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PART VII COLORADO RIVER SALINITY CONTROL PROGRAM e actual results and minimize investment if certain features are not proved effective. By staging portions of projects, however, the trade- offs for m~nimizing risk may involve higher final costs, delays in proj- ect completion, potential project reductions due to funding constraints or changes in plans, and loss of the support of local water users. Recent experience in monitoring the effects of seepage control and col- lection wells indicates that conclusive evidence is highly subject to masking by normal hydrologic events, and moni toring for several years may be necessary to show defini tive results. It is important to note that the intensive onsite monitoring programs, reservoir effec ts, and ion constituent studies have served to increase the knowledge of the salinity problem and significantly reduce the risk and uncertainty of control efforts. e Some of the Basin States have raised water rights issues over disposal of collected saline water in evaporation ponds. Under Colorado water law, such a control system would not meet the requirements for "beneficial use" in granting a water right. Moreover, the disposal of large quantities of water in ponds requires large land areas and high investment costs in land preparation and liners to prevent leakage. The only strategy that appears to satisfy these concerns is to deliver collected saline water for beneficial use by private industry or for energy development. This strategy, however, increases our dependence on the uncertainties of energy development and the water supply plans of private industry. The Colorado River Salinity Control Forum is addressing this water rights issue on a case-by-case bqsis by an ad hoc committee. 1. Title I Program Title I of the Colorado River Basin Control Act of 1974 (Public Law 93-320) provided the means to comply with the United States obligations to Mexico which included as a major feature a desalting plant and brine discharge canal. These facilities will enable the United States to deliver water to Mexico having an average salinity no greater than US ppm .:!:. 30 ppm (United States count) over the annual average salinity of the Colorado River water at Imperial Dam. a. Coachella Canal Lining To assist in meeting the salinity control objectives of Title I, the Secretary was authorized to construct a concrete-lined canal or to line the unlined initial 49 miles of the Coachella Canal. The act required that a repayment contract be executed with the Coachella Valley County Water District for partial repayment of the cost of the work. e The Coachella Canal originates as a diversion from the All-American Canal at a turnout point near the Mexican border and runs in a generally northwestern direction for a distance of 123 miles. It provides an irrigation water supply for lands now totaling about 67,000 acres in the Coachella Valley. The Coachella Valley County Water 65