Middle Fork Project 5

Erosion from this streambank adjacent to a recreational trail contributes 26.2 tons/year of sediment to the river, the single largest source of sediment entering the Middle Fork.




Middle Fork West Fork Gallatin River (Aspen Groves & Antler Ridge Open Space)

Estimated Cost


Background: The Middle Fork of the West Fork of the Gallatin River (Middle Fork) is one of six tributaries of the Gallatin River that does not meet state water quality standards. Resource concerns include erosion, vegetation loss, and pollutants (i.e. sediment, nutrients, and E. Coli) which impact aquatic life, wildlife habitat, and recreational uses. In order to address these resource concerns, the Task Force worked with Trout Unlimited to develop five restoration projects aimed to improve water quality, habitat conditions, and build climate change resiliency. The first Middle Fork Project was completed in October 2021.

Project Description: Project 5 will be the second river restoration project implemented on the Middle Fork to bolster wetland and riparian conditions, improve fish habitat, and enhance water storage capacity. Taking cues from beavers, natural-water-storage projects help us adapt to climate change by slowing spring runoff and soaking the soil sponge. This project is part of our proactive work to improve water quality and increase the availability of water by making the most of Big Sky’s winter snowpack.

Existing Conditions: The project is adjacent to the winter and summer recreational trail system maintained by Lone Mountain Ranch. Historically, the stream channel was located within a meadow rather than its current location along the recreational trail and a large eroding streambank. Additionally, the channel is a continuous riffle lacking diverse in-stream habitat. Riparian health in the project area is defined as moderate-fair, meaning mature vegetation exists along 20% or less of the stream and the width of riparian vegetation is generally 10 feet or less.

Proposed Improvements: 
The primary goals are to reconnect the steam with the floodplain, enhance wetland/riparian vegetation, eliminate sediment loading, raise the water table throughout the meadow, and improve trail conditions. These goals will be met by achieving the following objectives:

  • Restore the channel into the center of the meadow
  • Relocate the channel away from the eroding streambank and revegetate the hillside
  • Enhance wetland features with woody debris jams and artificial beaver dams
  • Relocate trail off of eroding streambank and relocate/replace trail bridge

Project Status: WGM Group has been hired to design the project and fundraising is underway.

View the 90% design here
View the restoration plan here

Private Landowners:
Antler Ridge Homeowners Association
Aspen Grove Homeowners Association

Natural beaver dam downstream of project site.

Thank you to our incredible donors

The work we do would be impossible without your support.

Project Partners

Trout Unlimited

Project Funders

Trout Unlimited
Gallatin Invasive Species Alliance
Gallatin Invasive Species Alliance

The Montana Watershed Coordination Council’s Watershed Fund Grant is made possible via funding from the Montana Department of Environmental Quality and the U.S. Environmental Protection Agency.