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2376 and the Tribal Council. By 1977, about 25,000 cropped acres were being scheduled. Technically in a demonstration phase, the program has been well received by irrigation operators and the Tribal Council intends to continue it into the future. The attainment of higher onfarm efficiency depends on quick, efficient application of water to the field, and on accurate measure- ment of water delivered to each turnout. These requirements are not adequately met on the Reservation. Other obstacles to higher effi- ciency may be lack of level or uniform slope in fields, unlined farm ditches, excessive length of irrigation runs, and irrigation methods unsuited to soil type. In order to achieve the full benefit of sche- duling, onfarm improvement is required in some areas. Measurement of water delivered at each farm turnout also needs to be upgraded. Approximately half the turnouts permit the ditch- rider to set the delivery rate with a Penn Vane meter, but at the remaining turnouts the delivery rate is estimated by inches of gate opening. The irrigator does not have the opportunity to monitor the delivery rate to determine exactly how much water he is using. Some kind of metering device at each turnout would result in better water usage. Coordination of Development In order for water use efficiency measures to be in effect when needed for agricultural expansion, it will be necessary to implement improvement programs in the near future. Federal programs with potential, other than the Colorado River Water Quality Improvement Program, include those administered by the Bureau of Indian Affairs and the U. S. Department of Agriculture. The Bureau of Indian Affairs has a construction program on the Reservation under which new laterals are built and older laterals are lined as needs dictate and as funds permit. At present, BIA envisions an improvement program under which unlined canals with the greatest seepage losses will be lined and new lined laterals will be constructed in the southern part of the Reservation in the next 5 years. Thereafter, more existing unlined laterals will be lined in a sequence determined by their relative seepage losses. It is estimated that the cost of lining the unlined portions of the existing irrigation 27