OCR Text |
Show Depletion of the Colorado River as a result of this Unit is estimated at 315,000 acre- feet per year. The increase in salt concentration at Hoover Dam would be 28.0 mg/ 1. Using the EPA value, this increase would cost downstream water users $ 1,159,200 per year in decreased yields. Minimum Development^^ ( a) Description The minimum development of Ute Indian Unit would satisfy the Indian Deferral Agreement of September 20, 1965, by providing a full irrigation water supply for 19,840 acres of Group 5 Indian lands by the year 2005. Assuming Uintah Unit would be constructed and serve 7,820 acres of the Group 5 lands, all of the 27,660 acres of Group 5 Indian lands considered irrigable in the Uinta Basin and possessing a recognized water right would then be served. The Unit would develop 67,000 acre- feet of water annually. Design data for features of this Unit have not been completed in sufficient detail to allow adequate evaluation of environmental impacts. Considerable engineering work has yet to be accomplished in the way of materials investigations, damsite drilling and feasibility design. However, a sketch map of the Unit showing major features is shown in Figure C- 24. Tentative complexes are described below. JL. Leland Bench Complex Leland Bench lands would be served a full irrigation water supply by pumping water directly from Green River. A total area of 15,180 acres, representing essentially the entire irrigable area of the bench would be served in exchange for Tawanta Flats, Mud Springs, Rock Creek Bottoms and Ouray Area Group 5 Indian lands. There would be 16 miles of earth lined canals, eight pumping plants, ranging in size from 300 to 30 c. f. s.; and three equalizing reservoirs, ranging in capacity from 600 acre- feet to 1,900 acre- feet. Leland Bench is located in the more arid part of the Uinta Basin and has a low growing sagebrush and shadscale cover. The bench is presently used for winter sheep grazing. With a net diversion requirement of 3.4 acre- feet per acre, there would be 436 |