WSP12329

• File Number: 822.600.10
• Description: Colorado River Annual Operating Plan - Annual Reports
• Basin: Colorado Mainstem
• Date: 1/1/1995
• Author: USDOI/BOR
• Title: Annual Operating Plan
• Water Supply Pro - Doc Type: Annual Report

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Lake Mead

The nonnal condition wilJ govern the operation of Lake Mead and all reasonable beneficial
consumptive needs of Colorado River mainstream users will be met in calendar year 1995,
The outlook for lowest and highest monthly releases under the most probable inflow
conditions for calendar year 1995 will be 771 MCM (.625 MAF) and 1,337 MCM
(1.084 MAF) respectively.

Lake Mead is expected to finish calendar year 1994 at 24,604 MCM (19.945 MAF), which
is 77 percent of conservation capacity and approximately 12.8 m (42 feet) below the top of
the conservation pool at 371.9 m (1220 feet) and 31,922 MCM (25.877 MAp), Reservoir
storage elevation is projected to rise to 359,7 m (1180 feet) in February 1995, which is
78 percent of conservation capacity or 24,938 MCM (20.216 MAF) and approximately
12.2 m (40 feet) below the top of the conservation pool. Storage elevation is projected to
decline to 356.6 m (1170 feet) in June 1995, which is 73 percent of conservation capacity or
23.284 MCM (18.875 MAF) and approximately 15.2 m (50 feet) below the top of the
conservation pool. No flood control releases are anticipated in calendar year 1995 under any
inflow scenario.

Drawdown during the peak largemouth bass spawning period in April and May is planned to
be near the limits of decline recommended in the July 1982 final report of a five year study
by the Arizona Game and Fish Department and the Nevada Department of Wildlife. In
future years. as Lake Mead refills and flood control releases are again required by the
Hoover Dam Flood Control Regulations, consideration will be given to making these releases
over the fall and winter months to avoid high flow releases during the January through July
runoff season. This distribution of water reduces the chance of bypassing hYdroelectnTIc
powerplants below Hoover Dam and avoids the adverse impacts of higher flood control
releases on fish and wildlife. recreation, water quality, and river stabilizati<;m.

Lakes Mohave and Havasu

Mohave and Havasu Reservoirs are scheduled to be drawn down in the fall and winter
months to provide storage space for local stonn runoff and will be filled in the spring to
meet higher summer water needs. This drawdown will also correspond with maintenance at
both Davis and Parker Powerplants which is scheduled for September through February.
The nonnal filling pattern of these two reservoirs coincides well with the fishery spawning

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