WSP06984

• File Number: 8220.101.10
• Description: Colorado River-Water Projects-Glen Canyon Dam/Lake Powel-Glen Canyon Adaptive Management
• Basin: Colorado Mainstem
• Water Division: 5
• Date: 7/27/1994
• Title: Western Area Power Administration Replacement Resource Methods Report-Grand Canyon Protection Act of 1992
• Water Supply Pro - Doc Type: Report/Study

'. .

The Glen Canyon Darn EIS was initiated in 1989 to evaluate impacts of
Glen Canyon Darn operations on downstream resources of the Colorado
River, The draft Glen Canyon Darn EIS, published by Reclamation in
January 1994, presents a range of long-term operational alternatives for
the dam. The Glen Canyon Dam EIS is mandated by the GCP Act to be
completed no later than 2 years after the date of enactment of the Act,
or October 1994.

Long-term operating criteria will be established based on the findings,
conclusions, and recommendations made in the Glen Canyon Darn EIS and the
audit performed by the Comptroller General on the costs and benefits of
management policies. A Reasonable and Prudent Alternative, presented in
a U.S. Fish and Wildlife Service Biological Opinion on operations of
Glen Canyon Dam, may also be incorporated into the long-term operating
criteria.

The amount of marketable resource lost at Glen Canyon Dam will be a
function of the long-term operating criteria selected and operational
changes made in response to conclusions emerging from research and the
long-term monitoring results. Estimates of the amount of hydropower
resource available at Glen Canyon Dam will become better defined as the
darn operations are revised.

Identifying feasible methods of replacing the power will require
assessment by existing firm power customers of both the magnitude and
timing of the lost resource at Glen Canyon Dam. Western's firm power
customers will influence whether Western will replace any or all of the
lost Glen Canyon Dam resource. Customers' decisions concerning
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