
SPREAD
REMARKS
66
0.37
I78
48
S
24
0.89
0.00
0.89
0.76
0.13
0.0208
0.016
6.0
32
0.34
106
33
S
21
0.82
0.00
0.82
0.74
0.08
0.0208
0.016
6.4
31
0.39
1.06
33
S
21
0.94
0.00
0.94
0.80
0.13
0.0208
0.016
6.8
30
0.50
1,08
33
S
21
1.20
0.00
1.20
0.93
0.27
0.0208
0.016
7.4
29
0.39
1.08
641
S
211
0.94
0.00
0.941
0.80
0.141
0.0208
0.0161
6.8
331
0.08
1.08
34
S
21
0.19
0.48
0.671
0.65
0.02
0.0208
0.016
6.0
64
0.35
1.08
63
S
21
0.84
0.14
0.98
0.82
0.16
0.0208
0.016
6.9
34
0.14
1.08
35
S
21
0.34
0.02
0.36
0.44
0.00
0.0208
0.016
4.7
63
0.47
1.08
61
D
21
L13
0.16
L28
1.70
0.00
0.0208
0.016
T6
61
0.40
1.08
62
S
21
0.96
0.00
0.96
0.81
0.15
0.0208
0.016
6.8
35
0.29
1.08
36
S
21
0.70
0.00
0.70
0.66
0.03
0.0208
0.016
6.1
62
0.351
1.08
60
S
21
0.84
0.15
0.99
0.83
0.16
0.0208
0.016
6.9
36
0.531
1.08
37
S
211
1.27
0.03
1.30
0.98
0.32
0.0208
0.016
7.7
60
0.32
1.08
59
D
21
0.77
0.16
0.93
1.39
0.00
0.0208
0.016
6.7
37
0.19
L08
38
S
21
0.46
0.32
0.78
0.71
0.07
0.0208
0.016
6.3
59
0.49
1.08
58
D
21
1.18
0.00
1.18
1.61
0.00
0.0208
0.016
7.4
38
0.18
1.08
41
S
21
0.43
0.07
0.50
0.54
0.00
0.0208
0.016
5.3
58
0.46
L08
42
D
21
1.10
0.00
1.10
1.55
0.00
0.0208
0.016
7.2
138
0.30
0.89
42
S
19
0.72
0.06
0.78
0.691
0.10
0.02081
0.016
6.6
55
0.11
1.03
41
S
21
0.26
0.00
0.26
0.37
0.00
0.0208
0.016
4.2
54
0.331
1.03
138
S
21
6.79
0.00
0.79
0.73
0.06
0.0208
0.016
6.4
48
0.39
1.00
56
D
21
0.94
0.13
1.07
1.56
0.00
0.0208
0.016
7.2
49
0.31
1.00
50
S
21
0.74
0.00
0.74
0.71
0.03
0.0208
0.016
6.3
56
0.49
1.00
57
D
21
1.18
0.00
L18
1.65
0.00
0.0208
0.016
7.5
50
0.48
1.00
51
D
21
1.15
0.03
1.19
1.66
0.00
0.0208
0.016
7.5
57
0.48
1.00
53
S
21
1.15
0.00
1.15
0.93
0.22
0.0208
0.016
7.4
51
0.48
1,00
521
S
21
1.15
0.00
1.15
0.93
0.22
0.0208
0.016
7.4
53
0.31
1.00
41
S
21
0.74
0.22
0.96
0.83
0.13
0.0208
0.016
6.9
52
0.261
1.00
41
S
21
0.62
0.22
0.84
0.77
0.08
0.0208
0.016
6.6
67
0.33
1.00
71
S
21
0.79
0.00
0.79
0.74
0.05
0.0208
0.016
6.4
68
0.32
1.00
69
S
21
0.77
0.00
0.77
0.72
0.04
0.0208
0.016
6.4
69
0.28
1.00
70
S
21
0.671
0.04
0.72
0.691
0.02
0.0208
0.0161
6.2
70
0.28
1.00
73
S
21
0.67
0.02
0.70
0.68
0.02
0.02081
0.016
6.1
71
0.35
1.00
721
S
21
0.84
0.05
0.89
0.80
0.10
0.0208
0.016
6.7
72
0.23
L00
77
S
21
0.55
0.10
0.65
0.65
0.00
0.0208
0.016
6.0
73
0.461
1.00
77
S
21
1.10
0.021
1.12
0.92
0.20
0.0208
0.016
7.3
74
0.10
1.04
77
S
21
0.24
0.00
0.24
0.35
0.00
0.0208
0.016
4.1
75
0.33
1.04
76
D
21
0.79
0.00
0.79
1.27
0.00
0.0208
0.016
6.4
91
0.35
1.36
76
D
21
0.84
0.00
0.84
1.22
0.00
0.0208
0.016
6.2
Inlets at Sag
INLET
DRAINAGE
SURF Q
BYPASS Q
SURF Q
SLOPE
SINGLE _ "S"
DEPTH
#
AREA
SUB
RECEIVED
TOTAL
TRANS.
DOUBLE="D"
(D)
SPREAD
REMARKS
41
0.45
1.08
0.21
1.29
0.0208
S
0.15
7.05
42
0.65
1.56
0.10
1.66
0.0208
D
0.14
6.57
76
0.82
1.97
0.00
1.97
0.0208
D
0.15
7.38
77
0.67
L61
0.20
1.81
0.0208
D
0.15
6.98

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p

EROSION CONTROL
SKIMMER BASIN
CALCULATIONS

P. O .BOX 7007
YARBROUGH-WILLIAMS & HOULE, INC.
Planning • Surveying • Engineering
CHARLOTTE, N.C. 28241
Phone: [phone]
Fax: [phone]
PROJECT:
THE COURTYARDS ON LAWYERS ROAD
DATE:
February 27, 2019
SKIMMER BASIN DESIGN - MECK COUNTY STD. 30.02A, STATE STD. DETAIL # 6.64, BAFFLE SPACING 30.19
SKIMMERARM
FAIRCLOTH
SKIMMER
REQUIRED
SURFACE AREA
REQUIRED
STORAGE
ASSEMBLY
SKIMMERARM
SKIMMER
SKIMMER
I
theoritical
BASIN
DRAINAGE
DENUDED
Q10
SURFACE AREA
PROVIDED
STORAGE
VOLUME (CF)
TOP (Min.) BOTTOM (Min.)
DEPTH (FT)
DIA. (IN)
ASSEMBLY
SIZE (IN.)
ORIFICE
HEAD AT
SPILLWAY
HEAD (FT)
TOP OF
SKIMMER
spillway
Tc
NO
AREA (AC.)
AREA (AC.)
(cfs)
(sf)
(sf)
VOL. (CF)
PROVIDED
W(ft) X L(ft) W(ft) X Lilt)
(H)
LENGTH (FT)
DIA. (IN.)
ORIFICE
Z (FT)
WIDTH (L) (FT)
T (FT)
W (FT)
AT SPILLWAY
DAM ELEV,
capacity
Width
cfs
ft
min
3
4.26
3.67
17.97
6839.82
8353.00
6,606
13.660
38
X
190
27
X
178
2
1.5
6.00
2.00
1.60
0.13
5.0
10
3.0
10.0
0.5
683
0.053
10
5
5
4.12
4.12
17.38
5647.90
6841.00
7,416
11,869
78
X
89
65
X
77
2
1.6
6.00
2.00
1.70
0.13
5.0
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0.046
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6
1.09
1.09
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1494.23
3727.00
1,962
6,099
59
X
61
47
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6.00
1.50
0.90
0.00
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0.024
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7 1
2.71
2.71
11.43
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4734.00
4,878
7.525
42
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101
31
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1.5
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1.50
1.50
0.00
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3.0
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0.6
682
0.029
10
6

SKIMMER BASIN #3
Calculate Skimmer Size
Basin Volume in Cubic Feet 6,606 Cu.Ft Skimmer Size 2.0 Inch
Days to Drain* 3 Days Orifice Radius 0.8 Inch[es]
Orifice Diameter 1.6 Inch[es]
In NC assume 3 days to drain
Estimate Volume of Basin Length width
Top of water surface in feet Feet VOLUME 0 Cu. Ft.
Bottom dimensions in feet Feet
Depth in feet Feet

SKIMMER BASIN #5
Calculate Skimmer Size
Basin Volume in Cubic Feet 7,416 Cu.Ft Skimmer Size 2.0 Inch
Days to Drain" 3 Days Orifice Radius 0.8 Inch[es]
Orifice Diameter 1.7 Inch[es]
In NC assume 3 days to drain
Estimate Volume of Basin Length Width
Top of water surface in feet Feet VOLUME 0 Cu. Ft.
Bottom dimensions in feet Feet
Depth in feet Feet

SKIMMER BASIN #6
Calculate Skimmer Size
Basin Volume in Cubic Feet 1,962 Cu.Ft Skimmer Size 1.5 Inch
Days to Drain* 3 Days Orifice Radius 0.5 Inch[es]
Orifice Diameter 0.9 Inch[es]
In NC assume 3 days to drain
Estimate Volume of Basin Length width
Top of water surface in feet Feet VOLUME 0 Cu. Ft.
Bottom dimensions in feet Feet
Depth in feet Feet

SKIMMER BASIN #7
Calculate Skimmer Size
Basin Volume in Cubic Feet 4,878 Cu.Ft Skimmer Size 1.5 Inch
Days to Drain" 3 Days Orifice Radius 0.7 Inch[es]
Orifice Diameter 1.5 Inch[es]
'In NC assume 3 days to drain
Estimate Volume of Basin Length width
Top of water surface in feet Feet VOLUME 0 Cu. Ft.
Bottom dimensions in feet Feet
Depth in feet Feet

EROSION CONTROL
SEDIMENT BASIN
CALCULATIONS

P. O .BOX 7007
ymi
CHARLOTTE, N.C. 28241
Phone: [phone]
YARBROUGH-WILLIAMS HOULE, INC.
Fax: [phone]
&
SEDIMENT BASIN
DESIGN STATE
STD. DETAIL
S11, BAFFLE
SPACING 30.19
TOP (Min.) BOTTOM (Min.)
or" M'
TOTOPOFDAM

SEDIMENT BASIN #1
Calculate Skimmer Size
Basin Volume in Cubic Feet 57,096 Cu.Ft Skimmer Size 4.0 Inch
Days to Drain* 3 Days Orifice Radius 1.9 Inch[es]
Orifice Diameter 3.9 Inch[es]
In NC assume 3 days to drain
Estimate Volume of Basin Length width
Top of water surface in feet Feet VOLUME 0 Cu. Ft.
Bottom dimensions in feet Feet
Depth in feet Feet

SEDIMENT BASIN #2
Calculate Skimmer Size
Basin Volume in Cubic Feet 40,410 Cu.Ft Skimmer Size 4.0 Inch
Days to Drain* 3 Days Orifice Radius 1.6 Inch[es]
Orifice Diameter 3.3 Inch[es]
In NC assume 3 days to drain
Estimate Volume of Basin Length Width
Top of water surface in feet Feet VOLUME 0 Cu. Ft.
Bottom dimensions in feet Feet
Depth in feet Feet

