PERMFILE66875

• Permit No: C1981016
• IBM Index Class Name: Permit File
• Doc Date: 12/11/2001
• Doc Name: Sedimentation Control & Diversion Structure Calculations
• Section_Exhibit Name: APPENDIX XXI to Section XXI.8
• Media Type: D
• Archive: No

6eah
•
41EST P1INE DIVERSIOPI -WEST LIt?B
Ditch Sizing
1. Q = 15.3 cfs
2. Rearrange Planning Equation
V=1n5P,2 S~
3
V = 1=55(x)- S'z
n P
(A)2/3 = (V n
P (1.5)(S~z)
A = (V n l z
P (1.5)(S z) 1 ,
A _
P - (V n z
(1.5)(S~~),
R=A/P
3. Solve for P if V = 5.0 ft/s => A = Q/V = 3.06 ftz
3.06 ft2
P = f(5.0 ft/s (0.05 z
(1.5)(0.128)2
4. Ditch Geometry
A = '-~~~~
= 9.645 ft
x
y
z
P = Z + Y
X=2Y P= X-+Y +Y
• Assume Y and solve until P = 9.645 ft
If Y = 0.685' _> X = 8.934' _> P = 9.646'