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This project is a part of the Upper Colorado River Endangered Fish Recovery Program. The project is designed to prevent the Joss of Colorado pikeminnow and razorback sucker 300mm in length or larger into the Grand Valley Irrigation Company system. Much of the design criteria is based on (1) the US Fish and Wildlife Biological Opinion (December 20, 1999), (2) data for juvenile salmon specified by the National Marine Fisheries Service (NMFS), and (3) unpublished research by Mr. Rich Valdez, which developed relationships between total length and body diameter for the two target species. The Grand Valley Irrigation Company (GVIC) diversion is located on the Colorado River 15 miles upstream from the confluence of the Gunnison River, near the City of Palisade, Colorado. Figures 1, 2, and 3 show the project location and existing site conditions. The major components of the existing GVIC system include the diversion dam, flood gates, headworks structure and canal. The GVIC has adjudicated water rights to 640 CFS of water and a 1977 contract agreement to deliver up to another 20 CFS to the Clifton Water District through the GVIC system based on their water right. Typically, "irrigation deliveries are made between April 1 and November 1, and one to two winter deliveries are made outside the irrigation season. The baseline concept, for purposes of comparison with alternative proposals generated by this study, is Option A which is described in the Predesign Memorandum. The baseline concept consists of a trashrack, a sedimentation basin, a fishscreen structure, a fishscreen and a bypass pipe. All the elements of the baseline concept would be contained within the GVIC canal downstream of the headgate structure and upstream of the gauge, except the bypass pipe. The proposed plans of the baseline concept are shown on Figures 4 and 5. The project would bring the GVIC diversion into compliance with the Endangered Species Act (ESA) by separating endangered fish (Colorado pikeminnow and razorback sucker) from the flows diverted from the Colorado River for irrigation. Conceptually, fish entering the canal through the headgate would be separated from the canal delivery flows and returned to the river in a downstream pool through a bypass pipe. The large pool was selected as the best point of return based on its ability to maximize reorientation and minimize predation of fish returning to the river. In conjunction with the installation, the three parties would enter into cooperative, and operation and maintenance agreement(s) to define the planned project scope, cost, reimbursement, and operation. As shown in the Life Cycle Cost Analysis, following Figure 5, the present estimated annual cost of removing sediment from the area in front of the GVIC main headgate and in front of the GVIC flood gates is $18,500. The estimated annual cost of removing sediment from the sedimentation basin, as shown in the Baseline Option (Option A) Figure 4, is $6,475. This would result in an annual savings of $12,025. Based on a 20 year project life and a discount rate of 5.5 percent, the present value of the savings would be $143,703 over the project's life. 5