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Monitoring perfonnance of the passageway and fish behavior under variations in the passageway will help detennine the design parameters necessary for successful passage. This facility will serve as an example for future passageway facilities within the Colorado River Basin by helping develop specific design criteria for endangered fish. An existing sediment bar along the east bank of the river will be dredged as necessary at the upper end of the fish passageway to facilitate water movement. A 42-inch bypass pipe will be constructed underground and adjacent to the chute. This bypass pipe will carry water (approximately 75 cfs) into the river below the Redlands Diversion Dam to attract fish to the passageway structure and to maintain habitat downstream. A 12-inch pipe will also parallel the fish passageway to return non-native fish captured in the fish trap, thus preventing them from moving upstream into the Gunnison River. The passageway site will be fenced with a 6-foot-high fence for facility and public safety; a bridge over the passageway will pennit vehicle access to the right side of the Redlands Diversion Dam and the city of Grand Junction's pumping plant. The overall concept and design of the fish passageway was developed through a series of studies, reviews and meetings conducted cooperatively among the Service, Redlands Water and Power Company, Reclamation, the Recovery Implementation Program, the city of Grand Junction, environmental organizations, and the states of Colorado, Utah, and Wyoming. A more detailed description of the fish passageway is contained in Appendix A. Fish Passa2eway Construction The proposed passageway will be constructed on land owned by the Redlands Water and Power Company. Property interest (a petpetual easement) has been acquired by the United States. The city of Grand Junction also has a lease on the land for their pumping facilities. The passageway will be built under a contract administered by Reclamation; funding will be provided by Reclamation through the Recovery Program. The construction area is comprised of river alluvium overlain at some locations by 2 to 10 feet of fill material. The fill was apparently obtained from the immediate area and consists primarily.' of lean clay with sand, silty lean clay with sand, and silty sand with some gravel at the surface. Along the alignment of the fish passageway, the alluvium consists of up to 9.5 feet of fme- grained material overlying an unknown thickness of coarse gravel and cobbles. The coarse gravel and cobbles lie on bedrock (Morrison Fonnation) at an unknown depth. The groundwater table in the area is quite sballow and appears to be directly controlled by the river-water elevation. Standard construction practices will be used. Excavators and similar construction equipment will be needed to perfonn required earthwork. Sheetpiling or cofferdams and dewatering will be required for work in some excavations and in the river channel. A Section 404 pennit under 7