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Mr. Calvin Joyner 3 c-' c C-:', t,.) ~ ClO evaporative losses from various sized reservoirs and stock/wildlife ponds, and there is one special use permit for the pagosa Fire District. There is 30.36 acre-feet of water depletion that will occur as a result of 1996-1997 proposed projects on the Columbine and Pagosa Ranger Districts. These projects will deplete water by using it at ski area facilities, for stock/wildlife ponds, and for an oil or gas field development. t ~fThe Forest Service's January 25, 1996, biological assessment states there is . 31,841,52 acre-feet of pre-1983 water depletions, 854.11 acre-feet of r6~ 1983-1995 water depletions, and 30.36 acre-feet of 1996-1997 water depletions. r~"'Ai Both of the pre-1983 and 1983-1995 amounts have been changed from the total s ~\~~. stated in the previous paragraph and the changes were hand written on the ~'~? biological assessment. The changes in the biological assessment are as follows: For the pre-1983 depletions, one of the projects showed a zero acre-foot depletion but should have shown the depletion as 1,500 acre-feet. An additional pre-1983 project for which the Forest Service had information was accidentally left off the list and that project depletes 1,100 acre-feet. A project that was in the post-1982 list was actually constructed and operating prior to 1983 and its 214.8 acre-feet depletion also was added to the pre-1983 total, For the post-1982 depletions, the 214.8 acre-foot project was subtracted and a project that was described as depleting 386.1 acre-feet was only routing water around a small reservoir for a few years without using the water and; hence, there was no depletion so that depletion was subtracted from the post-1982 total. tie ~ pr",/lj'~.U6SI,,~Z 3.,-'1S'l!J3.S7 w~.... :SAS1S FOR BIOLOGICAL OPINION This biological opinion addresses a total average annual depletion of approximately 34,939.89 acre-feet from the San Juan River. Water depletions in the San Juan River Basin have been recognized as a major source of impact to endangered fish species. Continued water withdrawal has restricted the ability of the San Juan River system to produce flow conditions required by various life stages of the fishes. In 1963, the Navajo Dam was closed and Navajo Reservoir began to fill with water from the San Juan River. Historically, flows in the San Juan River prior to the Navajo Dam were highly variable and ranged fr~ a low of 44 cubic feet per second (cfs) in September 1956 to a high of 19,790 ~ in May 1941 at the U.S. Geological Survey Station 93680000, Shiprock, New Mexico. Conversely, post-Navajo Dam flows in the San Juan River have ranged from a low of 185 cfs in July 1963, while the reservoir was filling, to a high of 9,508 cfs in June 1979. According to the Bureau of Reclamation, since ]963 Navajo Dam has significantly altered flow of the San Juan River by typically storing spring peak flows and releasing water in summer, fall, and winter months resulting in an average decrease in spring peak flows of 45 percent, while approximately doubling winter base flows at the Bluff gauge in Utah. Similar comparisons can be made at the upstream gauges at Shiprock and Farmington, New Mexico. Significant depletions and redistribution of flows of the San Juan River also have occurred as a result of other major water development projects, including Navajo Indian Irrigation Project and the San Juan-Chama Project. None of these three projects have completed section 7 consultation under the Endangered Species Act. The Bureau requested formal consultation with the Service on July 30, 1991, for the operation of the Navajo Dam. These depletions, along with a number of other