SW3190505_Calcs_20190607

YARBROUGH -WILLIAMS& HOULE, INC.
Planning • Surveying • Engineering
NCBELS C-0475
SC COA332
STORMWATER MANAGEMENT
CALCULATIONS
FOR
The Courtvards on Lawyers Road
FAV I
7637 °
IL t.,
T . U
May 24, 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 • P.O. Box 1198, Pineville, NC 28134 • 704.556.1990 • fax [phone]

STORM DRAINAGE
CALCULATIONS

ON LAWYERS ROAD
REV.
PROJECT
NAME:
THE COURTYARDS
STORM DRAINAGE
CALCULATIONS
P. O .BOX 7007
CHARLOTTE, N.C. 28241
Phone: [phone]
YARBROUGH-WILLIAMS & HOULE�
Planning • Surveying • Engineering
INC.
REV.
REV.
REV.
VERSION 7.26.13
DATE:
JANUARY
15, 2019
SLOPE
%
9.25
2.24
5
0.97
0.50
0.50
0.50
0.50
0.50
0.50
0.50
0.97
0.50
1.52
1.57
1.84
1.57
1.33
0.50
0.50
0.50
0.50
0.50
0.50
0.50
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.80
0.97
0.50
0.50
Fax: [phone]
SURFACE LATERAL
DRAINAGE PIPES
AREA AREA
17.33
3.33
4
0.63
1.10
4.85
2.09
1.24
4.85
0.29
1.65
5.78
1.70
0.70
0.69
0.64
0.39
0.50
0.39
0.34 0.77
0.08 0.35
0.14 0.34
0.38 0.83
0.12 0.32
0.19 0.49
0.18 0.46
0.16 1.98
DRAINAGE
AREA
TOTAL
17.33
20.66
21.72
22.82
22.82
22.82
22.82
22.82
27.67
209
3.33
4.85
0.29
1.94
7.72
8.87
9.57
10.26
10.26
10.26
10.26
10.26
10.26
10.26
0.64
0.64
0.39
0.89
1.28
2.39
2.82
3.30
4.51
4.95
5.63
6.27
8.41
OUTPUT FOR SUBMITTAL
DESIGN RUNOFF SECTION ACCUM. Tc
FREQUENCY MANNING'S COEFF. FLOW TIME FLOW TIME USED
10/25/50/100 n C MINUTES MINUTES MINUTES
012 0.40 0.01 43.00 43.00
012 0.40 0.16 43.01 43.01
.4 4
a5O.012 0.40 0.14 43.44 43.44
25 0.012 0.40 0.08 43.58 43.58
25 0.012 0.40 0.23 43.66 43.66
25 0.012 0.40 0.16 43.89 43.89
25 0.012 0.40 0.27 44.05 44.05
25 0. 112 0.40 0.41 44.32 44.32
25 0.012 0.40 0.18 44.73 44.7373.43
50 0.012 0.60 0.23 5.00 500
50 0.012 0.60 0.29 5.23 5.23
25 0.012 0.40 0.74
50 0.012 0.60 0.08M35.8735.87
25 0.012 0.40 0.42
25 0.012 0.40 0.28
25 0.012 0.40 0.29 36.15 36.15
25 0.012 0.40 0.32 36.44 36.44
25 0.012 0.40 0.51 36.75 36.75
25 0.012 0.40 0.30 37.26 37.26
25 0.012 0.40 0.23 37.56 37.56
25 0.012 0.40 0.19 37.78 37.78
25 0.012 0.40 0.24 37.98 37.98
25 0.012 0.40 0.22 38.21 38.21
25 0.012 0.40 0.1275.67
50 0.012 0.60 0.67
50 0.012 0.60 0.23
d;E
10 0.012 0.60 0.10 5.00 5.00
10 0.012 0.60 0.15 5.10 5.10
10 0.012 0.60 0.08 5.25 5.25
10 0.012 0'60 0.14 5.33 5.33
10 0.012 0.60 0.28 5.47 5.47
10 0.012 0.60 0.75 5.75 5.75
10 0.012 0.60 0.26 6.51 6.51
10 0.012 0.60 0.35 6.77 6.77
10 0.012 0.60 0.25 7.12 7.12
10 0.012 0.60 0.24 7.36 7.36
10 1 0.012 0.60 1 0.16 7.60 7.60
RAINFALL
INTENSITY
10,25,50,100
3.53
3.53
5
3.53
3.53
3.53
3.53
3.43
3.43
8.85
9.00
3.96
3.91
3.91
3.86
3.86
3.86
3.82
3.82
3.82
3.82
3.77
7.03
6.91
6.91
6.91
6.91
6.79
6.55
6.55
6.44
6.44
6.32
RUNOFF
Q(CFS)
24.46
29.16
30.65
32.20
32.20
32.20
31.33
31.33
37.99
11.29
17.68
26.19
0.46
3.04
12. 88
13.71
14.79
15.86
15.66
15.66
15.66
15.66
15.46
15.46
3.46
3.34
1.65
3.69
5.31
9.91
11.69
13.45
17.74
19.47
21.74
24.21
31.87
FES / HW
Q MAX
HW/D: 1.2
49.32
31.27
PIPE
DIAMETER
REQUIRED
15.79
22.00
26.23
30.25
30.25
30.25
29.94
29.94
32.18
20.42
21.34
27.99
4.99
10.07
16.41
17.72
18.82
23.19
23.08
23.08
23.08
23.08
22.97
22.97
12.14
12.50
9.58
12.97
14.87
18.79
19.99
21.07
23.37
22.95
23.07
27.18
30.13
PIPE
DIAMETER
DESIGNED
36
36
36
36
36
36
36
36
36
24
24
30
15
15
24
24
30
30
30
30
30
30
30
30
15
15
15
15
15
24
24
24
24
24
30
30
36
AREA
OF
FLOW (SF)
1.23
2.29
3.17
4.25
4.25
4.25
4.16
4.16
4.86
1.93
2.12
3.67
0.13
0.13
1.25
1.45
1.65
2.52
2.45
2.45
2.45
2.45
2.45
2.45
0.69
0.72
0.43
0.78
1.06
1.65
1.85
2.08
2.60
2.49
2.45
3.44
4.25
WETTED
PERIMETER
FT
2.17
3.39
5.
4.33
5.46
5.46
5.46
5.37
5.37
612
3.71
4.02
5.50
0.63
1.61
2.64
2.95
2.90
4.00
3.93
3.93
3.93
3.93
3.93
3.93
2.16
2.24
1.49
2.39
3.18
3.27
3.58
3.96
4.84
4.65
3.93
5.18
5.46
DESIGN
VELOCITY
FPS
19.91
12.73
7.4
9.65
7.58
7.58
7.58
7.53
7.53
7.81
5.85
8.33
7.14
3.62
6.41
9.65
9.45
8.96
6.30
6.38
6.38
6.38
6.38
6.30
6.30
5.00
4.62
3.84
4.71
4.98
6.00
6.32
6.45
6.83
7.81
8.86
7.04
7.50
FROM
STRUCTURE
STRUCTURE
TYPE
TO
STRUCTURE
PIPE
COVER
AT STRUCT.
LENGTH
FEET
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
2.6
5.5
8.00
124.88
82.59
36.80
74.41
74.41
120.72
184.95
85.91
137
13
DI
DI
13
2
2.0
4.2
81.57
142.45
12
HW
10
34.09
15
16
17
18
19
20
21
22
23
24
25
25A
DI
DI
DI
DI
DI
DI
MH
MH
MH
MH
MH
MH
16
17
18
19
20
21
22
23
24
25
25A
256
1.0
1.0
1.0
1.0
1.0
0.6
3.5
2.1
3.4
3.3
1.3
1.7
161.67
163.27
163.20
162.00
169.52
192.49
113.58
87.29
73.10
90.86
81.73
44.23
26
27
DI
MH
27
28
2.0
1.0
200.45
64.00
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
4.1
3.8
2.6
2.3
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

LTHEOURTYARDS OI ERS ROAD
P.
CHARL41REV.
Phone0Planning
YARBROUGH-WILLIAMS & HOULE,
• Surveying • EngineerinK
INC.
REV.
REV.DATE:
REV.Fax:
PROJECT
NAME:
STORM DRAINAGE
CALCULATIONS
VERSIOI�I 7.26.13
JANUARY15,2019
LENGTH
FEET
47.73
24.00
50.00
187.71
266.27
166.27
112.58
24.00
216.00
216.00
143.42
24.00
81.00
24.00
59.18
24.00
24.00
24.00
24.00
24.00
24.00
24.00
24.00
24.00
24.00
SLOPE
%
0.50
0.50
0.50
0.85
0.95
1.08
1.51
0.60
0.88
0.87
0.84
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.60
1.60
0.60
0.60
0.60
0.60
SURFACE
DRAINAGE
AREA
0.11
0.45
0.65
0.23
0.53
0.71
0.51
0.39
0.31
0.48
0.48
0.26
0.31
0.33
0.11
0.49
0.48
0.46
0.49
0.32
0.35
0.35
0.34
0.35
0.40
LATERAL DRAINAGE
PIPES AREA
AREA TOTAL
3.64 12.16
12.61
0.30 13.56
al.47
0.39
0.70
0.49 1.67
0.48 2.63
0.44 3.33
3.64
0.33
0.44
0.49
0.48
0.46
0.49
0.32
0.48
0.83
0.34
0.35
EO.
OUTPUT
DESIGN
FREQUENCY
10/25/50/100
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10 1
MANNING'S
n
0.012
0.012
0.012
0.012
0.012
0012
0.012
0.012
0.012
0.012
0.012
0.012
0.012
0.012
0.012
0.012
0.012
0.012
0.012
0.012
0.012
0.012
0.012
0.012
0.012
FOR
RUNOFF
COEFF.
C
0.60
0.60
0.60
0.60
0.60
060
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.60
SUBMITTAL
SECTION ACCUM.
FLOW TIME FLOW TIME
MINUTES MINUTES
0.05 7.86
0.05 7.86
0.10 7.91
0.86 5.00
0.68 5.86
043 654
0.24 6.97
0.10 5.00
0.70 5.10
0.58 5.81
0.35 6.39
0.06 6.73
0.20 6.80
0.11 5.00
0.25 5.11
0.10 5.00
0.10 5.00
0.10 5.00
0.10 5.00
0.11 5'00
0.44 5.00
0.09 5.44
0.11 5.00
0.11 5.00
0.11 5.00
Tc
USED
MINUTES
7.76
7.86
7.91
5.00
5.86
...13.74
6.97
5.00
5.10
5.81
6.39
6.73
6.80
5.00
5.11
5.00
5.00
5.00
5.00
5.00
5.00
5.44
5.00
5.00
5.00
RAINFALL
INTENSITY
10,25,50,100
6.32
6.32
6.32
7.03
6.79
6.55
7.03
6.91
6.79
6.67
6.55
6.55
7.03
6.91
7.03
7.03
7.03
7.03
7.03
7.03
6.91
7.03
7.03
7.03
RUNOFF
Q(CFS)
46.08
47.79
51.39
0.97
3.10
7.79
1.65
2.90
6.81
10.53
13.09
14.31
1.39
1.82
2.07
2.02
1.94
2.07
1.35
2.02
3.44
1.43
1.48
1.69
FES / HW
Q MAX
HW/D: 1.2
PIPE
DIAMETER
REQUIRED
34.60
35.07
36.04
7.36
11.15
14.44
9.58
11.04
15.23
18.04
20.86
21.57
9.00
9.96
10.44
10.36
10.19
10.44
8.90
9.29
12.64
9.10
9.20
9.67
PIPE
DIAMETER
DESIGNED
36
36
42
15
15
15
15
15
15
24
24
24
24
15
15
15
15
15
15
15
15
15
15
15
15 1
AREA
OF
FLOW (SF)
5.69
5.84
6.03
0.27
0.58
0.89
0.99
0.43
0.57
1.10
1.53
2.05
2.16
0.38
0.46
0.50
0.50
0.49
0.50
0.38
0.41
0.74
0.40
0.40
0.44
WETTED
PERIMETER
FT
7.07
7.25
6.59
1.06
1.88
2.67
2.94
1.49
1.84
2.39
3.08
3.89
4.08
1.37
1.57
1.69
1.69
1.65
1.69
1.37
1.45
2.28
1.41
1.41
1.53
PIPE
FROM
STRUCTURE
TO
COVER
DESIGN
STRUCTURE
TYPE
STRUCTURE
AT STRUCT.
VELOCITY
FPS
41
41
42
DI
CB
DCB
41
42
43
2.9
2.4
8.5
8.10
8.18
8.53
44
45
46
DI
DI
DI
DI
45
46
47
39
2.0
2.0
2.0
2.0
3.63
5.32
6.5147
6.51
89
48
49
50
51
52
53
DCB
CB
DCB
CB
CB
CB
49
50
51
52
53
40
2.0
2.1
2.0
2.0
2.0
2.3
3.84
5.12
6.21
6.21
88
6.40
6.62
3.64
3.98
4.10
4.01
3.97
4.10
3.53
4.90
4.66
3.61
3.71
3.81
54
55
CB
CB
55
52
2.0
2.1
56
DCB
50
2.0
57
CB
51
2.0
58
DCB
38
2.0
59
DCB
37
2.0
60
DCB
36
2.0
61
62
CB
CB
62
35
2.0
2.0
63
DCB
34
2.0
64
CB
33
2.0
65
CB
66
2.0

