Laserfiche WebLink
-;. ~- <br />result=_ c` [he sedimentation analysis are <br />Required Sediment Storage Volumes. LRCIdE <br />Energy *?in es Ne. 1 and 2, and Eckman Park <br />each site. The pond volume includes the <br />the routed 10-year 24-hour inflow flood. <br />FLOOD ROUTING <br />summarized in LRCk'E Table ~, <br />Plate 1, Sedimentation Ponds, <br />sets forth the pond volume for <br />required sedimentation volume and <br />The flood routing for all ponds except A assumed an initial water surface <br />at the required sedimentation level. This is the elevation of the lowest <br />set of holes in the riser pipe. For Pond A, a permanent pool elevation of <br />slightly more than the required sedimentation level was assumed because the <br />reservoir will also store 2i acre-feet of irrigation water. Section 816.46 <br />(h) require=_ that the reservoir be cleaned when the sedimentation reaches <br />60~: maximum of the required sedimentation volume. However, after the first <br />significant inflow, a permanent maximum pool elevation equal to the required <br />sedimentation level will develop as this is the elevation of the lowest set <br />of holes on the riser. <br />Actual flood routings were computed for the 10-year, 100-year and PMP inflow <br />floods for Pond A, and the 10-year floods for Ponds D, E, F, and G. The <br />actual flood routings for the 10-year floods for these reservoirs were used <br />to determine the elevation of the crest for their risers. All of the other <br />ponds have a Type 3 riser which limits the outflow rate to such an extent, <br />that the entire 10-year inflow volume was assumed to be stored for the pur- <br />pose of setting the riser elevation. To confirm this assumption the 10-year <br />24-hour inflow flood was routed for Pond K. <br />INTERCEPTOR DITCHES <br /> lnterceptor ditches were used to modify the natural tributary areas to var- <br /> ious ponds in order to maximize the use of favorable ponding locations. The <br /> ditches are located in plan view on Energy Nines No. 1 and 2 Hydrology (EFC <br /> Map 13). They are identified with letters which correspond t o the pond <br />Permit Renewal No. 3 Exhibit 8q ]/15/00 <br />Page 15 of 22 <br />