Big Traverse Bay Lake

Big Traverse Bay Lake sits at a C on the grading scale — not impaired, not pristine, with summer measurements that vary year to year. The two scored sub-grades — clarity and phosphorus — track close together, so neither one is dragging the average down.

Eutrophic conditions are the baseline here: clarity drops noticeably in late summer, and dissolved oxygen near the bottom can become a concern. 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. Big Traverse Bay Lake sits at rank 8 of 11 in Lake of the Woods County, in the lower half of the local distribution.

Zebra mussels have been documented at Big Traverse Bay Lake, which alters the filter-feeding balance and can paradoxically increase water clarity while disrupting the food web. The state fisheries records do not list documented species for Big Traverse Bay Lake, which usually reflects a lack of formal fisheries survey work rather than an empty lake. 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.