8106

• UCREFRP Catalog Number: 8106
• Author: Anderson, R. M.
• Title: Riverine Fish-Flow Investigations.
• USFW Year: 1998.
• USFW - Doc Type: Fort Collins, Colorado.
• Copyright Material: NO

The data and methodology used on the Yampa River provide a strong description

of habitat/flow relationships and may have widespread application for minimum flow

recommendations in other warm water fish communities in western Colorado. The IFIM

data collected for habitat availability for Colorado squawfish is also presented. As

suitability curves for other native fish are developed, habitat availability (weighted usable

area) derived from IFIM sites on the Yampa will be compared to subsequent maps made

from other methodologies.

Study Area
DESCRIPTION OF RIVER STRATA

The study area includes warm water reaches between the lower 59 and 135 miles

of the Yampa River, from Cross Mountain to the town of Craig Colorado (Figure 1).

Miller (1982) stratified the warm water portion of the Yampa River into 8 strata as a

function of valley configuration. Strata one, two, three and four are located below Cross

Mountain and six, seven and eight are above.

Stratum 6 begins at RM 58.5 ends at RM 88.0 and includes the communities of

Sunbeam and Maybell. The Yampa River in this stratum meanders in a wide valley

floor, is low gradient and has a high percentage of sandy substrates. Most of the

floodplain is grazed and is adjacent to irrigated agricultural land. Only a small

percentage of the river bank is stabilized by shrubby vegetation. The Maybell gage is

located near the upper edge of this stratum at RM 85.8.

Stratum 7 is from RM 88.0 to 91.6, the length of Juniper Canyon. The river in

Juniper Canyon is confined by narrow canyon walls and is without a flood plain. The

Maybell diversion dam (a structure oflarge boulders across the river) and headgate are

located in this reach at RM 89.2. The river below the diversion dam has reduced flows

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