Square Lake

Square Lake earns an A — water clarity, phosphorus, and chlorophyll-a all rate among the best monitored waters in Washington County. Clarity, phosphorus, and chlorophyll-a all rate similarly, so there is no obvious single lever to pull on watershed management.

Trophically, Square Lake reads as oligotrophic — nutrient-poor, clear, and ecologically more sensitive to disturbance than richer lakes. Square Lake is unusually deep for Minnesota at 68 ft, which buffers the lake against summer warming and helps the deep water stay oxygenated. At 203 acres, Square Lake fits the Minnesota median for monitored lakes, with 2.4 miles of shoreline. Square Lake ranks 1 of 31 in Washington County, putting it in the upper tier of locally monitored lakes.

No invasive species are currently listed at Square Lake — the lake remains off the Minnesota infested-waters roster. Bass fishing is part of the appeal: the species list runs to 9, anchored by largemouth and/or smallmouth bass. Public access is available — the lake is on the Minnesota PCA public-access list. 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.