AZ vs. CA:11 California Exhibits, Vol. XI; Nos. 1001-1011; 1101-1109; 1201-1251; 1301-13431301-1343

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CALIFORNIA DEFENDANTS Exhibit No. 1207 Identification: July 12, 1957 Admitted Extract From United States Department of Agriculture, Bulletin No. 1026, Irrigation in Northern Colorado (1922). (PP. 24-25) THE CONSUMPTIVE DUTY. The water actually consumed, or the consumptive duty, may be arrived at by considering in addition the water which passes into the South Platte River from the Cache la Poudre River, Lone Tree Creek, and various canal wasteways dumping into the South Platte or Crow Creek. In 1916 the available supply exclusive of seepage return was 336,000 acre-feet, and 79,000 acre-feet passed out of the valley. The net consumption of 257,000 acre-feet on the 218,000 acres irrigated that year gives a duty of 1.18 acre-feet per acre. In 1917 the supply was 608,000 acre-feet, and 309,0007 acre-feet passed into the South Platte. The net consumption of 299,000 acre-feet on the 225,000 acres irrigated that year gives a duty of 1.33 acre-feet per acre. As the water supply during 1916 was slightly below normal and in 1917 was far above normal, it seems reasonable to assume that the average consumptive duty is approximately 1.25 acre-feet per acre.8 7Partly estimated. 8This calculation does not take into account return seepage from Poudre Valley land going- directly into the South Platte. Taking this into account would reduce slightly the quantity of water actually consumed.