PROJECT NAME:
STORM DRAINAGE CALCULATIONS
VERSION 7.26.13
DATE : JANUARY 15, 2019
PIPE
FROM STRUCTURE I TO I COVER
STRUCTURE TYPE I STRUCTURE I ATSTRUCT
THE COURTYARDS ON LAWYERS ROAD
YARBROUGH-WILLIAMS & HOULE, INC.
Planning • Surveying • Engineering
REV.
P. O .Box 7007
REV.
CHARLOTTE, N.C. 28241
REV.
Phone: [phone]
REV.
Fax: [phone]
-
OUTPUT FOR SUBMITTAL
SURFACE LATERAL DRAINAGE DESIGN RUNOFF T 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
I RAINFALL
INTENSITY
10,25,50,100
RUNOFF
Q(CFS)
FES / HW
PIPE
PIPE
AREA
WETTED
DESIGN
Q MAX
HW/D: 1.2
DIAMETER
DIAMETER
OF
PERIMETER
VELOCITY
REQUIRED
DESIGNED I
FLOW (SF) I
FT I
FPS
66
CB
32
2.1
259.24
0.60
0.37
0.77
10
0.012
0.60
0.96
5.11
5.11
6.91
3.19
67
68
69
70
71
72
73
74
75
76
77
78
79
80
80A
81
82
83
84
85
CB
CB
CB
CB
CB
CB
CB
CB
DCB
DCB
DCB
CB
CB
CB
CB
DI
MH
CB
CB
MH
68
69
70
71
72
73
74
75
76
77
78
79
80
80A
81
82
83
84
85
86
2.0
2.1
2.0
2.0
2.3
2.0
2.3
3.1
3.5
3.0
3.3
6.4
6.2
6.3
6.4
7.7
9.5
8.7
7.0
4.5
24.00
105.08
108.00
24.00
130.76
24.00
40.04
24.00
155.12
24.00
367.20
95.99
134.24
24.00
34.83
141.10
235.74
152.26
200.00
22.69
0.60
0.67
0.81
0.60
0.69
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.50
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
0.33
0.82
0.67
0.39
0.20
1 0.19
0.45
0.04
0.10
0.11
0.84
1.17
0.35
0.48
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
5.86
6.53
7.40
8.59
13.11
13.56
19.32
19.48
19.69
20.60
22.99
10
10
10
10
10
10
10
10
10
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
0.012
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
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.11
0.39
0.34
0.08
0.34
0.07
0.10
0.06
0.36
0.05
0.80
0.21
0.30
0.05
0.07
0.26
0.43
0.28
0.37
0.04
5.00
5.11
5.50
5.84
5.92
6.26
6.32
6.43
6.48
6.85
6.90
7.70
7.91
8.20
8.25
8.32
8.58
9.01
9.30
9.66
5.00
5.11
5.50
5.84
5.92
6.26
6.32
6.43
6.48
6.85
6.90
7.70
7.91
8.20
8.25
8.32
8.58
9.01
9.30
9.66
7.03
6.91
6.91
6.79
6.79
6.67
6.67
6.67
6.67
6.55
6.55
6.32
6.32
6.20
6.20
6.20
6.08
5.96
5.96
5.84
1.39
2.70
3.86
4.93
9.78
10.53
22.37
17.46
18.78
23.04
25.68
28.04
32.55
48.75
50.42
71.84
71.04
70.40
73.65
80.56
87
88
88A
89
DI
DI
DI
DI
88
88A
89
74
2.0
2.0
2.0
2.0
231.44
165.13
133.49
137.44
0.86 1
0.85 1
0.90
0.60
.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
6.55
6.67E4.52
6.4490
0.63
HW
71
34.36
4.34
0.84
0.84
10
0.012
0.60
0.06
5.00
5.00
7.03
91
DCB
76
2.0
100.52
1.20 1
0.35
0.35
10
0.012
0.60
0.35
5.00
5.00
7.03
1.48
92
DCB
78
2.0
24.00
0.79
0.48
0.48
10
0.012
0.60
0.09
5.00
5.00
7.03
2.02
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
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
95
96
DI
CB
96
84
3.0
2.0
44.46
24.00
4.09
0.60
0.36
0.44
0.36
0.80
10
10
0.012
0.012
0.60
0.60
0.10
0.09
5.00
5.10
5.00
5.10
7.03
6.91
1.52
3.32
97 DI 98 2.0 47.51 1.96 1.91 1 1 1.91 1 10 0 012 0.60 0.09 7.03 I 8.06
VV ��
12.29 15 1 0.71 2.20 4.52
0.38
1.37
3.64
E1446
a15
0.60
1.92
4.51
0.72
2.24
5.34
0.99
2.94
4.99
18.24
24
1.53
3.08
6.39
19.22
24
1.73
3.39
6.08
20.42
24
1.93
3.71
6.41
23.24
30
2.52
4.00
6.94
23.88
36
2.64
3.77
7.11
25.79
36
3.09
4.24
7.47
26.85
42
3.35
4.18
7.65
27.76
42
3.59
4.40
7.80
30.37
42
4.32
5.06
7.53
35.34
42
5.79
6.37
8.42
35.79
42
5.91
6.48
8.54
40.87
42
7.95
8.46
9.04
40.70
42
7.85
8.35
9.05
40.56
42
7.85
8.35
8.97
41.25
42
8.15
8.68
9.03
42.66
48
8.49
8.04
9.48
6.25
15
0.20
0.86
3.16
10.02
15
0.47
1.61
4.65
11.59
15
0.63
2.00
5.31
14.00
15
0.92
2.75
4.92
0.37
1.33
9.63
M8.08
a150.31
1.18
4.77
9.83
15
0.46
1.57
4.42
11.37
15
0.60
1.92
6.98
5.66
15
0.16
0.75
2.86
6.49
15
0.21
0.90
7.12
12.47
15
0.72
2.24
4.59
13.93
15 1
0.92
2.75
8.78

YARBROUGH-WILLIAMS & HOULE, INC.
Planning • Surveying • Engineering
FOR SUBMITTAL
RUNOFF SECTION ACCUM. Tc RAINFALL
PROJECT NAME :
THE COURTYARDS ON LAWYERS ROAD
STORM DRAINAGE CALCULATIONS
P. O .BOX 7007
W
VERSION 7.26.13
CHARLOTTE, N.C. 28241
DATE:
JANUARY15,2019
Phone: [phone]
PIPE
Fax: [phone]
SURFACE LATERAL DRAINAGE
OUTPUT
DESIGN
FES / HW
PIPE
PIPE
AREA
WETTED
DESIGN
FROM
STRUCTURE
STRUCTURE
TYPE
TO
STRUCTURE
COVER
AT STRUCT.
LENGTH
FEET
SLOPE
%
DRAINAGE
AREA
PIPES
AREA
AREA
TOTAL
FREQUENCY
10125/50/100
MANNING'S
n
COEFF.
C
FLOW TIME
MINUTES
FLOW TIME
MINUTES
USED
MINUTES
INTENSITY
10,25,50,100
RUNOFF
Q(CFS)
Q MAX
HW/D: 1.2
DIAMETER
REQUIRED
DIAMETER
DESIGNED
OF
PERIMETER
VELOCITY
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
5.16
6.91
6.91
9.33
9.91
18.37
15.29
24
24
5.94
1.57
3.14
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
169.39
147.48
99.47
171.19
24.00
39.60
1.18
0.85
1.00
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
0.33
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
0.22
0.47
0.07
0.11
5.00
5.27
5.59
6.04
6.38
6.61
7.08
7.14
5.00
5.27
5.59
6.04
6.38
6.61
7.08
7.14
7.03
6.91
6.79
6.67
6.67
6.55
6.44
6.44
1.35
3.52
6.11
9.37
.85
.7
g14.67
.72
7.83
11.94
14.26
16.76
19.20
221.99
22.53
23.66
15
15
15
0.30
1.14
4.57
0.66
2.08
5.34
0.96
2.87
6.37
18
24
24
1.32
3.30
7.09
1.73
3.39
7.43
2.27
4.27
6.05
24
24
2.39
4.46
6.15
2.66
4.96
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
112
CB
CB
103
104
2.0
2.0
24.00
24.00
0.60
0.60
0.35
0.40
0.35
0.40
10
10
0.012
0.012
0.60
0.60
0.11
0.11
5.00
5.00
5.00
5.00
7.03
7.03
1.48
1.69
9.20
M54
15
0.40
1.41
3.71
15
0.44
1.53
3.81
122
123
124
125
114
115
116
117
118
108
CB
CB
CB
CB
CB
CB
CB
DCB
CB
CB
123
124
125
114
115
116
117
118
108
81
2.0
2.1
2.0
2.3
2.0
2.0
2.0
5.6
5.9
6.2
24.00
162.57
24.00
169.20
112.00
99.99
108.83
55.38
24.00
29.04
0.60
3.02
0.60
2.54
0.94
0.74
0.55
0.50
0.50
0.50
0.64
0.29
0.23
0.16
0.47
0.32
0.28
0.44
0.21
0.18
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
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
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.60
0.09
0.31
0.08
0.30
0.25
0.24
0.28
0.14
0.06
0.07
5.00
5.09
5.40
5.48
5.78
6.03
6.27
6.55
6.69
6.74
5.00
5.09
5.40
5.48
5.78
6.03
6.27
6.55
6.69
6.74
7.03
6.91
6.91
6.91
6.79
6.67
6.67
6.55
6.55
6.55
2.70
3.86
4.81
7.30
11.08
13.49
15.98
19.94
20.76
21.47
14.33
12.78
18.00
20.30
22.84
25.27
25.66
25.98
15
0.61
1.96
4.40
15
15
0.44
1.53
8.70
0.97
2.90
4.94
15
0.77
2.36
9.49
24
24
1.49
3.01
7.44
1.93
3.71
7.00
24
2.46
4.58
6.50
30
30
2.95
4.55
6.75
3.08
4.71
6.75
30
3.14
4.79
6.85
126
DI
125
2.0
33.60
0.60
0.44
0.44
10
0.012
0.60
0.14
5.00
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
119
DCB
117
2.0
24.00
0.60
0.64
0.64 1
10
0.012
0.60 1
6.09
5.00
5.00
7.03
2.70
11.54
15
0.61
1.96
4.40
120
CB
116
2.0
24.00
0.60
0.34
0.34 1
10
0.012
0.60
0.11
5.00
5.00
7.03
1.43
9.10
15
0.40
1.41
3.61

