Dimensions:
23” Wide 24” Tall

Concrete Outlet Pipes Covered
15” and less

Total Flow in 15”
Concrete Pipe with
following slopes
0.50% Slope 5 cfs
1.00% Slope 7 cfs
2.00% Slope 9 cfs

Total Flow
Hydraulic Calculations

30” Deep Stormdrain
Clean 3 cfs

48” Deep Stormdrain
Clean 5 cfs

Drainage Area Required
for 10 year storm
3 cfs 19,578 Sq. Ft.
5 cfs 29,163 Sq. Ft.

30"’ Deep Stormdrain
12” Debris 2 cfs

48” Deep Stormdrain
12” Debris 3 cfs

Drainage Area
Required for 10 year storm
2 cfs 12,719 Sq. Ft.
3 cfs 20,068 Sq. Ft.

Extended from Wall 4"

30" Deep Stormdrain Clean 6.90 cfs
48" Deep Stormdrain Clean 9.99 cfs

Drainage Area Required for 10 year Storm
6.90 cfs 43,945 Sq. Ft.
9.99 cfs 63,625 Sq. Ft.

30" Deep Stormdrain 12" Debris
3.50 cfs
48" Deep Stormdrain 12" Debris
5.45 cfs

Drainage Area Required for 10 year
Storm
3.50 cfs 22,291 Sq Ft.
5.45 cfs 34,710 Sq. Ft.

Dimensions
28” Wide 30” Tall

Concrete Outlet Pipes Covered
18” and less

Total Flow in 18”
Concrete Pipe with
following slopes
0.50% Slope 7 cfs
1.00% Slope 11 cfs
2.00% Slope 15 cfs

Total Flow
Hydraulic Calculations

36” Deep Stormdrain
Clean 4 cfs

60” Deep Stormdrain
Clean 6 cfs

Drainage Area Required
for 10 year storm
4 cfs 25,641 Sq. Ft.
6 cfs 40,652 Sq. Ft.

36” Deep Stormdrain
18” Debris 2 cfs

60” Deep Stormdrain
18” Debris 4 cfs

Drainage Area
Required for 10 year storm
2 cfs 14,266 Sq. Ft.
4 cfs 25,253 Sq. Ft.

Extended from Wall 4"

36" Deep Stormdrain Clean 9.92 cfs
60" Deep Stormdrain Clean 15.38 cfs

Drainage Area Required for 10 year Storm
9.92 cfs 63,179 Sq. Ft.
15.38 cfs 97,953 Sq. Ft.

36" Deep Stormdrain 18" Debris
4.36 cfs
60" Deep Stormdrain 18" Debris
7.72 cfs

Drainage Area Required for 10 year
Storm
4.36 cfs 27,768 Sq. Ft.
7.72 cfs 49,168 Sq. Ft.

Dimensions:
34” Wide 36” Tall

Concrete Outlet Pipes Covered
24” and less

Total Flow in 24”
Concrete Pipe with
following slopes
0.50% Slope 16 cfs
1.00% Slope 23 cfs
2.00% Slope 32 cfs

Total Flow
Hydraulic Calculations

42” Deep Stormdrain
Clean 7 cfs

72” Deep Stormdrain
Clean 12 cfs

Drainage Area Required
for 10 year storm
7 cfs 43,977 Sq. Ft.
12 cfs 73,490 Sq. Ft.

42” Deep Stormdrain
24” Debris 3 cfs

72” Deep Stormdrain
24” Debris 6 cfs

Drainage Area
Required for 10 year storm
3 cfs 20,482 Sq. Ft.
6 cfs 40,258 Sq. Ft.

Extended from Wall 4"

42" Deep Stormdrain Clean 14.57 cfs
72" Deep Stormdrain Clean 23.28 cfs

Drainage Area Required for 10 year
Storm
14.57 cfs 92,794 Sq. Ft.
23.28 cfs 148,267 Sq. Ft.

42" Deep Stormdrain 24" Debris
5.12 cfs
72" Deep Stormdrain 24" Debris
9.78 cfs

Drainage Area Required for 10 year
Storm
5.12 cfs 32,609 Sq. Ft.
9.78 cfs 62,287 Sq. Ft.