Guernsey Lake

Guernsey Lake pulls a D on the LakeGrade rubric — phosphorus loading and limited clarity hold it below the Minnesota average. Clarity, phosphorus, and chlorophyll-a all rate similarly, so there is no obvious single lever to pull on watershed management.

At a TSI of 64, Guernsey Lake reads as eutrophic — nutrient-rich enough that summer algal growth and reduced clarity are expected, not unusual. The lake bottoms out at 19 ft — a moderate depth that supports a warm-water fishery without the year-round cold refuge a deeper basin provides. Guernsey Lake covers 121 acres alongside 2.2 miles of shoreline — a mid-sized water that supports a working fishery without being so large that conditions diverge between basins. Guernsey Lake ranks 17 of 17 in Todd County — at the lower end of the locally monitored distribution.

Guernsey Lake is on the Minnesota infested-waters list for zebra mussels — boaters should follow clean-drain-dry protocols when moving gear to or from the lake. Walleye are documented at Guernsey Lake, one of 16 fish species on record for the lake. A documented public access point at Guernsey Lake makes the lake usable for shore fishing, paddle craft, and trailered boats. 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.