BOARD02166

• Board Meeting Date: 9/21/1998
• Description: ISF Section - New Appropriations - Notice to Appropriate Instream Flow Water Rights in Water Division 1
• Board Meetings - Doc Type: Memo

Natural Environment Studies

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The Colorado Division of Wildlife (CD OW) and CDPOR have conducted field surveys of the
fishery resources on these streams and have found that a natural environment can be preserved on
each of these streams. To quantify the resources and to evaluate instream flow requirements, the
CDOW and CDPOR collected biologic and hydraulic data which were analyzed by the CDOW and
Board staffs. Based on the results of these analyses, the CDOW and CDPOR prepared
recommendations of the amount of water necessary to preserve the natural environment to a
reasonable degree for each of the streams on the attached list of Instream Flow Recommendations.

Water Availability Studies

The CWCB staffhas conducted an evaluation of water availability for these streams. To detennine
the amount of water physically available for the Board's appropriations, the staff analyzed available
USGS gage records, available streamflow models, and/or utilized appropriate standard methods to
develop a hydro graph of mean/median montWy flows for each recommendation. The staff also
relied upon the flow measurements made as part of the field survey as an indicator of the amount
of water physically available in each stream and analyzed the water rights tabulation for each stream
and consulted with the Division Engineer's Office to identity any potential water availability
problems. Based upon its analysis, the staff has determined that water is available for appropriation
on each stream to preserve the natural environment to a reasonable degree without limiting or .
foreclosing the exercise of valid existing rights.

8T AFF RECOMMENDA nON

For each stream listed in the attached List ofISF Recommendations, the staff recommends that
the Board:

(I) Detennine. pursuant to section 37-92-102(3), CRS, and based upon the recommendation
of the CD OW and CDPOR, a review of the data and other information presented by the
staff, in this memo and orally, and the staff's recommendation for instream flow
appropriations on the streams identified; that:

(a) A natural environment does exist on each stream;
(b) Water is available in each stream for appropriation;
( c) The natural environment will be preserved to a reasonable degree by the water
available for the recommended appropriations;
(d) There is a natural environment that can be preserved to a reasonable degree with
the recommended water rights, if granted; and
(e) Such natural environment can exist without material injury to water rights.

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