WSP04095 - Laserfiche WebLink

Home Browse Search

PART I I I . COLORADO RIVER WATER QUALITY ASSESSMENT S") An important objective of this water quality investigation is to assess the suitability of Colorado River water for various beneficial uses. The Water Quality Office or Department of Health of each State was asked to submit an inventory of water pollution problems and/or priorities for users of the Colorado River water within its State. Section H, Main Stem Reservoir Quality, summarizes some of the water quality concerns of the Bureau of Rec lama t i on. r-' -J ..,. A. ~oming Eutrophication of Flaming Gorge Reservoir.--Eutrophication of Flaming Gorge Reservoir is a major water quality problem. An overabundance of algae has resulted in use impairments in the Green River and Blacks Fork Arms of the reservoir. The impaired uses result from a shift from game to nongame fish species and decreased boating and fishing due to aquatic growth snagging propellers and fishing gear. Eutrophication has impaired the fishery, recreational, and esthetic value of the reservoir. Flaming Gorge Reservoir is the most important recreational area in southwestern Wyoming. The 1978 Clean Water Re rt for Southwestern omin estimated the economic benefits derived from recreatlon at over ml ion. Studies indicate that the reservoir is phosphorus limited. Geologic or natural erosion is estimated to contribute 50 to 60 percent of the total phosphorus load. Municipal and private wastewater treatment plants contribute an estimated 11 percent of the load while nonpoint sources such as overgrazed rangeland, channel modification, and manure runoff were identified as significant. Effective management strategies are li~ited by the lack of detailed knowledge regarding the limnology of Flaming Gorge Reservoir, conflicts between competing uses, and the fact that it may not be feasible to control the eutrophication rate so as to protect beneficial use. A task force has been established and a technical proposal developed involving the numerous State and Federal agencies concerned with this problem. Studies are being conducted by Reclamation, the University of Wyoming, Utah State University, and Western Wyoming College in cooperation with the Wyoming Department of Environmental Quality and the EPA to evaluate possible solutions. Salinity of Green River Basin.--The primary impact of salinity loads and concentration in the Green River system is on water users on the Lower Colorado River. The salinity levels in the Green River Basin within the State of Wyoming are generally within acceptable criteria for existing uses. Most of the increased load comes from the area encompassing the Big Sandy River drainage. The salt loading is due to nonpoint sources associated with geologic erosion, overgrazing, irrigation return flows, and natural ground water discharges. Although the water quality is generally adequate for industries, wildlife and livestock watering, and public water supplies, studies have identified III-l -