EROSION CONTROL
TEMPORARY DITCH
CALCULATIONS

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ENGINEERING.com I Open Channel Flow Calculator
Page 1 of 1
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y
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Calculator
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-►
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Calculator
�+
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-+
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DIVERSION DITCH #1
Open -Channel Flow
This calculator uses Chezy and Manning's formula to calculate the wetted perimeter,
hydraulic radius, flow area, Chezy coefficient and flow velocity.
For experimental values of Manning's n factor, click here
Required Information
Enter the Slope:
0242
Enter the Channel Top
Width
9
(ft):
Enter the Channel Bottom
Width
13 1
Enter the Channel
(ft):
Height (ft):
Enter the Flow Depth (ft):
.27
Enter the n value:
.03
Results
The wetted perimeter is 4.707E ft The flow is 2.883 W/s
The flow area is 1.0287 ftZ The flow is 1294.112 gal/min
The hydraulic radius is 0.218E ft The velocity is �2 80304 ft/s
The C value is 38.546(
Calculate Reset
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ENGINEERING.com I Open Channel Flow Calculator
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Calculator
Atmospheric Calculator
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r
Calculator
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Calculator
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Calculator
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Converter
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Calculator
Oblique Flow Relations
-4
Calculator
Open -channel Flow
Calculator
Properties of Welds
Treated as Lines
Calculator
-{
Shaft Speed Calculator
Torque Transmitted by
.0
Clutch Calculator
-0
Water Pump Engineering
Back to
ENGINEERING.com
DIVERSION DITCH #2
Open -Channel Flow
This calculator uses Chezy and Manning's formula to calculate the wetted perimeter,
hydraulic radius, flow area, Chezy coefficient and flow velocity.
For experimental values of Manning's n factor, click here
Required Information
Enter the Slope:
0309
Enter the Channel Top
Width
43
(ft):
Enter the Channel Bottom
Width
1
Enter the Channel
(ft):
Height (ft):
Enter the Flow Depth (ft):
Fl—.587
Enter the n value:
03
Results
The wetted perimeter is 11.50E ft The flow is 92.918C W/s
The flow area is 10.981 ftZ The flow is 41701.61' gal/min
The hydraulic radius is K9541 ft The velocity is F8.4 617 11 ft/s
The C value is [49.279
Calculate Reset
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ENGINEERING.com I Open Channel Flow Calculator
Page 1 of I
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Air Flow Conversion
Calculator
-e
Atmospheric Calculator
�+
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y
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Calculator
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.4
Calculator
-0
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Calculator
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r
Converter
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Calculator
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Calculator
Open -channel Flow
Calculator
Properties of Welds
-►
Treated as Lines
Calculator
�►
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Torque Transmitted by
.�
Clutch Calculator
�t
Water Pump Engineering
Back to
ENGINEERING.com
DIVERSION DITCH #3
Open -Channel Flow
This calculator uses Chezy and Manning's formula to calculate the wetted perimeter,
hydraulic radius, flow area, Chezy coefficient and flow velocity.
For experimental values of Manning's n factor, click here
Required Information
Enter the Slope:
0149
Enter the Channel Top
Width
40
(ft):
Enter the Channel Bottom
Enter the Channel
Width (ft):
Height (ft):
L' I
Enter the Flow Depth (ft):
11.295
Enter the n value:
.03
Results
The wetted perimeter is 10.31E ft The flow is 43.671 i ft3/s
The flow area isF8.31711 ft2 The flow is F1 659 711 gal/min
The hydraulic radius is ft The velocity is 5. 0.806C 2508 11 ft/s
The C value is 47. 113Z
Calculate Reset
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ENGINEERING.com I Open Channel Flow Calculator Page I of I
DIVERSION DITCH #4
Other Calculators Open -Channel Flow
Air Flow Conversion
Calculator
This calculator uses Chezy and Manning's formula to calculate the wetted perimeter,
hydraulic radius, flow area, Chezy coefficient and flow velocity.
-►
Atmospheric Calculator
For experimental values of Manning's n factor, click here
�-►
Block Wall Calculator
Concrete Column
Required Information
y
Calculator
Enter the Slope:
1.0361
Enter the Channel Top 9
Width (ft):
.+
Concrete Volume
Calculator
Enter the Channel Bottom
Width
13
Enter the Channel
(ft):
Height (ft):
-4
Energy Conversion Calculator
Enter the Flow Depth (ft):
3$2
Enter the n value: .03
Isentropic Flow Relations
Calculator
Results
The wetted perimeter is 5.415S ft
The flow is 6.58441E ft-/s
Laser Real Time Unit
The flow area is 1.5837 ftZ
The flow is 2955.115' gal/min
Converter
The hydraulic radius is 0.2924 ft
The velocity is 4.1574E ft/s
y
Normal Flow Relations
Calculator
The C value is 40.4631E
y
Oblique Flow Relations
Calculator
Calculate
Reset
Open -channel Flow
Calculator
Properties of Welds
-4
Treated as Lines
Calculator
�►
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Torque Transmitted by
Clutch Calculator
�+
Water Pump Engineering
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ENGINEERING.com I Open Channel Flow Calculator Page 1 of 1
DIVERSION DITCH #5
Other Calculators Open -Channel Flow
Air Flow Conversion
Calculator
This calculator uses Chezy and Manning's formula to calculate the wetted perimeter,
hydraulic radius, flow area, Ch6zy coefficient and flow velocity.
�
Atmospheric Calculator
For experimental values of Manning's n factor, click here
�►
Block Wall Calculator
Required Information
Concrete Column
Calculator
Enter the Slope:
1.0177
Enter the Channel Top 15
Width (ft):
Concrete Volume
Calculator
Enter the Channel Bottom
Width
(
133
Enter the Channel
(ft):
Height (ft):
Energy Conversion
Calculator
Enter the Flow Depth (ft): 11.24
Enter the n value: .03
.r
Isentropic Flow Relations
Calculator
Results
The wetted perimeter is 10.842 ft
The flow is 46.1974 ft3/s
y
Laser Real Time Unit
The flow area is 8.3327 ftZ
The flow is 20733.43 gal/min
Converter
The hydraulic radius is.768� ft
The velocity is 5.5440` ftls
-4
Normal Flow Relations
Calculator
The C value is
47.534`.
Oblique Flow Relations
Calculate
Reset
Calculator
Open -channel Flow
Calculator
Properties of Welds
-n
Treated as Lines
Calculator
-►
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Torque Transmitted by
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�+
Water Pump Engineering
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DETENTION SUMMARY

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WET POND #1
CALCULATIONS

ywi
YARBROUGH-WILLIAMS & HOULE, INC.
Planning • Surveying • Engineering
Wet Pond Calculations P. O .BOX 7007
References: NCDENR DWQ 8MP Design Manual CHARLOTTE, N.C. 28241
Phone: [phone]
Date: 4/262019 Fax: [phone]
PROJECT: COURTYARDS ON LAWYERS ROAD
Base Data
Site Area Post = Total Drainage Area (Ac) = 31.72 ac
Pre-dev. Drainage Area ( Ac) 9.58 ac
Post Dev. Impervious Area (Ac)
Measured Impervious Area - 41
Soils Tvoe& Cecil, Enon
Zoning: Residential
Hydrologic Data
Pre - CN
Land Use
Soil Type
Hydrologic Group
CN
wei hted CN
4.71
Woods
B
55
27.04
1.97
Woods
C
70
14.39
2.90
Woods
D
77
23.31
9.58
Pre
CNpo,t
65
Post - CN
Acreage
Land Use
Soil age
Hydrologic Group
CN
(weighted) CN
12.88
Bld / vt
98
39.79
3.48
Grass
B
61
6.69
7.26
Grass
C
74
1894
8.10
Grass
D
80
20.43
31.72
Post CN84
CN 84

Steps 1 Determine if the development site and conditions are appropriate for the use of a
Wet Pond and consider any site -specific design considerations.
Step 2 Compute Water Quality Volume (WQv)
( WQv for the Goose Creek Watershed shall be the difference in the storm water runoff from the pre -development and post -development conditions
for the 1-year, 24 hour storm.
Step 3
Pre -development 1-year, 24 hr storm volume =
Post -development 1-year, 24 hr stone volume =
DIFFERENCE IN 1 YEAR STORM VOLUME =
AT ELEV. 663.13 THE VOLUME TREATED IS =
Compute Site Hydrologic Input Parameters
Using SCS hydrologic procedures and/or computer models the following data can
be determined for the development site.
HYDROLOGIC INPUT DATA
11,412
135689
124,277 cf required for treatment
135,689 cf RELEASED GRADUALLY DURING 120 HOURS
WITH A PEAK RATE OF Approx. 1.02 cfs
Condition
Area
CN
4 (hours)
t, (min)
Pre dev
9.58
ac
65
0.47
28.2
Post dev
31.72
ac
84
0.24
14.2

Results of Preliminary Hydrologic Calculations
(From Computer Model Results Using SCS Hydrologic Procedures)
Condition Runoff
Ql.Y,
Q2.Mr
Q10-
Q25y,,,
050,,
cis
cfs
cfs
cfs
cfs
Pre -development Flow
1.70
1.67
8.39
12.48
15.95
Post Development Detained
1.02
1.04
3.85
4.60
5.12
The facility would require 2.85 ac-ft for
Water Quality Volume (WQv) treatment
Q100.r,,,
cfs
19.18
10.12
Perm Pool Storage -Elevation Data
Elevation
Area (9f)
Area (ac)
Ht (ft)
Inc. Vol (ac-ft)
Acc. Vol Jac-ft)
Acc. Vol (cf)
652.5
11000.0
0.253
0.0
0.000
0.000
0
653
11500.0
0.264
0.5
0.000
0.000
0
654
12400.0
0.285
1.5
0.274
0.274
11950
656
14400.0
0.331
3.5
0.615
0.890
38750
658
16500.0
0.379
5.5
0.709
1.599
69650
660
18800.0
0.432
7.5
0.810
2.409
104950
660.5
21500.0
0.494
8.0
0.231
2.641
115025
Permanent Pool Volume
Depth =
8.00
ft
PPE Elevation =
660.5
Shelf Elevation =
660
Bottom Elevation =
651.5
Bottom Elevation -1 =
652.5
PPE Surface Area =
21,500
sf
Shelf Area = 1
18,800
sf
Surface Area Bot Pond =
11,000
sf
Permanent Pool Volume =
115,025
cf
Vshelf
762.5 cf
Avg. Depth = 6.08 It
Using avg = 6.08 and 41 % impervious cover, Min. SA/DA Ratio From State Table 1) 10.9%
Surface area required = 12434 sf
Surface area provided = 21500 at
Step 4 Size Flow Diversion Structure - No Diversion Structure
Step 5 Compute Release Rates for Water Quality Control
Compute the release rate for water quality control.
The water quality control volume (WQv) is to be released over a 2-day
duration beyond the center of rainfall (48 hours plus 3 hours) period.
Release Rate = 2.85 ac-ft X 43560 ft'/acre / (51 hrs X 3600 sec/hr)
0.677 cfs

Step 6
Compute Forebay Chamber Volume
The forebay chamber storage area above the filter media must be sized to hold 20
percent of the water quality volume
Required Forebay Chamber Volume = 115025.00 cf x (0.20) _
= 23005 cf = 0.53 ac-ft
Proposed Forebay Chamber Volume = 22175 d
Forebay Chamber
Store e-Elevation Data
Elevation
Areas
Area ac
Ht ft
Inc. Vol ac-ft
Acc. Vol ac-ft
Acc. Vol
655
2200.0
0.051
0.0
0.000
0.000
0.0
656
2800.0
0.064
1.0
0.057
0.057
2500.0
658
4000.0
0.092
3.0
0.156
0.213
9300.0
660
5600.0
0.129
5.0
0.220
0.434
18900.0
660.5
7500.0
0.172
5.5
0.075
0.509
22175.0
Step 7 Develop Water Quality Storage -Elevation Table
Permanent Pond Surface Elev. = 1 660.5
Water Quality Storage -Elevation Data
Elevation
Area (sf)
Area ac
Ht ft
Inc. Vol ac-it
Acc. Vol ac-ft
Acc. Vol c
660.5
29000.0
0.666
0.0
0.000
0.0
661
34000.0
0.781
0.5
0.362
0.362
15750.0
663
41000.0
0.941
2.5
1.722
2.083
90750.0
665
48000.0
1.102
4.5
2.043
4.126
179750.0
667
55000.0
1.263
6.5
2.365
6.491
282750.0
669
63000.0
1.446
8.5
2.709
9.200
400750.0
Step 8 Route Runoff Hydrographs through Wet Pond
Route all of the appropriate runoff hydrographs through the wet pond facility with the following goals:
Release water quality volume (WQV) within 48-120 hours
Step 9 Water Quality Release Orifice Sizing
A=
35000.0
sf - avg.
hi=j
2.50
C=
0.6
9=
32.2
t =
172800 sec = 48 hrs
a =
0.13302
Dia =
5 in Use 5 inch

Step 10 Calculation for Anti -flotation Concrete Anchor
A. Bouyancy
Elevation
Top of Dam =
669.00
Top of Box =
667.75
Pond Shelf =
661.00
Bottom of Box =
659.30
Box Area =
25
sf
Anchor Area =
56.25
sf 7.5' x 7.5'
Anchor thickness =
1
Area of Riser - Inside 16 sf / Outside 25 sf
V (wetwell) = V (riser) + V(base footing) _ (667.75-659.3) X (25) + 1.0 X (56.25) = 268
Floatation = V(wetwell) x V(water) = 267.5 cf x 62.4 Ib/cf = 16692
B. Counter Bouyancy
Conc. Wt. _ {V(conc. riser) + V(conc. Footing)) x Conc. Unit Wt. _
((25-16) x (667.75-659.30) + (56.25 x 1)) x 150 Ibs/cf = 19845
Earth Wt. = V(Earth) X Earth Unit Wt. _
(56.25-25) X 1.2X 115 LBS/CF = 4313
Anti -Floatation = 24158 Ibs
C. Safety Factor = 1.4 1.1 required by NCDENR for Anti-floation

WET POND #1
HYDROCAD REPORT

is
PRE DRAINAGE AREA
#1
Subcat Reach POn Link Routing Diagram for Wet Pond # 1
Prepared by Microsoft, Printed 8/27/2019
HydroCAD® 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC

