Swan Lake

Swan Lake earns an A — water clarity, phosphorus, and chlorophyll-a all rate among the best monitored waters in Otter Tail County. Clarity, phosphorus, and chlorophyll-a all rate similarly, so there is no obvious single lever to pull on watershed management.

The lake sits in the mesotrophic zone — the band where most well-managed Minnesota lakes fall. The lake bottoms out at 44 ft — a moderate depth that supports a warm-water fishery without the year-round cold refuge a deeper basin provides. The lake's 749 acres and 9.2 miles of shoreline put it in the mid-range bucket — large enough for varied use, small enough that watershed inputs reach the whole basin. Swan Lake ranks 34 of 97 in Otter Tail County — solidly in the upper half of the local distribution.

Zebra mussel presence at Swan Lake means the lake's clarity numbers carry an asterisk — filtered water is not the same as nutrient-poor water. Walleye are documented at Swan Lake, one of 16 fish species on record for the lake. Public access is available — the lake is on the Minnesota PCA public-access list. Ice-out has been recorded 17 times at Swan Lake, with a median around Apr 18. 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.