THE COURTYARDS ON LAWYERS ROAD
P. O .BOX 7007
CHARLOTTE, N.C. 28241
Phone: [phone]
Fax: [phone]
YARBROUGH-WILLIAMS & HOULE, INC.
Planning •Surveying •Engineering
PROJECT
NAME
:
REV.
STORM DRAINAGE
CALCULATIONS
REV.
VERSION 7.26.13
REV.
DATE.
JANUARY 15, 2019
REV.
OUTPUT FOR SUBMITTAL
FROM
STRUCTURE
TO
PIPE
COVER
LENGTH
SLOPE
SURFACE
DRAINAGE
LATERAL
PIPES
DRAINAGE
AREA
DESIGN
FREQUENCY
MANNING'S
RUNOFF
COEFF.
SECTION
FLOW TIME
ACCUM. T-
FLOW TIME USED
RAINFALL
INTENSITY
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
STRUCTURE
TYPE
STRUCTURE
AT STRUCT.
FEET
%
AREA
AREA
TOTAL
10/25/50/100
n
C
MINUTES
MINUTES
MINUTES
10,25,50,100
121
CB
115
2.0
24.00
0.60
0.33
0.33
10
0.012
0.60
0.11
5.00
9.00
15
0.38
1.37
3.64
5.00
7.03
1.39
132
133
134
HW
DCB
CB
133
134
135
1.2
1.6
29.97
61.00
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
2.14
2.14
4.40
2.8
12.82
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
1.45
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

0
.. z
s. fsi CIO
C)
O 3
�MM
C
Aa
aO a
4-0
4) o6AeLlosrfl
SDI Oi
I
t .
005'0 r=14MI l t 1 +'
'--�._ tom) aaaeweip
-did
4'1 i �'a M iall�C7
m
M
N

P. O .BOX 7007
CHARLOTTE, N.C. 28241 wl
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 RIPRAP
RIP RAP
OUTLET
STRUCTURE
VEL.
I APRON I
RIP RAP
DEPTH (IN)
FLOW
NO.
FT/SEC
DIMENSIONS
D50(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
6.3
18.5
X
16.0
6.0
10.0
15.5
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 LAWYI
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 I RIP RAP OUTLET
STRUCTURE VEL. APRON RIP RAP DEPTH(IN) FLOW
NO. FT/SEC DIMENSIONS I D 50 (IN) W/ FABRIC CFS
WIDTH I X I LENGTH
1 43 1 8.5 1 25.5 1 X 1 22.0 1 9.0 1 13.5 1 51.4 1

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 I RIP RAP OUTLET
STRUCTURE VEL. APRON I RIP RAP DEPTH (IN) FLOW
NO. FT/SEC DIMENSIONS D 50 (IN) W/ FABRIC CFS
WIDTH I X LENGTH
1 86 1 9.5 1 30.0 1 X 1 26.0 1 12.0 1 18.0 1 80.6 1
90 1 R.R.F.I.P.

Phone: [phone] YARBROUGH-WILLIAMS & HOULE, INC.
Fax: [phone] Planning a 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. I APRON j RIP RAP DEPTH (IN) FLOW
NO. FP/SEC DIMENSIONS. D 50 (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

SPREAD CALCULATIONS

INLET SPREAD CHART ,`'C�`��
Version 9. SP
7.12
730 Windsor Oak Ct.
VGK Charlotte, NC 28273
Project Parameters YARBROUGH-WILLIAMS & HOULE,, INC. Phone: [phone]
Intensity: 4.00 Planning • Surveying • Engineering Fax: [phone]
C: 1 0.60
Crown: 0.0208 1 - 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
SURF Q
BYPASS Q
SURF Q
INLET
BYPASS
SLOPE
AREA AC-
LONG. %
TO INLET =
INLET
K
SUB
RECEIVED
TOTAL
Qcap
QSENT
TRANS-
n
SPREAD
c
REMARK
65
0.40
1.78
100
S
24
0.96
0.00
0.96
0.79
0.17
0.0208
0.016
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
0.77
0.03
0.791
0.70
0.091
0.0208
0.0161
6.3
110
0.33
L 18
1111
S
21
0.79
0.09
0.88
0.75
0.13
0.0208
0.016
6.5
103
0.49
1.18
104
D
21
1.18
0.09
1.27
1.65
0.00
0.0208
0.016
7.5
111
0.35
1.18
112
S
21
0.84
0.13
0.97
0.80
0.18
0.0208
0.016
6.8
104
0A7
1.18
105
S
21
1.13
0.00
L 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
1061
0.30
2.39
119
S
27
0.721
0.17
0.89
0.771
0.11
0.02081
0.016
5.7
107
0.53
2.391
119
D
1 27
1.271
0.26
1.531
1.91
0.00
0.0208
0.016
7.0
78
0.39
1.00
79
S
21
0.94
0.00
0.94
0.82
0.12
0.0208
0.016
6.9
92
0.48
1.00
80A
D
21
1.15
0.00
L 15
1.63
0.00
0.0208
0.016
7.4
79
0.20
1.00
80
S
21
0.48
0.12
0.60
0.62
0.00
0.0208
0.016
5.8
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
0.45
1.00
117
S
21
1.08
0.00
1.08
0.90
0.18
0.0208
0.016
7.2
122
0.64
4.00
125
S
33
1.54
0.00
1.54
L 14
0A01
0.0208
0.016
6.4
123
0.291
4.00
124
S
331
0.70
0.00
0.70
0.69
0.001
0.0208
0.016
4.7
125
0.16
3.00
114
S
30
0.38
0.40
0.78
0.74
0.04
0.0208
0.016
5.2
124
0.23
3.00
113
S
30
0.55
0.00
0.55
0.60
0.00
0.0208
0.016
4.6
114
0.47
2.00
115
S
27
1.13
0.04
1.17
0.97
0.20
0.0208
0.016
6.5
113
0.49
2.00
121
S
27
1.18
0.00
1.18
0.98
0.20
0.0208
0.016
6.6
115
0.32
1.00
116
S
21
0.77
0.20
0.96
0.83
0.13
0.0208
0.016
6.9
121
0.33
1.00
120
S
21
0.79
0.20
0.99
0.85
0.14
0.02081
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
0.341
1.00
1191
S
211
0.82
0.14
0.96
0.83
0.13
0.0208
0.016
6.9
118
0.21
1.20
117
S
211
0.50
0.00
0.50
0.53
0.00
0.0208
0.016
5.3
108
0.18
1.20
117
S
211
0.43
0.00
0.43
0.48
0.00
0.0208
0.016
5.0
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
1.56
84
S
24
0.24
0.00
0.24
0.35
0.00
0.0208
0.016
3.8
96
0.44
1.31
98
S
21
1.06
0.00
1.061
0.81
0.24
0.02081
0.016
6.8
84
0.11
1.31
99
S
21
0.261
0.00
0.26
0.34
0.00
0.0208
0.016
4.1
98
0.341
1.06
1-361
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
0.19
0.0208
0.016
7.1
Inlets at Sag
INLET
DRAINAGE
SURF Q
BYPASS Q
SURF Q
SLOPE
SINGLE _ "S"
DEPTH
9
AREA
SUB
RECEIVED
TOTAL
TRANS.
DOUBLE ="D"
(D)
SPREAD
REMARKS
117
0.44
1.06
0.24
1.30
0.0208
D
0.12
5.60
119
0.64
1.54
0.24
1.78
0.0208
D
0.14
6.89
133
0.66
1.58
0.19
1.77
0.0208
D
0.14
6.88
134
0.56
1.34
0.00
1.34
0.0208
S
0.15
7.26
S
S
S
S
S
S
S
S
S
S
S
S
S

INLET SPREAD CHART
Version 9.27.12
Intensity: I 4.0 1
C: j 0.60
Crown: 1 0.0208 1 -Input 0.0208 or 0.0313
I'�Xh3
YARBROUGH-WILLIAMS & HOULE, INC.
Planning • Surveying • Engineering
cells
WKD I Project Name: ITHE COURTYARDS ON LAWYERS ROAD
730 Windsor Oak Ct.
Charlotte, NC 28273
Phone: [phone]
Fax: [phone]
Date: FEB. 3, 2019
Inlets on Slope
INLET
DRAINAGE
SLOPE
BYPASS
TYPE
SURF
BYPASS
SURFQ
INLET
BYPASS
SLOPE
It
AREA AC
LONG_
TO INLET-
INLET
K
SUB
RECEIVED
TOTAL
Qcap
Q SENT
TRANS
n
SPREAD
REMARKS
0.89
0.00
.
66
037
1.78
48
S
24
0.89
0.76
0.13
0.0208
0.016
6.0
32
0.34
1.06
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
301
0.50
1.08
33
S
21
1.20
0.00
1.20
0.93
0.271
0.0208
0.016
7.4
29
0.39
1.081
64
S
1 21
0,941
0.00
0.94
1 0.80
0.14
0.0208
0.0161
6.8
33
0.08
1.08
34
S
21
0.19
0.48
0.67
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
L 13
0.16
1.28
1.70
0.00
0.0208
0.016
7.6
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
0351
L08
601
S
21
0.84
0.15
0.99
0.83
0.16
0.0209
0.016
6.9
36
0.53
1.08
37
S
211
1.271
0.03
1.30
0.98
0.32
0.02081
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
1.08
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
1.08
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
0.69
0.10
0.0208
0.016
6.6
55
a I 11
1.03
41
S
21
0.26
0.001
0.26
0.37
0.00
0.0208
0.016
4.2
54
0.33
1.03
138
S
211
0.79
0.00
0.79
0.73
0.06
0.02081
0.016
6.4
48
0.39
1.00
561
D
21
0.94
0.13
1.07
1.56
0.00
0.0208
0.0161
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
1.18
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
52
S
21
L 15
0.00
1,151
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
211
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
0,0161
6.4
68
0.32
1.00
69
S
21
0.77
0.00
0.77
0.72
0.04
0.0208
0.016
6A
69
0.28
1.00
70
S
21
0.67
0.04
0.72
0.69
0.02
0.0208
0.016
6.2
70
0.28
1.00
73
S
21
0.671
0.02
0.70
0.68
0.02
0.0208
0.016
6.1
71
0.35
1.00
721
S
21
0.84
0.05
0.89
0.801
0.10
0.0208
6.016
6.7
72
0.23
1.00
77
S
21
0.55
0.10
0.65
0.65
0.00
0.02081
0.016
6.0
73
0.46
1.00
77
S
21
1.10
0.02
L12
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
1.61
0.20
1.81
0.0208
D
0.15
6.98

