Grindle Lake

On the LakeGrade scale Grindle Lake grades a B, with clarity at 9.0 ft and 12 µg/L of phosphorus placing it above the Wisconsin median. The lake's weakest score is on Secchi depth — the water looks more turbid than its phosphorus number alone would predict.

The lake sits in the mesotrophic zone — the band where most well-managed Wisconsin lakes fall. Grindle Lake reaches 23 ft at its deepest point — typical for Wisconsin mid-sized lakes, with seasonal stratification but limited cold-water refuge. At 40 acres, Grindle Lake sits below the Wisconsin median: a small water where shoreline activity has an outsized effect on water quality. Within Oconto County's 62 graded lakes, Grindle Lake ranks 37 — below the local median, though not at the bottom.

An invasive species record — Chinese Mystery Snail — has been logged at Grindle Lake; Wisconsin DNR maintains the official infested-waters list. The fishery is bass-led, with 3 documented species across the lake's records. A documented public access point at Grindle Lake makes the lake usable for shore fishing, paddle craft, and trailered boats. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.