Wet Pond # 1 Charlotte 24-hr 1-yr 1 yr Rainfall=2.58"
Prepared by Microsoft Printed 8/27/2019
HydroCAD® 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 2
Summary for Subcatchment 1S: PRE DRAINAGE AREA #1
Runoff = 1.70 cfs @ 12.37 hrs, Volume= 0.262 af, Depth= 0.33"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs
Charlotte 24-hr 1-yr 1 yr Rainfall=2.58"
Area (ac) CN Description
4.710 55 GROUP B
1.970 70 GROUP C
2.900 77 GROUP D
9.580 65 Weighted Average
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
20.2
150
0.0470
0.12
Sheet Flow, SHEET FLOW
Woods: Light underbrush n= 0.400 P2= 3.50"
4.7
250
0.0320
0.89
Shallow Concentrated Flow, SHALLOW CONCENTRATED
Woodland Kv= 5.0 fps
3.3
1,080
0.0300
5.40
43.24 Channel Flow, CHANNEL
Area= 8.0 sf Perim= 16.0' r= 0.50' n= 0.030
28.2 1,480 Total
Subcatchment 1S: PRE DRAINAGE AREA #1
Hydrograph
Runoff
Charlotte 24-hr 1-yr
1 yr Rainfall=2.58"
Runoff Area=9.580 ac
Runoff Volume=0.262 of
Runoff Depth=0.33"
LL I Flow Lenath=1.480'
CN=65
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)

Wet Pond # 1 Charlotte 6-hr 2-yr 2 yr Rainfall=2.28"
Prepared by Microsoft Printed 8/27/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 3
Summary for Subcatchment 1S: PRE DRAINAGE AREA #1
Runoff = 1.67 cfs @ 3.60 hrs, Volume= 0.175 af, Depth= 0.22"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs
Charlotte 6-hr 2-yr 2 yr Rainfall=2.28"
Area (ac) CN Description
4.710 55 GROUP B
1.970 70 GROUP C
2.900 77 GROUP D
9.580 65 Weighted Average
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
20.2
150
0.0470
0.12
Sheet Flow, SHEET FLOW
Woods: Light underbrush n= 0.400 P2= 3.50"
4.7
250
0.0320
0.89
Shallow Concentrated Flow, SHALLOW CONCENTRATED
Woodland Kv= 5.0 fps
3.3
1,080
0.0300
5.40
43.24 Channel Flow, CHANNEL
Area= 8.0 sf Perim= 16.0' r= 0.50' n= 0.030
28.2 1,480 Total
Subcatchment 1S: PRE DRAINAGE AREA #1
Hydrograph
0 Runoff
Charlotte 6-hr
2-yr
2yr Rai'nfa'll=2.28"
Runoff Area=9.580 ac
Runoff 'Volume=0.175 of
Runoff Depth=0.22"
Flow Length=1,480'
Tc=28.2 min
-1 CN=65
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)

Wet Pond # 1 Charlotte 6-hr 10-yr 10 yr Rainfall=3.72"
Prepared by Microsoft Printed 8/27/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 4
Summary for Subcatchment 1S: PRE DRAINAGE AREA #1
Runoff = 8.39 cfs @ 3.54 hrs, Volume= 0.695 af, Depth= 0.87"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs
Charlotte 6-hr 10-yr 10 yr Rainfall=3.72"
Area (ac) CN Description
4.710 55 GROUP B
1.970 70 GROUP C
2.900 77 GROUP D
9.580 65 Weighted Average
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
20.2
150
0.0470
0.12
Sheet Flow, SHEET FLOW
Woods: Light underbrush n= 0.400 P2= 3.50"
4.7
250
0.0320
0.89
Shallow Concentrated Flow, SHALLOW CONCENTRATED
Woodland Kv= 5.0 fps
3.3
1,080
0.0300
5.40
43.24 Channel Flow, CHANNEL
Area= 8.0 sf Perim= 16.0' r= 0.50' n= 0.030
28.2 1,480 Total
Subcatchment 1 S: PRE DRAINAGE AREA #1
Hydrograph
9
8.39 cfs
8 Charlotte 6-hr 10-yr
10 yr Rainfall=3.72"
Runoff Area=9.580 ac 6-Runoff Volume=0.695 of
5: Runoff Depth=0.87"
4 Flow Length=1,480'
Tc=28.2 m i n
3
CN=65
2-
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)
Runoff

Wet Pond # 1 Charlotte 6-hr 25-yr 25 yr Rainfall=4.38"
Prepared by Microsoft Printed 8/27/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 5
Summary for Subcatchment 1S: PRE DRAINAGE AREA #1
Runoff = 12.48 cfs @ 3.47 hrs, Volume= 1.003 af, Depth= 1.26"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs
Charlotte 6-hr 25-yr 25 yr Rainfall=4.38"
Area (ac) CN Description
4.710 55 GROUP B
1.970 70 GROUP C
2.900 77 GROUP D
9.580 65 Weighted Average
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
20.2
150
0.0470
0.12
Sheet Flow, SHEET FLOW
Woods: Light underbrush n= 0.400 P2= 3.50"
4.7
250
0.0320
0.89
Shallow Concentrated Flow, SHALLOW CONCENTRATED
Woodland Kv= 5.0 fps
3.3
1,080
0.0300
5.40
43.24 Channel Flow, CHANNEL
Area= 8.0 sf Perim= 16.0' r= 0.50' n= 0.030
28.2 1,480 Total
a
3 7
0
LL 6
5
Subcatchment 1S: PRE DRAINAGE AREA #1
Hydrograph
Charlotte 6-hr
25-yr
25 yr Rainfall=4.38"
Runoff Area=9.580 ac
Runoff 'Volume=1.003 of
Runoff Depth=1.26"
Flow Length=1480'
Tc=28.2 m i n
CN=65
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)
Runoff

Wet Pond # 1 Charlotte 6-hr 50-yr 50 yr Rainfall=4.92"
Prepared by Microsoft Printed 8/27/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 6
Summary for Subcatchment 1 S: PRE DRAINAGE AREA #1
Runoff = 15.95 cfs @ 3.45 hrs, Volume= 1.278 af, Depth= 1.60"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs
Charlotte 6-hr 50-yr 50 yr Rainfall=4.92"
Area (ac) CN Description
4.710 55 GROUP B
1.970 70 GROUP C
2.900 77 GROUP D
9.580 65 Weighted Average
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
20.2
150
0.0470
0.12
Sheet Flow, SHEET FLOW
Woods: Light underbrush n= 0.400 P2= 3.50"
4.7
250
0.0320
0.89
Shallow Concentrated Flow, SHALLOW CONCENTRATED
Woodland Kv= 5.0 fps
3.3
1,080
0.0300
5.40
43.24 Channel Flow, CHANNEL
Area= 8.0 sf Perim= 16.0' r= 0.50' n= 0.030
28.2 1,480 Total
Subcatchment 1S: PRE DRAINAGE AREA #1
Hydrograph
1 -
15.95 cfs
16: Charlotte 6-hr
15-
14 50-yr
13-
1250 yr Rainfall=4.92"
:
11 Runoff Area=9.580 ac
10
3 9,
Runoff Volume=1.278 of
rL $= Runoff Depth=1.60"
Flow Le
6.- ngth=1480'
5 Tc=28.2 m i n
4
3 CN=65
2_
1-
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)
� Runoff

Wet Pond # 1 Charlotte 6-hr 100-yr 100 yr Rainfall=5.34"
Prepared by Microsoft Printed 8/27/2019
HydroCAD@ 10.00-22 s/n 05047 ©2018 HydroCAD Software Solutions LLC Page 7
Summary for Subcatchment 1S: PRE DRAINAGE AREA #1
Runoff = 19.18 cfs @ 3.45 hrs, Volume= 1.504 af, Depth= 1.88"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs
Charlotte 6-hr 100-yr 100 yr Rainfall=5.34"
Area (ac) CN Description
4.710 55 GROUP B
1.970 70 GROUP C
2.900 77 GROUP D
9.580 65 Weighted Average
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
20.2
150
0.0470
0.12
Sheet Flow, SHEET FLOW
Woods: Light underbrush n= 0.400 P2= 3.50"
4.7
250
0.0320
0.89
Shallow Concentrated Flow, SHALLOW CONCENTRATED
Woodland Kv= 5.0 fps
3.3
1,080
0.0300
5.40
43.24 Channel Flow, CHANNEL
Area= 8.0 sf Perim= 16.0' r= 0.50' n= 0.030
28.2 1,480 Total
Subcatchment 1S: PRE DRAINAGE AREA #1
►4
19
18
17
16
15
14
13
N 12
11
0 10
LL
.. r . 774 77
- , 4 1 .0
Hydrograph
Charlotte 6-hr
100-yr
100 yr Rainfall=5.34"
Runoff Area=9.580 ac
Runoff Volume=1.504 of
Runoff Depth=1.88"
Flow Length=1,480'
Tc=28.2 m i n
CN=65
80 90 100 110 120 130 140 150 160 170
Time (hours)
Runoff

4S ) -0
POST WP # 1
Subcat Reach Pon Link
Wet Pond # 1

Wet Pond # 1 Charlotte 24-hr 1-yr 1 yr Rainfall=2.58"
Prepared by Microsoft Printed 8/27/2019
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Summary for Subcatchment 4S: POST WP # 1
Runoff = 45.27 cfs @ 12.12 hrs, Volume= 3.115 af, Depth= 1.18"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs
Charlotte 24-hr 1-yr 1 yr Rainfall=2.58"
Area (ac) CN Description
31.720 84 Post -Development
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
9.2
150
0.0470
0.27
Sheet Flow, Sheet Flow
Grass: Short n= 0.150 P2= 3.50"
3.3
250
0.0320
1.25
Shallow Concentrated Flow, Shallow flow
Short Grass Pasture Kv= 7.0 fps
1.7
563
0.0320
5.58
44.66 Channel Flow, CHANNEL
Area= 8.0 sf Perim= 16.0' r= 0.50' n= 0.030
14.2
34-
32=
30
w 28-:
26=
0 24-
LL 22
963 Total
Subcatchment 4S: POST WP # 1
Hydrograph
Time (hours)
Charlotte 24-hr 1-yr
1 yr Rainfall=2.58"
Runoff Area=31.720 ac
Runoff Volume=3.115 of
Runoff Depth=1.18"
Flow Length=963'
Tc=14.2 min
CN=84
8� Runoff

Wet Pond # 1 Charlotte 24-hr 1-yr 1 yr Rainfall=2.58"
Prepared by Microsoft Printed 8/27/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 3
Summary for Pond 33P: Wet Pond # 1
Inflow Area = 31.720 ac, Inflow Depth = 1.18" for 1 yr event
Inflow = 45.27 cfs @ 12.12 hrs, Volume= 3.115 of
Outflow = 1.02 cfs @ 19.02 hrs, Volume= 3.111 af, Atten= 98%, Lag= 413.8 min
Primary = 1.02 cfs @ 19.02 hrs, Volume= 3.111 of
Routing by Stor-Ind method, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs / 3
Peak Elev= 663.13' @ 19.02 hrs Surf.Area= 41,392 sf Storage= 95,631 cf
Plug -Flow detention time= 1,252.6 min calculated for 3.110 of (100% of inflow)
Center -of -Mass det. time= 1,252.2 min ( 2,098.8 - 846.6 )
Volume
Invert Avail.Storage
Storage
Description
#1
660.50' 399,250 cf
Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation
Surf.Area Inc.Store
Cum.Store
(feet)
(sq-ft) (cubic -feet)
(cubic -feet)
660.50
29,000
0
0
661.00
34,000
15,750
15,750
662.00
37,000
35,500
51,250
663.00
41,000
39,000
90,250
664.00
44,000
42,500
132,750
665.00
48,000
46,000
178,750
666.00
51,000
49,500
228,250
667.00
55,000
53,000
281,250
668.00
59,000
57,000
338,250
669.00
63,000
61,000
399,250
Device Routinq Invert Outlet Devices
#1
Primary
659.30'
18.0" Round Culvert L= 59.5' Ke= 0.500
Inlet / Outlet Invert= 659.30' / 659.00' S= 0.0050'/' Cc= 0.900
n= 0.012, Flow Area= 1.77 sf
#2
Device 1
660.50'
5.0" Vert. Orifice/Grate C= 0.600
#3
Device 1
663.20'
8.0" Vert. Orifice/Grate C= 0.600
#4
Device 1
667.75'
16.0' long x 0.5' breadth Broad -Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00
Coef. (English) 2.80 2.92 3.08 3.30 3.32
Primary OutFlow Max=1.02 cfs @ 19.02 hrs HW=663.13' (Free Discharge)
t-1=Culvert (Passes 1.02 cfs of 14.76 cfs potential flow)
2=Orifice/Grate (Orifice Controls 1.02 cfs @ 7.49 fps)
3=Orifice/Grate ( Controls 0.00 cfs)
=Broad -Crested Rectangular Weir ( Controls 0.00 cfs)

Wet Pond # 1 Charlotte 24-hr 1-yr 1 yr Rainfall=2.58"
Prepared by Microsoft Printed 8/27/2019
HydroCAD® 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 4
w
3
0
LL
Pond 33P: Wet Pond # 1
Hydrograph
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)
■ Inflow
® Primary