DROP INLET DEPTH
CALCULATIONS

m
K
a
LO
N
M
O
O
N
O
M
N
O
N
N
ru
d'
V
N
N
M
NC)
c!
00
CO
N
N
3
o
O
000000000000
m
o
Ln
0
nLnLnU')LOLOLOLOLOLOLOU)
0
0
0
0
0
0
0
0
0
0
0
3
a
U
z
S
U
P-.
.�-7
O
a
r
r
W
NN
N
r
W
0
(O0
W0M-
.
WN
MO
(O
O
0
0
0
0
0
0
0
0
0
0
0
O
O
O
U
C
z
o
U)
a
F=
T
co
N
W
M
O
co
r
00
M
(D
V
J
Q
cc�GG3o
W
O.
00000000000
N
O
O
O
N
O
0
0
0
2
Uo
0
O
F
w
v
FS
co
LO
N
0
0
0
N
m
O
N
0
q
c%
a
O
O
O
O
C.
O
O
O
O
O
O
O
O
O
U
U
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
4
CD
K
F�
F
I
B
O
M
O
W
O
o0
O
W
0
CO
0
W
0
W
0
M
0
W
0
00
0
W
O
M
O
W
O
�
3
�
m
a
v
E-
�-
F
z
O'
CO
co
(0
o
o
o
M
0
M
M
cc
co
co
Q
z
o
0
0
o
(0
o
o
0
(0
CO
(0
o
(0
co
M
c+j
Oce
Q
w
U
LO
r
U')
(0
r
O
coo
N
N
M
c0
LO
M
M
N
M
m
O
M
r¢i
ce
O,
NCO
r
N
CO
M
I-
N
00
0
O
0
M
0
r
N
r-
r
co
N
O
F)
N
m
r
co
N
V
m
m
r-
o
V
M
In
r
O
of
M
N
O
f-
m
m
M
M
r
fh
Z
}
~
a
z z
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
Nm
co
W
W
oD
M
M
a0
co
W
W
N
M
M
W
CO
W
W
M
M
W
W
W
co
W
aO
�
z
U
J
-
a
U
2
a
co
M
M
O
O
M
O
co
O
M
M
M
M
co
M
O
Colo
co
O I
O
M
M
O
M
M
O
j
O
M
M
M
M
M
O
O
M
M
M
M
co
CO
M
M
M
M
M
10
O
ID
(0
M
M
M
COW
O
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
❑
W
❑
a
Q
Q
Q
M
N
M
(n
I�
�17
(0
r
r
r
r
O
N
CO
d)
O)
V
O
O)
O
o
M
O't
C'M
CM
o
I-
O
V
V
d)
l0
OD
D7
0
N
0
m
Q
O
Z
Q
w
O
O
O
O
CD
O
O
O
O
O
O
N
O
O
r
O
O
r
N
r
o
O
N
O
o
rLO
r-
r
1-
O
r
O
M
O
J
Ir
aaQ
Q
U)
U)
06
d'
W
W
r
O
`-'�
W
H�HF-F-F•F•H
W
W
W
W
W
W
W
W
W
W
W
W
CO
00
OO
OD
O0
OO
m
m
m
OO
0]
OOP
W
W
LU
m�
aaaaaaaaaaaaa
F•F•Fm�
J
aaaaaagaaaaaaa
J
J
J
J
J
J
J
J
J
J
J
F-z
Q
�
0_'
CC
�
Q_'
of
0_'
a'
�
0_'
��
�.
�
Q.
O
rn
v''i
C�C7C7C7C7C7C�C7C�C�C7�C�
C7(n(ncncncn(ntn(ncn(n(nu��
0<
C7
U
0
❑Of
N
LLJ
a
T
W
W
W
W
W
W
J
W
J
W
J
W
J
W
J
W
J
W
W
W
W
W
W
W
W
W
W
W
W
W
W
W
W
d(D
J
J
J
J
J
J
J
J
J
J
J
J
J
J
J
J
ZH2
�,
r
U`
C7C7U'
(Dd('DU`
CD
CD
C7U'
C7C7U'
U`
C7U'
(DCDC7C
(D(
0-'
U
F
Z_
Z_
Z_
Z_
Z_
Z_
Z_
Z_
Z_
Z_
Z_
Z_
Z_
Z_
Z_
Z_
Z_
Z_
Z_
000
<U)U)U)U)V)U)U)UJ
_Z
_Z
_Z
_Z
U)U)U)U)U)
_Z
V)U)U)U)U)U)V)U)V)U)U)U)U)U)
_Z
_Z
_Z
❑
❑
W
F
V
LO
O
r-
m
O
f�
00
O
M
M
N
M
(O
LL0
(0
f�
M
a1
0
W
Z
LLI
V
V
V
V
M
t
W
CO
W
W
W
r
W
a1
(
r
N
r
r
N
00
°a
z_
cna❑

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 N 6.64, BAFFLE SPACING 30.19
MARLEE
FAIRCLOTH
SKIMMER
REQUIRED
SURFACE AREA
REQUIRED
STORAGE
SKIMMER
SKIMMER
SKIMMER
SKIMMER
theoritical
BASIN
DRAINAGE
DENUDED
410
SURFACE AREA
PROVIDED
STORAGE
VOLUME (CF)
TOP (Min.) BOTTOM (Min.)
DEPTH (FT)
MODEL
ORIFICE
SIZE (IN.)
ORIFICE
HEAD AT
SPILLWAY
HEAD (FT)
TOP OF
SKIMMER
spillway
Tc
NO
AREA (AC.)
AREA (AC.)
Ids)
(sf)
(sf)
VOL. (CF)
PROVIDED
W(ft) X Lift) W(ft) X Lilt)
(H)
DIA. (IN)
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
5839.82
10653.00
6,606
18,724
64
X
168
52
X
155
2
1
1.50
2.00
1.60
0.13
5.0
10
3.0
10.0
0.5
680
0.072
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
1.50
2.00
1.70
0.13
5.0
10
3.0
10.0
0.5
680
0.046
10
5
6
0.75
0.76
3.16
1028.14
3727.00
1,350
6,099
59
X
61
47
X
48
2
NIA
NIA
1.50
0.80
0.00
6.0
10
3.0
10.0
0.5
682
0.024
10
6
7
2.71 1
2.71
11.43
3715.00
4326.00
4,878
6,826
54
X
82
34
X
71
2
1
1.00
1.50
1.50
0.00
5.0
10
3.0
10.0
0.5
679
0.026
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 1,350 Cu.Ft Skimmer Size 1.5 Inch
Days to Drain* 3 Days Orifice Radius 0.4 Inch[es]
Orifice Diameter 0.8 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

Fee Saver
Stormwater Services
Marlee Float Skimmer Size Selection Report
Date
Company
Engineer
Project Name
Project Location
Basin Description
Actual Provided Volume Analysis
Other 2
Other 3
March 5, 2019
Yarbrough, Williams & Houle
Vincent G. Keene PE
COURTYARDS ON LAWYERS ROAD
STALLINGS, NC
Skimmer Basin # 3
Inputs
Calculations
Max. Time to Drain, hrs = 120
Calculated Pond Volume, ft3 = 6,625
Min. Time to Drain, hrs = 48
Pond Depth, ft = 2
Calculated Pond Volume, gal = 49,555
Pond Top Length, ft = 82.5
Pond Top Width, ft = 80
Pond Bottom Length, ft = 30
Pond Bottom Width, ft = 30
Minimum Average Flow Rate Allowable
Maximum Average Flow Rate Allowable
1,325 cfd to drain in
0.015 cfs
3,313 cfd to drain in
0.038 cfs
Marlee Float Selection Chart
Model #
Orifice
Draw down time (hrs)
Acceptable for basin
1
1.0"
110
Model 1 - 1.0" orifice saddle
1
1.5"
60
Model 1 - 1.5" orifice saddle
1
2.0"
34
no
1
2.5"
22
no
2
3.0"
11
no
2
4.0"
8
no
2
5.0"
6
no
3
5.0"
1 4
no
3
1 6.0"
3
no
3 1
8.0" 1
3
no
120 hrs
48 hrs
803 Roper Creek Drive
Greenville, SC 29615
www.SWFeeSaver.com

Fee Saver
Stormwater Services
Marlee Float Skimmer Size Selection Report
Date
Company
Engineer
Project Name
Project Location
Basin Description
Actual Provided Volume Analysis
Other 2
Other 3
March 5, 2019
Yarbrough, Williams & Houle
Vincent G. Keene PE
COURTYARDS ON LAWYERS ROAD
STALLINGS, NC
Skimmer Basin # 5
Inputs
Calculations
Max. Time to Drain, hrs = 120
Calculated Pond Volume, ft3 = 7,419
Min. Time to Drain, hrs = 48
Pond Depth, ft = 2
Calculated Pond Volume, gal = 55,494
Pond Top Length, ft = 71.7
Pond Top Width, ft = 80
Pond Bottom Length, ft = 40
Pond Bottom Width, ft = 50
Minimum Average Flow Rate Allowable
Maximum Average Flow Rate Allowable
1,484 cfd to drain in
0.017 cfs
3,710 cfd to drain in
0.043 cfs
Marlee Float Selection Chart
Model #
Orifice
Draw down time (hrs)
Acceptable for basin
1
1.0"
124
no
1
1.5"
68
Model 1 - 1.5" orifice saddle
1
2.0"
39
no
1
2.5"
25
no
2
3.0"
12
no
2
4.0"
9
no
2
5.0"
7
no
3
5.0"
5
no
3
6.0"
3
no
3
8.0"
3
no
803 Roper Creek Drive
Greenville, SC 29615
www.SWFeeSaver.com
120 hrs
48 hrs

Fee Saver
Stormwater Services
Marlee Float Skimmer Size Selection Report
Date
Company
Engineer
Project Name
Project Location
Basin Description
Actual Provided Volume Analysis
Other 2
Other 3
March 5, 2019
Yarbrough, Williams & Houle
Vincent G. Keene PE
COURTYARDS ON LAWYERS ROAD
STALLINGS, NC
Skimmer Basin # 6
Inputs
Calculations
Max. Time to Drain, hrs = 120
Calculated Pond Volume, ft3 = 1,355
Min. Time to Drain, hrs = 48
Pond Depth, ft = 2
Calculated Pond Volume, gal = 10,135
Pond Top Length, ft = 38.5
Pond Top Width, ft = 40
Pond Bottom Length, ft = 10
Pond Bottom Width, ft = 10
Minimum Average Flow Rate Allowable
Maximum Average Flow Rate Allowable
271 cfd to drain in
0.003 cfs
678 cfd to drain in
0.008 cfs
Marlee Float Selection Chart
Model #
Orifice
Draw down time (hrs)
Acceptable for basin
1
1.0"
23
no
1
1.5"
12
no
1
2.0"
7
no
1
2.5"
5
no
2
3.0"
2
no
2
4.0"
2
no
2
5.0"
1
no
3
5.0"
1
no
3
6.0"
1
no
3
8.0"
1
no
120 hrs
48 hrs
803 Roper Creek Drive
Greenville, SC 29615
www.SWFeeSaver.com

Fee Saver
Stormwater Services
Marlee Float Skimmer Size Selection Report
Date
Company
Engineer
Project Name
Project Location
Basin Description
Actual Provided Volume Analysis
Other 2
Other 3
March 5, 2019
Yarbrough, Williams & Houle
Vincent G. Keene PE
COURTYARDS ON LAWYERS ROAD
STALLINGS, NC
Skimmer Basin # 7
Inputs
Calculations
Max. Time to Drain, hrs = 120
Calculated Pond Volume, ft3 = 4,879
Min. Time to Drain, hrs = 48
Pond Depth, ft = 2
Calculated Pond Volume, gal = 36,495
Pond Top Length, ft = 63
Pond Top Width, ft = 62
Pond Bottom Length, ft = 35
Pond Bottom Width, ft = 35
Minimum Average Flow Rate Allowable
Maximum Average Flow Rate Allowable
976 cfd to drain in 120 hrs
0.011 cfs
2,440 cfd to drain in 48 hrs
0.028 cfs
Marlee Float Selection Chart
Model #
Orifice
Draw down time (hrs)
Acceptable for basin
1
1.0"
82
Model 1 - 1.0" orifice saddle
1
1.5"
45
no
1
2.0"
26
no
1
1 2.5"
16
no
2
3.0"
8
no
2
4.0"
6
no
2
5.0"
5
no
3
5.0"
3
no
3
6.0"
2
no
3
8.0"
2 1
no
803 Roper Creek Drive
Greenville, SC 29615
www.SWFeeSaver.com

EROSION CONTROL
SEDIMENT BASIN
CALCULATIONS

P. O .BOX 7007
CHARLOTTE, N.C. 28241
Phone: [phone]
Fax: [phone] YARBROUGH-WILLIAMS & HOULE, INC.

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

Fee Saver
Stormwater Services
Marlee Float Skimmer Size Selection Report
Date
Company
Engineer
Project Name
Project Location
Basin Description
Actual Provided Volume Analysis
Other 2
Other 3
March 5, 2019
Yarbrough, Williams & Houle
Vincent G. Keene PE
COURTYARDS ON LAWYERS ROAD
STALLINGS, NC
Sediment Basin # 1
Inputs
Calculations
Max. Time to Drain, hrs = 120
Calculated Pond Volume, ft3 = 57,101
Min. Time to Drain, hrs = 48
Pond Depth, ft = 2
Calculated Pond Volume, gal = 427,118
Pond Top Length, ft = 100
Pond Top Width, ft = 379.5
Pond Bottom Length, ft = 80.05
Pond Bottom Width, ft = 250
Minimum Average Flow Rate Allowable
Maximum Average Flow Rate Allowable
11,420 cfd to drain in
0.132 cfs
28,551 cfd to drain in
0.330 cfs
Marlee Float Selection Chart
Model #
Orifice
Draw down time (hrs)
Acceptable for basin
1
1.0"
955
no
1
1.5"
522
no
1
2.0"
303
no
1
2.5"
189
no
2
3.0"
92
Model 2 - 3.0" orifice saddle
2
4.0"
69
Model 2 - 4.0" orifice saddle
2
5.0"
53
Model 2 - 5.0" orifice
3
5.0"
36
no
3
6.0"
25
no
3
8.0"
23
no
120 hrs
48 hrs
803 Roper Creek Drive
Greenville, SC 29615
www.SWFeeSaver.com

