For nearly four decades Jim and Cindy DeRuyter have enjoyed their peaceful Andover home with the Rum River in their backyard, a scenic amenity that offers quick access to smallmouth bass fishing and canoeing.
But over the years, the retired couple has watched the river creep onto their land. They estimate the river has engulfed at least 4 feet of their property while uprooting plenty of trees and sending them downstream.
To prevent further erosion, Anoka County is carrying on bank stabilization projects to protect the Rum and its recreational uses from the effects of development. Work with homeowners like the DeRuyters kicked off in 2014, and now the county, along with the Anoka Conservation District and partnering agencies, is planning a $1.7 million project to stabilize banks on mostly public land.
“The river is a lot wider than it used to be,” Cindy DeRuyter said on a recent afternoon down at the riverbank, inspecting deer tracks and checking on the bank stabilization work the county has completed in recent years.
Erosion on the Rum in Anoka County is happening at a significantly higher rate than in the upstream counties of Isanti and Mille Lacs because of the growing population and residential development downstream, said Jeff Perry, director of Anoka County Parks. It’s threatening water quality, wildlife and riverbank habitat — and conditions will worsen if left untreated, he said.
“The Rum River is truly a special river, not only to the people of Anoka County, but to the metropolitan region to have a connection with nature along a very scenic river,” Perry said. “It’s a resource I believe that is second to none in Anoka County for sure, if not the metropolitan area.”
Eighty areas along the Rum, amounting to a stretch of more than 7 of its 26 miles in Anoka County, are eroding from increased flow and precipitation. Conservation district officials have surveyed the river to identify moderate to severe sites of erosion and are collaborating with the county to develop a multiyear plan to block erosion.
Anoka County recently secured $185,000 from the Minnesota Department of Natural Resources (DNR) to start work on public land this fall, as well as $952,000 from the Lessard-Sams Outdoor Heritage Fund. The county is contributing a $100,000 match to the state funding, making a total of $442,000 in matching funds over the next five years.
Anoka County also is seeking $440,000 from the Clean Water Fund, a sales tax-based program through the Clean Water, Land and Legacy Amendment that voters approved in 2008.
“Since COVID-19 has hit, sales tax revenue have gone down dramatically, which will likely impact how much money will be available,” Perry said. “There will be implications for that moving forward until the economy gets up and running again.”
Stabilizing the Rum
The Rum River is one of six state-designated Wild and Scenic Rivers, as well as one of 35 Minnesota State Water Trails, and it’s known for its abundant smallmouth bass.
“There’s some older white pines that are probably over 100 years old that still remain on the river. From the waterfowl to the bald eagles to the shorebirds, songbirds, it’s a special piece of habitat,” Perry said. “So it’s definitely one worth taking good care of and preserving for future generations.”
Three Anoka County parks line the river in St. Francis, Ramsey and Anoka, along with canoeing campsites and public boat launches. The Rum is popular for tubing, and some homeowners keep pontoons at the ready on private docks.
Erosion on the Rum causes more sediment to flow into the Mississippi, which smothers spawning habitat, shifts fish and can carry pollutants that lead to “unfishable” and “unswimmable” conditions, according to the Minnesota Pollution Control Agency.
Bank stabilization projects such as that done in the DeRuyters’ backyard are called revetments, a biological engineering method that plants willow bushes among locally harvested cedar trees that are secured to the riverbank with deeply sunk aluminum anchors. The trees are overlapped like shingles and interlinked end-to-end with cables; over time, Perry said, the bushes with large root systems secure the banks and prevent erosion.
Money from the Clean Water Fund would address severe erosion with structural stabilization using large boulders at “high-risk, high-volume sites where the erosion is absolutely at its worse,” Perry said.
Perry said Anoka County is in touch with upstream partners to let them know what they’re doing and encourage them to follow suit. He said plans are coming together as part of a larger initiative with the DNR and soil and water conservation districts to protect the Rum upstream.