Trout Brook Stream Restoration
Project Overview
Meet Trout Brook
Trout Brook is a restored cold water trout stream located just west of the St. Croix River. Through ecological restoration and partnership, Trout Brook was revitalized, and is now home to native Brook Trout.
Degraded habitat
Trout Brook is a cold water stream located just west of the St. Croix River that flows through parts of Afton State Park and Afton Alps Ski resort. South Washington Watershed District identified Trout Brook as a site for restoration to improve water quality.
Since the mid-1800s, the Trout Brook subwatershed has experienced significant changes to surrounding land use and slope, leading to increased erosion and sediment in the stream. The channel has also changed. Historic aerial photos show that some areas of Trout Brook’s meandering stream once spanned the width of the valley.
But as land use demands changed, so did the shape of Trout Brook, and from 1938 (left) to 1953 (right), the width of the channel decreased. By 2013, assessments conducted by the MnDNR concluded that Trout Brook produced about 351 tons of sediment per year. However, estimations showed that by restoring Trout Brook, sediment could be reduced by 75% to 85%.
With the construction of the Afton Alps ski area, the channel was constrained to a straightened ditch to allow for the construction of parking areas, buildings, and ski runs. As a result, the channel had little habitat value and worsened flooding and erosion within the ski area property and downstream State Park.
Restoration
The goal of restoration is to improve aquatic habitat and reduce sediment and nutrient discharge into downstream Lake St. Croix and St. Croix River. To achieve this, SWWD and its partners implemented a comprehensive strategy to restore the subwatershed.
Improvements were identified and prioritized by the Washington Conservation District as part of their Lake St. Croix Top50P! project. SWWD addressed 3 of the priority sites using funds from the State’s Clean Water Fund, and began planning the restoration of 3,780 linear feet of Trout Brook.
Re-meandering
The centerpiece of the Trout Brook restoration project is the re-meandered channel and floodplain created within the Afton Alps property. In 2019, the channel was rerouted from a straightened alignment that ran through the Afton Alps parking lot, back to its historic alignment.
- Remeandering of Trout Brook stream
Construction
Construction of the new channel began. The new construction includes a full 100-year floodplain and pool, riffle, and run habitat segment to promote fisheries reestablishment.
Downstream construction
Downstream, the lower segment of Trout Brook was also reconstructed to improve the aquatic ecosystem with pools, runs, and riffles to promote fish reestablishment.
Flow Restored
Flow from upstream Trout Brook was connected to the restored lower segment. The final connection marks the end of the major restoration efforts of Trout Brook. Management of surrounding vegetation and monitoring is ongoing.
Trout Stocked
In partnership with the MnDNR, roughly 2,000 native Brook Trout were released to replenish the stream. The trout are a heritage strain of native brook trout, called MN Driftless. This strain of fish have been cultivated by the MnDNR by gathering the eggs and milt of the few remaining native populations of brook trout in Minnesota.
Power in partnership
The restoration of Trout Brook is a shining example of partnership between public, private, and non-government organizations. Restoration was made possible through extensive collaborative efforts, and the grant support of our partners including, Vail Corporation, Afton State Park, Great River Greening, Lower St. Croix Watershed Partnership, Lessard-Sams Outdoor Heritage Council, and the Minnesota Department of Natural Resources and Board of Water and Soil Resources.
Kyle Axtell
Staff Contact
Questions? Reach out to Kyle Axtell, Planning & Projects Program Manager, at Kyle.Axtell@swwdmn.gov or call 651.728.6124.