Mineral Lake

Mineral Lake earns a C — middle-of-the-pack water quality, with one or two parameters dragging the average down from a stronger grade. Clarity is the limiting factor — phosphorus is reasonable but suspended particles or algal cells keep water transparency below Wisconsin norms.

Eutrophic conditions are the baseline here: clarity drops noticeably in late summer, and dissolved oxygen near the bottom can become a concern. The lake bottoms out at 29 ft — a moderate depth that supports a warm-water fishery without the year-round cold refuge a deeper basin provides. At 227 acres, Mineral Lake fits the Wisconsin median for monitored lakes, with partial shoreline records. Within the 10 graded lakes of Ashland County, Mineral Lake sits at rank 8, near the bottom of the county list.

Mineral Lake has no invasive species recorded in Wisconsin state databases as of 2025, though prevention practices still apply at all access points. The fishery includes walleye among the lake's 4 documented species — a notable draw for Wisconsin anglers. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.