Loon Lake

Loon Lake carries a solid B grade — strong on most parameters, with measurements that hold up well across the summer season. The three sub-grades — clarity, phosphorus, and chlorophyll-a — track close together, so no single parameter is dragging the average.

A TSI value of 39 puts Loon Lake in the oligotrophic range, where biological productivity stays low and the water column remains clear. At 69 ft of maximum depth, Loon Lake stratifies reliably through the summer — the hypolimnion stays cooler and clearer than the surface layer suggests. At 231 acres, Loon Lake fits the Minnesota median for monitored lakes, with 3.6 miles of shoreline. Loon Lake sits at rank 77 of 141 in Itasca County, in the lower half of the local distribution.

No invasive species are currently listed at Loon Lake — the lake remains off the Minnesota infested-waters roster. The fishery includes walleye alongside the lake's other 12 documented species — a notable draw for Minnesota anglers. A documented public access point at Loon Lake makes the lake usable for shore fishing, paddle craft, and trailered boats. Ice-out has been recorded 16 times at Loon Lake, with a median around Apr 18. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.