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Gypsum Loan Feasibility Outline CWCB Water Project Loan Program Page 23 of 33 spillway would be required. This would probably result in loss of overall storage capacity. The State would likely require the dam to be at least partially breached, probably by lowering the spillway. Choosing this alterna.tive will also reduce long-term viability of the senior water rights. ii. Alternative # 2 The second alternative explored is to bring the current dam and infrastructure up to 2007 dam safety regulations for a Small High Hazard Dam, without increasing capacity. This would entail raising the crest of the dam by 5 feet, extending the crest width to a minimum of 20 feet, replacing the existing outlet pipe, replacing the gate valve and inlet trash rack, modifying the spillway width and length downstream. In addition to dam improvements, the LEDE Ditch would require the installation of a new head gate, the first 860 feet of 30" CMP pipe requires joint repairs and an additional 1900 feet of the ditch be piped through the conifer area to increase water yield, minimize erosion and maintenance requirements and improve the access to the head gate. This alternative would not increase the existing storage capacity or yield of the reservoir but would preserve the existing capacity. The operation and maintenance costs would be less than Alternative 1 but basically equa.l to Alternates 3 and 4. Alternative #2 does not assist with Gypsum's long term goals for meeting existing and growing water needs, and it risks losing some of Gypsum's water rights. The construction estimate for this alternative is $342,000 for the ditch and $2,150,000 for the dam for a total of $2,500,000 (Appendix 7). iii. Alternative # 3 The third alternative evaluated envisions maximizing LEDE Reservoir storage yield within an acceptable and cost effective risk level by maintaining the assumed existing rating of a Small High Hazard Dam, the dam's jurisdictional height could be raised an additional 9.5 feet, to 49 feet, and maintain the same rating. This would raise the crest height of the dam 14.5 feet. The crest width would be extended to 20 feet. The existing outlet pipe would be replaced and the spillway would be modified in width and length downstream. In addition to the dam improvements, the LEDE ditch would require the installation of a new head gate, the first 860 feet of 30" CMP pipe requires joint repairs and an additional 1900 feet of the ditch be piped through the conifer area to increase water yield, minimize erosion and maintenance requirements, and improve head gate access. Approximately 254 acre feet of additional storage would be added to the dam, for a total of approximately 685 acre feet of storage (See Appendix 6). Maximum storage potential could be carried over from wet to dry years. The operation and maintenance costs would be less than Alternative 1, but basically equal to Alternates 2 and 4.