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summer water needs. This drawdown will also correspond with maintenance at both Davis and Parker powerplants which is scheduled for September through February. During 2003, Lake Mohave will continue to be operated under the constraints as described in the Biological and Conference Opinion on Lower Colorado River Operations and Maintenance. Reclamation, as provided in the Interim Surplus Guidelines Record of Decision, will continue these existing operations in Lake Mohave that benefit native fish through the effective period of the Interim Surplus Guidelines and will explore additional ways to provide benefits to native fish. The normal filling pattern of these two reservoirs coincides well with the fishery spawning period. Since lake elevations will be typical of previous years, normal conditions are expected for boating and other recreational uses. Reclamation is the lead agency in the Native Fish Work Group, a multi-agency group of scientists attempting to augment the ageing stock of the endangered razorback sucker in Lake Mohave. Larval suckers are captured by hand in and around spawning areas in late winter and early spring for rearing at Willow Beach Fish Hatchery below Hoover Dam. The following year, one year old suckers are placed into predator-free, lake-side backwaters for rearing through the spring and summer. When the lake is normally drawn down during the fall, these fish are harvested from these rearing areas and then released to the lake. The suckers grow very quickly, usually exceeding ten inches in length by September. Senator Wash and Laguna Reservoirs Operations at Senator Wash Reservoir allow regulation of water deliveries to United States and Mexican water users downstream ofImperial Dam. The reservoir is utilized as an off-stream storage facility to meet downstream water demands and to conserve water for future uses in the United States and the scheduled uses of Mexico in accordance with the Treaty obligation. Senator Wash Reservoir is the only major storage facility below Parker Dam. Senator Wash Dam is located approximately 142 river miles downstream of Parker Dam. Operational objectives are to store excess flows from the river which have been caused by water user cutbacks and side wash inflows due to rain. Stored waters are utilized to meet irrigation, recreational, and Treaty demands. Elevation restrictions on Senator Wash Reservoir reduce the flexibility of water storage in the lower reaches ofthe river. Since August of 1992, a restriction at elevation 240.0 feet, mean sea level, at Senator Wash Reservoir was put in place. This was due to potential piping at West Squaw Lake Dike and Senator Wash Dam. After removing a rock tallus pile and replacing it with a filter blanket at West Squaw Lake dike during the first part of CY 2000, a reservoir fill test was started September 15 and concluded on October 19, 2000. The test had to be stopped due to piping concerns at West Squaw Lake Dike. During most of CY 2000, Senator Wash was not available to regulate river flows and excess flows to Mexico exceeded 300,000 acre-feet for the year. Since the fill test in CY 2000, a new elevation restriction at 235 feet was put in place, and excess flows to Mexico in CY 2001 dropped to about 200,000 acre-feet. In CY 2002 a new filter blanket was placed at West Squaw Lake Dike, additional instrumentation was put in place and another fill test was conducted from April through July 7, 2002. Senator Wash was not available for river regulation essentially from the first ofCY 2002 until July 7, 2002. Due to the success of this fill test the elevation restriction was raised back to elevation 240 feet on July 8, 2002 with some operational restrictions and monitoring requirements. It is likely that Reclamation will allow Senator Wash operations to range between elevations 242 to 245 feet. However, a review of the CY 2002 test fill data will be required before December 13,2002 18