BOARD00117 ‎(2)‎

• Board Meeting Date: 1/24/2007
• Description: WSP Section - Glen Canyon Adaptive Management Program - Long-Term Experimental Plan for Future Operation of Glen Canyon Dam EIS
• Board Meetings - Doc Type: Memo

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January 23-24, 2007 Board Meeting
Agenda Item 19
Page 3 of4

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humpback chub and sediment resources insofar as possible and maintaining that balance.
Alternatives should:

. Include a range of flows with variable, patterns, and timing, but remain
consistent with the Compacts and "Law of the River;"
. Include non-flow experiments, such as non-native fish removal, the
development ofrefugia and ultimately a stocking program;
. Be based upon credible science;
. Maximize hydropower capacity and flexibility to the extent possible
. Address the cultural resource issues

The experiments in the plan should be of adequate duration to allow for a
determination of appropriate actions needed to sustain, and where possible, improve the
resources as provided for in the Grand Canyon Protection Act and to achieve the balance
or resources and benefits shown in the 1995 EIS.

In addition to commenting on the scope ofthe alternatives, AMWG fOlwarded
four options that it had developed to the Secretary of the Interior for consideration in the
EIS illustrating a range of flow and non-flow experiments that AMWG had debated. The
flow variations and management actions are illustrated on the attached spreadsheet.

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The big ticket item here will be installation of a "temperature control devise" or
TCD. The Department of Interior and the vast majority ofthe AMWG see the TCD as an
essential management tool. While it appears a TCD could help improve conditions for
the endangered humpback chub, it may also provide conditions that are beneficial to non-
native predators and parasites. Construction of a TCD is a huge investment that needs to
be taken in small steps if it goes fOlWard, which it most likely will.

There is always considerable debate regarding the need and usefulness of a Beach
Habitat Building Flows (BHBF), or releases from Glen Canyon Dam that bypass the
power plant and generally result in flows of around 40,000 to 45,000 cfs. During this
past fall, the Grand Canyon Monitoring and Research Center (GCMRC) scientists
reported that a significant amount of sediment was discharged into the Colorado River by
the Paria River and also from the Little Colorado River as a result ofthe monsoonal
storms in the region. Without a BHBF, they maintain this sediment is likely to slowly
migrate down the main channel of the river without increasing the size of beaches or
improving backwater habitats. The GCMRC would like to conduct a short-term "spike-
flow" release to move as much of this sediment as possible up onto beaches and develop
or refresh backwaters along the river through the Grand Canyon.

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Because, the opportunity to conduct BHBF's is infrequent, there is always
discussion on where the available funding for this experiment would come from. In
addition, analysis of the data collected from previous BHBF's, the last of which occurred
in 2004, has been slow to occur and a concern for the Glen Canyon Adaptive
Management Program. The long-term plan is virtually certain to include BHBF's and a