WSP10161 - Laserfiche WebLink

Home Browse Search

to: ~ C'", c._ "" ENVIRONMENTAL IMPACT STATEMENT SUMMARY Late season water quality 1n the Gunnison River below Dominguez Dam would be improved. Lands upstream and downstream from the reservoir would be acquired and managed for fish and wildlife. Backwater ponds would be developed, and nesting structures would be built along the river downstream from the dam. Zoning would be established around portions of the reservoir for the .protection of wildlife species. Multilevel outlets at Dominguez Dam would make possible adjustment of downstream water temperature, thus helping to preserve native fish habitat. Summary of Impacts Geologic considerations The two plans involving reservoirs--plans 3 and 9--have important geologic considerations, while plans 7 and 8 do not. Reservoir construc- tion along the Gunnison River under plans 3 and 9 would likely renew landslide movement where existing slump areas occur. Project features would be located away from susceptible areas. Bank storage of water in formations comprising the reservoir basins would occur with a depletion of an estimated 3,000 acre-feet annually under plan 3 and a somewhat higher but unquantified loss under plan 9. The dams would be designed to withstand e'arthquake activity and water storage would not induce seismic activity. A minor amount of gravel and sand deposits would be inundated by the reservoirs under plans 3 and 9. Land use The immediate project area 1S used primarily for dryland grazing, irrigated crop production, and as a transportation corridor. In the future, limited housing development and loss of wildlife habitat will Occur but the arid conditions should slow changes. Plans 7 and 8 would have the least impact on land use with less than 2,000 acres required for wildlife habitat improvement and preservation of cultural resources. Plan 9 would have the greatest long-term impact on land use with conver- .sion of approximately 36,500 acres, including 18,600 acres of private land, from existing uses to provide for water storage, . recreation, fish and wildlife, and other project purposes. Plan 3 would utilize approxi- mately 26,000 acres including 9,800 acres. of private land. Water resources Flow in the Gunnison River in the immediate proj ect area averages approximately 1,560,000 acre-feet annually. Project purposes would util ize portions of these flows and result in the following depletions from the Colorado River drainage: plan 3, 35,600 acre-feet; plan 7, no depletion; plan 8, 7,400 acre-feet; and plan 9, 250,900 acre-feet. These depletions would represent use by the State of Colorado of part of its apportioned share of Colorado River water. With or without the project, the State is anticipated to continue to develop and use its allotment vi