AZ vs. CA:07 California Exhibits, Vol. VII; Nos. 326-370

page 58

58 PROBLEMS OF IMPERIAL VALLEY AND VICINITY. new concrete structure has been installed at this point sufficient in capacity to irrigate the entire valley. The structure is controlled by wooden emergency gates, with steel stem screw-lifting devices. Ordinarily it is controlled by flashboards, over which the water enters the canal, permitting the skimming process. As the main current of the river strikes the Blythe heading it is free from silting up above the intake. Two and one-half miles below the intake is sluiceway No. 1, and at mile 4 is sluiceway No. 2, which are large wooden structures. The skimming process is repeated at these points over flashboard into the canal, and the silt is sluiced out into the river. Excess water is run to these points for this purpose. At 7| miles below the intake are located the controlling gates of the three submains, at the lower end of the main canal proper. The engineer in charge, Mr. Yost, states that the canals are sufficient in capacity for the irrigation of the entire valley on condition of proper cleaning. The main levee as constructed at present extends from the head of the valley to the county line near the lower end of the valley, a length of 28£ miles. The section of the levee is: Crown 12 feet, river slope 3:1, land slope 2:1, average height 10 feet. A borrow pit has been constructed continuously on the land side, with a berm of 50 feet between the pit and the levee. This borrow pit is intended as a shallow drain and has been fairly successful for this purpose, though deep drains are planned some distance back from the levee; 3,500 feet only of the levee have been riprapped. Two miles of railroad are constructed on the levee and 3 miles leading from the levee to the quarry. There are several cross levees extending from the main levee out into the valley. The area protected by levees at present is said by the engineer in charge to be 70,000 acres, which is also the area under the present constructed canal system. The area irrigated in the present season (1920) is approximately 35,000 acres. The shares of water stock issued by the company represent water sufficient for 1 acre to the share. To the present date, October 20. 1920, 40,700 shares have been sold. These shares are valued at $35 per share. IRRIGATION PLAN. The Palo Verde project is entirely a gravity system. The water is diverted direct from the river at the Blythe intake, as above described, without a diversion dam. There is no plan on the part of the management for the construction of a dam at this point, first, for the reason that it is not needed, as at practically all times there is sufficient head against the intake for the required diversion, and in the^second place for the reason that there is no dam site at the head of the Palo Verde Valley. As stated previously, there is no physical reason why the river should not leave the Blythe heading and go to the east, as there is a wide, flat valley at this point. This, however, has never occurred in the history of the project, though it does not necessarily follow that it will not occur in trie future. Such a possibility is realized by the present management, and plans are made to riprap the opposite bank in case it should become necessary.