Fee Saver
Stormwater Services
Marlee Float Skimmer Size Selection Report
Date
Company
Engineer
Project Name
Project Location
Basin Description
Actual Provided Volume Analysis
Other 2
Other 3
March 5, 2019
Yarbrough, Williams & Houle
Vincent G. Keene PE
COURTYARDS ON LAWYERS ROAD
STALLINGS, NC
Sediment Basin # 2
Inputs
Calculations
Max. Time to Drain, hrs = 120
Calculated Pond Volume, ft3 = 40,420
Min. Time to Drain, hrs = 48
Pond Depth, ft = 2
Calculated Pond Volume, gal = 302,342
Pond Top Length, ft = 100
Pond Top Width, ft = 236
Pond Bottom Length, ft = 85
Pond Bottom Width, ft = 200
Minimum Average Flow Rate Allowable
Maximum Average Flow Rate Allowable
8,084 cfd to drain in
0.094 cfs
20,210 cfd to drain in
0.234 cfs
Marlee Float Selection Chart
Model #
Orifice
Draw down time (hrs)
Acceptable for basin
1
1.0"
675
no
1
1.5"
369
no
1
2.0"
216
no
1
2.5"
133
no
2
3.0"
65
Model 2 - 3.0" orifice saddle
2
4.0"
49
Model 2 - 4.0" orifice saddle
2
5.0"
37
no
3
5.0"
26
no
3
6.0"
18
no
3
8.0"
16
no
120 hrs
48 hrs
803 Roper Creek Drive
Greenville, SC 29615
www.SWFeeSaver.com

EROSION CONTROL
TEMPORARY DITCH
CALCULATIONS

a
W
N
O N N
N
W
aovv,v,
g
S
F-
v
to
N
rn
0
=
N
W
W
V
O N m
er+1
o
of o
.-
Q0
U)
6i
>> > F-
w w w Q
x w cl
U
z
1--I
W
�
a
0
�
�
�NN
1"I`y
•
W
a
Z
a'
vi
Q
fn
•
13
0�
ti
O
M�
W
-77
a)
cu
U
N
O
N
co
N O
U rn Ln
0
� Z
o ~ ,n
C) 0 4
J O
.af
O Q 0 x
a U w w
S
h-
a
W
0
a
a_
Z
O
N
J
m
Q
N
LL
0
W
n
2
a
Lli
Z z z z
r`
N
0
U
N O
v
W
N
W N V
M
M M M
Z
O
O O O
O
O O O
M
M M M
m
W
U
~
�
x
N N
Z
6.
N
u N M
W
O
� O
I I
�
W
w
_0
0
77—
M
N
A
�
N N
W
EL
OJ
v
N
d
O O
O a O
N
N
Cl) Cl)
o I I I-wItI'ILI0'
� NONi tr so V
w
Q Q Q N O O
sl I IOIOIOIOIO
1omiii��i1
x
U
Z
tl-H
0
0
o
20222Z>
LL
Z
f-

ENGINEERING.com I Open Channel Flow Calculator
Page 1 of 1
Other Calculators
Air Flow Conversion
Calculator
�►
Atmospheric Calculator
-0
Block Wall Calculator
Concrete Column
Calculator
Concrete Volume
-0
Calculator
Energy Conversion
-0
Calculator
Isentropic Flow Relations
Calculator
Laser Real Time Unit
r
Converter
Normal Flow Relations
Calculator
Oblique Flow Relations
-4
Calculator
Open -channel Flow
Calculator
Properties of Welds
-►
Treated as Lines
Calculator
Shaft Speed Calculator
Torque Transmitted by
.+
Clutch Calculator
Water Pump Engineering
Back to
ENGINEERING.com
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
9
Width (ft):
Enter the Channel Bottom
Width
��
I3 I
Enter the Channel
(' I
(ft):
Height (ft):
Enter the Flow Depth (ft):
[72-7--7
Enter the n value:
_03
Results
The wetted perimeter is 4.707E ft The flow is 2.8834� ft3/s
The flow area is 1.0287 ftZ The flow is 11294.112 gal/min
The hydraulic radius is 0.218E ft The velocity is 2.80304 ft/s
The C value is 38.546C
Calculate Reset i
https://www.engineering.com/calculators/open_channel_flow.htm 4/24/2019

ENGINEERING.com I Open Channel Flow Calculator Page 1 of 1
DIVERSION DITCH #2
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
Required Information
Concrete Column
Calculator
Enter the Slope: .0309
Enter the Channel Top 43
Width (ft):
�
Concrete Volume
Calculator
Enter the Channel Bottom 3
Width
Enter the Channel
(ft):
Height (ft):
.4
Energy Conversion Calculator
Enter the Flow Depth (ft):
11.58
Enter the n value: .03
y
Isentropic Flow Relations
Calculator
Res u Its
The wetted perimeter is 11.50E ft
The flow is C2.9188J ft'/s
Laser Real Time Unit
The flow area is 10.981 ftZ
The flow is 41701.61_ gal/min
Converter
0
The hydraulic radius is .9541 ft
The velocity is 18.46171 ft/s
Normal Flow Relations
Calculator
The C value is 49.279�
Oblique Flow Relations
L.Calculate
Reset
Calculator
y
Open -channel Flow
Calculator
Properties of Welds
-�
Treated as Lines
Calculator
Shaft Speed Calculator
Torque Transmitted by
Clutch Calculator
-0
Water Pump Engineering
Back to
ENGINEERING.com
https://www.engineering.com/calculators/open_channel_flow.htm 4/24/2019

ENGINEERING.com I Open Channel Flow Calculator
Page I of I
Other Calculators
Air Flow Conversion
Calculator
-k
Atmospheric Calculator
-►
Block Wall Calculator
Concrete Column
y
Calculator
Concrete Volume
Calculator
Energy Conversion
Calculator
-0
Isentropic Flow Relations
Calculator
Laser Real Time Unit
Converter
Normal Flow Relations
Calculator
Oblique Flow Relations
Calculator
Open -channel Flow
Calculator
Properties of Welds
-►
Treated as Lines
Calculator
�►
Shaft Speed Calculator
Torque Transmitted by
Clutch Calculator
.►
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 40
Width (ft):
Enter the Channel Bottom Enter the Channel
Width (ft): l�Height (ft):
Enter the Flow Depth (ft):295� Enter the n value: 03
Results
The wetted perimeter is 10.31 8 ft The flow is 43.671 i ft3/s
The flow area is 8.3171 ftZ The flow is 19599.871 gallmin
The hydraulic radius is 0.806C ft The velocity is 5.25081 ft/s
The C value is 47.913�
Calculate Reset
https://www.engineering.com/calculators/open_channel_flow.htm 4/24/2019

ENGINEERING.com I Open Channel Flow Calculator
Page I of 1
Other Calculators
Air Flow Conversion
Calculator
-+
Atmospheric Calculator
�►
Block Wall Calculator
Concrete Column
Calculator
Concrete Volume
Calculator
Energy Conversion
Calculator
Isentropic Flow Relations
Calculator
Laser Real Time Unit
y
Converter
Normal Flow Relations
Calculator
Oblique Flow Relations
y
Calculator
Open -channel Flow
y
Calculator
Properties of Welds
-o
Treated as Lines
Calculator
Shaft Speed Calculator
Torque Transmitted by
Clutch Calculator
�►
Water Pump Engineering
Back to
ENGINEERING.com
DIVERSION DITCH #4
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:
F. 0361 1
Enter the Channel Top
Width
(� �
(ft):
Enter the Channel Bottom
Width
13j� I
Enter the Channel
(ft):
Height (ft):
(' I
Enter the Flow Depth (ft):
1.382 1
Enter the n value:
03
Results
The wetted perimeter is 5.415s ft The flow is 6.5844E ft3/s
The flow area is 1.5837 ftZ The flow is 2955.115' gal/min
The hydraulic radius is 0.2924 ft The velocity is 4.1574E ft/s
The C value is 40.463E
Calculate Reset
https://www.engineering.com/calculators/open_channel_flow.htm 4/24/2019

ENGINEERING.com I Open Channel Flow Calculator
Page I of I
Other Calculators
Air Flow Conversion
Calculator
—b
Atmospheric Calculator
�►
Block Wall Calculator
Concrete Column
Calculator
Concrete Volume
rt
Calculator
Energy Conversion
Calculator
Isentropic Flow Relations
Calculator
Laser Real Time Unit
Converter
Normal Flow Relations
Calculator
Oblique Flow Relations
y
Calculator
Open -channel Flow
Calculator
Properties of Welds
-�
Treated as Lines
Calculator
�►
Shaft Speed Calculator
Torque Transmitted by
Clutch Calculator
�+
Water Pump Engineering
Back to
ENGINEERING.com
DIVERSION DITCH #5
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:
0177
Enter the Channel Top
15
Width (ft):
Enter the Channel Bottom
Width
(�
Enter the Channel
12
�
(ft):
13
Height (ft):
Enter the Flow Depth (ft):
1.24
Enter the n value:
03
Results
The wetted perimeter is F0.842 ft The flow is 46.1974 ft3/s
The flow area is 8.3327 ft2 The flow is 20733^43 gal/min
The hydraulic radius is 0.768� ft The velocity is 5.5440E ft/s
The C value is 47.534E
Calculate Reset
https://www.engineering.com/calculators/open_channel_flow.htm 4/24/2019

DETENTION SUMMARY

-a
O
Il cn
p M
�
1 rl
�
o1Do 0
r-1 r-i
k
M
M
oo
N
Q1 c�I
d 00
LLQ lD
a❑
N
N 1-1
N N
M N
Ln u
`�
.4
000 m
1n �
m CC
m
'--I
OO Ln
Ln N wm
M N
d• N
I�
m
Ln
N
O
m 00
�: O
lO �
0000 Ln
Lq Ln
kD
N 00
O M
M r1
tk
Q
m
❑
00
d
rn
w
wW
N
M
I� O
M Ln
N�
M
rl Ln
M N
� rl
rl N
fD
� M
.4
O
O
N O
N O
LO O
lO O
O1 O
00 O
N O
0 O
f0
�
u
LA
�
LDD O
m 0000
d' w
O1 rN-I
i
of
m
r i ri
oo cri
-I
Ln Ln
4J
f�
J
t/1
>
O
U
U
C
Gai
N
z
_O
~
z
LU
Q
W
f6
C
❑
v
v
f0
CU
000
•�
m
❑
+
vi
0
N N
W
LU ❑
❑
LU N
d O
a
cr >-
0-4
> LU
LU ❑
0 F—
LL
cr Ln
a 0
a
cr- >-
Ln N
N
> LU
LU ❑
4 F-
LL
cr Ln
o O
o
O O
i
> Lu
Lu Cl
❑
N
a 0
a
4J
•1
0
W
D_
O
^L
I..L
0

