8128

• UCREFRP Catalog Number: 8128
• Author: U.S. Bureau of Reclamation.
• Title: Operation of Glen Canyon Dam\
• USFW Year: 1995.
• Copyright Material: NO

Description of Alternatives
financial exception criteria relate to Western's ability to demonstrate that
unused generation capacity is available to meet firm (guaranteed) contract
commitments at times when nonfinn thermal energy is being used to meet
those commitments. Under interim operations, operational limits can be
exceeded for financial reasons up to 3 percent of the time (22 hours) in any
consecutive 30-day period, with no carryover.
Actually exceeding operating criteria for financial reasons is unlikely.
While Westem's customers have benefited from having financial exception
criteria available during interim operations, Western has not had to exceed
operating criteria for financial reasons. If financial exception criteria are
part of the selected alternative, the availability of capacity and energy
would be maintained, and costs to customers would be expected to
increase at a slower rate.
Western may have to change the way power is marketed in the region as a
result of changed operations at Glen Canyon Dam. Western currently is
preparing an EIS to evaluate systemwide power marketing and allocations.
PERMITS AND REGULATORY APPROVALS
No permits or regulatory approvals would be necessary immediately to
implement any of the alternatives. Depending on the results of long-term
monitoring and research under adaptive management, permits under
sections 402 and 404 of the Clean Water Act may be needed in the future.
ALTERNATIVES ELIMINATED FROM DETAILED ANALYSIS
During the scoping process, including formulation of alternatives, various
alternatives and concepts were considered. Some were determined not
reasonable for detailed analysis, as explained below.
Run-of-the-River Alternative
Conclusion
Many comments received during the scoping process expressed a desire
that the darn be operated to mimic predam conditions in Grand Canyon.
The EIS team responded by formulating the Run-of-the-River Alternative,
with the goal of achieving predam conditions through operational
changes, sediment augmentation, and selective withdrawal.
A return to a seasonal streamflow pattern emulating the magnitude of
historic spring flows would be very destructive to downstream resources
unless a large-scale, long-term sediment augmentation program were
added. However, sediment augmentation would cause an increase in
Glen Canyon Dam EIS Summary 33