SW6240201_Design Calculations (Riprap)_20240213

OUTLET PROTECTION DATE DESIGN PHASE
DESIGN 12-21-23 PRELIM / /
PROJECT NAME PROJECT NO CONSTR / X /
Langdon Preserve Subdivision 2005 REVISION / /
LOCATION BY RECORD / /
Harnett County, North Carolina CEK OTHER / /
CHECKED BY (SPECIFY)
CSB
Storm Outlet Structure
FES No.= PIPE 1 OUT Qio/Qfull = 0.31
Pipe Dia= 18 in V/Vfull = 0.87
Q10= 2.49 cfs V= 3.9 fps
Qfull = 7.98 cfs
Vfull = 4.51 fps
From Fig. 8.06.b.1: Zone = 2
From Fig. 8.06.b.2: D5o = 8 in
DMAX = 12 in
III
:•:•:•:•:•: Riprap Class = B
i�����i���� L Apron Thickness = 18 in
0•0-0•0•0•: _�•������=�� 3 Apron Length 9.0 ft
1••�••�••�••�••�••�•• Apron Width @ Outlet = 4.5 ft
Apron Width @ End = 10.5 ft
Length
Storm Outlet Structure
FES No.= PIPE 2 OUT Q1o/Qfull = 0.88
Pipe Dia= 18 in V/Vfull = 1.13
Q10= 7.14 cfs V= 5.2 fps
Qfull = 8.10 cfs
Vfull = 4.58 fps
From Fig. 8.06.b.1: Zone = 2
From Fig. 8.06.b.2: D5o = 8 in
DMAX = 12 in
Riprap Class = B
s Apron Thickness = 18 in
3 Apron Length = 9.0 ft
Apron Width @ Outlet = 4.5 ft
Apron Width @ End = 10.5 ft
Length
2005-Storm drainage.xlsx LATEST REVISION:2/13/2024 7:29 AM PAGE 1 OF 2

OUTLET PROTECTION DATE DESIGN PHASE
DESIGN 12-21-23 PRELIM / /
PROJECT NAME PROJECT NO CONSTR / X /
Langdon Preserve Subdivision 2005 REVISION / /
LOCATION BY RECORD / /
Harnett County, North Carolina CEK OTHER / /
CHECKED BY (SPECIFY)
CSB
Storm Outlet Structure
FES No.= PIPE 3 OUT Q1o/Qfull = 0.42
Pipe Dia= 18 in V/Vfull = 0.94
Q10= 7.68 cfs V= 9.6 fps
Qfull = 18.08 cfs
Vfull = 10.22 fps
From Fig. 8.06.b.1: Zone = 3
From Fig. 8.06.b.2: D5o = 10 in
DMAX = 15 in
Riprap Class = 1
:44444.1* Apron Thickness = 22.5 in I
3 Apron Length = 12.0 ft
Apron Width @ Outlet = 4.5 ft
Apron Width @ End = 13.5 ft
Length
2005-Storm drainage.xlsx LATEST REVISION:2/13/2024 7:29 AM PAGE 2 OF 2