WSP02110 - Laserfiche WebLink

Home Browse Search

~ '-',", .,<:: ') .....,. ~! __ , : J ... ,. approximately 654 cfs. 300 cfs would increase no-action alternative. The frequency of minimum flow levels of significantly when compared to the In the future, it is recognized that operations of the Aspinall unit may be altered under ,authority of the Endangered Species Act to benefit endangered fishes downstream or under other authorities to protect the BLCA. These operational changes may decrease the water supply to the Facility. Reclamation estimates that fOllowing endangered species consultation, Gunnison River flows downstream from the Aspinall unit would tend to follow the natural hydrograph more than at present. This would result in higher flows during spring runoff and lower fall and winter flows. The FEIS recognizes that alternative E can only use flows as they are released by the reservoir operators and are available for appropriation under the Sponsor's water rights. Future changes to releases represent a certain amount of risk to the sponsors and may affect Facility economic returns. Alternative E, with its lower diversions, would be affected less by such operational changes than would other alternatives. Alternative B Alternative Bwould be similar to alternative E but would have a powerplant with a higher design flow capacity of :1.,135 cfs. Operation methods would be similar to alternativeE, although di versions from the Gunnison River would increase'. Average annual energy production would be 261,000 MWh. An annual average of 354,602 acre-feet of water above and beyond existing irrigation diversions would be diverted from the Gunnison River and average flows downstream from the Gunnison Tunnel would be approximately 613 cfs. ,<} Alternative C ~ Alternative C would be similar to alternative E and would have a design flow capacity of 1,135cfs. operations would be Similar; however, the eapacity of .the Gunnison Tunnel would be increased from 1,135 cfs to 1,300 cfs to allow greater diversions from the Gunnison River during the irrigation season. The average annual energy prOduction would be 274,900 MWh. An annual average of 390,485 acre-feet of water above and beyond existing irrigation diversions would be diverted from the Gunnison River and average annual flows downstream from the Gunnison Tunnel would be approximately 563 cfs. Alternative F :~ Alternative ,F would be simiiar to alternative E and would have a powerplant with a design flow capacity of 1,135 cfs. operation methods would be similar to alternative E; however, during severe cold SPellS additional water bypasses of the Gunnison Tunnel 5 ;~: