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. Clarity, phosphorus, and chlorophyll-a all rate similarly, so there is no obvious single lever to pull on watershed management.

The lake sits in the mesotrophic zone — the band where most well-managed Minnesota lakes fall. Long Lake reaches 25 ft at its deepest point — typical for Minnesota mid-sized lakes, with seasonal stratification but limited cold-water refuge. At 53 acres, Long Lake sits below the Minnesota median: a small water where shoreline activity has an outsized effect on water quality. Among the 31 graded lakes in Washington County, Long Lake sits at rank 10, above the county median.

Long Lake carries an invasive watermilfoil record — boat-launch decontamination and shoreline care matter more here than at uninfested lakes. 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. The lake has a partial ice record — 5 observed ice-outs, centered near 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.