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001228 CHAPTER II RESOURCES AND USES . Project Use of Water Project diversions from the Gunnison River through the Gunnison Tunnel averaged about 296,000 acre-feet from April through September over the 1952-1970 period. The diversions are limited by the capacity of the tunnel which isnominally 1,000 c.f.s. but has actually been capable of carrying only about 960 c.f.s. for many years. Generally, the tunnel diversions are reduced to those amounts needed to supplement supplies to project canals available from the Uncompahgre River and its tributaries. These reductions usually occur near the beginning and end of the irrigation season and during the Uncompahgre River snow melt runoff period. The tunnel is normally operated only during the April through October period. Water diverted through the tunnel is released to South Canal laterals, to West Canal and to the Uncompahgre River. Other project canals divert natural flows of the Uncompahgre River and South Canal releases to that stream as well as flows of small tributaries of the Uncompahgre River intercepted by the canals. . Irrigation season diversions of project canals from the Uncom- pahgre River and its tributaries plus releases from South Canal to its laterals and to West Canal avera~ed 500,800 acre-feet over the 1952-1970 period. Of this amount, 346,800 acre-feet was delivered to project farms and the remainder was lost or wasted from project canals. Much of water losses and wastes from the higher canals and lands is rediverted by lower canals and is included in the project water supply. For the 83,800 acres of irrigated land, the annual diversion of 500,800 acre-feet of water diverted represents an average of nearly 6.0 acre-feet per acre of irrigated land. However, with the high rate of canal and lateral seepage losses and administra- tive waste, the farm delivery is approximately 4.1 acre-feet per acre. The available project irrigation water supply is more than ample during most of the irrigation season. During the periods of peak water demands, however, the lands eKperience some shortages due to insufficient supply and restricted capacities of the distri- bution facilities. The capacity limitations occur principally in the West Canal and the Montrose and Delta Canal systems. An average of about 41,700 acre-feet of water is diverted into project canals and laterals during the non-irrigation season for the livestock use. Municipal and Domestic Water . The cities, towns and some of the rural communities have had domestic water systems for a number of years and the Tri-County Water Conservancy District is now planning and constructing systems for most of the remaining populated areas of the Uncompahgre River Valley. Some of the existing systems will be incorporated into or interconnected with the Tri-County system. .31