Bone Lake

Bone Lake pulls a D on the LakeGrade rubric — phosphorus loading and limited clarity hold it below the Minnesota average. Clarity, phosphorus, and chlorophyll-a all rate similarly, so there is no obvious single lever to pull on watershed management.

A TSI in the eutrophic range signals a lake doing what nutrient-loaded waters do — supporting an active algal community at the cost of clear water. Bone Lake reaches 30 ft at its deepest point — typical for Minnesota mid-sized lakes, with seasonal stratification but limited cold-water refuge. Bone Lake covers 221 acres alongside 3.0 miles of shoreline — a mid-sized water that supports a working fishery without being so large that conditions diverge between basins. Within the 31 graded lakes of Washington County, Bone Lake sits at rank 29, near the bottom of the county list.

Zebra mussel presence at Bone Lake means the lake's clarity numbers carry an asterisk — filtered water is not the same as nutrient-poor water. Walleye are documented at Bone Lake, one of 14 fish species on record for the lake. A documented public access point at Bone Lake makes the lake usable for shore fishing, paddle craft, and trailered boats. Ice-out has been logged at Bone Lake more than two dozen times, putting the median around Apr 13 — a useful baseline for tracking climate trends. 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.