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Ridgway Reservoir Micro-Hydro Project Loan Feasibility Page 6 of 42 Attempts to proceed at that time were delayed by Reclamation, which had identified potential seismic and hydrologic issues. Reclamation carried out a number of studies, and deternuned that the seismic threat will require corrective action. A recently completed geotechnical study, however, concluded that the area which will most likely require corrective action is the western 2/3 of the embankment, not the east side of the dam where the hydropower unit will be located. Based on the District's current understanding of Reclamation's seismic study, the proposed hydropower facility will be located outside of the area of influence of the corrective effort. In the summer of 2009, the District commissioned HDR to again examine feasibility of the hydro project and decided to pursue development opportunities with Reclamation by requesting a Lease of Power Privilege. Rid�� Ridgway Dam is part of the Dallas Creek Project, which was authorized by Congress as part of the Colorado River Basin Project Act of 1968 (Public Law 90-537). This Act authorized the construction of hydropower faciliries at the dam. Although the principal project brought about by that Act was the Central Arizona Project, it also authorized five projects in Colorado including Animas-LaPlata, Delores, West Divide, San Miguel, and Dallas Creek. The primary feature of the Dallas Creek Project is the Ridgway Dam and Reservoir, which stores water from the Uncompahgre River. Water Ri� Tri-County Water presently controls all water rights for the Dallas Creek Project. An absolute right, which included hydropower as a decreed use, was granted the District under Decree No. 94CW52 with an adjudication date of 1961. A hydropower "direct flow" right was granted to the District and adjudicated under Decree No. 96CW 139. A"second fill" right, which included hydropower as a decreed use, was granted to the District and adjudicated in Decree No. 96CW 140. All of these rights were granted a 1956 appropriation date. Headwaters for the Uncompahgre River are south of Ouray, Colorado, in the San Juan Mountains. Water Delivery Svstem The Bureau of Reclamation constructed Ridgway Dam in the early 1980s and it began storing water in 1987. Water supplies are distributed through facilities owned by the District, the Uncompahgre Va11ey Water Users Association (which purchases a portion of the project water), and private landowners. The reservoir has a capacity of 84,410 acre-feet, including 25,014 acre-feet of inactive storage and 59,396 acre-feet of active storage. The active storage is used to provide water supplies for supplemental irrigation, municipal use, light industrial use, and use at recreational areas. The dam is a rolled earth iill structure rising 227 feet above the streambed. The crest is approximately 2,450 feet long and 30 feet wide. The emergency spillway is an uncontrolled concrete glory hole inlet and includes a conduit buried under the embankinent on the right (east) abutment that discharges into a stilling basin. Normal river releases are made through a single river outlet works that is located near the center of the dam. It consists of a concrete riser with a low-flow drawdown conduit, a concrete and