Lending a helping hand to Afton’s Trout Brook

South Washington Watershed District partners with Great River Greening and Vail Resorts

A coldwater stream flows through the hills of Afton Alps and Afton State Park, bringing life to a valley in the woods. Over the past 150 years, Trout Brook has weathered the rise and fall of logging in region, decades of farming, and several manmade alterations designed to make way for parking lots, roads, buildings, and ski slopes. This year, South Washington Watershed District is working with Great River Greening and Vail Resorts to complete a large-scale restoration project designed to return tiny Trout Brook back to good health.

The landscape in Afton and Denmark Township features deeply carved valleys amidst steep wooded hills. The same hills that make Afton Alps a great place to ski also create unique habitats. Groundwater flows out of the bedrock and into Trout Brook year round and the stream helps to sustain native brook trout, turtles and frogs, migratory birds, and even fox and badgers. After passing through Afton Alps, Trout Brook flows through Afton State Park to the St. Croix River.bridge-sign-1

When European-American settlers first mapped the area in 1848, the Trout Brook stream corridor was entirely forested, with prairie found only near the headwaters (located just east of Manning Ave. today). Over the next 100 years, however, settlers from Germany and Sweden converted much of the landscape to farm fields. Eventually, in 1960, three local farm families combined 300 acres of land to create Afton Alps. Construction began in 1960 and the ski hill opened on December 21, 1963 with 37 guests in attendance. Five years later, the state purchased adjoining land, which eventually became Afton State Park. Today, the park includes 1,702 acres of land along the river with trails and hike-in camping.maps

Over the years, government and non-profit partners have worked to restore habitat and reduce runoff pollution within the St. Croix River corridor and along its tributaries. As part of a larger study conducted in 2013, Washington Conservation District identified several potential projects to improve water quality in both the St. Croix River and Trout Brook, including within Afton Alps. With funding from the Minnesota Clean Water Fund and Outdoor Heritage Fund, South Washington Watershed District and Great River Greening were able to move forward on the Trout Brook restoration effort this year. Vail Resorts, which owns and operates Afton Alps, has provided support as well.

WCD staff collecting water quality sample from Trout Brook
Washington Conservation District staff collecting water quality sample from Trout Brook.

The Trout Brook stream restoration will help to keep sediment and nutrients out of the St. Croix River and will also create a passage for trout and other fish to swim upstream and down at different times of the year when they are feeding, overwintering, and laying eggs. The stream was re-routed from an artificial channel back to its natural, meandering course and several additional features were added to improve habitat and reduce erosion. The “wiggles” in the stream create different types of habitat that fish need: deep pools with slow-moving water; shallow riffles with fast, turbulent water running over rocks; and runs with deep, fast water and little or no turbulence. Wood logs will help to anchor the stream bank.

Project partners also re-created the natural floodplain that once existed along the banks of Trout Brook. Now, when it floods, water will be able to flow outside the stream channel so that sediment settles out along the banks of the stream instead of in the center. That way, the fertile soil can nourish plants along the water’s edge instead of burying fish spawning areas in the stream. Water flowing downstream to the St. Croix River will also be clearer and carry less nutrients. Culverts near the parking lot entrance will also be replaced so that water can flow continuously.meander

The Afton Alps project will create ideal habitat for the stream’s namesake native brook trout, as well as smaller fish including sculpin, white suckers, creek chubs, brook sticklebacks, and pearl dace. Already, biological surveys have found a healthy array of aquatic invertebrates to serve as a food source for these fish – larval insects such as mayflies, dragonflies, caddisflies, stoneflies, and craneflies. In addition, the stream corridor will continue to support reptiles, amphibians, mammals and birds.

Visitors can see and learn about the Trout Brook restoration on Oct. 10-13, during Afton Alps “Fall into Winter” Fair. The weekend’s events will include a ski and snowboard swap sale, as well as family friendly events:

  • Friday, Oct. 11, 4-9pm: sale, s’mores, chairlift rides, nature walk and food trucks
  • Saturday, Oct. 12, 11am-5pm: sale, chairlift rides, beer sampling, hay rides, kids inflatable jumper, and pumpkin painting
  • Sunday, Oct. 13, 12-5pm: sale, chairlift rides, hay rides, kids inflatable jumper, and pumpkin painting.

Learn more about the Afton Alps “Fall into Winter” Fair.

Learn more about the Trout Brook restoration.