Shoring up a stream: Angling group spearheads project to benefit Knife River steelhead
On a sunny March morning, the Knife River comes hustling around a shaded bend and emerges into full sunlight. It is far above Lake Superior, the river's ultimate destination, at this point. This bend is several miles above the runs where steelhead anglers hope to hook powerful rainbows on their spring spawning runs.
This is where many steelhead — Lake Superior's migratory rainbows — come to spawn. These narrow upper reaches of the Knife and its tentacled tributaries are where baby steelhead spend the first year or two of their lives before down-migrating to the lake.
And this particular corner on the river bears all the signs of man's touches. An eroding clay bank has been reshaped and stabilized with mesh mats. The rooty stubs of Norway pines placed horizontally along the outside of the bend can be seen beneath a grassy floodplain. Elsewhere along the banks, sapling dogwoods, snowberry, red maples, red oaks and high-bush cranberry plantings reach for the sun.
All of those elements are part of a habitat project completed last summer along 2,200 feet of the upper Knife River, a cooperative project of the Lake Superior Steelhead Association — an angling group — along with the Minnesota Department of Natural Resources and several other agencies. The money came from state sales tax revenue through the Clean Water, Land and Legacy Amendment and the Lessard-Sams Outdoor Heritage Council. The improvements on that portion of the river represented $500,000 of an overall $1.4 million grant.
Kevin Bovee, secretary of the steelhead association, stands in the sun and watches the river make its turn.
"I've been with the club since '84 or '85," Bovee said. "This has the potential to be the best thing this club has ever done."
Jeff Tillma, a stream habitat specialist with the Minnesota DNR at Grand Rapids, worked closely with the association and its cooperators on the project.
"It's a two-pronged approach," Tillma said. "One of biggest things is reducing the sediment load that's going into river. You had that big, steep eroding bank causing excessive sediment and erosion. The (steelhead) club has its own second set of values — trying to improve fish habitat in a localized reach. They're looking at creating holding cover for steelhead fry and smolts (juvenile fish) and deeper pools for overwinter habitat."
One of the goals of the project was to create habitat that might hold juvenile steelhead in the river for two years instead of just one, said Craig Wilson, who until recently was president of the Lake Superior Steelhead Association.
When young steelhead leave the river after just one year, they are less likely to survive in Lake Superior and return as adults to spawn.
"We really assessed the river and found the best project we could do," Wilson said. "We're looking at landscape issues, water quality issues and trout habitat."
Better flow, cooler water
By reshaping the clay bank and using "root wads" — the bases of red pines — to create a horizontal floodplain at the base of the bank, the river's dynamics have been changed. Now the channel is narrower and the current somewhat faster. Rocks strategically placed in the river help divert the river's energy from the outside bank to the center.
"The stabilized stream banks eliminate sediment discharge into the river but also provide a floodplain for flood waters to crest over the stream bank and dissipate the current's energy," LSSA's Wilson said. "The replanted shrubs and trees restore an overhead canopy to shade the stream. This rehabilitation ultimately maintains a cooler water flow in our critical trout-rearing areas."
If a river is carrying too much sediment, it isn't good for trout, said the DNR's Deserae Hendrickson, Duluth area fisheries supervisor. Especially where the river slows, the sediment tends to drop out.
"It covers up good habitat, filling in the spaces in the riffles where fish need to spawn," Hendrickson said. "It can cover up eggs laid in the gravel and suffocate them."
The steelhead association's project also narrowed the river's channel in this reach. It had become too wide as the outside bank had eroded. When a river widens, its velocity drops and sediment is deposited.
"Having that correct channel dimension is just as important as stopping additional sediment deposition to the channel," Hendrickson said.
The scouring of that clay bank in high-water periods might have dated back many decades to a time when the area was originally logged, Hendrickson said. Without trees to moderate and slow run-off, the river likely ran higher, chewing away at its banks.
This project is one of several habitat projects on North Shore streams in recent years, and more are in the planning stages. Minnesota Trout Unlimited and its partners have done recent projects on the Sucker, Stewart and Little Stewart rivers and Kimball Creek. More TU projects are planned for the Stewart, Split Rock, Kadunce and Little Devil Track rivers, among others. Some of those projects benefit steelhead, and some benefit brook trout.
Private property borders the Knife River where last summer's habitat work was done, and landowners agreed to allow the project, which meant moving heavy equipment to the river.
"We couldn't have done it without their acceptance," Bovee said.
The DNR has secured easements on long stretches of the upper Knife River that allow anglers to fish those waters using proper access.
The availability of funding from the Lessard-Sams Outdoor Heritage Council, under the umbrella of the Legacy Amendment, is critical to doing these kinds of projects, the DNR's Tillma said.
"It's a good example of how Outdoor Heritage funds can be spent to improve habitat," Tillman said. "(Steelhead association members) have a long-range plan. They're looking at other reaches they want to do. They're working well with us."