Projects

Upper French Gulch Fish Passage

Project Description

BHWC and partners are working to restore fish passage and stream connectivity to 1.7 miles of pristine stream that is currently devoid of fish in the upper reaches of French Gulch, a headwater tributary of the Big Hole River.

This project will address a major stream impairment and is part of a suite of projects in the French Creek watershed to address basin-wide water quality, habitat issues, and native fishery restoration. The primary goal of the project is to provide passage for native fish to the upper reaches of the French Creek drainage. This requires replacing the existing cascade and culvert barrier with a sinuous, step-pool system. Another goal is restoration of two eroding streambanks downstream of the cascade through revegetation and application of bioengineering techniques using both hand crews and heavy equipment.

The fish barrier on French Gulch was created by historic placer mining activities that took place from the 1860s to the 1930s). Placer mining was an extremely destructive practice, and while there has been little mining activity in the area in the last 100 years, impacts from historic mining are still evident on the landscape. In French Gulch, the valley floor was extensively mined from one side to the other, effectively lowering its elevation by about 30 ft. The stream was moved to the west side of the valley and trapped there by the careful placement of a nearly vertical boulder-wall known as the Chinese Wall. At the head of this wall, the stream drops off in a steep cascade of water to the elevation of the old mining area. This cascade is so steep (and lacks pool habitat) that it effectively prevents upstream fish passage. The cascade is blocking access to about 1.7 miles of habitat to native species including Westslope Cutthroat trout and Arctic grayling. Access to critical, cold-water refugia and spawning habitat such as those available in the headwaters of French Gulch is important for the survival of these sensitive native fish.