Wet Pond # 1 Charlotte 6-hr 2-yr 2 yr Rainfall=2.28"
Prepared by Microsoft Printed 8/27/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 5
Summary for Subcatchment 4S: POST WP # 1
Runoff = 49.23 cfs @ 3.28 hrs, Volume= 2.506 af, Depth= 0.95"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs
Charlotte 6-hr 2-yr 2 yr Rainfall=2.28"
Area (ac) CN Description
31.720 84 Post -Development
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
9.2
150
0.0470
0.27
Sheet Flow, Sheet Flow
Grass: Short n= 0.150 P2= 3.50"
3.3
250
0.0320
1.25
Shallow Concentrated Flow, Shallow flow
Short Grass Pasture Kv= 7.0 fps
1.7
563
0.0320
5.58
44.66 Channel Flow, CHANNEL
Area= 8.0 sf Perim= 16.0' r= 0.50' n= 0.030
14.2 963 Total
45
40
35
30
�° 25
20
15
10
Subcatchment 4S: POST WP # 1
Hydrograph
Charlotte 6-hr
2-yr
2 yr Rainfall=2.28"
Runoff Area=31.720 ac
Runoff Volume=2.506 of
Runoff Depth=0.95"
Flow Length=963'
Tc=14.2 min
CN=84
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)
Runoff

Wet Pond # 1 Charlotte 6-hr 2-yr 2 yr Rainfall=2.28"
Prepared by Microsoft Printed 8/27/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 6
Summary for Pond 33P: Wet Pond # 1
Inflow Area = 31.720 ac, Inflow Depth = 0.95" for 2 yr event
Inflow = 49.23 cfs @ 3.28 hrs, Volume= 2.506 of
Outflow = 1.04 cfs @ 6.20 hrs, Volume= 2.503 af, Atten= 98%, Lag= 175.2 min
Primary = 1.04 cfs @ 6.20 hrs, Volume= 2.503 of
Routing by Stor-Ind method, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs / 3
Peak Elev= 663.20' @ 6.20 hrs Surf.Area= 41,601 sf Storage= 98,522 cf
Plug -Flow detention time= 1,193.0 min calculated for 2.503 of (100% of inflow)
Center -of -Mass det. time= 1,192.8 min ( 1,419.3 - 226.5 )
Volume Invert Avail.Storage Storage Description
#1 660.50' 399,250 cf Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic -feet) (cubic -feet)
660.50 29,000 0 0
661.00 34,000 15,750 15,750
662.00 37,000 35,500 51,250
663.00 41,000 39,000 90,250
664.00 44,000 42,500 132,750
665.00 48,000 46,000 178,750
666.00 51,000 49,500 228,250
667.00 55,000 53,000 281,250
668.00 59,000 57,000 338,250
669.00 63,000 61,000 399,250
Device Routing Invert Outlet Devices
#1 Primary 659.30' 18.0" Round Culvert L= 59.5' Ke= 0.500
Inlet / Outlet Invert= 659.30' / 659.00' S= 0.0050 T Cc= 0.900
n= 0.012, Flow Area= 1.77 sf
#2 Device 1 660.50' 5.0" Vert. Orifice/Grate C= 0.600
#3 Device 1 663.20' 8.0" Vert. Orifice/Grate C= 0.600
#4 Device 1 667.75' 16.0' long x 0.5' breadth Broad -Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00
Coef. (English) 2.80 2.92 3.08 3.30 3.32
Primary OutFlow Max=1.04 cfs @ 6.20 hrs HW=663.20' (Free Discharge)
L1=Culvert (Passes 1.04 cfs of 14.96 cfs potential flow)
2=Orifice/Grate (Orifice Controls 1.04 cfs @ 7.60 fps)
3=Orifice/Grate (Orifice Controls 0.00 cfs @ 0.06 fps)
=Broad -Crested Rectangular Weir ( Controls 0.00 cfs)

Wet Pond # 1 Charlotte 6-hr 2-yr 2 yr Rainfall=2.28"
Prepared by Microsoft Printed 8/27/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 7
Pond 33P: Wet Pond # 1
Hydrograph
■ Inflow
® Primary
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)

Wet Pond # 1 Charlotte 6-hr 10-yr 10 yr Rainfall=3.72"
Prepared by Microsoft Printed 8/27/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 8
Summary for Subcatchment 4S: POST WP # 1
Runoff = 103.44 cfs @ 3.27 hrs, Volume= 5.620 af, Depth= 2.13"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs
Charlotte 6-hr 10-yr 10 yr Rainfall=3.72"
Area (ac) CN Description
31.720 84 Post -Development
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
9.2
150
0.0470
0.27
Sheet Flow, Sheet Flow
Grass: Short n= 0.150 P2= 3.50"
3.3
250
0.0320
1.25
Shallow Concentrated Flow, Shallow flow
Short Grass Pasture Kv= 7.0 fps
1.7
563
0.0320
5.58
44.66 Channel Flow, CHANNEL
Area= 8.0 sf Perim= 16.0' r= 0.50' n= 0.030
14.2
115
11�10
100
963 Total
Subcatchment 4S: POST WP # 1
Hydrograph
Runoff
90
85
80
75
70
H 65
60
0 55
LL 50
45
40'
Charlotte 6-hr 10-yr
10 yr Rainfall=3.72"
Runoff Area=31.720 ac
Runoff Volume=5.620 of
Runoff Depth=2.13"
Flow Length=963'
Tc=14.2 min
CN=84
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)

Wet Pond # 1 Charlotte 6-hr 10-yr 10 yr Rainfall=3.72"
Prepared by Microsoft Printed 8/27/2019
HydroCAD® 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 9
Summary for Pond 33P: Wet Pond # 1
Inflow Area = 31.720 ac, Inflow Depth = 2.13" for 10 yr event
Inflow = 103.44 cfs @ 3.27 hrs, Volume= 5.620 of
Outflow = 3.85 cfs @ 6.05 hrs, Volume= 5.616 af, Atten= 96%, Lag= 166.8 min
Primary = 3.85 cfs @ 6.05 hrs, Volume= 5.616 of
Routing by Stor-Ind method, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs / 3
Peak Elev= 665.58' @ 6.05 hrs Surf.Area= 49,726 sf Storage= 206,862 cf
Plug -Flow detention time= 1,047.5 min calculated for 5.616 of (100% of inflow)
Center -of -Mass det. time= 1,047.9 min ( 1,268.2 - 220.3 )
Volume Invert Avail.Storage Storage Description
#1 660.50' 399,250 cf Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic -feet) (cubic -feet)
660.50 29,000 0 0
661.00 34,000 15,750 15,750
662.00 37,000 35,500 51,250
663.00 41,000 39,000 90,250
664.00 44,000 42,500 132,750
665.00 48,000 46,000 178,750
666.00 51,000 49,500 228,250
667.00 55,000 53,000 281,250
668.00 59,000 57,000 338,250
669.00 63,000 61,000 399,250
Device Routing Invert Outlet Devices
#1 Primary 659.30' 18.0" Round Culvert L= 59.5' Ke= 0.500
Inlet / Outlet Invert= 659.30' / 659.00' S= 0.0050'/' Cc= 0.900
n= 0.012, Flow Area= 1.77 sf
#2 Device 1 660.50' 5.0" Vert. Orifice/Grate C= 0.600
#3 Device 1 663.20' 8.0" Vert. Orifice/Grate C= 0.600
#4 Device 1 667.75' 16.0' long x 0.5' breadth Broad -Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00
Coef. (English) 2.80 2.92 3.08 3.30 3.32
Primary OutFlow Max=3.85 cfs @ 6.05 hrs HW=665.58' (Free Discharge)
L1=Culvert (Passes 3.85 cfs of 20.00 cfs potential flow)
2=Orifice/Grate (Orifice Controls 1.45 cfs @ 10.62 fps)
3=Orifice/Grate (Orifice Controls 2.40 cfs @ 6.88 fps)
=Broad -Crested Rectangular Weir ( Controls 0.00 cfs)

Wet Pond # 1 Charlotte 6-hr 10-yr 10 yr Rainfall=3.72"
Prepared by Microsoft Printed 8/27/2019
HydroCAD® 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 10
w
3
0
LL
Pond 33P: Wet Pond # 1
Hydrograph
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)
■ -inflow
® Primary

Wet Pond # 1 Charlotte 6-hr 25-yr 25 yr Rainfall=4.38"
Prepared by Microsoft Printed 8/27/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 11
Summary for Subcatchment 4S: POST WP # 1
Runoff = 130.28 cfs @ 3.23 hrs, Volume= 7.160 af, Depth= 2.71"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs
Charlotte 6-hr 25-yr 25 yr Rainfall=4.38"
Area (ac) CN Description
31.720 84 Post -Development
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
9.2
150
0.0470
0.27
Sheet Flow, Sheet Flow
Grass: Short n= 0.150 P2= 3.50"
3.3
250
0.0320
1.25
Shallow Concentrated Flow, Shallow flow
Short Grass Pasture Kv= 7.0 fps
1.7
563
0.0320
5.58
44.66 Channel Flow, CHANNEL
Area= 8.0 sf Perim= 16.0' r= 0.50' n= 0.030
14.2 963 Total
Subcatchment 4S: POST WP # 1
Hydrograph
140-130.28 cs
130
Charlotte 6-hr
120 110 25-+ r
100 25,yr Rainfa11=4.38"
90 Runoff Area'=31.720 ac
8 Runoff !Volume=7.160 of
°
FL 60
70 Runoff Depth=2.71"
50 Flow Length=963'
40 Tc=14.2 min
3° CN=84
20
10
°-
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)
Runoff

Wet Pond # 1 Charlotte 6-hr 25-yr 25 yr Rainfall=4.38"
Prepared by Microsoft Printed 8/27/2019
HydroCAD® 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 12
Summary for Pond 33P: Wet Pond # 1
Inflow Area = 31.720 ac, Inflow Depth = 2.71" for 25 yr event
Inflow
= 130.28 cfs @
3.23 hrs, Volume= 7.160 of
Outflow
= 4.60 cfs @
6.05 hrs, Volume= 7.156 af, Atten= 96%, Lag= 169.4 min
Primary
= 4.60 cfs @
6.05 hrs, Volume= 7.156 of
Routing by Stor-Ind method, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs / 3
Peak Elev=
666.70' @ 6.05 hrs
Surf.Area= 53,818 sf Storage= 265,174 cf
Plug -Flow
detention time= 1,027.2
min calculated for 7.156 of (100% of inflow)
Center -of -Mass
det. time= 1,027.1
min ( 1,243.7 - 216.5 )
Volume
Invert Avail.Storage Storage Description
#1
660.50' 399,250 cf Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation
Surf.Area
Inc.Store Cum.Store
(feet)
(sq-ft)
(cubic -feet) (cubic -feet)
660.50
29,000
0 0
661.00
34,000
15,750 15,750
662.00
37,000
35,500 51,250
663.00
41,000
39,000 90,250
664.00
44,000
42,500 132,750
665.00
48,000
46,000 178,750
666.00
51,000
49,500 228,250
667.00
55,000
53,000 281,250
668.00
59,000
57,000 338,250
669.00
63,000
61,000 399,250
Device Routinq Invert
Outlet Devices
#1
Primary
659.30'
18.0" Round Culvert L= 59.5' Ke= 0.500
Inlet / Outlet Invert= 659.30' / 659.00' S= 0.0050'/' Cc= 0.900
n= 0.012, Flow Area= 1.77 sf
#2
Device 1
660.50'
5.0" Vert. Orifice/Grate C= 0.600
#3
Device 1
663.20'
8.0" Vert. Orifice/Grate C= 0.600
#4
Device 1
667.75'
16.0' long x 0.5' breadth Broad -Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00
Coef. (English) 2.80 2.92 3.08 3.30 3.32
Primary OutFlow Max=4.60 cfs @ 6.05 hrs HW=666.70' (Free Discharge)
t-1=Culvert (Passes 4.60 cfs of 21.95 cfs potential flow)
2=Orifice/Grate (Orifice Controls 1.61 cfs @ 11.79 fps)
3=Orifice/Grate (Orifice Controls 2.99 cfs @ 8.57 fps)
=Broad -Crested Rectangular Weir ( Controls 0.00 cfs)

Wet Pond # 1 Charlotte 6-hr 25-yr 25 yr Rainfall=4.38"
Prepared by Microsoft Printed 8/27/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 13
N
U
O
LL
Pond 33P: Wet Pond # 1
Hydrograph
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)
■ Inflow
p Primary

