Image of the new earthen dam upstream from Lake Redwood courtesy Redwood SWCD

A new earthen dam and series of terraces was built three miles upstream from Lake Redwood late last year, and farmers and other landowners should see improvements in flood and erosion control starting this spring. The dam and terraces are designed to control water volume and velocity to protect infrastructure and improve water quality.

Together, the projects in Redwood Falls Township will keep an estimated 2,060 tons of sediment out of Lake Redwood every year — achieving 11% of the reduction goal for the subwatershed.

According to Area II Minnesota River Basin Projects Executive Director Kerry Netzke, the $180,000 investment was paid for largely by the Minnesota Board of Water and Soil Resources, and the USDA. The City of Redwood Falls contributed $32,850 to the projects, covering 15 percent of both projects, and reducing landowners’ costs to 10 percent.

The Redwood River begins atop the Buffalo Ridge in northeastern Pipestone County. The elevation change makes it prone to flash-flooding, because the water picks up speed — and sediment — as it flows 127 miles north and east to the Minnesota River just north of Redwood Falls. Over the past 100 years, increased agricultural drainage has increased the volume of water that enters the river. Additionally, heavy rains have become increasingly frequent.

Both projects will help to extend the life of the $8.5 million Lake Redwood hydraulic dredging project that removed 682,880 cubic yards of sediment, increasing the lake’s depth from 2.5 feet to 20 feet.

Tim Woelfel, a landowner near the river, stated, “I think for the residents of Redwood Falls and the surrounding community, the ability to now recreationally use the lake moreso than what it had been in the past is a benefit. Just the fact that you see boats … I didn’t know if people would utilize it that much, but it has been used.”