SW6220501_Design Calculations (100-Yr)_20220621

DESIGN REQUIREMENTS:
A. Pass the storm event
Drainage Area, (DA) = 2.59 acres
Intensity, (I) = 10.30 inches/hr
Composite Runoff Coefficient, (C) _> 0.30
Maximum Release Rate, (Q100) _> 8.00 cfs
Drainage Area, (DA) = 2.59 acres
Intensity, (I) = 10.30 inches/hr
Composite Runoff Coefficient, (C) _> 0.72
Peak Release Rate, (Q100) _> 19.21 cfs
Contour
Contour
Incr.
Accum.
Stage
Elev.
Area
Storage
Storage (S)
(Z)
00
(sf)
(cf)
(cf)
00
In (S)
In (Z)
Z est
202.5
7,917
-
-
-
203.0
9,203
4,280
4,280
0.50
8.36
-0.69
0.54
203.5
9,781
4,746
9,026
1.00
9.11
0.00
1.02
204.0
10,443
5,056
14,082
1.50
€ 9.55
0.41
1.49
204.5
11,121
5,391
19,473
2.00
€ 9.88
0.69
1.97
205.0
11,818
5,735
25,208
2.50
10.13
0.92
2.47
205.5
12,530
6,087
31,295
3.00
€ 10.35 €
1.10
2.97
206.0
13,242
6,443
37,738
3.50
10.54
1.25
3.49
206.5
13,954
6,799
44,537
4.00
10.70
1.39
4.03
207.0
14,666
7,155
51,692
4.50
€ 10.85 €
1.50
4.58
Regression Output:
b= 1.16 (X Variable Coeff)
Ks- 8,842 (eY-i ter-pt)
Stage - Storage Equation is of the form: S = (Ks)(Z)b
printed: 6/21/2022 7:49 AM Page 1 of 3

Barrel
Number of Barrels =
Dia. of Barrel =
Area of Barrel, (Ab) _
Pipe Length, (L) _
Friction Coeff, (Kp) _
Inv. of Barrel =
Riser
Elev. of Riser Crest
Rectangular
Length Weir— 24 inches
Total Weir Length=
Area of Riser =
Orifice in Riser
Dia. of Orifice =
Number of Orifices =
Area of Orifice, (Ab) _
Orifice Coefficient (Cd) _
Inv. of Orifice =
Length of weir —
Top of weir —
Weir Coefficient (Cw)—
Width of Spillway (Approx.) _
Weir Coefficient =
Crest Elevation =
Maximum Release Rate, (Q100) _
Release Rate, (Q100) _
Normal Water Surface Elev. _
1
24 inches
3.14 sf
III feet
0.01058
202.50 feet
205.00 feet
Width Weir— 36 inches
10.00 feet
6.00 sq. ft.
1.70 inches
1
0.02 sf
0.60
202.50 feet
1.60 feet
203.36 feet
3.00
57 feet
3.3
206.00 feet
8.00 cfs
13.49 cfs
202.50 feet
Water Surface Elev. @ Outlet (Qloo) = 205.15 feet
printed: 6/21/2022 7:49 AM
Page 2 of 3

Peak Inflow, (Qp) =>
Time to Peak Calculation: CN=
Q*=
vo1=
Time to Peak, (Tp) _>
(SCS TR-55)
19.21 cfs
81 P= 8.6 in. S= 2.35 in.
6.31 in. (depth of runoff)
59,328 cf (vol. of runoff)
37.0 minutes
printed: 6/21/2022 7:49 AM
Page 3 of 3