This post was written by Big Sky Watershed Corps member Lacey Gunther as a part of a series reviewing the stops along the 2019 Missouri Headwaters Watershed Tour. Lacey shares more about our stop at the Poindexter Slough restoration project in the Beaverhead Watershed.
Poindexter Slough is a special place just 4 minutes outside of Dillon, MT. It’s one of the only publicly accessible spring-fed creeks in Montana, offering a variety of fishing and hunting opportunities, and anglers frequently catch brown trout over 18 inches.
Although Poindexter Slough was traditionally a major draw for anglers, seeing over 4,000 per year, in the 2000’s those numbers started to drop. The famous brown trout fishery was producing smaller trout, and angler numbers dwindled to just 610. The local economy could feel the effects as direct expenditures in Beaverhead County decreased.
The problem? Sediment.
As an old channel of the Beaverhead River, Poindexter is larger than typical creeks. It has the capacity to hold 500 cubic feet per second (cfs), but lately, flows have been much smaller (30-50 cfs) due to changing irrigation practices. A switch from flood to sprinkler irrigation lessened groundwater inputs, and the slough became increasingly supplemented with sediment-heavy water from the Beaverhead River.
As flows became lower and slower, large amounts of fine sediment began to deposit in the slough. Spring flows weren’t enough to flush it out. Pools filled in, fish habitat declined, and the number of large brown trout dropped considerably. Landowners and outfitters alike were concerned. That’s when the Beaverhead Watershed Committee (BWC) stepped up. One of BWC’s mottos is “working together for the river we share.” The Committee supports inclusive community projects, local leadership, and a strong commitment to sustaining the landscape.
Using everything from bake sales to grants to private donations, BWC raised over $1 million dollars for the project. They collaborated with local stakeholders, Montana FWP, Confluence Consulting, and the Dillon Canal Company. Starting in 2015, the project began with modifications to irrigation infrastructure, stream channel narrowing to 200 cfs capacity, sediment dredging, and the creation of pools and riffles to enhance fish habitat. The BWC and partners developed a management plan to allow for occasional “flushing flows” through Poindexter to mimic natural spring runoff and keep the sediment moving. When funding for the project ran low, local contractors continued to work on Poindexter on their own dime – an indication of the strength of local support for the project.
Over the course of 4 years, 4.73 miles of Poindexter Slough were restored. The proportion of brown trout greater than 18 inches is larger than it’s been in the last 15 to 20 years. Locals can run and walk through the Poindexter trails, fish for an hour or two after work, or bring their children to play with fuzzy cattails found in wetland areas. The renewal of Poindexter Slough as a community resource also serves as a reminder of the power of the Watershed Approach to conservation.
It’s clear that this community values its watershed. This is good because the work isn’t over. Although flushing flows to remove sediment and maintain Poindexter have been implemented successfully for the last 2 years, changing climatic conditions and future droughts may have negative impacts. Upcoming BWC restoration projects will have an important role to play, and everyone will need to stay engaged.
Want to learn more about Poindexter Slough or support future BWC projects? Visit http://www.beaverheadwatershed.org/