WET POND #1
CALCULATIONS

)LMI
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 : 4/26/2019 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 Grou
CN
(weighted) 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
CN,.,
65
Post - CN
Acres a
Land Use
Soil Type
H drolo is Grou
CN
wei hted CN
12.88
Bld / vt
98
39.79
3.48
Grass
B
61
6.69
7.26
Grass
C
74
16.94
8.10
Grass
D
80
20.43
31.72
Post CN_t 84
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
Step 3
for the 1-year, 24 hour storm.
Pre -development 1-year, 24 hr storm volume =
Post -development 1-year, 24 hr storm 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
t4 (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
Q1.Yexr
Q2.y,,,
Q10.Y­
Q25_,,,,
Q50.Y­
cfs
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.y_
cfs
19.18
10.12
Perm Pool Storage -Elevation Data
Elevation
Area (sf)
Area (so)
Ht (ft)
Inc. Vol (ac-ft)
Acc. Vol (ac-ft)
Acc. Vol (cf)
651.5
12000.0
0.275
-1.0
0.000
0.000
0
652.5
13000.0
0.298
0.0
0.000
0.000
0
654
15000.0
0.344
1.5
0.482
0.482
21000
656
18000.0 1
0.413
3.5
0.758
1.240
54000
658
21000.0
0.482
5.5
0.895
2.135
93000
660
24000.0
0.551
7.5
1.033
3.168
138000
660.5
29000.0
0.666
8.0
0.304
3.472
151250
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 =
29,000
sf
Shelf Area =
24,000
sf
Surface Area Bol Pond =
13,000
sf
Permanent Pool Volume =
151,250
cf
Avg. Depth = 6.2 ft
Using avg = 6.2 and 41 % impervious cover, Min. SA/DA Ratio From State Table 1) 10.9%
Surface area required = 12214 sf
Surface area provided = 29000 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 = 2.85 ac-ft X 43560 Oacre / (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 = 151250.00 cF x (020) _
30250 cf = 0.69 ac-ft
Proposed Forebay Chamber Volume 1 31500 cf
Forebay Chamber Storo e-Elevation Data
Elevation
Area sf
Area ac
Ht ft
Inc. Vol ac-ft
Acc. Vol ac-ft
Acc. Vol cf
652.5
1500.0
0.034
0.0
0.000
0.000
0.0
654
2200.0
0.051
1.5
0.064
0.064
2775.0
656
3400.0
0.076
3.5
0.129
0.192
8375.0
658
4800.0
0.110
5.5
0.188
0.381
16575.0
660
6400.0
0.147
7.5
0.257
0.638
27775.0
660.5
8500.0
0.195
8.0
0.086
0.723
31500.0
Step 7 Develop Water Quality Storage -Elevation Table
Permanent Pond Surface Elev.
Water Quality Storage -Elevation Data
Elevation
Area of
Area ac
Ht ft
Inc. Vol ac-ft
Acc. Vol ac-ft
Acc. Vol
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=
3500-0
sf - avg.
h =
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
sf
sf 7.5' x 7.5'
Top of Dam =
669.00
Top of Box =
667.75
Pond Shelf =
661.00
Bottom of Box =
659.30
Box Area =
25
Anchor Area =
56.25
Anchor thickness =
1
Area of Riser - Inside 16 sf / Outside 25 at
V (wetwell) = V (riser) + V(base footing) _ (667.75-659.3) X (25) + 1.0 X (56.25) = 268 cf
Floatation = V(wetwell) x V(water) = 267.5 cf x 62.4 Ib/cf = 16692 Ibs
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 Ibs
Earth Wt. = V(Earth) X Earth Unit Wt. _
(56.25-25) X 1.2X 115 LBS/CF = 4313 Ibs
Anti -Floatation = 24158 Ibs
C. Safety Factor = 1.4 1.1 required by NCDENR for Anti-floation
x 7.5'x

WET POND #1
HYDROCAD REPORT

is
PRE DRAINAGE AREA
#1
Subcat Reach on Link Routing Diagram for Wet Pond # 1
Prepared by Microsoft, Printed 5/6/2019
FHydroCADO 10.00-22 s/n 05047 0 2018 HydroCAD Software Solutions LLC

Wet Pond # 1 Charlotte 24-hr 1-yr 1 yr Rainfall=2.58"
Prepared by Microsoft Printed 5/6/2019
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
0 10 2 0 40 .0 o
Hydrograph
Charlotte 24-hr 1-yr
1 yr Rainfall=2.58"
Runoff Area=9.580 ac
Runoff Volume=0.262 of
Runoff Depth=0.33"
Flow Len6th=1,480'
Tc=28.2 m i n
CN=65
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 5/6/2019
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
V 1
3
0
LL
0-.
0 10 20 30 40 50 60 70
Hydrograph
Charlotte 6-hr
2-yr
2 yr Rainfall=2.28"
Runoff Area=9.580 ac
Runoff Volume=0.175 of
Runoff Depth=0.22"
Flow Length=1,480'
Tc=28.2 min
CN=65
80 90 100 110 120 130 140 150 160 170
Time (hours)
p Runoff

Wet Pond # 1 Charlotte 6-hr 10-yr 10 yr Rainfall=3.72"
Prepared by Microsoft Printed 5/6/2019
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
N
3
0
LL
Subcatchment 1S: PRE DRAINAGE AREA #1
Hydrograph
7
6
Charlotte 6-hr 10-yr
10 yr Rainfall=3.72"
Runoff Area=9.580 ac
Runoff Volume=0.695 of
Runoff Depth=0.87"
Flow Length=1,480'
Tc=28.2 m i n
CN=65
0-
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 5/6/2019
HydroCAD® 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
Subcatchment 1S: PRE DRAINAGE AREA #1
Hydrograph
13 12.48 cfs
12 Charlotte 6-hr
11 25-yr
10 25 yr Rainfall=4.38"
Runoff Area=9.580 ac
7 Runoff Volume=1.003 of
3
LL
6 Rupoff Depth=1.26"
5- Flow Length=1,480'
4 Tc=28.2 m i n
3 CN=65
0
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)
p Runoff

Wet Pond # 1 Charlotte 6-hr 50-yr 50 yr Rainfall=4.92"
Prepared by Microsoft Printed 5/6/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 6
Summary for Subcatchment 1S: 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
171
15.95 cfs
16: Charlotte 6-hr
15
14 50-yr
13
12= 50 yr Rainfall=4.92"
11 Runoff Area=9.580 ac
Flo.
9Runoff Volume=1.278 of
3 :
LL $= Runoff Depth=1.60"
Flow Length=1480'
5 Tc=28.2 m i n
4 CN=65
0
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 5/6/2019
HydroCADO 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
Hydrograph
21
® Runoff
19
Charlotte 6-hr
18,
100-yr
16_
15
100 yr Rainfall=5.34"
14'
13
Runoff Area=9.580 ac
12'
v 11
Runoff (Volume=1.504 of
iZ '9
Runoff Depth=1.88"
8-
Flow Length=1480'
7
6
Tc=28.2 m i n
5
4
CN=65
3-
2 -
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)

POST WP # 1
Subcat Reach on Link
Wet Pond # 1

Wet Pond # 1 Charlotte 24-hr 1-yr 1 yr Rainfall=2.58"
Prepared by Microsoft Printed 5/7/2019
HydroCAD@) 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 2
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
50
46
44
w 28
26
0 24
LL 22
20
18
16
14
12
10
4
963 Total
Subcatchment 4S: POST WP # 1
Hydrograph
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
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 24-hr 1-yr 1 yr Rainfall=2.58"
Prepared by Microsoft Printed 5/7/2019
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 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=1.02 cfs @ 19.02 hrs HW=663.13' (Free Discharge)
L1=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 5/7/2019
HydroCADO 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 5/7/2019
HydroCAD® 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
55
u 30.
.2 25
20
15
10
5
963 Total
Subcatchment 4S: POST WP # 1
Hydrograph
Time (hours)
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
i
p Runoff

Wet Pond # 1 Charlotte 6-hr 2-yr 2 yr Rainfall=2.28"
Prepared by Microsoft Printed 5/7/2019
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'/' 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 5/7/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 7
Pond 33P: Wet Pond # 1
Hydrograph
■ Inflow
I El 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 5/7/2019
HydroCAD® 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
11
11
10
10
w 65
60
0 55
u- 50
45
40
35
30
25
20
15
10
5
963 Total
Subcatchment 4S: POST WP # 1
Hydrograph
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)
Runoff

Wet Pond # 1 Charlotte 6-hr 10-yr 10 yr Rainfall=3.72"
Prepared by Microsoft Printed 5/7/2019
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 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=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 5/7/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 10
w
u
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
0 Primary

Wet Pond # 1 Charlotte 6-hr 25-yr 25 yr Rainfall=4.38"
Prepared by Microsoft Printed 5/7/2019
HydroCAD® 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 cfs
13° Charlotte 6-hr
120
110 25-yr
100_ 25 yr Rainfall=4.38"
s° Runoff Area=31.720 ac
80 Runoff Volume=7.160 of
'°
- 60 Runoff Depth=2.71"
�.
50 Flow Length=963'
40_ Tc=14.2 min
3°- CN=84
® Runoff

Wet Pond # 1 Charlotte 6-hr 25-yr 25 yr Rainfall=4.38"
Prepared by Microsoft Printed 5/7/2019
HydroCADO 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)
L1=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 5/7/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 13
a
3
0
U.
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 5/7/2019
HydroCAD® 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
14.2 963 Total
Subcatchment 4S: POST WP # 1
Hydrograph
16
150.50 cfs
150 Charlotte 6-hr
140
130 50-yr
120 50 yr Rainfall=4.92"
110 Runoff Area=31.720 ac
100
Runoff Volume=8.452 of
80 Runoff Depth=3.20"
6° Flow Length=963'
5 Tc=14.2 min
40
30- CN=84
20
10
0-
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 5/7/2019
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 Routina 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 5/7/2019
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 5/7/2019
HydroCADO 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
0 90
LL on
963 Total
Subcatchment 4S: POST WP # 1
Hydrograph
Runoff
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=14.2 min
40.1 E 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 100-yr 100 yr Rainfall=5.34"
Prepared by Microsoft Printed 5/7/2019
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 5/7/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 19
1
1
1
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)
IN Inflow
p Primary

WET POND #2
CALCULATIONS

ywi
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 - 5g
Soils Types: Cecil Enon
Zoning: Residential
Hydrologic Data
Pre - CN
Land Use
Soil T e
H drolo is Groug
CN
wei hted 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
CN.,,
75
Post - CN
Acrea a
Land Use
Soil Type
Hydrologic Group
CN
(weighted) CN
8.4
Bid / 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 CNp_ 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 storm volume =
DIFFERENCE IN 1 YEAR STORM VOLUME _
AT ELEV. 665.28 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 B
79366.32
43,037 cf required for treatment
44,997 cf RELEASED GRADUALLY DURING 120 HOURS
WITH A PEAK RATE OF Approx. 0.39 afs
Condition
Area
CN
t. (hours)
t. (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, y,,,
Q2. ,,,
Q10"
Q25.r,,,
Q50,
cfs
cfs
cis
cfs
cis
Pre -development Flow
7,45
7.48
21.90
29.47
35.54
Post Development Detained
0.93
1.25
17.14
22,84
26.61
The facility would require 0.99 ac-ft for
Water Quality Volume (WQv) treatment
Perm Pool Storage
-Elevation Data
Elevation
Area (sf)
Area (ac)
Ht (ft)
Inc. Vol (ac-ft)
Ace. Vol (ac-ft)
Acc. Vol (cf)
651
1000
0.023
-1.0
0.000
0.000
0
652
1300.0
0.030
0.0
0,000
0,000
0
654
2000.0
0.046
2.0
0.076
0.076
3300
656
2900.0
0.067
4.0
0.112
0.188
8200
658
3900.0
0.090
6.0
0.156
0.344
15000
660
5000.0
0.115
8.0
0.204
0.549
23900
662
6300.0
0.145
10.0
0.259
0.808
35200
662.5
8000.0
0.184 1
10.5 1
0.082
1 0.890
38775
Permanent Pool Volume
Depth =
10.50
it
PPE Elevation =
662.5
Shelf Elevation =
662
Bottom Elevation =
651
Bottom Elevation +1 =
652
PPE Surface Area =
8,000
sf
Shelf Area = 1
6,300
sf
Surface Area Bot Pond =
1,300
sf
Permanent Pool Volume =
38,775
cf
Avg. Depth = 6A ft
Using avg = 6.1 and 59% impervious cover, Min. SA/DA Ratio
Surface area required = 7505 sf
Surface area provided = 8000 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 fe/acre / (51 hrs X 3600 sec/hr)
= 0.234 cis

