WSP09216

• File Number: 8220.105
• Description: Colorado River-Water Projects-Navajo
• State: CO
• Basin: Colorado Mainstem
• Water Division: 5
• Date: 6/1/2000
• Author: BOR
• Title: Re-Operation of Navajo Dam-Navajo Reservoir Operations-Environmental Impact Statement Update
• Water Supply Pro - Doc Type: Publication

Page 3

Navajo Reservoir Operations EIS Updatc

June 2000

Effects of 500 cfs Flows on the
San Juan River Trout Fishery

Reclamation has l.:ontracted \\,ith the ;..,.e\\
\1exico Cooperative Fish and Wildlife RcseJ.rch
Unit at :\"ew .'.Iexico State LniversilY in las
Cruces to evaluate the elfeers winter nows of
500 cfs haw on the health of the San Juan River
trout tisher.' immedi::nelv below ~avajo Rescr-
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vOir.

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San Juan ny fisherman after the big one

For purposes of this study. nov.:s will rcmain at
500 cfs from October 2000 through ~Iarch ~OO I.
The same 4 month period. but with nows of
150 cfs. was used in a 19Q6-97 study of tish
health and conditions. The results of the October
2000 through ~larch 2001 research \\ill allow a
comparison of the two ditTerent How levels.

EIS Alternatives (Potentiai Actions)

The dr::l.ft EIS \\ill consider the following
possible altc-mati\cs for operating the d3m and
reservoir to implement the San Juan River Basin
Recovery Implementation Program's now
recommendations.

1. :-';0 Action

, FIOl..... recommendations with 250 cfs. (mini-
mum n:lcase.) - 5.000 cfs (maximum reh:ase)

3. .\loditied now recommendations with 500 cfs
(minimum release) - 5.000 cfs (ma.:ximum release)

4. .\toditied now recommendations with ~50 cfs
(minimum winter release). 400 cIs (minimum
summer release) - 5.000 cfs (maximum release)

5. \10ditied now recommendations with 150 cfs
(minimum release). 6.000 cfs (maximum release)

6. .\Ioditied now recommendations with 500 cfs
(minimum winter rdease) - 6.000 cfs (ma:'\imum
rekase)

.. cubic feel per s.:cond
... all releases fO b.: made from the dam

Rt.'c1amalion plans to identify a preferrcd alterna-
tive based on its ability to meet rCl.:ommended
nows for endangered tish and consideration of
environmental. economic. technical and other
factors. Based on public and agency comments
received during the draft EIS review process. the
preferred alternative mayor may not be the final
alternative selected.

The draft EIS will present the predicted etTects of
the alternatives on the human environment in
comparative foml. pro\'iding a clear basis for
choice among the options for [he decision maker
and the public. As a reminder. Reclamation plans
to ha\'e a draft EIS rr:ady for public re\'iev.' and
comm~nt in October 2000 (see EIS Time line).

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