Fountain Lake

Fountain Lake grades an F: water clarity, phosphorus, and chlorophyll-a all rate poorly, placing it among the most stressed lakes monitored in Minnesota. Sub-grades cluster within a single letter of each other, which usually means the lake is in stable trophic balance rather than fighting one specific stressor.

The hypereutrophic status — TSI 71 — reflects sustained heavy nutrient loading from the surrounding watershed and frequent algal pressure. Fountain Lake is a shallow lake at 14 ft maximum depth, which means it warms quickly, mixes constantly, and amplifies nutrient inputs. The lake's 522 acres and 14.5 miles of shoreline put it in the mid-range bucket — large enough for varied use, small enough that watershed inputs reach the whole basin. Among the 4 graded lakes in Freeborn County, Fountain Lake sits at rank 2, above the county median.

Fountain 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 Fountain Lake, one of 17 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 logged at Fountain Lake more than two dozen times, putting the median around Apr 6 — a useful baseline for tracking climate trends. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.