String Lake

On the LakeGrade rubric String Lake fails the cutoffs — a TSI of 93 and persistent algal pressure put it in the bottom tier. 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.

A TSI above 70 puts String Lake in hypereutrophic territory: visible blooms are common, and clarity rarely climbs even in early summer. String Lake is a shallow lake at 4 ft maximum depth, which means it warms quickly, mixes constantly, and amplifies nutrient inputs. At 336 acres, String Lake fits the Minnesota median for monitored lakes, with 7.0 miles of shoreline. Within Cottonwood County's 6 graded lakes, String Lake ranks 4 — below the local median, though not at the bottom.

No invasive species are currently listed at String Lake — the lake remains off the Minnesota infested-waters roster. Walleye are documented at String Lake, one of 11 fish species on record for the lake. A documented public access point at String Lake makes the lake usable for shore fishing, paddle craft, and trailered boats. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.