Little Portage Lake

Little Portage Lake sits at a C on the grading scale — not impaired, not pristine, with summer measurements that vary year to year. Clarity is the limiting factor — phosphorus is reasonable but suspended particles or algal cells keep water transparency below Wisconsin norms.

A TSI near 49 places Little Portage Lake in the mesotrophic band — moderate productivity, with seasonal swings between clearer spring water and richer late-summer conditions. At only 11 ft deep, Little Portage Lake is shallow — wind keeps the water column mixed and sediment resuspension drives phosphorus levels harder to manage. At 160 acres, Little Portage Lake fits the Wisconsin median for monitored lakes, with partial shoreline records. Within the 191 graded lakes of Vilas County, Little Portage Lake sits at rank 156, near the bottom of the county list.

Little Portage Lake has no invasive species recorded in Wisconsin state databases as of 2026, though prevention practices still apply at all access points. The fishery is bass-led, with 4 documented species across the lake's records. 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.