PERMFILE66828

• Permit No: C1981018
• IBM Index Class Name: Permit File
• Doc Date: 5/13/2002
• Doc Name: Calculations for 2 Ponds on the South Side of Railroad Loop Fill Slope
• Section_Exhibit Name: Illustration 40
• Media Type: D
• Archive: No

AREA #2 - POND R2
Pond Design
1. Drainage area: 5.12 acres
2. Equivalent drainage area: 5.12 acres
3. A. 10-year 24-hour storm = 1.8 in.
B. F:o:~ runoff chart 85 = .65 in..
C. Total volume of runoff = .2773 acre-feet,
4. Sediment storage from universal soil loss equation =
8.55 T/A/Y or .0754 acre-feet total for three years
f v
5. Total sediment + runoff storage = .3527 acre-feet
Spillway Design
1. Maximum flow
• 2. From h;anning
1~ slope and
3. Crest of pone
of runoff (type II Storm) = 11.2 CFS'
equation, a trapezoid ditch 5' ::ide at bottom,
2:1 sides at a floc; elevation .75' = 14.39 CFS ~
3 1' above flow ele~•ation of spill::ay.
•