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. <") ,~ f"\ 4' ':>U"l. District. HYdrology studies were completed before these revised acreage figures were available; however, the change is too small to \olarrant revision of the hydrologic analyses. In evaluating requirements, the classified acreage was reduced by six per cent to allow for non-productive land in farm roads, ditches, etc. The acreage figures presented in the following paragraphs are the productive acres used in the hydrology studies. TIle requirements for ten small ditches were not computed and not included in the operation study because the pum~ing analysis indicated that sufficient water is pumped under these ditches to provide a full su~ply for the class 1, 2 and 3 lands. This conclusion would not preclude the sale of water to these ten ditches, however. The productive area historically irrigated under the 23 ditches in the conservancy district included l3l+,593 acres of class 1, 2 and 3 land and 21,908 acres of class 6w land. There are also 19,591 productive acres of irrigable non-irrigated land under the 23 ditches. The 23 major ditches in the proposed service area historically diverted 346,300 acre-feet per year from DIe river and existing reservoirs. Of this amount, 164,200 acre-feet became available at the farm. In addition, 86,900 acre-feet per year \olere pumped at the farm. The combined sources provided a supply of 1.60 acre-feet per acre at the farm headgate. . On lands under the 23 ditches, the average annual farm headgate requirement for supplemental water was fOillld to be 71,500 acre-feet on the 134,593 acres of class 1, 2, and 3 land historically irrigated, plus l+1,700 acre-feet on the 19,591 acres of irrigable non-irrigated class 1, 2, and 3 land. Table 1 is a summary of the historic water utilization. The average annual shortage does not give an adequate description of the requirements since there is a large variation from year to year. For the 1947 through 1961 period, the diversion requirement for project water at the river varied from a low of about 87,000 acre-feet in 1951 to a high of about 310,000 acre-feet in 1955, while the average annual requirement for project \olater was 182,800 acre-feet. Shortages are experienced in every year primarily because of the lack of storage on some of the ditch systems. . The operation studies reflected in this appendix were accomplished \olith three discrepancies in the computations of re- quirements for project water; (a) the demand for irrigable non-irrigated lands under the Fort Morgan, Upper Platte and Beaver and Deuel and Snyder canals show small errors, (b) the supply to the Julesburg Highline canal \olas neglected in the historic \olater utilization study of the Julesburg system and (c) class 6w lands were not given a supply equal to the historically irrigated class 1, 2 and 3 lands in the studies. 5