Unnamed Lake

On the scoring rubric Unnamed Lake grades a D: clarity at 1.6 ft and 33 µg/L of phosphorus keep it in the lower bracket for Washington County. The lake's weakest score is on Secchi depth — the water looks more turbid than its phosphorus number alone would predict.

At a TSI of 62, Unnamed Lake reads as eutrophic — nutrient-rich enough that summer algal growth and reduced clarity are expected, not unusual. The lake's 60 ft maximum depth is in the upper tier for Minnesota — deep enough for cold-water fish to find refuge in summer. At 1,799 acres, Unnamed Lake is one of the larger lakes in Washington County, with 16.8 miles of shoreline supporting multiple distinct use patterns. Unnamed Lake ranks 27 of 31 in Washington County — at the lower end of the locally monitored distribution.

Zebra mussels have been documented at Unnamed Lake, which alters the filter-feeding balance and can paradoxically increase water clarity while disrupting the food web. The fishery includes walleye alongside the lake's other 12 documented species — a notable draw for Minnesota anglers. Public access is available — the lake is on the Minnesota PCA public-access list. Ice-out has been recorded 5 times at Unnamed Lake, with a median around Apr 8. 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.