IMPERIAL VALLEY, CALIFORNIA, AUGUST 2009: A sprinkler system sprays crops with water from an irrigation canal set in an agricultural area which traditionally uses water from the Colorado river distributed through a series of canals and irrigation channels, Imperial Valley, 6 August 2009. This tank also uses a tail back recovery system whereby runoff water is collected and pumped back up to the farm for recycling. The yellow pipe in this image is the runoff water pump. Sprinklers are used in conjunction with drip irrigation. Drip irrigation leads to salt build up around the plants and sprinklers are used albeit less often to disperse the salinity which is is a byproduct of all Colorado river water. The Imperial Valley is a desert area which controversially uses three quarters of Californias allocated river water for agricultural purposes. The agricultural techniques have traditionally been flood and furrow which experts claim waste vast quanties of precious water. Imperial Valley farmers are looking at alternative techniques through which to conserve water supply. (Photo by Brent Stirton/Reportage for Getty Images.)