Lost Lake

Lost Lake sits at the top of the Wisconsin DNR grading rubric with an A, a mark reached by the cleanest lakes in Wisconsin. Clarity, phosphorus, and chlorophyll-a all rate similarly, so there is no obvious single lever to pull on watershed management.

A TSI value of 38 puts Lost Lake in the oligotrophic range, where biological productivity stays low and the water column remains clear. The lake's maximum depth is not yet documented in state morphometric records — context for its physical structure remains limited. Lost Lake is small — 51 acres alongside partial shoreline records — which makes it sensitive to even modest changes in watershed runoff or recreational pressure. Within Sawyer County's 52 graded waters, Lost Lake sits at rank 11, near the top of the local distribution.

Lost Lake has no invasive species recorded in Wisconsin state databases as of 2024, though prevention practices still apply at all access points. Bass fishing is part of the appeal: the species list runs to 2, anchored by largemouth and/or smallmouth bass. Multiple sampling years from the Wisconsin DNR Citizen Lake Monitoring Network back the grade, so the letter should hold steady absent a major watershed shift.