WSP13009

• File Number: 8282.600.10.B
• Description: 2005 Annual Operating Plan
• Basin: Colorado Mainstem
• Author: USDOI/BOR
• Title: 2005 Annual Operating Plan for Colorado River System Reservoirs
• Water Supply Pro - Doc Type: Operating Principles/Plan

(343 meters) at the end of July 2004 with 13.924 maf (17,146 mcm) in storage, 54 percent of
capacity.

The total release from Lake Mead through Hoover Dam during water year 2004 Was 9.635 maf
(1l,885mcm). C alendaryear2004totalreleaseisprojectedtobe 9.340 maf(1l,521 mcm).
Consumptive use from La1::e Mead during calendar year 2004 diverted through the Robert Griffith
. Water Project is projected to be 0.293 maf (361 mcm).

Under the most probable inflow conditions during water year 2005, Lake Mead will be at its
maximum elevation ofl,127.61 feet (344 meters) at the end of October 2004 and will decline during
the water year to reach its minimum elevation of 1,11 0.34 feet (338 meters) at the end ofJuly 2005.
Releases from Lake Mead for water year 2005 are projected to be 9.277 maf(11,443 mcm). Forthe
2005 calendar year, total releases are projected to be 9.358 maf (11,543 mcm). For the purpose of
projections, estimated releases are based on the Normal condition as the criterion governing the
operation of Lake Mead. No flood control releases would be required during water year 2005 under
any of the three inflow sc<::narios.

The Interim Surplus Guid<::lines ROD included ESA conservation measures. One such conservation
measure specified in Article X(4)(l) includes provisions for spawning razorback suckers in Lake
Mead. Reclamation continues to provide funding and support for the ongoing Lake Mead Razorback
Sucker study. The focus ofthe study has been on locating populations of razorbacks in Lake Mead,
documenting use and availability of spawning areas at various water elevations, continuing ageing
studies, and confirming recruitment events. No changes in operations were made in water year 2004
to provide rising spring water surface elevations for spawning razorback suckers as there were no
storage equalization releases or Beach/Habitat Building Flows during this timeframe. Based on the
anticipated operation of Lake Powell for water year 2005, no changes in operations to provide rising
elevations in Lake Mead are expected in the spring of2005.

l,akes Mohave and Havasu

At the begirining of water year 2004, Lake Mohave was at:an elevation of640.95 feet (195.4 meters),
with an active storage of 1.643 maf(2,027 mcm). The water level of Lake Mohave was regulated
between elevation 634 feet (193.24 meters) and 645 feet ( 196. 06 meters) throughout the water year,
ending at an elevation of 639.54 feet (194.9 meters) with 1.605 maf(1,980 mcm) in storage. The
total release from Lake Mohave through Davis Dam for water year 2004 was 9.43 maf(11 ,632 mcm)
for downstream water us(~ requirements. Calendar year 2004 total release is projected to be 9.16 maf
(ll,300 mcm).

For water year 2005, Davis Dam is expected to release: 9.00 maf (11,101 mcm). For the 2005
calendar year, releases are projected to be 9.08 maf(ll,206 mcm). The water level in Lake Mohave
will be regulated between an elevation of630 feet (192.02 meters) and 645 feet (196.06 meters).

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