Wet Pond # 1 Charlotte 6-hr 50-yr 50 yr Rainfall=4.92"
Prepared by Microsoft Printed 8/27/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 14
Summary for Subcatchment 4S: POST WP # 1
Runoff = 150.50 cfs @ 3.23 hrs, Volume= 8.452 af, Depth= 3.20"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs
Charlotte 6-hr 50-yr 50 yr Rainfall=4.92"
Area (ac) CN Description
31.720 84 Post -Development
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
9.2
150
0.0470
0.27
Sheet Flow, Sheet Flow
Grass: Short n= 0.150 P2= 3.50"
3.3
250
0.0320
1.25
Shallow Concentrated Flow, Shallow flow
Short Grass Pasture Kv= 7.0 fps
1.7
563
0.0320
5.58
44.66 Channel Flow, CHANNEL
Area= 8.0 sf Perim= 16.0' r= 0.50' n= 0.030
14.2
16[
15C
14C
130
120
110
100
H
90
a 80
`L 70
60
50
1
963 Total
Subcatchment 4S: POST WP # 1
Hydrograph
Charlotte 6-hr
50-yr
50 yr Rainfall=4.92"
Runoff Area=31.720 ac
Runoff Volume=8.452 of
Runoff Depth=3.20"
Flow Length=963'
Tc=14.2 min
CN=84
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)
Runoff

Wet Pond # 1 Charlotte 6-hr 50-yr 50 yr Rainfall=4.92"
Prepared by Microsoft Printed 8/27/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 15
Summary for Pond 33P: Wet Pond # 1
Inflow Area = 31.720 ac, Inflow Depth = 3.20" for 50 yr event
Inflow = 150.50 cfs @ 3.23 hrs, Volume= 8.452 of
Outflow = 5.12 cfs @ 6.07 hrs, Volume= 8.447 af, Atten= 97%, Lag= 170.4 min
Primary = 5.12 cfs @ 6.07 hrs, Volume= 8.447 of
Routing by Stor-Ind method, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs / 3
Peak Elev= 667.61' @ 6.07 hrs Surf.Area= 57,427 sf Storage= 315,358 cf
Plug -Flow detention time= 1,028.0 min calculated for 8.446 of (100% of inflow)
Center -of -Mass det. time= 1,028.4 min ( 1,244.1 - 215.7 )
Volume
Invert Avail.Storage Storage
Description
#1
660.50' 399,250
cf Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation
Surf.Area
Inc.Store
Cum.Store
(feet)
(sq-ft)
(cubic -feet)
(cubic -feet)
660.50
29,000
0
0
661.00
34,000
15,750
15,750
662.00
37,000
35,500
51,250
663.00
41,000
39,000
90,250
664.00
44,000
42,500
132,750
665.00
48,000
46,000
178,750
666.00
51,000
49,500
228,250
667.00
55,000
53,000
281,250
668.00
59,000
57,000
338,250
669.00
63,000
61,000
399,250
Device Routinq Invert Outlet Devices
#1
Primary
659.30'
18.0" Round Culvert L= 59.5' Ke= 0.500
Inlet / Outlet Invert= 659.30' / 659.00' S= 0.0050 '/' Cc= 0.900
n= 0.012, Flow Area= 1.77 sf
#2
Device 1
660.50'
5.0" Vert. Orifice/Grate C= 0.600
#3
Device 1
663.20'
8.0" Vert. Orifice/Grate C= 0.600
#4
Device 1
667.75'
16.0' long x 0.5' breadth Broad -Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00
Coef. (English) 2.80 2.92 3.08 3.30 3.32
Primary OutFlow Max=5.12 cfs @ 6.07 hrs HW=667.61' (Free Discharge)
L1=Culvert (Passes 5.12 cfs of 23.39 cfs potential flow)
2=Orifice/Grate (Orifice Controls 1.72 cfs @ 12.65 fps)
3=Orifice/Grate (Orifice Controls 3.39 cfs @ 9.72 fps)
=Broad -Crested Rectangular Weir ( Controls 0.00 cfs)

Wet Pond # 1 Charlotte 6-hr 50-yr 50 yr Rainfall=4.92"
Prepared by Microsoft Printed 8/27/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 16
Pond 33P: Wet Pond # 1
Hydrograph
■ Inflow
■ Primary
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)

Wet Pond # 1 Charlotte 6-hr 100-yr 100 yr Rainfall=5.34"
Prepared by Microsoft Printed 8/27/2019
HydroCAD® 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 17
Summary for Subcatchment 4S: POST WP # 1
Runoff = 170.20 cfs @ 3.23 hrs, Volume= 9.471 af, Depth= 3.58"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs
Charlotte 6-hr 100-yr 100 yr Rainfall=5.34"
Area (ac) CN Description
31.720 84 Post -Development
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
9.2
150
0.0470
0.27
Sheet Flow, Sheet Flow
Grass: Short n= 0.150 P2= 3.50"
3.3
250
0.0320
1.25
Shallow Concentrated Flow, Shallow flow
Short Grass Pasture Kv= 7.0 fps
1.7
563
0.0320
5.58
44.66 Channel Flow, CHANNEL
Area= 8.0 sf Perim= 16.0' r= 0.50' n= 0.030
14.2
170
160
150-
140
130
120
H 110'
100
p 90-
LL 80
70
963 Total
Subcatchment 4S: POST WP # 1
1
10
20
30
40
50
.0 70
Hydrograph
Charlotte 6-hr
100-yr
100 yr Rainfall=5.34"
Runoff Area=31.720 ac
Runoff Volume=9.471 of
Runoff Depth=3.58"
Flow Length=963'
Tc=1'4.2 min
CN=84
80 90 100 110 120 130 140 150 160 170
Time (hours)
® Runoff

Wet Pond # 1 Charlotte 6-hr 100-yr 100 yr Rainfall=5.34"
Prepared by Microsoft Printed 8/27/2019
HydroCAD® 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 18
Summary for Pond 33P: Wet Pond # 1
Inflow Area = 31.720 ac, Inflow Depth = 3.58" for 100 yr event
Inflow = 170.20 cfs @ 3.23 hrs, Volume= 9.471 of
Outflow = 10.12 cfs @ 4.78 hrs, Volume= 9.466 af, Atten= 94%, Lag= 93.5 min
Primary = 10.12 cfs @ 4.78 hrs, Volume= 9.466 of
Routing by Stor-Ind method, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs / 3
Peak Elev= 667.97' @ 4.78 hrs Surf.Area= 58,897 sf Storage= 336,734 cf
Plug -Flow detention time= 966.6 min calculated for 9.465 of (100% of inflow)
Center -of -Mass det. time= 967.1 min ( 1,181.8 - 214.8 )
Volume Invert Avail.Storage Storage Description
#1 660.50' 399,250 cf Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic -feet) (cubic -feet)
660.50 29,000 0 0
661.00 34,000 15,750 15,750
662.00 37,000 35,500 51,250
663.00 41,000 39,000 90,250
664.00 44,000 42,500 132,750
665.00 48,000 46,000 178,750
666.00 51,000 49,500 228,250
667.00 55,000 53,000 281,250
668.00 59,000 57,000 338,250
669.00 63,000 61,000 399,250
Device Routing Invert Outlet Devices
#1 Primary 659.30' 18.0" Round Culvert L= 59.5' Ke= 0.500
Inlet / Outlet Invert= 659.30' / 659.00' S= 0.0050'/' Cc= 0.900
n= 0.012, Flow Area= 1.77 sf
#2 Device 1 660.50' 5.0" Vert. Orifice/Grate C= 0.600
#3 Device 1 663.20' 8.0" Vert. Orifice/Grate C= 0.600
#4 Device 1 667.75' 16.0' long x 0.5' breadth Broad -Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00
Coef. (English) 2.80 2.92 3.08 3.30 3.32
Primary OutFlow Max=10.09 cfs @ 4.78 hrs HW=667.97' (Free Discharge)
L1=Culvert (Passes 10.09 cfs of 23.95 cfs potential flow)
2=Orifice/Grate (Orifice Controls 1.77 cfs @ 12.98 fps)
3=Orifice/Grate (Orifice Controls 3.54 cfs @ 10.15 fps)
=Broad -Crested Rectangular Weir (Weir Controls 4.78 cfs @ 1.33 fps)

Wet Pond # 1 Charlotte 6-hr 100-yr 100 yr Rainfall=5.34"
Prepared by Microsoft Printed 8/27/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 19
1
1
1
1
1
N 1
1
3
0
LL
Pond 33P: Wet Pond # 1
Hydrograph
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)
■ Inflow
■ Primary

WET POND #2
CALCULATIONS

YARBROUGH-WILLIAMS & HOULE, INC.
Planning • Surveying • Engineering
Wet Pond Calculations P. O .BOX 7007
References: NCDENR DWQ BMP Design Manual CHARLOTTE, N.C. 28241
Phone: [phone]
Date : April 26,2019 Fax: [phone]
PROJECT: Courtyards on Lawyers Road
Base Data
Site Area Post = Total Drainage Area (Ac) = 14.34 ac
Pre-dev. Drainage Area ( Ac) 14.34 ac
Post Dev. Impervious Area (Ac) = 8.44
Measured Impervious Area - 59
Soils Types: Cecil, Enon,
Zoning: Residential
Hydrologic Data
Pre - CN
Land Use
Soil Type
H drolo is Grou
CN
(weighted) CN
0.27
Woods/GRASS
B
58
1.09
6.91
Woods/GRASS
C
72
34.69
7.16
Woods/GRASS
D
79
39.44
14.34
Pre
CNpa,,
75
Post - CN
Acreage
Land Use
Soil Type
Hydrologic Groug
CN1(weighted)
CN
8.4
Bld / vt
98
57.68
0.1
Grass
B
61
0.47
2.8
Grass
C
74
14.66
3.0
Grass
D
80
16.46
14.34
Post CNpo,i 89
CN 89

Steps 1 Determine if the development site and conditions are appropriate for the use of a
Wet Pond and consider any site -specific design considerations.
Step 2 Compute Water Quality Volume (WQv)
( WQv for the Goose Creek Watershed shall be the difference in the storm water runoff from the pre -development and post -development conditions
Step 3
for the 1-year, 24 hour storm.
Pre -development 1-year, 24 hr storm volume =
Post -development 1-year, 24 hr stone volume =
DIFFERENCE IN 1 YEAR STORM VOLUME _
AT ELEV. 665.03 THE VOLUME TREATED IS =
Compute Site Hydrologic Input Parameters
Using SCS hydrologic procedures and/or computer models the following data can
be determined for the development site.
HYDROLOGIC INPUT DATA
36,329
79366.32
43,037 of required for treatment
44,997 cf RELEASED GRADUALLY DURING 120 HOURS
WITH A PEAK RATE OF Approx. 0.37 offs
Condition
Area
CN
k (hours)
4 (min)
Pre dev
14.34
ac
75
0.51
30.5
Post dev
14.34
ac
89
0.39
23.4

Results of Preliminary Hydrologic Calculations
(From Computer Model Results Using SCS Hydrologic Procedures)
Condition Runoff
Q",,
Q2.y,,,
Q10 _
Q25,_
Q50 y,,,
cis
cfs
cfs
cfs
cis
Pre -development Flow
7.45
7.48
21.90
29.47
35.54
Post Development Detained
1.91
2.54
9.74
11.98
21.03
The facility would require 0.99 ac-ft for
Water Quality Volume (WQv) treatment
Perm Pool Storage -Elevation Data
Elevation
Area (sf)
Area (so)
Ht (ft)
Inc. Vol Jac-ft)
Acc. Vol (ac-ft)
Acc. Vol (cf)
649
900
0.021
0.0
0.000
0.000
0
650
1200.0
0.028
1.0
0.024
0.024
1050
652
1800.0
0.041
3.0
0.069
0.093
4050
654
2600.0
0.060
5.0
0.101
0.194
8450
656
3400.0
1 0.078
7.0
0.138
0.332
14450
656
4400.0
0.101
9.0
0.179
0.511
22250
660
5500.0
0.126
11.0
0.227
1 0.738
32150
662
6700.0
0.154
13.0
0.280
1.018
44350
662.5
7600.0
0.114
12.5
0.082
1.100
47925
Permanent Pool Volume
Depth =
13.50
ft
PPE Elevation =
662.5
Shelf Elevation =
662
Bottom Elevation =
648
Bottom Elevation +1 =
649
PPE Surface Area =
7,600
sf
Shelf Area = 1
6,7001
sf
Surface Area Bot Pond =
900
sf
Permanent Pool Volume =
47,925 1
of
Vshelf
252 cf
Avg. Depth = 7.12 ft
Using avg = 7.12 and 59% impervious cover, Min. SA/DA Ratio
Surface area required = 6806 sf
Surface area provided = 7600 sf
Step 4 Size Flow Diversion Structure - No Diversion Structure
Step 5 Compute Release Rates for Water Quality Control
Compute the release rate for water quality control.
The water quality control volume (WQv) is to be released over a 2-day
duration beyond the center of rainfall (48 hours plus 3 hours) period.
Release Rate = - 0.99 ac-ft X 43560 ft2/acre / (51 hrs X 3600 secthr)
0.234 cfs

