9417 - Laserfiche WebLink

Home Browse Search

I I I I I I I I I I I I I I I I I I depressions that are filled by groundwater and by irrigation return flows, Mitchell (1995) identified 308 ponds (both public and private) representing 878 surface acres along the Colorado and Gunnison rivers. Many of these ponds are less than 5 acres in surface area. On the Colorado River, 73 percent of the ponds are privately owned. On the Gunnison, 44 percent of the ponds are privately owned (Mitchell 1995). By comparison, there are only a handful of (maybe 10) gravel pits along the 80-mile segment of the Green River between Pariette Draw and Dinosaur National Monument. Alternative 1 - No Action Existing land use practices within the floodplain are expected to continue. Vegetation within the floodplain of the Upper Basin is currently a mix of both native and nonnative species. Disturbances often result in an environment that favors nonnative species, Under the No Action alternative, continuation of floodplain land use practices may increase surface acreage of tamarisk, whitetop, and other nonnative species and noxious weeds. Alternative 3 - Protection and Enhancement of Flooded Bottomlands by Acquisition On floodplain properties that are not acquired, land use activities would continue. On acquired properties, land use activities would be also be allowed to continue as long as they do not adversely affect the endangered fishes. Therefore, the response of vegetation where properties are simply acquired and protected (i.e., no habitat enhancements) should be the same as with the No Action alternative. On properties where habitats are enhanced, however, there will likely be some vegetational changes. By restoring floodability, the area would be expected to revert back to a riparian wetland with associated wetland vegetation, The resultant vegetation would consist of species that can withstand seasonal flooding on an annual basis. Mature cottonwoods would be avoided during . habitat enhancement activities. Pond Distribution . Total' of Ponds . >0.5 - 1.0 acres . >5.0 - 25 acres . 0 - 0.5 acres . >1.0 - 5.0 acres . >25 acres 250 200 . ~ 150 u 0( 100 ., 50 o Colorado Gunnison River& Green E. Water Resources Water rights in Colorado and Utah have always followed the western appropriation doctrine in the allocation of water resources. In the past, a water right for surface water was acquired by the diversion of water and its application to a beneficial use that resulted in water depletion. Today, the instream use of water can be acquired for fish and wildlife. Streamflows in the Upper Colorado, Green, and Gunnison rivers are regulated by releases from high dams for irrigated agriculture and power generation. Alternative 1 - No Action The acquisition of water rights and releases from reservoirs would continue as in the past. Water quantity and quality would remain essentially the same. Alternative 3 - Protection and Enhancement of Flooded Bottomlands by Acquisition Along the Upper Colorado, Green, and Gunnison rivers, water rights will not need to be acquired, so impacts to other water users are not expected to III-7