HYDRO21350

• Permit No: C1981032
• IBM Index Class Name: Hydrology
• Doc Date: 8/7/1984
• From: PANORAMA RESOURCE SERVICES INC
• To: MLR
• Permit Index Doc Type: CORRESPONDENCE
• Media Type: D
• Archive: No

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Current Pond Capacity Requirement Calculations
Pond A
Contributing Area:
Disturbed Area east of Hwy 13 0.50 acres CN 88
Disturbed Area west of Hwy 13 3.45 acres CN 88
Total = 3.95 acres
25 year - 24 hour precipitation = 2.26 inches
Runoff from above storm at CN 88 = 1.17 inches
Pond Volume required to store 25 yr - 24 hr storm =
3.95 acres x 1.17 in x 1 ft = .385 ac.ft.
12in
Sediment volume = 3.95 acres x .1 ac-ft = .395 ac.ft.
acre
Total pond volume required = 0.78 ac-ft
On site measurements on July 25, 1984 showed a pond volume
in excess of 1.0 acre-feet, so that with the diversion
ditches installed, Pond A is capable of holding the zunoff
from the 25 year - 24 hour storm in addition to a
conservative 3 year sediment volume.
Pond B
Contributing Area:
Disturbed Area east of Hwy 13 1.85 acres CN 88
Disturbed Area west 4.05 acres CN 88
Total = 5.90 acres CN 88
Pond Volume required to store 25 yr - 24 hr storm =
5.90 acres x 1.17 in x 1 ft = .575 ac-ft
12in
Sediment volume = 5.90 acres x .1 ac-ft = .590 ac-ft
acre
Total pond volume required = 1.17 ac-ft
On site measurements showed an existing pond volume in
excess of 3.1 acre-feet, so that the pond is more than
capable of storing the inflow from the 25 yr - 24 hr. storm
plus the 3 year sediment volume.