Boy Lake

On the LakeGrade scale Boy Lake grades a B, with clarity at 8.9 ft and 21 µg/L of phosphorus placing it above the Minnesota median. 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 sits in the mesotrophic zone — the band where most well-managed Minnesota lakes fall. The lake bottoms out at 45 ft — a moderate depth that supports a warm-water fishery without the year-round cold refuge a deeper basin provides. With 3,308 acres of surface and 21.6 miles of shoreline, Boy Lake is a large water by Minnesota standards — recreational pressure is spread across a long shoreline. Within the 133 graded lakes of Cass County, Boy Lake sits at rank 115, near the bottom of the county list.

Boy Lake is on the Minnesota infested-waters list for zebra mussels — boaters should follow clean-drain-dry protocols when moving gear to or from the lake. Muskie are on the species list at Boy Lake, alongside the lake's 20 other documented fish. Public access is available — the lake is on the Minnesota PCA public-access list. 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.