Long Lake

Long Lake earns an A — water clarity, phosphorus, and chlorophyll-a all rate among the best monitored waters in Cass County. 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 lake's low TSI puts it in oligotrophic territory — the cleanest of the four trophic classes, but also the most vulnerable to nutrient-driven shifts. A maximum depth of 37 ft puts Long Lake in the middle of Minnesota's depth distribution. At 246 acres, Long Lake fits the Minnesota median for monitored lakes, with 5.1 miles of shoreline. Within Cass County's 133 graded waters, Long Lake sits at rank 4, near the top of the local distribution.

No invasive species are currently listed at Long Lake — the lake remains off the Minnesota infested-waters roster. Walleye are documented at Long Lake, one of 12 fish species on record for the lake. A documented public access point at Long 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.