BOARD01940

• Board Meeting Date: 11/23/1998
• Description: ISF Section - New Appropriations - Notice to Appropriate Instream Flow Water Rights in Water Division 5
• Board Meetings - Doc Type: Memo

Natural Environment Studies

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The CDOW and CWCB 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 CWCB collected biologic and
hydraulic data that were analyzed by the CDOW and Board staffs. Based on the results of these
analyses, the CDOW 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 determine
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 hydrograph of mean monthly 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, analyzed the water rights tabulation for each stream and
consulted with the Division Engineer's Office to identify any potential water availability problems.
Based upon its analysis, the staffhas 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. .

STAFF RECOMMENDATION

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

(I) Determine. pursuant to section 37-92-102(3), CRS, and based upon the recommendation
of the CDOW and the 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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