2018-08-08_PERMIT FILE - C1982056 ‎(17)‎

• Permit No: C1982056
• IBM Index Class Name: Permit File
• Doc Date: 8/8/2018
• Section_Exhibit Name: EXHIBIT 08 TAB 1 SEDIMENT CONTROL PLAN
• Media Type: D
• Archive: No

REVISED
7/30/85
Table 2
SEDIMENTATION POND E DESIGN CALCULATIONS
(Continued)
SPILLWAY DESIGN SUMMARY:
- Depth of flow is 0.5 ft.
- Velocity of flow is 5.2 fps
- Bottom of spillway is 1.5 ft below top of dam
- Width of spillway is 13.2 ft across bottom
- Side slopes are lv:2h
- Gradient of spillway is 3k
EMERGENCY SPILLWAY CALCULATIONS:
Broad -crested Spillway Design:
(Applied Hydrology and Sedimentoloey for Disturbed Areas; Barfield,
Warner, Haan: 1981)
Q = 28.6 cfs
Maximum velocity 5.2 fps
L 2v:lh sideslopes
n = 0.04
Slope = 0.03 ft/ft
Hec = 0.75 Fig 48.14
Hp = 0.86 Fig 4B.1
Q' = 0.544(g) 2(Hec)3/2b
Q' = 0.544 (32.2)2(0.75)3/2(100) = 201
Q = 28.6 = Q'(1.5b + 2 Hec)/150
b = 13.2'
Q = 201 (1.5b + 2(0.75))/150
Spillway is 13.2 ft. width across the bottom. Depth of spillway is 1.5
ft. minimum. Will need to riprap emergency spillway.
-10-