Oneka Lake

On the scoring rubric Oneka Lake grades a D: clarity at 4.4 ft and phosphorus readings still being added keep it in the lower bracket for Washington County.

At a TSI of 56, Oneka Lake reads as eutrophic — nutrient-rich enough that summer algal growth and reduced clarity are expected, not unusual. The lake's maximum depth is not yet documented in state morphometric records — context for its physical structure remains limited. The lake's surface area is not consistently recorded across state datasets — physical context remains partial. Oneka Lake ranks 30 of 31 in Washington County — at the lower end of the locally monitored distribution.

No invasive species are currently listed at Oneka Lake — the lake remains off the Minnesota infested-waters roster. The state fisheries records do not list documented species for Oneka Lake, which usually reflects a lack of formal fisheries survey work rather than an empty lake. A documented public access point at Oneka Lake makes the lake usable for shore fishing, paddle craft, and trailered boats. 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.