| OCR Text |
Show PROBLEMS OF IMPERIAL. VALLEY AND VICINITY 51 includes 14 miles of flume, 1.6 miles of tunnel, and over 2 miles of siphon, with 220-580 foot head, with most of the expensive work concentrated in the 20-mile section from the head works to the point where irrigable land starts. The only work done on this unit is the benching for the flume. Duty of vxiter.-A diversion of 2 acre-feet per acre annually is expected to care for the needs of this project. Water supply.-The water supply for the Nelson ditch uni^ is Beaver Creek, whose total estimated annual flow of 50,000 acre-feet is subject to prior rights for 7,000 acres under the Gurley ditch. The relation of irrigation demand and supply for an average year under the Nelson ditch system is as follows:. Water supply, Nelson ditch unit. [Acre-feet.] Month. Beaver Creek flow. Required for prior rights. Available for Nelson ditch. Demands for Nelson ditch. Required storage. April... 11,000 18,000 12,000 3,000 1,000 500 1,100 2,800 4,200 2,800 2,100 • l,.000 9,900 15,200 7,800 200 1,600 4,000 6,000 4,000 l 3,000 1,400 Mav....... June........ July... 3,800 3,000 1,400 August. September.. October___ March...... 4,500 Total 50,000 14,000 8,200 Storage capacity of 8,200 acre-feet would be required for seasonal regulation in an average year, which would be increased to 12,000 acre-feet to provide for abnormal years and for desirable hold-over. This storage is supposed to be available in Beaver Park. For the San Miguel Canal unit the relative supply and demand are as follows: ' Water supply, San Miguel Canal unit. [Acre-feet.] Month. Available supply. San Miguel River. Saltada Creek. Beaver Creek.i Clay and Horsefly creeks." Total. Prior rights Nucla colony 10,000 acres. Residue for San Miguel ¦project. Demand for San Miguel project. April....... May........ June....... July........ August..... September. Total 13,800 42,000 50,400 27,900 14,300 11,800 700 3,500 1,400 500 200 200 3,000 8,000 4,000 1,000 500 500 6,000 9,000 3,000 1,000 500 500 23,500 62,500 58,800 30,400 15,500 13,000 2,000 5,000 7,500 5,000 3,800 1,700 21,500 57,500 51,300 25,400 11,700 11,300 8,000 20,OjOO 30,000 20,000 15,000 7,000 160,200 6,500 17,000 20,000 203,700 25,000 178,700 100,000 Unused by proposed projects above. There would apparently be some shortage in August of any average year and larger shortages than this table shows would occur in many years but the expense for necessary storage to obviate them would probably not be warranted. |
