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Chapter II - Project Description and will support a 36-inch sluice gate, enclosed with trashracks. The sluice gate will be located at the intake structure for emergency reservoir releases and to allow access to the pipe for inspection and/or maintenance. A stainless steel gate stem, encased in oil to prevent freezing, will run along the face of the dam to the dam crest, where it will be manually operated. Figure ll-5 shows a plan and profile of the outlet works. The outlet conduit will be an epoxy lined 36-inches ill steel pipe with a 0.5-inch pipe wall thickness. The valve chamber will house a tee connection to a 24-inch pipeline (water delivery system to the pump station), a butterfly valve, a 30-inch fixed cone valve, and a to-inch bypass pipe and fixed-cone valve. The tee provides a connection to the new pump station for reservoir filling and release requirements. The 30-inch fixed cone valve provides the capacity necessary tiO meet emergency reservoir release requirements and the to-inch pipe and fixed cone valve allow low flows to be bypassed. The fixed cone valves are capable of dissipating the head from the reservoir, however for safety purposes, a baffled outlet was designed to contain the discharge jet from the fixed cone valves. The baffle wall is lined with stainless steel to protect the concrete from cavitation. Downstream of the baffled outlet, water will be conveyed by a trapezoidal riprap and grass-lined channel to Dry Creek. D. Raw Water Transmission System The CLFP is currently fed via an influent line from the St. Vrain Supply Canal. Water will be delivered from this influent line to the proposed reservoir by gravity and returned to the CLFP by pumping. A new flow meter will also be installed in the existing raw water supply line feeding the CLFP upstream of where the pump station piping will connect. This meter will allow Northern Colorado Water Conservancy District to identify the flow that is withdrawn from the St. Vrain Canal. The raw water transmission system consists of a 6,300 gpm pump station; a 359-foot-Iong, 24-inch diameter steel waterline between the dam outlet and the pump station; a 6,524-foot-Iong, 24- inch diameter ductile iron pipeline to connect the pump station to an existing 20-inch pipeline (owned by the CWCWD) at the northwest side of the reservoir; and a pipeline to connect from the 20-inch pipeline to the CLFP. A mechanical layout of the pump station is shown in Figures 11-6 and ll-7. Dry Creek Reservoir Project 7 ElClVLE