WSP06927

• File Number: 8220.101.09B
• Description: Glen Canyon Dam/Lake Powell
• State: AZ
• Basin: Colorado Mainstem
• Date: 7/1/1990
• Author: BOR
• Title: GCD EIS Summary of "Long List" of Alternatives
• Water Supply Pro - Doc Type: EIS

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Long Term criteria

1. Release will be 8.23 to 20.5 maf per year with full pool
elevation of Lake Powell of 3700 ft. during less than full
pool years 8.23 maf is relesed unless spills are anticipated
and releases must be increased.

2. Temperature of releases from 46-54 degrees F and existing
water quality and sediment load (minimal).

3. Keep "Annual Operating Criteria" active with Lake Powell
targeted to fill each July and contain 22.6 maf on January 1
of each year.

4. Releases to meet monthly targets, then releases to fulfill
seasonal variations.

5. stocking of exotic fish by AGF, no user limit in the Glen
Canyon National Recreation Area, existing limits on
recreation use in Grand canyon National Park.

6. Avoid spills, but operations between less than 1,000 cfs up
to 90,000+ cfs.

7. Probability of floods 1 in 20 years.

Institutional Constraints Common To All Alternatives

1. continue normal maintenance functions.

2. Maintain Colorado River Forecasting Service for monthly
forecasts of expected inflow.

3. No determination of operating criteria by the Secretary of.
the Interior for 602(a) of P.L. 90-537 storage. These
criteria are for the coordinated long-range operations of
the Upper Basin reservoirs and Lake Mead.

4. continue to use SCADA system to coordinate CRSP facilities.

5. Keep general Power Marketing criteria.

6. Maintain definitions of compact Point, Upper and Lower
Basins, and keep the two objectives; water storage for
regulation and irrigation and beneficial consumptive uses
and satisfy the 8.23 maf requirements above other project
purposes.

Based on these assumptions the following No Action Alternative
was prepared and presented at the July 10, 1990 meeting.

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