Long Lake

Long Lake earns an A — water clarity, phosphorus, and chlorophyll-a all rate among the best monitored waters in Polk County. 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.

Mesotrophic conditions dominate at Long Lake: enough nutrients for a healthy fishery, not so much that algal blooms become a chronic problem. The lake bottoms out at 44 ft — a moderate depth that supports a warm-water fishery without the year-round cold refuge a deeper basin provides. At 61 acres, Long Lake sits below the Wisconsin median: a small water where shoreline activity has an outsized effect on water quality. Among the 77 graded lakes in Polk County, Long Lake sits at rank 29, above the county median.

An invasive species record — Chinese Mystery Snail — has been logged at Long 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 Long 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.