Boulder Lake

Boulder Lake carries a solid B grade — strong on most parameters, with measurements that hold up well across the summer season. 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's maximum depth is not yet documented in state morphometric records — context for its physical structure remains limited. The lake's surface area is not consistently recorded across state datasets — physical context remains partial. Among the 142 graded lakes in Lake County, Boulder Lake sits at rank 54, above the county median.

No invasive species are currently listed at Boulder Lake — the lake remains off the Minnesota infested-waters roster. The state fisheries records do not list documented species for Boulder Lake, which usually reflects a lack of formal fisheries survey work rather than an empty lake. No formal public access is documented at Boulder Lake — most use is by shoreline residents and their guests. 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.