WSP03164

• Author: USFWS
• Title: Management Plan for Endangered Fishes in the Yampa River Basin - Volume II -Appendices - USFWS - 09-01-2004

032526

August 23, 2000

page I

TECHNICAL MEMORANDUM

SUBJECT: Green River Basin Plan
Wyoming Depletions in the Little Snake River Basin

PREPARED BY: States West Water Resources Corporation
Revision made August 23, 2000 by Wyoming State Engineer's Office

Introduction

The Little Snake River is not directly tributary to the Green River in Wyoming. It is tributary to the
Yampa River which ultimately flows into the Green in Dinosaur National Monument in northwestern
Colorado. A programmatic biological opinion will be prepared to address the potential effects of the
"Management Plan for Recovery of the Endangered Fishes of the Yampa River Basin and Continuation
of Existing Human Water Uses and Future Water Development." The purpose of the Management Plan
is to allow for the use and future development ofYampa River Valley water resources and to protect and
promote the recovery of the four endangered fish species which reside in the Upper Colorado River
Basin. The development of the Management Plan is occurring as an activity of the ongoing Recovery
Implementation Program for Endangered fish Species in the Upper Colorado River Basin, which has
been ongoing since 1988. The State of Wyoming is a participant in the Recovery Program and is
participating in the development of the Management Plan. This memorandum documents current
estimates of depletions due to activities in Wyoming, and presents estimates of depletions out to year
2045.

The average annual water yield from the Little Snake River Basin in total is 428,000 acre-feet (Hawkins
and O'Brien, 1997). Sources of depletions in Wyoming include irrigated agriculture, environmental
use, municipal use and transbasin diversions for the City of Cheyenne. As of 1994, total Wyoming
depletions in the basin were estimated at 39,900 acre-feet annually (Bums & McDonnell, 1999,
Appendix D).

No current depletions are explicitly associated with either industrial or domestic uses. Industrial uses
are small and generally included within municipal demand estimates. Domestic uses are also small. To
the extent they are comprised of individual small wells serving residential populations, domestic uses
will not significantly affect surface water flows.

Therefore, determination of current and future demands consists of updating municipal, agricultural and
City of Cheyenne depletions, and projecting them out to year 2045. Additional depletions are estimated
for future environmental and industrial uses.

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Appendix C - Technical Memoranda from Colorado and Wyoming

C-5