Shoreline Work, Dredging, Algae Prevention Part of State's 2026 Lake Restoration Plan

We hike Pulpit Rock for the views — and for the stories waiting at the top. Support Decorah News today. The Iowa Department of Natural Resources has about $9.6 million annually of state appropriated money to improve water quality and recreational opportunities at Iowa lakes. Most of these projects take several years to complete, but DNR's annual report for 2025 and plan for 2026 show shoreline work, sediment removal, nutrient reduction and chemical treatments that inactivate lake phosphorus continue to be priorities. Since 2006 when the Lake Restoration program was initiated, the department has removed nearly 8 million cubic yards of excess sediment, enhanced 14,000 acres of wetland and shallow lakes, completed more than 60 infrastructure improvement projects and worked with partners to install more than 700 watershed best management practices. According to DNR, the projects completed with the program have an average cost share of 37% with other partners. To date, the Lake Restoration Program has invested more than $176 million into 72 Iowa lakes. In fiscal year 2025, which ran from July 1, 2024 through June 30, 2025, the report details major restoration projects at lakes across the state, some of which are still in the works for 2026. Projects like shoreline restoration, sediment removal, the construction of sediment and nutrient ponds upstream and fish habitat restoration were listed as major restorations at Three Mile Lake, Casey Lake, Lake Keomah and Little Storm Lake, according to the DNR report. The report notes that shoreline restoration and dam improvements for Lake Keomah will continue into 2026, as will similar projects at McKinley Lake. Lake restoration projects that have been completed or are underway in Iowa. (Map courtesy of Iowa DNR) DNR also conducted flood restoration and flood prevention strategies at Cedar Lake and the Iowa Great Lakes in 2025. The Iowa Great Lakes had more than 90 miles of collapsed shoreline, according to DNR, due to flooding in 2024 that caused "extensive" erosion in West Okoboji Lake, East Okoboji Lake, Big Spirit Lake and Silver Lake. The Lake Restoration Project helped to restore shoreline slope at 33 sites around the Iowa Great Lakes and the public shoreline at Triboji in 2025. Additional bank stabilization projects for the lakes are slated for 2026, according to the plan. Green Valley Lake and Prairie Rose Lake were treated with alum in 2025 to help neutralize the excess phosphorus in the water. Excess phosphorus, according to the report, is the "primary contributor" to algae blooms in Iowa lakes. According to DNR, the excess phosphorus comes from up the watershed, but also can be "internally recycled" as sediment in the lake is stirred up. DNR started treating lakes with alum, or aluminum sulfate, which binds to soluble phosphorus in the lake and brings it to the surface of the water, thus reducing the phosphorus release into the water. According to the report, the alum treatments at Green Valley and Prairie Rose lakes led to clearer water — as much as 15 feet of visibility — and fewer algae blooms throughout the summer season. Lake of Three Fires and Silver Lake are slated for alum treatments in the coming year. DNR also noted it will prioritize beach restoration work in 2026, to reduce bacteria concentrations at Brushy Creek Lake, Big Creek Lake and Hickory Grove Lake. In the 2025 lake recreational season DNR reported beach closures as 28 state park beaches, at least once, because of high levels of E. coli or microcystins, a toxin released by certain types of algae. DNR's draft plan said runoff from rain events "contributes to ongoing issues" with indicator bacteria at Brushy Creek Lake and Big Creek Lake beaches. The department plans to improve these issues with best management practices, like grassed waterways, sediment control basins, streamside buffers, terraces and other practices to catch nutrients and sediment up the watershed. DNR plans to address Hickory Grove Lake's beaches with stormwater management improvements with help from a $25 million, 20-year, Water and Land Legacy bond approved by Story County voters. According to DNR, Iowa's lakes are an "important" part of its economy. More than 60% of Iowans say they visit a lake at least once a year and $1.32 billion in annual spending can be attributed to lake recreation. DNR said at the current allocation rate for the Lake Restoration Program, the department will be able to "stay on schedule with implementing restoration efforts" at the designated lakes and wetlands outlined in the report. "Current and future appropriations will be critical to complete current projects and initiate new projects during FY27-FY31," the plan said. The Legislature approved $9.6 million for the program for fiscal year 2026. More information about the Lake Restoration Program, project cost and detailed plans for each lake can be found in the report. DNR is accepting public comments on the report through Dec. 17. Comments may be sent to via email to michelle.balmer@dnr.iowa.gov or sent via mail to Michelle Balmer Iowa Department of Natural Resources, 6200 Park Avenue, Suite 200, Des Moines, Iowa 50321. Don't miss a beat! Subscribe for free and receive the stories, insights, and events that keep your community thriving.