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<br />Distribution of Water Use
<br />A more complete description of water use in the South Platte River basin was compiled previously by
<br />Caulfield et al, (1987), The major characteristics of water use in the basin are provided in the following
<br />summary. Division I of the Colorado State Engineer's office administers over 542 major irrigation
<br />diversions, 4500 major direct flow rights, and 1200 major storage rights in the South Platte Basin, Water is
<br />used for a variety of purposes including irrigation, municipal, industriaVcommerciaJ, recreation, and
<br />environmental uses,
<br />Agricultural land use is distributed throughout the basin, Most of the agricultural land is cropland and
<br />pasture, with small areas designated as confined feeding operations, The cropland consists of 40% irrigated
<br />land and 60% cbyland farming, Most of the irrigated land is located within a triangle formed by the cities of
<br />Boulder, Fort Collins, and Greeley, and along the main stem of the South Platte River, Total irrigated
<br />acreage in the basin in 1992 was approximately 730,700 acres, based on county agriculture census data. The
<br />primary crops grown in the basin are corn for grain and silage, perennial forages, small grains, sugar beets,
<br />wheat, cby beans, sunflowers, and some vegetables, The types of irrigation practices used are flood, furrow,
<br />and sprinkler irrigation systems, Farming operations located adjacent to surface water supplies use primarily
<br />surface irrigation methods, although the use of sprinkler systems tapping the alluvial aquifer are becoming
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<br />more common.
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<br />Interstate Compact Considerations
<br />Use of South Platte River water is subject to the restrictions set forth in the South Platte Compact signed
<br />by Colorado and Nebraska in 1923, The compact stipulates that between October 15 and April I, Colorado
<br />has full use of all flow within its boundaries, except for one proposed canaI beginning near Ovid, and flowing
<br />into Nebraska. Between April I and October 15, Colorado can divl\rt water with a priority junior to June 14,
<br />1897 downstream of the Washington-Logan county line ouly if the mean daily flow at the interstate station at
<br />Julesburg is greater than 120 cfs, Colorado water rights senior to that date can continue to divert water if
<br />flows are less than 120 cfs,
<br />Average annual total flow leaving the state at Julesburg is 387,000 acre-feet (Ugland et al" 1994),
<br />During the month of August, flows leaving the state average 153 cfs, exceeding the compact requirement by
<br />ouly 33 cfs, In years when supplies are low, compact requirements often restrict the junior water rights on the
<br />river in late summer months, 1bis results in limited direct-flow diversion potential for all but the most senior
<br />users on the lower end of the system, In fact, most ditch systems on the lower end of the system with rights
<br />junior to the compact have been abandoned,
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