Laserfiche WebLink
Ray Lazuk <br />March 19, 2014 <br />Page 4 <br />near the Property Discharge Water Treatment Plant (PDWTP). The East Interceptor System <br />intercepts runoff that would otherwise flow into McNulty Gulch, Robinson TSF, Tenmile TSF, <br />Mayflower TSF, the 3 Dam seepage collection system, and the 5 Dam seepage collection <br />system. The East Interceptor system does not impact the natural Clinton Reservoir watershed. <br />The reaches from McNulty Gulch to the south end of Tenmile TSF and from 3 Dam to Clinton <br />Reservoir are piped with periodic inlets. The remainder of the interceptor system is open <br />channel. As part of this system, several culverts convey runoff under Highway 91 and direct <br />that runoff to inlets into the East Interceptor system. Figure 3 provides a general arrangement <br />map of the East Interceptor system. <br />2.3 West Interceptor <br />The West Interceptor extends for approximately 32,000 feet along the west side of the Tenmile <br />Creek valley. This system intercepts Kokomo Creek, Searle Gulch, several unnamed <br />drainages, and overland surface runoff from the west side of the valley and discharges into <br />Tucker Creek. This system intercepts runoff that would otherwise flow into Robinson TSF, <br />Tenmile TSF, Mayflower TSF, the 3 Dam seepage collection system, and the 5 Dam seepage <br />collection system. The open canal begins just north of Lake Irwin near the west abutment of 2 <br />Dam and extends to Searle Gulch, where the canal transitions into buried pipe. The buried pipe <br />section collects surface runoff thru several inlets and eventually discharges into Tucker Creek <br />between 5 Dam Pump Station and the PDWTP. Figure 4 provides a general arrangement map <br />of the West Interceptor system. <br />3.0 HYDROLOGY <br />The HEC -HMS model was used to evaluate the rainfall -runoff relationships for each of the <br />subbasins tributary to the interceptor systems. The key parameters associated with developing <br />the inflow hydrology for the rainfall discharges for the site are summarized below. <br />3.1 Drainage Basin Characteristics <br />Figure 1 shows the overall watershed boundaries for the three interceptor systems. Figures 2, <br />3, and 4 show the individual drainage basins that were modeled in HEC -HMS for the Chalk <br />Mountain Interceptor, East Interceptor, and West Interceptor systems, respectively. The <br />