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<br />operations will be allowed to exceed elevation 240 feet. Through August 2002, approximately <br />105,460 acre-feet had been over delivered to Mexico in CY 2002. <br /> <br />Laguna Reservoir is a regulating storage facility located approximately 7 river miles downstream of <br />Senator Wash. Operational objectives are similar to those for Senator Wash Reservoir. The storage <br />capability of Laguna Reservoir has diminished from about 1,500 acre-feet to about 600 acre-feet due <br />to sediment accumulation and vegetation growth. Sediment accumulation in the reservoir has <br />occurred primarily due to flood releases that occurred in 1983 and 1984, and flood control or space <br />building releases that occurred between 1985 and 1988 and from 1997 through 1999. Dredging of <br />the Laguna Reservoir to increase its storage capability to contain sluicing operations at Imperial <br />Dam is scheduled to begin in CY 2004. <br /> <br />Imperial Dam <br /> <br />Imperial Dam is the last diversion dam on the Colorado River for United States water users. From <br />the head works at Imperial Dam the diversions of flows for American water users and Mexico occur <br />into the All American Canal on the California side, and into the Gila Gravity Main Canal on the <br />Arizona side of the dam. These diversions supply all the irrigation districts in the Yuma area, in <br />Wellton-Mohawk, in the Imperial and Coachella Valleys, and through Pilot Knob to NIB to the <br />Mexicali Valley in Mexico. The diversions also supply much of the domestic and industrial water <br />needs in the Yuma area. <br /> <br />Yuma Desalting Plant <br /> <br />The Yuma Desalting Plant (YDP) was not operated in CY 2002 and is in a ready reserve status. In <br />calendar year 2001 the amount of water discharged through the Main Outlet Drain was 107,910 <br />acre-feet. The U.S. recognizes that it has an obligation to replace, as appropriate, the bypass flows. <br />Reclamation is preparing a report for Congress that explores options for replacement of the bypass <br />flows from Wellton-Mohawk, including options that would not require operation of the Yuma <br />Desalting Plant. Operation of the YDP would affect the Cienega de Santa Clara, a marsh of <br />approximately 10,000 acres that is a protected environmental area in Mexico. <br /> <br />The Main Outlet Drain and Main Outlet Drain Extension (MODE) requires minor repair work each <br />year, and a short section ofthe MODE near the confluence with the Gila River that was damaged <br />during the 1993 Gila River flood still needs to be repaired. However, seepage from the drain is less <br />than one percent of the ground water flow in the area and is not significantly affecting the quality of <br />the ground water or the Colorado River water. Minor repair work accomplished each year consists of <br />replacing isolated broken concrete panels and cleaning debris from the drainage system. In March <br />2002, some drainage water was spilled from the MODE to the Colorado River to accommodate <br />panel replacement along much of the MODE. All Wellton-Mohawk Irrigation & Drainage District <br />drainage flows are expected to be contained in the MODE for the rest of CY 2002 to prevent <br />increasing the salinity of the Colorado River arriving at the Northerly International Boundary (NIB) <br />with Mexico. <br /> <br />Measures that are being taken to ensure that the salinity differential requirements at NIB will be met <br />include reducing drainage pumping in the South Gila Valley in areas with more than adequate depths <br /> <br />December 13, 2002 <br /> <br />19 <br /> <br />