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...... ::~. Water is passed through the reservoir to satisfy these downstream waler rights. DOLORES RIVER TIle \Vater supply for the Dolores Riyer below McPhee Dam consists of project water released from storage, waler passed through the reservoir to satisfy senior downstream waler rights, and waler released in anlicipalion of spills and/or actual spills. The DPRlFES criteria for releases to the river specify releasing a either 20, SO, or 78 crs during non-spill periods. These flows consist of project water released from storage and water passed through the reservoir to satisfy senior downstream rights. Water released in anticipation of spills and during acrual spills average abour 76,000 AF. However, spills only occur in about 50% of the years. 111e average annual volume of water released to the Dolores River is approximately 109,000 AF. 2. ENVIRONMENTAL CONSEQUENCES PROJECT WATER USERS ALTERNATIVE 1 - The implementation of this alternative would have no effect oa Project M&1 or Ule Mountain Ute and Totten fish and wildlife development water supplies since these are guaranteed. Varying releases from 35-80 cfs at different times of the year would result in the annual release of less water than the constant release of 50 cfs or 78 cfs as reqUired by the DPR criteria. Greater carryover storage in McPhee Reservoir during normal and high water years would result. This would reduce or eliminate project water shortages resulting from an extremely dry year occurring during such periods. Slightly less water would be available for all users during periods of extended droughts. During drought years all those with Project irrigation water and portions of the fish and wildlife managed would share in water shortages. Based on the Project operation study as presented in the DPR, downstream releases would have been set at 20 cfs during 8 "dry" years of the 46-year study period. During the extended drought of the 1950's, downstream releases would have been set at 20 cfs for three consecutive years. The annual'volume of Project water required to be released from storage to meet the 20 cfs flow requirement is approximaiely 10,600 AF. Even with the condition that the managed pool share equally in Project water shortages with inigation users, the annual volume of water to be released would be higher than 10,600 AF under these alternatives during a similar drought period. All users would share the added shortage represented by the difference between 10,600 M and the amount of water released under a managed pool system during drought years. The highest estimate of additional shortages occurring in any single year as a result of the implementation of these aiternatives is 8% higher than the maximum 39% shortage predicted in the Project operations study. This type of shortage would occur only in successive drought years. The Dolores Water Conservancy District has made an offer to Reclamation to provide at least 7,200 AF of water on a continuous basis. Aside from the 3,900 acre feet of municipal and industrial water being offered, the source of the remaining water may vary from year to year. This remaining 3,300 acre feet of water would consist of a combination of unused Project and non-Project water. Under this acquisition scenario, no' significant impacts would occur to the individuals or enlilies supplying all or part of chis sucplus wacer. ALTERNATIVE 2 - The effects of this alternative would be similar to those of Alternative I, except Ihat higher volumes of Project irrigation water may be acquired. This may hav~ the effect of exacerbating shared shortages during periods of extended drought. ALTERNATIVES 3 AND 4 . Adequate water would be availablcto develop all Project land as originally planned, if no Project irrigation water is acquired to implement Alternative 3.a ALL ALTERNATIVES. The reduction in potential future reLUm flows would be the same as 34