Ellwood Lake

Ellwood Lake sits at the top of the Wisconsin DNR grading rubric with an A, a mark reached by the cleanest lakes in Wisconsin. The three sub-grades — clarity, phosphorus, and chlorophyll-a — track close together, so no single parameter is dragging the average.

A TSI value of 31 puts Ellwood Lake in the oligotrophic range, where biological productivity stays low and the water column remains clear. A maximum depth of 25 ft puts Ellwood Lake in the middle of Wisconsin's depth distribution. At 130 acres, Ellwood Lake fits the Wisconsin median for monitored lakes, with partial shoreline records. Ellwood Lake ranks 12 of 39 in Florence County — solidly in the upper half of the local distribution.

Zebra mussels have been documented at Ellwood Lake, which alters the filter-feeding balance and can paradoxically increase water clarity while disrupting the food web. Bass fishing is part of the appeal: the species list runs to 4, anchored by largemouth and/or smallmouth bass. A documented public access point at Ellwood 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.