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, Roberts Tunnel as the primary mitigation option, capital costs would range from $20 to $25 millon and the annual operation and maintenance costs would range from $300,000 to $500,000. Aqu8tic.Life. A significant impact to fisheries in the Blue River downstream from Green Mountain Reservoir would occur as a result of alterations in the flow regime resulting from the pumping system. This 14.8-mile stream segment is classified as a gold medal stream and a 2.5-mlle segment immediately downstream from Green Mountain Dam is classified as wild trout water. Constructing s diversion dam without fish bypass features on the main stem of the Eagle River could significantly impact the fIshery by blocking the migrstion route, especially if the diversion dam were located downstream from major spawning areas. A sport fishery could be developed .in Eagle-Colorado Reservoir, However, with the expected sediment loading, turbid water conditions would develop. Consequently, the developed sport fishery would be of poor to fair quality and would have to be stocked annually. Mitigation costs for a supplemental fish stocking program would range from $10,000 to $20,000 annually. A fish bypass structure could cost between $10,000 and $100,000, depending on construction requirements. Wetlands and Riparian Areas. Approximately 300 acres of wetland and riparian resources would be affected by the project. Of this amount, approximately 85 percent (250 acres) would be lost because of inundation by the reservoir and would be a long-term adverse impact. Where construction and operational adjustments could avoid or mitigste wetlands impacts, the cost could be approximstely $100 per acre per year. When new wetland creation would be the required form of mitiga- tion, the costs could range from $5,000 to $10,000 per acre, depending on local factors and wetland design. 21