Laserfiche WebLink
1985 September E, 19E6 <br /> Capacity Total Capacity Capacity Total Capacity <br />Elevation (AC-Ft) (Ac-Ft) Ac-Ft) (Ac-Ft) <br />6946.0 <br /> 2.985 15.01 2.985 13.72 <br />6947.0 <br />6948.0 <br />3.304 18.31 3.304 77.02 <br />At the principal spillway elevation of 6945.2, the 7985 sediment storage capacity was 9.96 <br />ac-ft; whereas, the September 8, 1986 sediment survey indicates a sediment storage volume <br />of 8.67 ac-ft. The difference in sediment storage of -1.29 ac-ft can be attributed to <br />additional sediment being deposited during the year and possible surveying inconsistencies <br />from one year to the next. <br />Based on the updrainage watershed characteristics, one 10-year, 24-hour precipitation <br />event would generate 4.28 ac-ft of sediment using M. U.S.L. E. <br />The equivalent of the sediment generated from approximately two 10-year, 24-hour <br />precipitation events could be stored beneath the principal spillway elevation based on the <br />1986 annual sediment survey. This is an adequate amount of sedf ment storage; therefore, <br />no remedial sediment clean-out work is scheduled during the next year at this time. <br />Sedimentation Pond 007 <br />Design information and calculations for this pond were submitted in a Technical Revision <br />(August 14, 1986) to the Seneca II Permit Renewal Application and subsequently approved by <br />CMLRD. This pond, a new pond, was constructed, in the fall of 1986. The pond will be <br />utilized for approximately one year while Sedimentation Pond 008 is being constructed. <br />Upon completion, Pond 008 will replace Pond 007. <br />Based on the updrainage watershed characteristics, one 10-year, 24-hour precipitation <br />event would generate 3.54 ac-ft of sediment using M.U.S.L. E. <br />I ~ With the principal spi l7way elevation at 7049.35, Pond 007 can store approximately 6.61 <br />ac-f t, or the equivalent of the sediment generated from approximately 1.9 10-year, 24-hour <br />G-6 <br />