BOARD02599

• Board Meeting Date: 11/23/1998
• Description: Colorado River Basin Issues - Glen Canyon Adaptive Management Program - Status Report - Letter from the Secretary of the Interior to Al Gore
• Board Meetings - Doc Type: Memo

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REPORT TO CONGRESS: OPERATIONS OF
GLEN CANYON DAM PURSUANT TO THE
GRAND CANYON PROTECTION ACT
OF 1992
(WATER YEARS 1997 AND 1998)

REPORT TO CONGRESS

Section 1804 (c)(2) of the Grand Canyon Protection Act of 1992 (GCPA) requires the
Secretary of the Interior (Secretary) to:

. . . transmit to the Congress and to the Governors of the Colorado River Basin
States a report, separate from and in addition to the report specified in section
602(b) of the Colorado River Basin Project Act of 1968 on the preceding year and
.the projected year operations undertaken pursuant to this Act.

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Therefore, this is the first Report to Congress since the Glen Canyon Dam Adaptive
Management Work Group was established in January 1997 and the operating criteria for Glen
Canyon Dam were put into place. The report focuses on Glen Canyon Dam operations and
activities pursuant to water years 1997 and 1998, Adaptive Management Program (AMP)
activities for water years 1997 and 1998, and activities of the Grand Canyon Monitoring and
Research Center (GCMRC) for water years 1997 and 1998.

HISTORY

The Colorado River Storage Project (CRSP) Act of 1956 authorized the construction,
operation, and maintenance of Glen Canyon Dam to regulate the flow of the Colorado River
for flood control; consumptive use, and the generation of hydroelectric power. Seven years
later, in 1963, Glen Canyon Dam was completed, making Lake Powell the key storage unit
for the CRSP. Flow releases from the dam were adjusted daily to respond to variances in
electrical demand.

At optimum operations, the generators at Glen Canyon Dam are capable of producing 1,296
megawatts of power. Water releases from the dam occur at 200-230 feet below the surface of
Lake Powell, which results in clear cold water with year-round temperatures of 410F to 45 of.
The recreation, irrigation, and hydropower benefits introduced to the southwest by Glen
Canyon Dam are extensive and continue to expand.

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Since the damming of the river in 1963, there has been only one flow release which
approached average pre-dam spring floods. In 1983, a combination of unanticipated
hydrologic events in the upper Colorado River Basin, combined with a lack of available
storage space in Lake Powell, resulted in emergency spillway releases from Glen Canyon