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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6. Increase water temperatures in the Colorado River to favor
the native fish by altering flow patterns and by taking warm
water from the top of Lake Powell instead of drawing cold
water as is presently done.

7. Reintroduce native species now extinct in the Grand canyon.

8. Required or conduct a special study of the impact that human
use of the Colorado River has on the humpback chub.

9. Striped bass are coming up river from Lake Mead and
threatening both native fish and trout. striped bass must
be controlled and prevented from moving upstream.

Trout Pishery

10. This element would address the requirements for trout
spawning, minimize stranding, and enhance trout
recruitment.

11. Plant more trout to compensate for those lost in spawning.

12. Plant new varieties of fish that are more tolerant of river
fluctuations.

13. Place more restrictions on fishing during trout spawning
season.

14. Access to trout fishery during low flows could be improved
by dredging, channeling etc.

15. Spawning pools could be improved by changes in operation of
Glen Canyon Dam to reduce stranding.

RIPARIAN VEGETATION HABITAT

1. Elements to mitigate impacts to riparian vegetation should
consider flood reduction, native fishes, sediment and
fisheries.

2. Native plants have been replaced by introduced plants such
as substitution of willow trees for tamarisk trees. The
native vegetation should be given preference in the
management of the Grand Canyon.

3. Hikers and boaters have damaged the riparian vegetation
independent of power production of any kind. Restrictions
on numbers and activities are necessary to protect
vegetation.

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