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Gypsum Loan Feasibility Outline CWCB Water Project Loan Program Page 25 of 33 reseeded to maintain access to the upper end of the 30" HDPE section of the ditch. The access will be on top of the pipe/ditch. b. LEDE Reservoir The wheel gate operator and dam outlet pipe are showing signs of wear and rust. Raising the dam height requires replacing the outlet pipe and replacing the trash rack. We propose that the entire outlet works be replaced. The excavation just for replacing the existing outlet pipe is significant. A large portion of the existing dam would need to be removed. For the cost estimate we assumed removing the entire existing dam and replacing it in place. In 2002, a site survey was performed that established project elevations for study purposes. The existing spillway elevation was determined to be 994.50. This is the basis for all of the elevations listed herein. The spillway elevation will be raised 9.5 feet to Elev. 1004.00. The dam crest will be raised 14.5 feet, to Elev. 1014.00 to maintain the necessary 5 foot of freeboard during peak flows. The 2007 state regulations require the dam crest width to be 20 feet. A grouted slurry/pressure grout cut-offwall expected to be required is 400 feet wide by 30 feet deep. This will be highly dependent upon further soil and geotechnical investigations. The spillway is required to meet current design standards for an IDF based on 0.70 PMP. The spillway will be widened to a base width of 40 feet from its current 16 feet. At a 2 percent slope, the depth of flow at the dam is 5 feet and with 5 feet of freeboard, which calculates 14.5 feet dam crest height increase. We estimated that the spillway will require grouted riprap the entire length due to velocities and volume of flow. 2.4.3 Cost Estimate The following tables outline preliminary cost estimates for the LEDE Ditch and Alternative #3 for the LEDE Dam construction.