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Long Hollow Dam and Reservoir Phase I Summary Report <br /> Taylor is a long-time member of the LPWCD Board who has expressed great support for the <br /> LHR project. The fourth landowner, who owns about 10 acres of land that would be inundated at <br /> the upstream end of Long Hollow, was notified during the 404 Permit application process and <br /> has not provided any comments to LPWCD. <br /> LHR will not divert water directly from the La Plata River. Inflows to LHR will consist of Long <br /> Hollow flows, derived primarily from precipitation within the watershed and groundwater return <br /> flows from irrigation. No easements for inflow ditches or pipelines are anticipated to be needed. <br /> 8.4 Reconnaissance-Level Opinion of Cost and Financing <br /> WWE's reconnaissance-level (+1-50%) opinion of the cost for LHR set out below was developed <br /> using only limited geological data and without geotechnical field testing or detailed engineering <br /> information for the LHR site. <br /> Harris Water Engineering previously prepared a reconnaissance-level area-capacity study for-the <br /> LHR dam and reservoir (Harris, 1995). This study indicated that a dam at the site with a crest <br /> elevation of 6,314 feet (streambed elevation is 6,200 feet) would have a storage capacity of <br /> approximately 5,432 AF. The H-P engineering geology study, discussed in Section 4.0 of this <br /> report, the topography generated by PWT, reviewed in Section 3.0, and the Harris Water <br /> Engineering area capacity study were used for developing WWE's opinion of cost. <br /> The reconnaissance-level opinion of cost assumes a 125-foot-high earth and rock fill dam, with a <br /> crest elevation of 6,325 feet, a crest length of 850 feet, and freeboard of 15 feet. The <br /> embankment would have a 3:1 downstream slope and a 2.5:1 rock fill upstream slope. A cutoff <br /> trench wall is included. There would be 3 feet of soil stripping over the full footprint of the <br /> embankment. The outlet works would consist of a 6-foot-diameter pipe encased in reinforced <br /> concrete with a suitable intake screen or screens to inhibit fish release. A valve control house <br /> and tower would provide access to the outlet pipe valve. A left abutment spillway, with a crest <br /> length of 400 feet and a gate structure, would discharge into a rock excavated spillway channel <br /> 150 feet wide and 1,500 feet long. The rock from the spillway and discharge chute cut would be <br /> 991-077.115 Wright Water Engineers, Inc. Page 20 <br /> July 2004 <br />