BOARD01466

• Board Meeting Date: 11/20/2000
• Description: ISF Section - Instream Flow Recommendations
• Board Meetings - Doc Type: Memo

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Introduction

Hanging Lake is a unique scenic lake and waterfall area, making it a popular recreation
destination. Located 10 miles east of Glenwood Springs (Figure I), approximately 80 to
100 thousand people visit Hanging Lake every year. The trail up to the lake from the
Colorado River follows Dead Horse Creek within a narrow canyon. The lirnestone
geology causes variations in the amount of water in the creek within the canyon. Several
springs can be seen along the trail. At the lake, the waterfalls that were created in the
limestone both above and below the lake allow various water dependent plants and
animals to populate the area. The area above the lake has little visitation and is
characterized by large waterfall, pool, and wetland complexes. The character of the.
watershed is dependent on the water flowing through it.

There are currently no instream water rights held for the water in the Dead Horse Creek
watershed. The Forest Service would like all in stream flow right to be held in order to
rnaintain the water in the streams for recreation, aesthetics, fish, wildlife, and water
dependent resources (Appendix A). In order to do this, it was necessary to understand
and quantify the hydrologic regime of the wlltershed.

Objective

To determine the amount of water available to support a claim for instream flows to
maintain the water in Dead Horse Creek botb above and below Hanging Lake and
Spouting Rock.
This was accomplished by:
I. measuring streamflow in tl1e basin above and below the lake from
August 1995 to July 1996.
2. observations of the hydrologic characteristics of the system.

Study Area

A. Description

Hanging Lake is within the Dead Horse Creek watershed (Figure 2). This watershed has
an area of 6,791 acres (10.61 square miles). Mean basin elevation is 9,347 feet, with a
mean basin precipitation of35 inches. Spouting Rock and Hanging Lake are on East
Dead Horse Creek. The Jake is at 7040 feet elevation and is approximately 0.25 surface
acres. East Dead Horse joins West Dead Horse Creek approximately 460 feet below
Hanging Lake to form Dead Horse Creek, tributary to the Colorado River.

The vegetation within the watershed is 61 % forested, 25% grasslands, 9% shrublands,
3% non-vegetated rockland, and 2% riparian. Riparian areas are shown in Figure 3. Due
to the unique combination of land type, vegetation, and water dependent ecosystems
present, the area above Hanging Lake is being considered for possible nomination into
the Forest Service Research Natural Area program. Appendix B and C present notes
from wildlife biologists and the Forest Ecologist. Appendix D is an excerpt from the

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