East Twin Lake

East Twin Lake earns an A — water clarity, phosphorus, and chlorophyll-a all rate among the best monitored waters in Oneida County. Sub-grades cluster within a single letter of each other, which usually means the lake is in stable trophic balance rather than fighting one specific stressor.

The lake's low TSI puts it in oligotrophic territory — the cleanest of the four trophic classes, but also the most vulnerable to nutrient-driven shifts. A maximum depth of 17 ft puts East Twin Lake in the middle of Wisconsin's depth distribution. East Twin Lake is small — 44 acres alongside partial shoreline records — which makes it sensitive to even modest changes in watershed runoff or recreational pressure. Among the 140 graded lakes in Oneida County, East Twin Lake sits at rank 56, above the county median.

No invasive species are currently listed at East Twin Lake — the lake remains off the Wisconsin infested-waters roster. Bass fishing is part of the appeal: the species list runs to 3, anchored by largemouth and/or smallmouth bass. 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.