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through 1986, irrigation scheduling information was furnished for about 49,000 acres of crops each year. However, the irrigation scheduling program was completely dropped by WMIDD in 1994 as there were less than 4,000 acres still participating. WMIDD decided that with the few acres participating, the benefits no longer warranted the costs of continuing the program. Reclamation provided technical expertise, training, and funding for the program. WMIDD provided one district employee and office facilities at the district. Reclamation funding for the IMS program ended in 1987. Research and Demonstration Program-Six projects were funded under this program, which provided information on cultural practices, equipment, and economic considerations that could lead to improved irrigation efficiencies. Projects included monitoring soil salinity, studying emitter clogging in trickle irrigation systems, managing pressure irrigation systems for citrus crops, managing dead-level irrigation, automating surface irrigation, and evaluating alternative irrigation systems. All projects were completed by 1980. Education and Information Program-The objectives of this program, conducted by the University of Arizona Cooperative Extension Service, were: (1) to provide liaison among the various irrigation efficiency programs and (2) to educate and encourage growers to adopt recommended techniques and practices. Program information was provided through publications, television, and radio. With grower cooperation, field trials were held to demonstrate water management benefits, and field days were conducted on topics such as automated irrigation systems, irrigation scheduling and efficiency, and crop consumptive use. Results-Before the program was initiated, WMIDD irrigation efficiency was 56 percent. While the program was active, overall WMIDD irrigation efficiencies exceeded 72 percent, the level estimated to reduce irrigation drainage to 108,000 acre-feet per year. An overall peak irrigation efficiency of 77 percent was reached in 1985, and irrigation drainage dropped from 220,000 acre-feet to a low of 118,500 acre-feet per year. While the program demonstrated an overall positive effect, a cause-and-effect relationship for individual measures has never been established. Status-All permanent measures implemented by the WMIDD are still in use, although the Federal program has been discontinued. Total crop acres have remained relatively stable since the early 1970's because more acreage is double-cropped than when the program was initiated. More recent irrigation efficiency levels and return flow levels for 1990 through 1992 are as follows: Year Irrigation efficiency (percent) 59 58.4 71.5 Irrigation efficiency adjusted for rain (percent) 54.1 54.1 60.4 Return flow (acre-feet) 138,407 144,931 116,200 1990 1991 1992 47