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CHAPTER 2 - PROPOSED ACTIONS AND ALTERNATIVES <br />Proposed Actions <br />Two actions are proposed. One is to construct a fish passageway around the east side (right <br />abutment) of the Redlands Diversion Dam. The other is to provide water when needed from the <br />Aspinall Unit under an interim (temporary) water agreement as needed to operate the fish <br />passageway and maintain downstream flows. Flows required to operate the passageway would <br />either be released from water stored in the Aspinall Unit or consist of natural Gunnison River <br />flows in excess of the needs of the senior downstream Gunnison River Basin water rights, <br />including the Redlands Diversion Dam and the city of Grand Junction. <br />Fish Passaeewav Desi <br />The proposed design for the fish passageway is a concrete chute, 6 -feet wide and 350 -feet long, <br />routed around the Redlands Diversion Dam and the city of Grand Junction's pump station <br />located on the right bank of the river (Figure 1). The chute will be divided into a series of small <br />pools by baffles; the water flow through the chute will be approximately 25 cfs. The upstream <br />entrance to the fish passageway will have a log boom and trash rack to prevent debris from <br />entering. There will be a forebay (widened section of fish passageway) near the upper end that <br />allows fish to be trapped and separated before they move upstream into the river. Non - native <br />fish will be returned to the river downstream from the diversion dam. A concrete wing wall and <br />forebay structure, approximately 80 feet long and extending 2 feet higher than the existing bank <br />will be constructed upstream and downstream from the forebay. <br />The fish passageway forebay, where the entrance to the 42 -inch bypass pipe, baffled chute, and <br />24 -inch Grand Junction pumping plant intake are located, is protected by two sets of trash <br />screening devices. The screening devices prevent floating debris from entering and obstructing <br />the fish passageway structure and also prevent fish from being drawn into the Grand Junction <br />pumping plant intake. The initial screening device consists of a rack of vertical steel bars with <br />4 -inch openings between bars. The secondary screening device also consists of a rack of vertical <br />steel bars; however, the openings between these bars will be only 1/4 -inch wide. No "take" <br />(harm) of endangered species is anticipated by the construction and operation of the fish <br />passageway as the screening devices should prevent fish from being drawn into the city of <br />Grand Junction's pumping plant intake. No "take" is anticipated to occur as a result of the <br />continuing operation of the Redlands Diversion Dam. <br />Successful use of a passageway by razorback suckers and Colorado squawfish is currently <br />undocumented; and water flow velocities, barriers, and attraction to the fish passageway entrance <br />may control whether passage is successful. Therefore, the passageway will be designed to <br />incorporate measures for added flexibility in controlling water velocities and entrance conditions. <br />The design will allow for variation in baffle spacing, pool length, height of water drop between <br />pools, and water flow rates in order to test various conditions. <br />E <br />