Step 6
Compute Forebay Chamber Volume
The forebay chamber storage area above the filter media must be sized to hold 20
percent of the water quality volume
Required Forebay Chamber Volume = 47925.00 of x (0.15) _
7188.75 cf = 0.17 ac-ft
Proposed Forebay Chamber Volume = 7350 cf
Forebay Chamber Stora e-Elevation
Data
Elevation
Area sf
Area ac
Ht ft
Inc. Vol ac-ft
Acc. Vol ac-ft
Acc. Vol c
656
300.0
0.007
0.0
0.000
0.000
0.0
658
700.0
0.016
2.0
0.023
0.023
1000.0
659
1000.0
0.023
3.0
0.020
0.042
1850.0
660
1300.0
0.030
4.0
0.026
0.069
3000.0
661
1600.0
0.037
5.0
0.033
0.102
4450.0
662
2000.0
0.046
6.0
0.041
0.143
6250.0
6'.5
2400.0
0.055
6.5
0.025
0.169
7350.0
Step 7 Develop Water Quality Storage -Elevation Table
Permanent Pond Surface Elev. = 1 662.5
Water Quality Storage -Elevation Data
Elevation
Areas
Area ac
Ht ft
Inc. Vol ac-ft
Acc. Vol ac-ft
Acc. Vol c
662.5
10000.0
0.230
0.0
0.000
0.0
663
11300.0
0.259
0.5
0.122
0.122
5325.0
665
14000.0
0.321
2.5
0.581
0.703
30625.0
667
17100.0
0.393
4.5
0.714
1.417
61725.0
669
20300.0
0.466
6.5
0.859
2.276
99125.0
671
23900.0
0.549
8.5
1.015
3.290
143325.0
Step 8 Route Runoff Hydrographs through Wet Pond
Route all of the appropriate runoff hydrographs through the wet pond facility with the following goals:
Release water quality volume (WQV) within 48-120 hours
Step 9 Water Quality Release Orifice Sizing
A=
12000.0
sf - avg.
hi
2.50
C=
0.6
9=
32.2
t =
172800 sec = 48 hrs
a =
0.04561
Die =
3 in

Step 10 Calculation for Anti -flotation Concrete Anchor
A. Bouyancy
Elevation
sf
sf Tx 7'
Top of Dam =
671.00
Top of Box =
669.35
Pond Shelf =
662.00
Bottom of Box =
660.91
Box Area =
25
Anchor Area =
49
Anchor thickness =
1
Area of Riser - Inside 16 sf / Outside 25 sf
V (wetwell) = V (riser) + V(base footing) _ (669.35 - 660.91) X 25 + (1.0 X 49) = 260 cf
Floatation = V(wetwell) x V(water) = 260 cf x 62.4 lb/cf = 16224 Ibs
B. Counter Bouyancy
Cone. Wt. _ {V(conc. riser) + V(conc. Footing)) x Cone. Unit Wt. _
{(25-16) x (669.35-660.91)+ (49 x 1)) x 150 Ibs/cf = 18744 Ibs
Earth Wt. = V(Earth) X Earth Unit Wt. _
(49-25) X 1.59 X 115 LBS/CF = 4388 Ibs
Anti -Floatation = 23132 Ibs
C. Safety Factor= 1.4 1.1 required by NCDENR for Anti-floation
xTx

WET POND #2
HYDROCAD REPORT

PRE DRAINAGE AREA
Su4
Reach Pon L
ink

Wet Pond #2 071219 Charlotte 24-hr 1-yr 1 yr Rainfall=2.58"
Prepared by Microsoft Printed 8/27/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 2
Summary for Subcatchment 1S: PRE DRAINAGE AREA
Runoff = 7.45 cfs @ 12.34 hrs, Volume= 0.834 af, Depth= 0.70"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs
Charlotte 24-hr 1-yr 1 yr Rainfall=2.58"
Area (ac) CN Description
0.270 58 GROUP B
6.910 72 GROUP C
7.160 79 GROUP D
14.340 75 Weighted Average
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
23.2
150
0.0330
0.11
Sheet Flow, SHEET FLOW
Woods: Light underbrush n= 0.400 P2= 3.50"
4.8
250
0.0300
0.87
Shallow Concentrated Flow, SHALLOW CONCENTRATED
Woodland Kv= 5.0 fps
2.5
775
0.0280
5.22
41.77 Channel Flow, CHANNEL
Area= 8.0 sf Perim= 16.0' r= 0.50' n= 0.030
30.5 1,175 Total
Subcatchment 1S: PRE DRAINAGE AREA
Hydrograph
0 Runoff
Charlotte 24-hr 1-yr
7-
1 yr Rai'nfa,11=2.58"
6- Runoff Area=14.340 ac
5 l ' 1 0 Runoff 'Volume=0.834 of
Runoff Depth=0.70"
4 11
Flow Lenqth=1175'
31 I E Tc=30.5 min
CN=75
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)

Wet Pond #2 071219 Charlotte 6-hr 2-yr 2 yr Rainfall=2.28"
Prepared by Microsoft Printed 8/27/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 3
Summary for Subcatchment 1S: PRE DRAINAGE AREA
Runoff = 7.48 cfs @ 3.56 hrs, Volume= 0.629 af, Depth= 0.53"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs
Charlotte 6-hr 2-yr 2 yr Rainfall=2.28"
Area (ac) CN Description
0.270 58 GROUP B
6.910 72 GROUP C
7.160 79 GROUP D
14.340 75 Weighted Average
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
23.2
150
0.0330
0.11
Sheet Flow, SHEET FLOW
Woods: Light underbrush n= 0.400 P2= 3.50"
4.8
250
0.0300
0.87
Shallow Concentrated Flow, SHALLOW CONCENTRATED
Woodland Kv= 5.0 fps
2.5
775
0.0280
5.22
41.77 Channel Flow, CHANNEL
Area= 8.0 sf Perim= 16.0' r= 0.50' n= 0.030
30.5 1,175 Total
Subcatchment 1S: PRE DRAINAGE AREA
Hydrograph
� Runoff
Charlotte6-hr
7
2-yr
6.: 2,yr Rai',nfall=2.28"
5- Runoff Area=14.340 ac
Runoff Volume=0.629 of
4- Runoff Depth=0.53"
LL
3 Flow Length=1175'
2= Tc=30.5 m i n
CN=75
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)

Wet Pond #2 071219 Charlotte 6-hr 10-yr 10 yr Rainfall=3.72"
Prepared by Microsoft Printed 8/27/2019
HydroCAD@) 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 4
Summary for Subcatchment 1S: PRE DRAINAGE AREA
Runoff = 21.90 cfs @ 3.52 hrs, Volume= 1.744 af, Depth= 1.46"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs
Charlotte 6-hr 10-yr 10 yr Rainfall=3.72"
Area (ac) CN Description
0.270 58 GROUP B
6.910 72 GROUP C
7.160 79 GROUP D
14.340 75 Weighted Average
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
23.2
150
0.0330
0.11
Sheet Flow, SHEET FLOW
Woods: Light underbrush n= 0.400 P2= 3.50"
4.8
250
0.0300
0.87
Shallow Concentrated Flow, SHALLOW CONCENTRATED
Woodland Kv= 5.0 fps
2.5
775
0.0280
5.22
41.77 Channel Flow, CHANNEL
Area= 8.0 sf Perim= 16.0' r= 0.50' n= 0.030
30.5 1,175 Total
Subcatchment 1S: PRE DRAINAGE AREA
Hydrograph
® Runoff
22 21Charlotte 6-hr 10-yr
-
9 10 yr Rainfall=3.7211
18 Runoff Area=14.340 ac
1
15- Runoff Volume=1.744 of
14
13 Runoff Depth=1.4611
3 12
LL 11- Flow Length=1175'
91 Tc=30.5 m i n
8_
CN=75
1 -
0 10 20 30 40 50 .1 1 :1 •1 11 1 0 120 130 140 150 160 170

Wet Pond #2 071219 Charlotte 6-hr 25-yr 25 yr Rainfall=4.38"
Prepared by Microsoft Printed 8/27/2019
HydroCAD® 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 5
Summary for Subcatchment 1S: PRE DRAINAGE AREA
Runoff = 29.47 cfs @ 3.46 hrs, Volume= 2.338 af, Depth= 1.96"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs
Charlotte 6-hr 25-yr 25 yr Rainfall=4.38"
Area (ac) CN Description
0.270 58 GROUP B
6.910 72 GROUP C
7.160 79 GROUP D
14.340 75 Weighted Average
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
23.2
150
0.0330
0.11
Sheet Flow, SHEET FLOW
Woods: Light underbrush n= 0.400 P2= 3.50"
4.8
250
0.0300
0.87
Shallow Concentrated Flow, SHALLOW CONCENTRATED
Woodland Kv= 5.0 fps
2.5
775
0.0280
5.22
41.77 Channel Flow, CHANNEL
Area= 8.0 sf Perim= 16.0' r= 0.50' n= 0.030
30.5 1,175 Total
Subcatchment 1S: PRE DRAINAGE AREA
Hydrograph
Runoff
28__ Charlotte 6-hr
26 25-yr
24_ " 25 yr Rainfall=4.38"
22.=
20 Runoff Area=14.340 ac
'$ Runoff Volume=2.338 of
1q._ "
Runoff Depth=1.96"
12 Flow Length=1175'
10 Tc=30.5 m i n
8..
6_ CN=75
Time (hours)

Wet Pond #2 071219 Charlotte 6-hr 50-yr 50 yr Rainfall=4.92"
Prepared by Microsoft Printed 8/27/2019
HydroCAD0 10.00-22 s/n 05047 ©2018 HydroCAD Software Solutions LLC Page 6
Summary for Subcatchment 1S: PRE DRAINAGE AREA
Runoff = 35.54 cfs @ 3.46 hrs, Volume= 2.850 af, Depth= 2.38"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs
Charlotte 6-hr 50-yr 50 yr Rainfall=4.92"
Area (ac) CN Description
0.270 58 GROUP B
6.910 72 GROUP C
7.160 79 GROUP D
14.340 75 Weighted Average
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
23.2
150
0.0330
0.11
Sheet Flow, SHEET FLOW
Woods: Light underbrush n= 0.400 P2= 3.50"
4.8
250
0.0300
0.87
Shallow Concentrated Flow, SHALLOW CONCENTRATED
Woodland Kv= 5.0 fps
2.5
775
0.0280
5.22
41.77 Channel Flow, CHANNEL
Area= 8.0 sf Perim= 16.0' r= 0.50' n= 0.030
30.5
34
32
30
28
92
3 2
0 1
E
12
10
8
6
4
1,175 Total
Subcatchment 1S: PRE DRAINAGE AREA
Hydrograph
Charlotte 6-hr
50-yr
50 yr Rainfall=4.92"
Runoff Area=14.340 ac
Runoff Volume=2.850 of
Runoff Depth=2.38"
Flow Length=1175'
Tc=30.5 m i n
CN=75
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)
Runoff

Wet Pond #2 071219 Charlotte 6-hr 100-yr 100 yr Rainfall=5.34"
Prepared by Microsoft Printed 8/27/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 7
Summary for Subcatchment 1S: PRE DRAINAGE AREA
Runoff = 41.14 cfs @ 3.46 hrs, Volume= 3.260 af, Depth= 2.73"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs
Charlotte 6-hr 100-yr 100 yr Rainfall=5.34"
Area (ac) CN Description
0.270 58 GROUP B
6.910 72 GROUP C
7.160 79 GROUP D
14.340 75 Weighted Average
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
23.2
150
0.0330
0.11
Sheet Flow, SHEET FLOW
Woods: Light underbrush n= 0.400 P2= 3.50"
4.8
250
0.0300
0.87
Shallow Concentrated Flow, SHALLOW CONCENTRATED
Woodland Kv= 5.0 fps
2.5
775
0.0280
5.22
41.77 Channel Flow, CHANNEL
Area= 8.0 sf Perim= 16.0' r= 0.50' n= 0.030
30.5 1,175 Total
Subcatchment 1 S: PRE DRAINAGE AREA
Hydrograph
® Runoff
40=
Charlotte 6-hr
38-
36
/�
1 VO-yr
34
-
32-
100 yr Rainfall=5.34"
30 28_
Runoff Area=14.340 ac
w 26
24
Runoff Volume=3.260 of
° 22:
LL 20-.
cRunoff Depth=2.73"
16=
Flow Length=1175'
14 _
12
Tc=30.5 m i n
10 _
CN=75
6=
4=
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)

4s > vN
POST WP #2
Subcat Reach on Link
Wet Pond # 2

Wet Pond #2 071219 Charlotte 24-hr 1-yr 1 yr Rainfall=2.58"
Prepared by Microsoft Printed 8/27/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 2
Summary for Subcatchment 4S: POST WP #2
Runoff = 21.26 cfs @ 12.22 hrs, Volume= 1.822 af, Depth= 1.52"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs
Charlotte 24-hr 1-yr 1 yr Rainfall=2.58"
Area (ac) CN Description
14.340 89 Post -Development
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
18.3
150
0.0600
0.14
Sheet Flow, SHEET
Woods: Light underbrush n= 0.400 P2= 3.50"
5.0
250
0.0280
0.84
Shallow Concentrated Flow, SHALLOW CONCENTRATED
Woodland Kv= 5.0 fps
0.1
30
0.0830
8.99
71.92 Channel Flow, CHANNEL
Area= 8.0 sf Perim= 16.0' r= 0.50' n= 0.030
23.4 430 Total
21
fl
17
16
15
14
13
12
0 11
1 10
8
7
1-
0
0
Subcatchment 4S: POST WP #2
Hydrograph
Charlotte 24-hr 1-yr
1 yr Rainfall=2.58"
Runoff Area=14.340 ac
Runoff :Vol ume=1.822 of
Runoff Depth=1.52"
Flow Length=430'
Tc=23.4 m i n
CN=89
10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)
Runoff

