Reuse of Drainage Water for Irrigation: Results of Imperial Valley Study: I. Hypothesis, Experimental Procedures, and Cropping Results

An irrigation/cropping management strategy has been developed to facilitate the use of brackish waters for irrigation, with the goal of expanding the available water supply and minimizing the off-site pollution potential of drainage disposal. A field experiment conducted in the Imperial Valley of California to test the strategy has produced four years of cropping results. After seedling establishment, when the crops were in a sufficiently mature, salt-tolerant growth stage, brackish drainage water (Alamo River) was substituted for the normal water (Colorado River) to irrigate wheat and sugarbeets (in a successive crop rotation of wheat:sugarbeets:cantaloupes) and cotton (in a block rotation of cotton:cotton:wheat:alfalfa). A good stand was obtained under relatively low conditions of salinity by using Colorado River water for the preplant and early-season irrigations.