Laserfiche WebLink
<br />o <br />W <br />I-' <br />CO <br /> <br />PART III. HISTORY OF DEVELOPMENr <br /> <br />A. Acres Irrigated Prior to Colorado River <br />Storage Project Authorization <br /> <br />A study of the irrigated acreage in the Upper Basin shows that about <br />800,000 acres were irrigated by 1905. Irrigation development took place <br />gradually from the beginning of settlement about 1860, but was hastened <br />by the purchase of land from the Indians in 1873. Between 1905 and 1920 <br />the development of irrigated land continued at' a rapid pace, and by 1920 <br />nearly 1,400,000 acres were irrigated. Then the development leveled off <br />and there has been very little increase since that time. The 1929 and <br />1939 agriculture censuses show a little over 1,400,000 acres irrigated, <br />with the 1949 and 1959 censuses recording a little under that amount. <br /> <br />The lack of further increase in irrigated acreage in the Upper Basin <br />is ascribed to both physical and economic limitations in the availability <br />of water. By 1920 most of the lower cost and more easily constructed de- <br />velopments were in operation, and, although some new developments have <br />taken place since that time, they have been offset by other acreages go- <br />ing out of production. <br /> <br />A large acreage is irrigated in the Lower Basin below Imperial Dam, <br />and in the Gila River watershed. However, only the principal areas <br />above Imperial Darn are discussed in this report. studies of irrigated <br />acreages within the Lower Basin show about 12,000 acres irrigated in Ne-. <br />vada and 23,500 acres in utah, including 9,500 acres presently irrigated <br />in the Dixie project area. <br /> <br />, <br />Irrigation began in the Palo Verde area in 1879 and was expanded be- <br />tween 1905 and 1908 by construction of an intake structure and gravity <br />canal. A new diversion structure was completed in 1957 allowing the ir- <br />rigated acreage to be increased to about 83,000 acres in 1964. <br /> <br />Irrigation on the Colorado River Indian Reservation was first at- <br />tempted in 1870, but failure of the headgate structure resulted in flood- <br />ing sections of the. valley. other difficulties were encountered, and by <br />1936 only 5,000 acres were actually irrigated. With completion of a new <br />diversion structure in 1942 the acreage has steadily increased so that <br />about 32,000 acres were irrigated in 1964. <br /> <br />B. Depletions <br /> <br />During the period of record examined in detail in this report (1941- <br />1964), the average yearly consumptive use of water witnin tne Upper Basin <br />is estimated to be about 1,685,000 acre-feet. This is low compared with <br /> <br />10 <br /> <br />