Winona Lake

Winona Lake earns an F: 93 µg/L of phosphorus and clarity at 2.0 ft signal heavy nutrient loading from the surrounding watershed. Clarity, phosphorus, and chlorophyll-a all rate similarly, so there is no obvious single lever to pull on watershed management.

At a TSI of 68, Winona Lake reads as eutrophic — nutrient-rich enough that summer algal growth and reduced clarity are expected, not unusual. At only 9 ft deep, Winona Lake is shallow — wind keeps the water column mixed and sediment resuspension drives phosphorus levels harder to manage. At 213 acres, Winona Lake fits the Minnesota median for monitored lakes, with 5.4 miles of shoreline. Winona Lake ranks 51 of 51 in Douglas County — at the lower end of the locally monitored distribution.

Winona Lake has no invasive species recorded in Minnesota state databases as of 2024, though prevention practices still apply at all access points. Walleye are documented at Winona Lake, one of 11 fish species on record for the lake. A documented public access point at Winona Lake makes the lake usable for shore fishing, paddle craft, and trailered boats. The lake has a partial ice record — 13 observed ice-outs, centered near Apr 10. Monitoring depth is thin here: the LakeGrade rubric is applied to a small number of sample years, and the grade will be revised as more data accumulates.