SW6220702_Design Calculations_20221102 (2)

CALCULATIONS
sheet only set up to handle Tc from 5 min to 30 min
A. Flow velocity < 2.0 fps when discharging to wetlands B. Flow velocity < 4.5 fps all other cases" C. Channel slope < 5.0% for curb outlet swales
Storm Event
Rainfall Intensity
5-min
10-min
15-min
30-min
10-yr
7.88
6.31
5.32
3.85
25-yr
8.78
7.00
5.92
4.38
50-yr
9.44
7.52
6.35
4.78
100-yr
1 10.101
8.00
6.74
5.16
Drainage
Impervious
Grassed
Tc
Storm
Rainfall
Ditch No.
C
Kerby
Kirpich
Intensity
Q (cfs)
Area (ac)
Area (ac)
Area (ac)
Event (yr)
Total Tc
Tc Used
(in/hr)
L (ft) n s
Tv
L (ft)
S
Tab
1
0.15
0.03
0.12
0.45
n/a
220.0
0.005
3.82
3.82
5
10-yr
7.88
0.53
2
0.09
0.01
0.08
0.40
n/a
125.0
0.005
2.47
2.47
5
10-yr
7.88
0.28
3
0.23
0.05
0.18
0.45
n/a
315.0
0.040
2.26
2.26
5
10-yr
7.88
0.82
4
1.52
0.12
1.40
0.35
n/a
515.0
0.050
3.03
3.03
5
10-yr
7.88
4.19
5
1.63
0.13
1.50
0.35
n/a
475.0
0.050
2.84
2.84
5
10-yr
7.88
4.50
6
0.23
0.05
0.18
0.45
n/a
300.0
0.040
2.18
2.18
5
10-yr
7.88
0.82
7
6.52
0.50
6.02
0.35
n/a
1100.0
0.040
5.92
5.92
5
10-yr
7.88
17.98
8
0.53
0.12
0.41
0.45
n/a
765.0
0.005
9.96
9.96
10
10-yr
6.31
1.50
9
3.27
0.25
3.02
0.35
n/a
450.0
0.025
3.56
3.56
5
10-yr
7.88
9.02
10
0.24
0.06
0.18
0.45
n/a
350.0
0.006
5.26
5.26
5
10-yr
7.88
0.85
11
0.20
0.05
0.15
0.45
n/a
300.0
0.030
2.43
2.43
5
10-yr
7.88
0.71
12
2.24
0.17
2.07
0.35
n/a
655.0
0.030
4.44
4.44
5
10-yr
7.88
6.18
13
0.07
0.02
0.05
0.45
n/a
100.0
0.050
0.86
0.86
5
10-yr
7.88
0.25
14
1.33
0.20
1.13
0.40
n/a
400.0
0.040
2.72
2.72
5
10-yr
7.88
4.19
15
0.14
0.03
0.11
0.45
n/a
200.0
0.030
1.78
1.78
5
10-yr
7.88
0.50
16
26.84
0.00
26.84
0.30
n/a
2320.0
0.025
12.60
12.60
15
10-yr
5.32
42.84
17
3.77
0.87
2.90
0.45
n/a
1000.0
0.010
9.38
9.38
10
10-yr
6.31
10.70
18
1.31
0.20
1.11
0.40
n/a
900.0
0.010
8.65
8.65
10
10-yr
6.31
3.31
19
1.91
0.29
1.62
0.40
n/a
650.0
0.015
5.76
5.76
5
10-yr
7.88
6.02
20
0.17
0.04
0.13
0.45
n/a
300.0
0.010
3.71
3.71
5
10-yr
7.88
0.60
21
1.24
0.19
1.05
0.40
n/a
400.0
0.015
3.96
3.96
5
10-yr
7.88
3.91
22
0.16
0.04
0.12
0.45
n/a
275.0
0.005
4.53
4.53
5
10-yr
7.88
0.57
23
0.77
0.12
0.65
0.40
n/a
245.0
0.030
2.08
2.08
5
10-yr
7.88
2.43
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Ditch No.
Drainage
Area (ac)
Impervious
Area (ac)
Grassed
Area (ac)
C
Tc
Storm
Event (yr)
Rainfall
Intensity
Q (cfs)
Kerby
Kirpich
Total Tc
Tc Used
L ft n s
Tom
L ft
S
Tab
in/hr
24
0.26
0.06
0.20
0.45
n/a
300.0
0.010
3.71
3.71
5
10-yr
7.88
0.92
25
0.13
0.03
0.10
0.45
n/a
190.0
0.005
3.41
3.41
5
10-yr
7.88
0.46
26
1.46
0.34
1.12
0.45
n/a
450.0
0.025
3.56
3.56
5
10-yr
7.88
5.18
27
4.40
0.34
4.06
0.35
n/a
950.0
0.015
7.71
7.71
10
10-yr
6.31
9.72
28
1.26
0.19
1.07
0.40
n/a
700.0
0.005
9.31
9.31
10
10-yr
6.31
3.18
29
19.60
3.02
16.58
0.40
n/a
1890.0
0.030
10.03
10.03
10
10-yr
6.31
49.47
30
0.22
0.05
0.17
0.45
n/a
250.0
0.050
1.74
1.74
5
10-yr
7.88
0.78
31
1.15
0.18
0.97
0.40
n/a
300.0
0.040
2.18
2.18
5
10-yr
7.88
3.62
32
11.02
0.85
10.17
0.35
n/a
1500.0
0.030
8.39
8.39
10
10-yr
6.31
24.34
33
10.91
0.84
10.07
0.35
n/a
1200.0
0.025
7.58
7.58
10
10-yr
6.31
24.09
34
6.77
1.04
5.73
0.40
n/a
1100.0
0.020
7.73
7.73
10
10-yr
6.31
17.09
35
0.23
0.05
0.18
0.45
n/a
150.0
0.005
2.84
2.84
5
10-yr
7.88
0.82
36
0.35
0.08
0.27
0.45
n/a
550.0
0.005
7.73
7.73
10
10-yr
6.31
0.99
37
6.36
0.49
5.87
0.35
n/a
1300.0
0.030
7.52
7.52
10
10-yr
6.31
14.05
38
4.85
0.37
4.48
0.35
n/a
900.0
0.060
4.34
4.34
5
10-yr
7.88
13.38
39
15.10
1.16
13.94
0.35
n/a
1600.0
0.040
7.90
7.90
10
10-yr
6.31
33.35
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