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 = 38775.00 cf x (0.20) _
= 7755 cf = 0.18 ac-ft
Proposed Forebay, Chamber Volume= 1 9665 7cf
Forebay Chamber Store e-Elevation Data
Elevation
Areas
Area ac
Ht ft
Inc. Vol ac-ft
Acc. Vol ac-ft
Acc. Vol cf
652
90.0
0.002
0.0
0.000
0.000
0.0
654
300.0
0.007
2.0
0.009
0.009
390.0
656
600.0
0.014
4.0
0.021
0.030
1290.0
658
900.0
0.021
6.0
0.034
0.064
2790.0
660
1400.0
0.032
8.0
0.053
1 0.117
5090.0
662
2000.0
0.046
10.0
0.078
0.195
8490.0
662.5
2700.0
0.062
10.5
0.027
0.222
9665.0
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
8000.0
0.184
0.0
0.000
0.0
663
10000.0
0.230
0.5
0.103
0.103
4500.0
665
12500.0
0.287
2.5
0.517
0.620
27000.0
667
15400.0
0.354
4.5
0.640
1.260
54900.0
669
18500.0
0.425
6.5
0.778
2.039
88800.0
671
21900.0
0.503
8.5
0.927
2.966
129200.0
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=
10250.0
sf - avg.
hr_
2.50
C=
0.6
g=
32.2
t =
172800 sec = 48 hrs
a =
0.03896
Dia =
3 in

Step 10 Calculation for Anti -flotation Concrete Anchor
A. Bouyancy
Elevation
Top of Dam =
671.00
Top of Box =
669.49
Pond Shelf =
662.00
Bottom of Box =
660.91
Box Area =
25
sf
Anchor Area =
49
sf Tx 7'
Anchorthickne:: =
1
Area of Riser - Inside 16 sf / Outside 25 sf
V (wetwell) = V (riser) + V(base footing) _ (669.49 - 660.91) X 25 + (1.0 X 49) = 264
Floatation = V(wetwell) x V(water) = 263.5 cf x 62.4 Ib/cf = 16442
B. Counter Bouyancy
Conc. Wt. _ {V(conc. riser) + V(conc. Footing)) x Conc. Unit Wt. _
{(25-16) x (669.49-660.91)+ (49 x 1)) x 150 Ibs/cf = 18933
Earth Wt. = V(Earth) X Earth Unit Wt. _
(49-25) X 1.59 X 115 LBS/CF = 4388
Anti -Floatation = 23321 Ibs
C. Safety Factor= 1.4 1.1 required by NCDENR forAnti-floation

WET POND #2
HYDROCAD REPORT

PRE DRAINAGE AREA
Subcat Reach on Link

Wet Pond #2 Charlotte 24-hr 1-yr 1 yrRainfall=2.58"
Prepared by Microsoft Printed 5/7/2019
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 1 S: PRE DRAINAGE AREA
Hydrograph
8
7.45 cfs
7- Charlotte 24-hr 1-yr
1 yr Rainfall=2.58"
Runoff Area=14.340 ac
5 Runoff Volume=0.834 of
Runoff Depth=0.70"
LL 4 Flow Length=1175'
3 Tc=30.5 m i n
CN=75
2
1
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)
p Runoff

Wet Pond #2 Charlotte 6-hr 2-yr 2 yr Rainfall=2.28"
Prepared by Microsoft Printed 5/7/2019
HydroCAD® 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
p Runoff
7-
Charlotte 6-hr
2-yr
6 2 yr Rainfall=2.28"
5 Runoff Area=14.340 ac
Runoff Volume=0.629 of
4- 'Runoff Depth=0.53"
3 Flow Length=1,175'
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 Charlotte 6-hr 10-yr 10 yr Rainfall=3.72"
Prepared by Microsoft Printed 5/7/2019
HydroCADO 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
p Runoff
22
21= Charlotte 6-,hr 10-yr
19 10 yr Rainfall=3.72"
18`
17_ Runoff Area=14.340 ac
16 Runoff Volume=1.744 of
14 13: Runoff Depth=1.46"
0 12 Flow Length=1175'
0 11
10:
9 Tc=30.5 m i n
8:
7 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 Charlotte 6-hr 25-yr 25 yr Rainfall=4.38"
Prepared by Microsoft Printed 5/7/2019
HydroCADO 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
p Runoff
28 Charlotte 6-hr
26 _ 25-yr
24 25 yr Rai'nfall=4.38"
22_
20_ Runoff Area=14.340 ac
18 Runoff Volume=2.338 of
,4 Runoff Depth=1.96"
12 Flow Length=1175'
10- Tc=30.5 m i n
8
6 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 Charlotte 6-hr 50-yr 50 yr Rainfall=4.92"
Prepared by Microsoft Printed 5/7/2019
HydroCADO 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 1,175 Total
Subcatchment 1S: PRE DRAINAGE AREA
34-
32-
30
28-
24
22
a 20-
.—o° 18-
16
- 6 10 20 30 • 0 50 60 70
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
80 90 100 110 120 130 140 150 160 170
Time (hours)
® Runoff

Wet Pond #2 Charlotte 6-hr 100-yr 100 yr Rainfall=5.34"
Prepared by Microsoft Printed 5/7/2019
HydroCAD® 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 1S: PRE DRAINAGE AREA
Hydrograph
p Runoff
40
Charlotte r
38
36;
/�6-h
100-yr
34°
32:
100 yr Rainfall=5.34"
28
Runoff Area=14.340 ac
26°
24
Runoff Volume=3.260 of
22
20
Runoff Depth=2.73"
16
Flow Length=1,175'
14
12
Tc=30.5 m i n
10'
CN=75
6
6
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)

POST WP #2
Subcat Reach on Link
Wet Pond # 2

Wet Pond #2 Charlotte 24-hr 1-yr 1 yr Rainfall=2.58"
Prepared by Microsoft Printed 5/7/2019
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
Subcatchment 4S: POST WP #2
Hydrograph
23_
22' 2126 cts
21 Charlotte 24-hr 1-yr
20'
19' 1 yr Rainfall=2.58"
18
17' Runoff Area=14.340 ac
16-
15 Runoff Volume=1.822 of
14 oz
13_
12Ru'noRunoffDepth=1.52"
3 °
10 Flow Length=430'
Tc=23.4 m i n
8'
7-
1: CN=89
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)
Runoff

Wet Pond #2 Charlotte 24-hr 1-yr 1 yrRainfall=2.58"
Prepared by Microsoft Printed 5/7/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 3
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 = 0.93 cfs @ 15.52 hrs, Volume= 1.822 af, Atten= 96%, Lag= 197.7 min
Primary = 0.93 cfs @ 15.52 hrs, Volume= 1.822 of
Routing by Stor-Ind method, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs / 3
Peak Elev= 666.79' @ 15.52 hrs Surf.Area= 15,090 sf Storage= 51,654 cf
Plug -Flow detention time= 952.1 min calculated for 1.822 of (100% of inflow)
Center -of -Mass det. time= 952.5 min ( 1,787.9 - 835.5 )
Volume Invert Avail.Storage Storage Description
#1 662.50' 128,950 cf Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic -feet) (cubic -feet)
662.50 8,000 0 0
663.00 10,000 4,500 4,500
664.00 11,200 10,600 15,100
665.00 12,500 11,850 26,950
666.00 13,900 13,200 40,150
667.00 15,400 14,650 54,800
668.00 16,900 16,150 70,950
669.00 18,500 17,700 88,650
670.00 20,100 19,300 107,950
671.00 21,900 21,000 128,950
Device Routing Invert Outlet Devices
#1 Primary 660.91' 24.0" Round Culvert L= 82.1' Ke= 0.500
Inlet / Outlet Invert= 660.91' / 660.50' S= 0.0050'/' 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 1 669.49' 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' 4.0" Vert. Orifice/Grate C= 0.600
#5 Device 1 666.90' 13.0" Vert. Orifice/Grate X 4.00 C= 0.600
Primary OutFlow Max=0.93 cfs @ 15.52 hrs HW=666.79' (Free Discharge)
L1=Culvert (Passes 0.93 cfs of 33.43 cfs potential flow)
2=Orifice/Grate (Orifice Controls 0.48 cfs @ 9.83 fps)
3=Broad-Crested Rectangular Weir ( Controls 0.00 cfs)
=Orifice/Grate (Orifice Controls 0.45 cfs @ 5.11 fps)
=Orifice/Grate ( Controls 0.00 cfs)

Wet Pond #2 Charlotte 24-hr 1-yr 1 yr Rainfall=2.58"
Prepared by Microsoft Printed 5/7/2019
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 Charlotte 6-hr 2-yr 2 yr Rainfall=2.28"
Prepared by Microsoft Printed 5/7/2019
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
0 Runoff
23 Charlotte 6-hr
22
21
20 2-yr
8 2 yr Rai'nfall=2.28"
17
16,Runoff Area=14.340 ac
15 14 Runoff Volume=1.511 of
3 13
12 Runoff Depth=1.26"
'9 Flow Length=430'
7 Tc=23.4 m i n
7
6.
5° CN=89
4-
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)

Wet Pond #2 Charlotte 6-hr 2-yr 2 yr Rainfall=2.28"
Prepared by Microsoft Printed 5/7/2019
HydroCADO 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 =
1.25 cfs @
5.83 hrs, Volume=
1.511 af, Atten= 95%, Lag= 146.0 min
Primary =
1.25 cfs @
5.83 hrs, Volume=
1.511 of
Routing by Stor-Ind method, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs / 3
Peak Elev= 667.02' @ 5.83 hrs Surf.Area= 15,426 sf Storage= 55,069 cf
Plug -Flow detention time= 943.1 min calculated for 1.511 of (100% of inflow)
Center -of -Mass det. time= 943.5 min ( 1,173.3 - 229.8 )
Volume Invert
Avail.Storage Storage Description
#1 662.50'
128,950 cf Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation Surf.Area
Inc.Store Cum.Store
(feet)
(sq-ft)
(cubic -feet) (cubic -feet)
662.50
8,000
0 0
663.00
10,000
4,500 4,500
664.00
11,200
10,600 15,100
665.00
12,500
11,850 26,950
666.00
13,900
13,200 40,150
667.00
15,400
14,650 54,800
668.00
16,900
16,150 70,950
669.00
18,500
17,700 88,650
670.00
20,100
19,300 107,950
671.00
21,900
21,000 128,950
Device Routing
Invert
Outlet Devices
#1 Primary
660.91'
24.0" Round Culvert L= 82.1' Ke= 0.500
Inlet / Outlet Invert= 660.91' / 660.50' S= 0.0050 '/' 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
669.49'
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'
4.0" Vert. Orifice/Grate C= 0.600
#5 Device 1
666.90'
13.0" Vert. Orifice/Grate X 4.00 C= 0.600
Primary OutFlow Max=1.24 cfs @ 5.83 hrs HW=667.02' (Free Discharge)
L1=Culvert (Passes 1.24 cfs of 34.19 cfs potential flow)
2=Orifice/Grate (Orifice Controls 0.50 cfs @ 10.09 fps)
3=Broad-Crested Rectangular Weir ( Controls 0.00 cfs)
=Orifice/Grate (Orifice Controls 0.49 cfs @ 5.60 fps)
=Orifice/Grate (Orifice Controls 0.25 cfs @ 1.17 fps)

Wet Pond #2 Charlotte 6-hr 2-yr 2 yr Rainfall=2.28"
Prepared by Microsoft Printed 5/7/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 7
w
u
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

Wet Pond #2 Charlotte 6-hr 10-yr 10 yr Rainfall=3.72"
Prepared by Microsoft Printed 5/7/2019
HydroCADO 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
Subcatchment 4S: POST WP #2
34
32
_ 30
y 28
—� 26
0 24
LL 22
12-
10
8-
6
4
2
0 10 20 30 40 50 60 70
Hydrograph
Charlotte 6-hr 10-yr
10 yr Rainfall=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
CN=89
80 90 100 110 120 130 140 150 160 170
Time (hours)
m Runoff

