Irogami Lake

Irogami Lake pulls a D on the LakeGrade rubric — phosphorus loading and limited clarity hold it below the Wisconsin average. 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.

At a TSI of 57, Irogami Lake reads as eutrophic — nutrient-rich enough that summer algal growth and reduced clarity are expected, not unusual. A maximum depth of just 5 ft means sediment-bound phosphorus releases back into the water column whenever wind stirs the bottom — a classic shallow-lake dynamic. At 290 acres, Irogami Lake fits the Wisconsin median for monitored lakes, with partial shoreline records. Within the 32 graded lakes of Waushara County, Irogami Lake sits at rank 32, near the bottom of the county list.

Zebra mussels have been documented at Irogami Lake, which alters the filter-feeding balance and can paradoxically increase water clarity while disrupting the food web. The fishery is bass-led, with 3 documented species across the lake's records. Public access is available — the lake is on the Wisconsin DNR 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.