Wet Pond #2 071219 Charlotte 24-hr 1-yr 1 yr Rainfall=2.58"
Prepared by Microsoft Printed 8/27/2019
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Summary for Pond 33P: Wet Pond # 2
Inflow Area = 14.340 ac, Inflow Depth = 1.52" for 1 yr event
Inflow = 21.26 cfs @ 12.22 hrs, Volume= 1.822 of
Outflow = 1.91 cfs @ 13.44 hrs, Volume= 1.822 af, Atten= 91 %, Lag= 73.2 min
Primary = 1.91 cfs @ 13.44 hrs, Volume= 1.822 of
Routing by Stor-Ind method, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs / 3
Peak Elev= 666.10' @ 13.44 hrs Surf.Area= 15,662 sf Storage= 47,003 cf
Plug -Flow detention time= 930.9 min calculated for 1.822 of (100% of inflow)
Center -of -Mass det. time= 931.3 min ( 1,766.7 - 835.5 )
Volume Invert Avail.Storage Storage Description
#1 662.50' 143,325 cf Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic -feet) (cubic -feet)
662.50 10,000 0 0
663.00 11,300 5,325 5,325
664.00 12,700 12,000 17,325
665.00 14,000 13,350 30,675
666.00 15,500 14,750 45,425
667.00 17,100 16,300 61,725
668.00 18,700 17,900 79,625
669.00 20,300 19,500 99,125
670.00 22,100 21,200 120,325
671.00 23,900 23,000 143,325
Device Routinq Invert Outlet Devices
#1
Primary
660.91'
24.0" Round Culvert L= 65.3' Ke= 0.500
Inlet / Outlet Invert= 660.91' / 660.50' S= 0.0063'/' Cc= 0.900
n= 0.012, Flow Area= 3.14 sf
#2
Device 1
662.50'
3.0" Vert. Orifice/Grate C= 0.600
#3
Device 1
669.35'
16.0' long x 0.5' breadth Broad -Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00
Coef. (English) 2.80 2.92 3.08 3.30 3.32
#4
Device 1
665.50'
14.0" Vert. Orifice/Grate C= 0.600
#5
Device 1
667.00'
8.0" Vert. Orifice/Grate C= 0.600
Primary OutFlow Max=1.91 cfs @ 13.44 hrs HW=666.10' (Free Discharge)
L1=Culvert (Passes 1.91 cfs of 30.97 cfs potential flow)
2=Orifice/Grate (Orifice Controls 0.44 cfs @ 8.98 fps)
3=Broad-Crested Rectangular Weir ( Controls 0.00 cfs)
=Orifice/Grate (Orifice Controls 1.47 cfs @ 2.64 fps)
=Orifice/Grate ( Controls 0.00 cfs)

Wet Pond #2 071219 Charlotte 24-hr 1-yr 1 yr Rainfall=2.58"
Prepared by Microsoft Printed 8/27/2019
HydroCAD® 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 4
Pond 33P: Wet Pond # 2
Hydrograph
■ Inflow
Primary
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)

Wet Pond #2 071219 Charlotte 6-hr 2-yr 2 yr Rainfall=2.28"
Prepared by Microsoft Printed 8/27/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 5
Summary for Subcatchment 4S: POST WP #2
Runoff = 23.48 cfs @ 3.40 hrs, Volume= 1.511 af, Depth= 1.26"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs
Charlotte 6-hr 2-yr 2 yr Rainfall=2.28"
Area (ac) CN Description
14.340 89 Post -Development
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
18.3
150
0.0600
0.14
Sheet Flow, SHEET
Woods: Light underbrush n= 0.400 P2= 3.50"
5.0
250
0.0280
0.84
Shallow Concentrated Flow, SHALLOW CONCENTRATED
Woodland Kv= 5.0 fps
0.1
30
0.0830
8.99
71.92 Channel Flow, CHANNEL
Area= 8.0 sf Perim= 16.0' r= 0.50' n= 0.030
23.4 430 Total
Subcatchment 4S: POST WP #2
Hydrograph
� Runoff
23' Charlotte 6-hr
22
21
20_ = 2-yr
18 2 yr Rai'nfall=2.28"
17,
16= Runoff Area=14.340 ac
w 15 14Runoff Volume=1.511 of
v ;
3 13
12- Runoff Depth=1.26"
u 11_
100 Flow Len gth=430'
Tc=23.4 m i n
5:
CN=89
Time (hours)

Wet Pond #2 071219 Charlotte 6-hr 2-yr 2 yr Rainfall=2.28"
Prepared by Microsoft Printed 8/27/2019
HydroCAD® 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 6
Summary for Pond 33P: Wet Pond # 2
Inflow Area = 14.340 ac, Inflow Depth = 1.26" for 2 yr event
Inflow = 23.48 cfs @ 3.40 hrs, Volume= 1.511 of
Outflow = 2.54 cfs @ 4.56 hrs, Volume= 1.511 af, Atten= 89%, Lag= 69.9 min
Primary = 2.54 cfs @ 4.56 hrs, Volume= 1.511 of
Routing by Stor-Ind method, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs / 3
Peak Elev= 666.24' @ 4.56 hrs Surf.Area= 15,882 sf Storage= 49,172 cf
Plug -Flow detention time= 863.2 min calculated for 1.511 of (100% of inflow)
Center -of -Mass det. time= 863.7 min ( 1,093.4 - 229.8 )
Volume
Invert Avail.Storage
Storage
Description
#1
662.50' 143,325 cf
Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation
Surf.Area Inc.Store
Cum.Store
(feet)
(sq-ft) (cubic -feet)
(cubic -feet)
662.50
10,000
0
0
663.00
11,300
5,325
5,325
664.00
12,700
12,000
17,325
665.00
14,000
13,350
30,675
666.00
15,500
14,750
45,425
667.00
17,100
16,300
61,725
668.00
18,700
17,900
79,625
669.00
20,300
19,500
99,125
670.00
22,100
21,200
120,325
671.00
23,900
23,000
143,325
Device Routinq Invert Outlet Devices
#1
Primary
660.91'
24.0" Round Culvert L= 65.3' Ke= 0.500
Inlet / Outlet Invert= 660.91' / 660.50' S= 0.0063'/' Cc= 0.900
n= 0.012, Flow Area= 3.14 sf
#2
Device 1
662.50'
3.0" Vert. Orifice/Grate C= 0.600
#3
Device 1
669.35'
16.0' long x 0.5' breadth Broad -Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00
Coef. (English) 2.80 2.92 3.08 3.30 3.32
#4
Device 1
665.50'
14.0" Vert. Orifice/Grate C= 0.600
#5
Device 1
667.00'
8.0" Vert. Orifice/Grate C= 0.600
Primary OutFlow Max=2.54 cfs @ 4.56 hrs HW=666.24' (Free Discharge)
L1=Culvert (Passes 2.54 cfs of 31.47 cfs potential flow)
2=Orifice/Grate (Orifice Controls 0.45 cfs @ 9.15 fps)
3= B road-C rested Rectangular Weir ( Controls 0.00 cfs)
=Orifice/Grate (Orifice Controls 2.09 cfs @ 2.93 fps)
=Orifice/Grate ( Controls 0.00 cfs)

Wet Pond #2 071219 Charlotte 6-hr 2-yr 2 yr Rainfall=2.28"
Prepared by Microsoft Printed 8/27/2019
HydroCAD® 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 7
Pond 33P: Wet Pond # 2
Hydrograph
■ Inflow
® Primary
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)

Wet Pond #2 071219 Charlotte 6-hr 10-yr 10 yr Rainfall=3.72"
Prepared by Microsoft Printed 8/27/2019
HydroCAD® 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 8
Summary for Subcatchment 4S: POST WP #2
Runoff = 44.77 cfs @ 3.38 hrs, Volume= 3.061 af, Depth= 2.56"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs
Charlotte 6-hr 10-yr 10 yr Rainfall=3.72"
Area (ac) CN Description
14.340 89 Post -Development
Tc
Length
Slope
Velocity Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec) (cfs)
18.3
150
0.0600
0.14
Sheet Flow, SHEET
Woods: Light underbrush n= 0.400 P2= 3.50"
5.0
250
0.0280
0.84
Shallow Concentrated Flow, SHALLOW CONCENTRATED
Woodland Kv= 5.0 fps
0.1
30
0.0830
8.99 71.92
Channel Flow, CHANNEL
Area= 8.0 sf Perim= 16.0' r= 0.50' n= 0.030
23.4 430 Total
N
3
0
LL
50
42
18
16
14
12
10
Subcatchment 4S: POST WP #2
Hydrograph
Charlotte 6-hr 10-yr
10 yr Rai',nfall=3.72"
Runoff Area=14.340 ac
Runoff Volume=3.061 of
Runoff Depth=2.56"
Flow Length=430'
Tc=23.4 m i n
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)
0 Runoff

Wet Pond #2 071219 Charlotte 6-hr 10-yr 10 yr Rainfall=3.72"
Prepared by Microsoft Printed 8/27/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 9
Summary for Pond 33P: Wet Pond # 2
Inflow Area = 14.340 ac, Inflow Depth = 2.56" for 10 yr event
Inflow = 44.77 cfs @ 3.38 hrs, Volume= 3.061 of
Outflow = 9.74 cfs @ 4.04 hrs, Volume= 3.061 af, Atten= 78%, Lag= 39.3 min
Primary = 9.74 cfs @ 4.04 hrs, Volume= 3.061 of
Routing by Stor-Ind method, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs / 3
Peak Elev= 668.25' @ 4.04 hrs Surf.Area= 19,096 sf Storage= 84,303 cf
Plug -Flow detention time= 485.3 min calculated for 3.061 of (100% of inflow)
Center -of -Mass det. time= 485.2 min ( 709.7 - 224.4 )
Volume Invert
Avail.Storage Storage Description
#1 662.50'
143,325 cf Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation Surf.Area
Inc.Store Cum.Store
(feet)
(sq-ft)
(cubic -feet) (cubic -feet)
662.50
10,000
0 0
663.00
11,300
5,325 5,325
664.00
12,700
12,000 17,325
665.00
14,000
13,350 30,675
666.00
15,500
14,750 45,425
667.00
17,100
16,300 61,725
668.00
18,700
17,900 79,625
669.00
20,300
19,500 99,125
670.00
22,100
21,200 120,325
671.00
23,900
23,000 143,325
Device Routing
Invert
Outlet Devices
#1 Primary
660.91'
24.0" Round Culvert L= 65.3' Ke= 0.500
Inlet / Outlet Invert= 660.91' / 660.50' S= 0.0063 T Cc= 0.900
n= 0.012, Flow Area= 3.14 sf
#2 Device 1
662.50'
3.0" Vert. Orifice/Grate C= 0.600
#3 Device 1
669.35'
16.0' long x 0.5' breadth Broad -Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00
Coef. (English) 2.80 2.92 3.08 3.30 3.32
#4 Device 1
665.50'
14.0" Vert. Orifice/Grate C= 0.600
#5 Device 1
667.00'
8.0" Vert. Orifice/Grate C= 0.600
Primary OutFlow Max=9.74 cfs @ 4.04 hrs HW=668.25' (Free Discharge)
L1=Culvert (Passes 9.74 cfs of 38.08 cfs potential flow)
2=Orifice/Grate (Orifice Controls 0.56 cfs @ 11.42 fps)
3=Broad-Crested Rectangular Weir ( Controls 0.00 cfs)
=Orifice/Grate (Orifice Controls 7.57 cfs @ 7.08 fps)
=Orifice/Grate (Orifice Controls 1.61 cfs @ 4.60 fps)

Wet Pond #2 071219 Charlotte 6-hr 10-yr 10 yr Rainfall=3.72"
Prepared by Microsoft Printed 8/27/2019
HydroCAD® 10.00-22 s/n 05047 0 2018 HydroCAD Software Solutions LLC Page 10
Pond 33P: Wet Pond # 2
Hydrograph
■ Inflow
® Primary
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)

