WSP01392

• File Number: 8240.200.10.B
• Description: UCRBRIP - Riverine Fish Flow Investigations
• Basin: Colorado Mainstem
• Date: 6/1/2000
• Author: CDOW
• Title: Riverine Fish Flow Investigations 2000
• Water Supply Pro - Doc Type: Publication

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1995 filings were based on recommendations made by the U. S. Fish and Wildlife Service

(USFWS) in regard to recovery of endangered fish species [Modde and Smith (1995) and

Osmundson et al. (1995)]. In a more recent study Modde et al. (1999) used an infection point

method to assess minimum stream flow needs for Colorado pikeminnow (Ptychocheilus

lucius) on the Yampa River. Even though the intent of these studies was the same, to

determine stream flow requirements for endangered fish, the methods in each study were

different. The CWCB expressed a desire to have a more standardized approach for instream

flow filings and it is hope that recommendations using this approach will be acceptable to

agencies involved with endangered species recovery.

Study Objectives:

I). Model fish habitat availability on warm water sections of three rivers (Yampa,
Colorado and Dolores) using the established methods (Id models) and evaluate the
practically of using 2d flow models to quantify fish habitat.

2). Determine community structure, density and biomass for fish assemblages for
river reaches listed above.

3). Test for relationships between habitat availability and fish abundance.

4). Develop and validate methodologies that use I-D and 2-D flow models for the
Division of Wildlife to use for minimum in stream flow recommendations for the
warm water sections of the Yampa and Colorado rivers.

STUDY AREA

YamDa River

The study site located at River Mile (RM) 63 is referred to as the Sevens, since most

of this site is on the Sevens Ranch (Figure I). Between RM 59 and 85, most of the river
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