Wet Pond #2 Charlotte 6-hr 10-yr 10 yr Rainfall=3.72"
Prepared by Microsoft Printed 5/7/2019
HydroCAD® 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 = 17.14 cfs @ 3.80 hrs, Volume= 3.061 af, Atten= 62%, Lag= 24.9 min
Primary = 17.14 cfs @ 3.80 hrs, Volume= 3.061 of
Routing by Stor-Ind method, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs / 3
Peak Elev= 668.24' @ 3.80 hrs Surf.Area= 17,291 sf Storage= 75,130 cf
Plug -Flow detention time= 496.2 min calculated for 3.061 of (100% of inflow)
Center -of -Mass det. time= 496.6 min ( 721.0 - 224.4 )
Volume
Invert Avail.Storage
Storage
Description
#1
662.50' 128,950 cf
Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation
Surf.Area Inc.Store
Cum.Store
(feet)
(sq-ft) (cubic -feet)
(cubic -feet)
662.50
8,000
0
0
663.00
10,000
4,500
4,500
664.00
11,200
10,600
15,100
665.00
12,500
11,850
26,950
666.00
13,900
13,200
40,150
667.00
15,400
14,650
54,800
668.00
16,900
16,150
70,950
669.00
18,500
17,700
88,650
670.00
20,100
19,300
107,950
671.00
21,900
21,000
128,950
Device Routing Invert Outlet Devices
#1
Primary
660.91'
24.0" Round Culvert L= 82.1' Ke= 0.500
Inlet / Outlet Invert= 660.91' / 660.50' S= 0.0050 '/' 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
669.49'
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'
4.0" Vert. Orifice/Grate C= 0.600
#5
Device 1
666.90'
13.0" Vert. Orifice/Grate X 4.00 C= 0.600
Primary OutFlow Max=17.14 cfs @ 3.80 hrs HW=668.24' (Free Discharge)
L1=Culvert (Passes 17.14 cfs of 38.07 cfs potential flow)
2=Orifice/Grate (Orifice Controls 0.56 cfs @ 11.41 fps)
3=Broad-Crested Rectangular Weir ( Controls 0.00 cfs)
4=Orifice/Grate (Orifice Controls 0.67 cfs @ 7.73 fps)
=Orifice/Grate (Orifice Controls 15.91 cfs @ 4.31 fps)

Wet Pond #2 Charlotte 6-hr 10-yr 10 yr Rainfall=3.72"
Prepared by Microsoft Printed 5/7/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 10
Pond 33P: Wet Pond # 2
Hydrograph
■ Inflow
p Primary
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)

Wet Pond #2 Charlotte 6-hr 25-yr 25 yr Rainfall=4.38"
Prepared by Microsoft Printed 5/7/2019
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
w 35
30
0
LL 25
20
15
10
Subcatchment 4S: POST WP #2
0 10 20 30 40 50 60 70
Hydrograph
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 m i n
CN=89
80 90 100 110 120 130 140 150 160 170
Time (hours)
p Runoff

Wet Pond #2 Charlotte 6-hr 25-yr 25 yr Rainfall=4.38"
Prepared by Microsoft Printed 5/7/2019
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 =
22.84 cfs @
3.72 hrs, Volume= 3.802 af, Atten= 58%, Lag= 22.4 min
Primary =
22.84 cfs @
3.72 hrs, Volume= 3.802 of
Routing by Stor-Ind method, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs / 3
Peak Elev= 668.91'
@ 3.72 hrs
Surf.Area= 18,351 sf Storage= 86,934 cf
Plug -Flow detention time= 408.1
min calculated for 3.802 of (100% of inflow)
Center -of -Mass det. time= 408.5
min ( 629.3 - 220.8 )
Volume Invert Avail.Storage Storage Description
#1 662.50' 128,950 cf Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation
Surf.Area
Inc.Store Cum.Store
(feet)
(sq-ft)
(cubic -feet) (cubic -feet)
662.50
8,000
0 0
663.00
10,000
4,500 4,500
664.00
11,200
10,600 15,100
665.00
12,500
11,850 26,950
666.00
13,900
13,200 40,150
667.00
15,400
14,650 54,800
668.00
16,900
16,150 70,950
669.00
18,500
17,700 88,650
670.00
20,100
19,300 107,950
671.00
21,900
21,000 128,950
Device Routing
Invert
Outlet Devices
#1 Primary
660.91'
24.0" Round Culvert L= 82.1' Ke= 0.500
Inlet / Outlet Invert= 660.91' / 660.50' S= 0.0050'/' 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
669.49'
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'
4.0" Vert. Orifice/Grate C= 0.600
#5 Device 1
666.90'
13.0" Vert. Orifice/Grate X 4.00 C= 0.600
Primary OutFlow Max=22.84 cfs @ 3.72 hrs HW=668.91' (Free Discharge)
L1=Culvert (Passes 22.84 cfs of 40.01 cfs potential flow)
2=Orifice/Grate (Orifice Controls 0.59 cfs @ 12.07 fps)
3=Broad-Crested Rectangular Weir ( Controls 0.00 cfs)
=Orifice/Grate (Orifice Controls 0.76 cfs @ 8.67 fps)
=Orifice/Grate (Orifice Controls 21.49 cfs @ 5.83 fps)

Wet Pond #2 Charlotte 6-hr 25-yr 25 yr Rainfall=4.38"
Prepared by Microsoft Printed 5/7/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 13
Pond 33P: Wet Pond # 2
Hydrograph
■ Inflow
p Primary
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)

Wet Pond #2 Charlotte 6-hr 50-yr 50 yr Rainfall=4.92"
Prepared by Microsoft Printed 5/7/2019
HydroCADO 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
60
55
50
45
a 40
3 35
0
LL 30
25
20
15
10-
Subcatchment 4S: POST WP #2
1 10 20 30 40 50 .0 74
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 Charlotte 6-hr 50-yr 50 yr Rainfall=4.92"
Prepared by Microsoft Printed 5/7/2019
HydroCADO 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 =
26.61 cfs @
3.71 hrs, Volume=
4.416 af, Atten= 57%, Lag= 21.8 min
Primary =
26.61 cfs @
3.71 hrs, Volume=
4.416 of
Routing by Stor-Ind method, Time
Span= 0.00-179.00
hrs, dt= 0.01 hrs / 3
Peak Elev= 669.45' @ 3.71 hrs
Surf.Area= 19,225 sf
Storage= 97,203 cf
Plug -Flow detention
time= 357.6
min calculated for 4.416 of (100% of inflow)
Center -of -Mass det.
time= 358.0
min ( 578.0 - 220.0 )
Volume Invert Avail.Storage Storage Description
#1 662.50' 128,950 cf Custom Stage
Data (Prismatic) Listed below (Recalc)
Elevation
Surf.Area
Inc.Store Cum.Store
(feet)
(sq-ft)
(cubic -feet) (cubic -feet)
662.50
8,000
0
0
663.00
10,000
4,500
4,500
664.00
11,200
10,600
15,100
665.00
12,500
11,850
26,950
666.00
13,900
13,200
40,150
667.00
15,400
14,650
54,800
668.00
16,900
16,150
70,950
669.00
18,500
17,700
88,650
670.00
20,100
19,300
107,950
671.00
21,900
21,000
128,950
Device Routinq
Invert
Outlet Devices
#1
Primary
660.91'
24.0" Round Culvert L= 82.1' Ke= 0.500
Inlet / Outlet Invert= 660.91' / 660.50' S= 0.0050 '/' 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
669.49'
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'
4.0" Vert. Orifice/Grate C= 0.600
#5
Device 1
666.90'
13.0" Vert. Orifice/Grate X 4.00 C= 0.600
Primary OutFlow Max=26.62 cfs @ 3.71 hrs HW=669.45' (Free Discharge)
L1=Culvert (Passes 26.62 cfs of 41.55 cfs potential flow)
2=Orifice/Grate (Orifice Controls 0.62 cfs @ 12.58 fps)
3=Broad-Crested Rectangular Weir ( Controls 0.00 cfs)
=Orifice/Grate (Orifice Controls 0.82 cfs @ 9.37 fps)
5=Orifice/Grate (Orifice Controls 25.18 cfs @ 6.83 fps)

Wet Pond #2 Charlotte 6-hr 50-yr 50 yr Rainfall=4.92"
Prepared by Microsoft Printed 5/7/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 16
N
V
O
LL
Pond 33P: Wet Pond # 2
Hydrograph
0 1U 10 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)
■ Inflow
Primary

Wet Pond #2 Charlotte 6-hr 100-yr 100 yr Rainfall=5.34"
Prepared by Microsoft Printed 5/7/2019
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
N
3
0
U.
Subcatchment 4S: POST WP #2
65-
60
55
50-
25
20-
15-
0 10 20 30 40 50 60 70
Hydrograph
Charlotte 6-hr
100-yr
100 yr Rainfall=5.34"
Runoff Area=14.340 ac
Runoff Volume=4.897 of
Runoff Depth=4.10"
Flow Length=430'
Tc=23.4 min
CN=89
80 90 100 110 120 130 140 150 160 170
Time (hours)
� Runoff

Wet Pond #2 Charlotte 6-hr 100-yr 100 yr Rainfall=5.34"
Prepared by Microsoft Printed 5/7/2019
HydroCAD® 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 = 36.04 cfs @ 3.64 hrs, Volume= 4.897 af, Atten= 48%, Lag= 17.5 min
Primary = 36.04 cfs @ 3.64 hrs, Volume= 4.897 of
Routing by Stor-Ind method, Time Span= 0.00-179.00 hrs, dt= 0.01 hrs / 3
Peak Elev= 669.78' @ 3.64 hrs Surf.Area= 19,756 sf Storage= 103,662 cf
Plug -Flow detention time= 326.3 min calculated for 4.897 of (100% of inflow)
Center -of -Mass det. time= 326.2 min ( 545.5 - 219.3 )
Volume
Invert Avail.Storage
Storage
Description
#1
662.50' 128,950 cf
Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation
Surf.Area Inc.Store
Cum.Store
(feet)
(sq-ft) (cubic -feet)
(cubic -feet)
662.50
8,000
0
0
663.00
10,000
4,500
4,500
664.00
11,200
10,600
15,100
665.00
12,500
11,850
26,950
666.00
13,900
13,200
40,150
667.00
15,400
14,650
54,800
668.00
16,900
16,150
70,950
669.00
18,500
17,700
88,650
670.00
20,100
19,300
107,950
671.00
21,900
21,000
128,950
Device Routing Invert Outlet Devices
#1
Primary
660.91'
24.0" Round Culvert L= 82.1' Ke= 0.500
Inlet / Outlet Invert= 660.91' / 660.50' S= 0.0050 '/' 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
669.49'
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'
4.0" Vert. Orifice/Grate C= 0.600
#5
Device 1
666.90'
13.0" Vert. Orifice/Grate X 4.00 C= 0.600
Primary OutFlow Max=35.97 cfs @ 3.64 hrs HW=669.78' (Free Discharge)
L1=Culvert (Passes 35.97 cfs of 42.45 cfs potential flow)
2=Orifice/Grate (Orifice Controls 0.63 cfs @ 12.88 fps)
3=Broad-Crested Rectangular Weir (Weir Controls 7.31 cfs @ 1.55 fps)
=Orifice/Grate (Orifice Controls 0.85 cfs @ 9.77 fps)
=Orifice/Grate (Orifice Controls 27.17 cfs @ 7.37 fps)

Wet Pond #2 Charlotte 6-hr 100-yr 100 yr Rainfall=5.34"
Prepared by Microsoft Printed 5/7/2019
HydroCADO 10.00-22 s/n 05047 © 2018 HydroCAD Software Solutions LLC Page 19
Pond 33P: Wet Pond # 2
Hydrograph
F1 Inflow
❑ Primary
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170
Time (hours)