Wet Pond #2 071219 Charlotte 6-hr 25-yr 25 yr Rainfall=4.38"
Prepared by Microsoft Printed 8/27/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 11
Summary for Subcatchment 4S: POST WP #2
Runoff = 54.91 cfs @ 3.35 hrs, Volume= 3.802 af, Depth= 3.18"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs
Charlotte 6-hr 25-yr 25 yr Rainfall=4.38"
Area (ac) CN Description
14.340 89 Post -Development
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
18.3
150
0.0600
0.14
Sheet Flow, SHEET
Woods: Light underbrush n= 0.400 P2= 3.50"
5.0
250
0.0280
0.84
Shallow Concentrated Flow, SHALLOW CONCENTRATED
Woodland Kv= 5.0 fps
0.1
30
0.0830
8.99
71.92 Channel Flow, CHANNEL
Area= 8.0 sf Perim= 16.0' r= 0.50' n= 0.030
23.4 430 Total
Subcatchment 4S: POST WP #2
Hydrograph
Runoff
45
40-
m 35
30-
U.
25-
20
15-
10-
Charlotte 6-hr
25-yr
25 yr Rainfall=4.38"
Runoff Area=14.340 ac
Runoff Volume=3.802 of
Runoff Depth=3.18"
Flow Length=430'
Tc=23.4 min
CN=89
0-
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)

Wet Pond #2 071219 Charlotte 6-hr 25-yr 25 yr Rainfall=4.38"
Prepared by Microsoft Printed 8/27/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 12
Summary for Pond 33P: Wet Pond # 2
Inflow Area = 14.340 ac, Inflow Depth = 3.18" for 25 yr event
Inflow = 54.91 cfs @ 3.35 hrs, Volume= 3.802 of
Outflow = 11.98 cfs @ 3.99 hrs, Volume= 3.802 af, Atten= 78%, Lag= 38.6 min
Primary = 11.98 cfs @ 3.99 hrs, Volume= 3.802 of
Routing by Stor-Ind method, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs / 3
Peak Elev= 669.19' @ 3.99 hrs Surf.Area= 20,650 sf Storage= 103,106 cf
Plug -Flow detention time= 416.4 min calculated for 3.802 of (100% of inflow)
Center -of -Mass det. time= 416.4 min ( 637.2 - 220.8 )
Volume
Invert Avail.Storage
Storage
Description
#1
662.50' 143,325 cf
Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation
Surf.Area Inc.Store
Cum.Store
(feet)
(sq-ft) (cubic -feet)
(cubic -feet)
662.50
10,000
0
0
663.00
11,300
5,325
5,325
664.00
12,700
12,000
17,325
665.00
14,000
13,350
30,675
666.00
15,500
14,750
45,425
667.00
17,100
16,300
61,725
668.00
18,700
17,900
79,625
669.00
20,300
19,500
99,125
670.00
22,100
21,200
120,325
671.00
23,900
23,000
143,325
Device Routing Invert Outlet Devices
#1
Primary
660.91'
24.0" Round Culvert L= 65.3' Ke= 0.500
Inlet / Outlet Invert= 660.91' / 660.50' S= 0.0063 '/' Cc= 0.900
n= 0.012, Flow Area= 3.14 sf
#2
Device 1
662.50'
3.0" Vert. Orifice/Grate C= 0.600
#3
Device 1
669.35'
16.0' long x 0.5' breadth Broad -Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00
Coef. (English) 2.80 2.92 3.08 3.30 3.32
#4
Device 1
665.50'
14.0" Vert. Orifice/Grate C= 0.600
#5
Device 1
667.00'
8.0" Vert. Orifice/Grate C= 0.600
Primary OutFlow Max=11.98 cfs @ 3.99 hrs HW=669.19' (Free Discharge)
L1=Culvert (Passes 11.98 cfs of 40.83 cfs potential flow)
2=Orifice/Grate (Orifice Controls 0.61 cfs @ 12.34 fps)
3=Broad-Crested Rectangular Weir ( Controls 0.00 cfs)
=Orifice/Grate (Orifice Controls 9.08 cfs @ 8.49 fps)
=Orifice/Grate (Orifice Controls 2.29 cfs @ 6.57 fps)

Wet Pond #2 071219 Charlotte 6-hr 25-yr 25 yr Rainfall=4.38"
Prepared by Microsoft Printed 8/27/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 13
3
0
LL
Pond 33P: Wet Pond # 2
Hydrograph
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)
■ Inflow
113 Primary

Wet Pond #2 071219 Charlotte 6-hr 50-yr 50 yr Rainfall=4.92"
Prepared by Microsoft Printed 8/27/2019
HydroCAD® 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 14
Summary for Subcatchment 4S: POST WP #2
Runoff = 62.36 cfs @ 3.35 hrs, Volume= 4.416 af, Depth= 3.70"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs
Charlotte 6-hr 50-yr 50 yr Rainfall=4.92"
Area (ac) CN Description
14.340 89 Post -Development
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
18.3
150
0.0600
0.14
Sheet Flow, SHEET
Woods: Light underbrush n= 0.400 P2= 3.50"
5.0
250
0.0280
0.84
Shallow Concentrated Flow, SHALLOW CONCENTRATED
Woodland Kv= 5.0 fps
0.1
30
0.0830
8.99
71.92 Channel Flow, CHANNEL
Area= 8.0 sf Perim= 16.0' r= 0.50' n= 0.030
23.4 430 Total
45
H 40
Subcatchment 4S: POST WP #2
6 0 40 50 .0 70
Hydrograph
Charlotte 6-hr
50-yr
50 yr Rainfall=4.92"
Runoff Area=14.340 ac
Runoff Volume=4.416 of
Runoff Depth=3.70"
Flow Length=430'
Tc=23.4 m i n
CN=89
80 90 100 110 120 130 140 150 160 170
Time (hours)
Runoff

Wet Pond #2 071219 Charlotte 6-hr 50-yr 50 yr Rainfall=4.92"
Prepared by Microsoft Printed 8/27/2019
HydroCAD® 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 15
Summary for Pond 33P: Wet Pond # 2
Inflow Area = 14.340 ac, Inflow Depth = 3.70" for 50 yr event
Inflow = 62.36 cfs @ 3.35 hrs, Volume= 4.416 of
Outflow = 21.03 cfs @ 3.80 hrs, Volume= 4.416 af, Atten= 66%, Lag= 27.1 min
Primary = 21.03 cfs @ 3.80 hrs, Volume= 4.416 of
Routing by Stor-Ind method, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs / 3
Peak Elev= 669.66' @ 3.80 hrs Surf.Area= 21,494 sf Storage= 112,984 cf
Plug -Flow detention time= 370.2 min calculated for 4.416 of (100% of inflow)
Center -of -Mass det. time= 370.6 min ( 590.7 - 220.0 )
Volume
Invert Avail.Storage
Storage
Description
#1
662.50' 143,325 cf
Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation
Surf.Area Inc.Store
Cum.Store
(feet)
(sq-ft) (cubic -feet)
(cubic -feet)
662.50
10,000
0
0
663.00
11,300
5,325
5,325
664.00
12,700
12,000
17,325
665.00
14,000
13,350
30,675
666.00
15,500
14,750
45,425
667.00
17,100
16,300
61,725
668.00
18,700
17,900
79,625
669.00
20,300
19,500
99,125
670.00
22,100
21,200
120,325
671.00
23,900
23,000
143,325
Device Routinq Invert Outlet Devices
#1
Primary
660.91'
24.0" Round Culvert L= 65.3' Ke= 0.500
Inlet / Outlet Invert= 660.91' / 660.50' S= 0.0063 '/' Cc= 0.900
n= 0.012, Flow Area= 3.14 sf
#2
Device 1
662.50'
3.0" Vert. Orifice/Grate C= 0.600
#3
Device 1
669.35'
16.0' long x 0.5' breadth Broad -Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00
Coef. (English) 2.80 2.92 3.08 3.30 3.32
#4
Device 1
665.50'
14.0" Vert. Orifice/Grate C= 0.600
#5
Device 1
667.00'
8.0" Vert. Orifice/Grate C= 0.600
Primary OutFlow Max=20.97 cfs @ 3.80 hrs HW=669.66' (Free Discharge)
L1=Culvert (Passes 20.97 cfs, of 42.12 cfs potential flow)
2=Orifice/Grate (Orifice Controls 0.63 cfs @ 12.77 fps)
3= B road-C rested Rectangular Weir (Weir Controls 8.04 cfs @ 1.60 fps)
4=Orifice/Grate (Orifice Controls 9.74 cfs @ 9.11 fps)
=Orifice/Grate (Orifice Controls 2.57 cfs @ 7.35 fps)

Wet Pond #2 071219 Charlotte 6-hr 50-yr 50 yr Rainfall=4.92"
Prepared by Microsoft Printed 8/27/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 16
Pond 33P: Wet Pond # 2
Hydrograph
■ Inflow
® Primary
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)

Wet Pond #2 071219 Charlotte 6-hr 100-yr 100 yr Rainfall=5.34"
Prepared by Microsoft Printed 8/27/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 17
Summary for Subcatchment 4S: POST WP #2
Runoff = 69.60 cfs @ 3.35 hrs, Volume= 4.897 af, Depth= 4.10"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs
Charlotte 6-hr 100-yr 100 yr Rainfall=5.34"
Area (ac) CN Description
' 14.340 89 Post -Development
Tc
Length
Slope
Velocity Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec) (cfs)
18.3
150
0.0600
0.14
Sheet Flow, SHEET
Woods: Light underbrush n= 0.400 P2= 3.50"
5.0
250
0.0280
0.84
Shallow Concentrated Flow, SHALLOW CONCENTRATED
Woodland Kv= 5.0 fps
0.1
30
0.0830
8.99 71.92
Channel Flow, CHANNEL
Area= 8.0 sf Perim= 16.0' r= 0.50' n= 0.030
23.4 430 Total
Subcatchment 4S: POST WP #2
Hydrograph
Runoff
'U-
Charlotte 6-hr
65
6°
100-yr
55
100 yr Rainfall=5.34"
50
Runoff Area=14.340 ac
w 45:
40
Runoff Volume=4.897 of
35
Runoff Depth=4.10"
30
Flow Length=430'
25-
20
Tc=23.4 m i n
15
CN=89
10_
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)

Wet Pond #2 071219 Charlotte 6-hr 100-yr 100 yr Rainfall=5.34"
Prepared by Microsoft Printed 8/27/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 18
Summary for Pond 33P: Wet Pond # 2
Inflow Area = 14.340 ac, Inflow Depth = 4.10" for 100 yr event
Inflow
= 69.60 cfs @
3.35 hrs, Volume=
4.897 of
Outflow
= 31.35 cfs @
3.69 hrs, Volume=
4.897 af, Atten= 55%, Lag= 20.5 min
Primary
= 31.35 cfs @
3.69 hrs, Volume=
4.897 of
Routing by
Stor-Ind method, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs / 3
Peak Elev=
669.87' @ 3.69 hrs
Surf.Area= 21,862 sf
Storage= 117,415 cf
Plug -Flow detention time= 338.4 min calculated for 4.897 of (100% of inflow)
Center -of -Mass det. time= 338.4 min ( 557.7 - 219.3 )
Volume
Invert Avail.Storage Storage
Description
#1
662.50'
143,325 cf Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation
Surf.Area
Inc.Store
Cum.Store
(feet)
(sq-ft)
(cubic -feet)
(cubic -feet)
662.50
10,000
0
0
663.00
11,300
5,325
5,325
664.00
12,700
12,000
17,325
665.00
14,000
13,350
30,675
666.00
15,500
14,750
45,425
667.00
17,100
16,300
61,725
668.00
18,700
17,900
79,625
669.00
20,300
19,500
99,125
670.00
22,100
21,200
120,325
671.00
23,900
23,000
143,325
Device Routinq Invert Outlet Devices
#1
Primary
660.91'
24.0" Round Culvert L= 65.3 Ke= 0.500
Inlet / Outlet Invert= 660.91' / 660.50' S= 0.0063 '/' Cc= 0.900
n= 0.012, Flow Area= 3.14 sf
#2
Device 1
662.50'
3.0" Vert. Orifice/Grate C= 0.600
#3
Device 1
669.35'
16.0' long x 0.5' breadth Broad -Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00
Coef. (English) 2.80 2.92 3.08 3.30 3.32
#4
Device 1
665.50'
14.0" Vert. Orifice/Grate C= 0.600
#5
Device 1
667.00'
8.0" Vert. Orifice/Grate C= 0.600
Primary OutFlow Max=31.28 cfs @ 3.69 hrs HW=669.87' (Free Discharge)
t-1=Culvert (Passes 31.28 cfs of 42.67 cfs potential flow)
2=Orifice/Grate (Orifice Controls 0.64 cfs @ 12.96 fps)
3=Broad-Crested Rectangular Weir (Weir Controls 17.95 cfs @ 2.17 fps)
=Orifice/Grate (Orifice Controls 10.01 cfs @ 9.37 fps)
=Orifice/Grate (Orifice Controls 2.68 cfs @ 7.66 fps)

Wet Pond #2 071219 Charlotte 6-hr 100-yr 100 yr Rainfall=5.34"
Prepared by Microsoft Printed 8/27/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 19
3
0
LL
Pond 33P: Wet Pond # 2
Hydrograph
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)
■ Inflow
® Primary