Long Lake

Long Lake earns a C — middle-of-the-pack water quality, with one or two parameters dragging the average down from a stronger grade.

The lake sits in the mesotrophic zone — the band where most well-managed Minnesota lakes fall. A maximum depth of 25 ft puts Long Lake in the middle of Minnesota's depth distribution. Long Lake is small — 53 acres alongside 2.1 miles of shoreline — which makes it sensitive to even modest changes in watershed runoff or recreational pressure. Among the 31 graded lakes in Washington County, Long Lake sits at rank 10, above the county median.

Eurasian watermilfoil is established at Long Lake, which can dampen recreational access and pressure the native plant community. The state fisheries records do not list documented species for Long Lake, which usually reflects a lack of formal fisheries survey work rather than an empty lake. No formal public access is documented at Long Lake — most use is by shoreline residents and their guests. Ice-out has been recorded 5 times at Long Lake, with a median around Apr 12. 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.