Fish Lake

Fish Lake sits at a C on the grading scale — not impaired, not pristine, with summer measurements that vary year to year. The three sub-grades — clarity, phosphorus, and chlorophyll-a — track close together, so no single parameter is dragging the average.

At a TSI of 55, Fish Lake reads as eutrophic — nutrient-rich enough that summer algal growth and reduced clarity are expected, not unusual. Fish Lake reaches 34 ft at its deepest point — typical for Minnesota mid-sized lakes, with seasonal stratification but limited cold-water refuge. Fish Lake is small — 21 acres alongside 0.8 miles of shoreline — which makes it sensitive to even modest changes in watershed runoff or recreational pressure. Fish Lake sits at rank 45 of 83 in Washington County, in the lower half of the local distribution.

No invasive species are currently listed at Fish Lake — the lake remains off the Minnesota infested-waters roster. The state fisheries records do not list documented species for Fish Lake, which usually reflects a lack of formal fisheries survey work rather than an empty lake. No formal public access is documented at Fish Lake — most use is by shoreline residents and their guests. The grade is supported by multiple sampling years from Minnesota PCA volunteers and partner agencies, giving the letter a reasonably stable foundation.