Montezuma - Poweshiek County Conservation and the Iowa Department of Natural Resources (DNR) will discuss upcoming lake restoration efforts planned for Diamond Lake at an open house on Nov. 12, at 6 p.m., at the Foster Center at Diamond Lake County Park. Work is scheduled from summer 2026 through early spring 2028.
The meeting will present project goals, construction plans, and what park users can expect over the next three years. Restoration work will include draining the lake to facilitate targeted dredging, shoreline stabilization, restoring the campground marsh, dam infrastructure upgrades, fishery renovation, and shoreline access improvements.
Several watershed ponds were renovated and installed in the park in 2025 to help protect Diamond Lake by capturing sediment and nutrient runoff from the watershed before it enters the lake. Park staff have also worked extensively to restore timber stands throughout the park by removing invasive species from the forest understory. The City of Montezuma, which uses Diamond Lake as a drinking water source, constructed a well last summer that will allow the lake to be drained for this restoration project.
Diamond Lake, a 98-acre lake located in the 660-acre park, has a history of poor water quality, including poor water clarity, a lack of fish habitat, and frequent algae blooms. Project partners have worked over the past several years to assess these issues and develop a comprehensive lake restoration plan to improve water quality and recreational opportunities.
Diamond Lake is a popular recreation destination, drawing more than 45,000 visitors annually. The campground at the park is consistently busy, and the park hosts several popular events for the community throughout the year, as well as being a local hunting destination. Funding for restoration efforts include the Lake Restoration Program, a state funded program administered by the Iowa DNR, Diamond County Conservation, and the City of Montezuma.