Ludington Lake-Deep Hole

Ludington Lake-Deep Hole sits at a C on the grading scale — not impaired, not pristine, with summer measurements that vary year to year. Clarity, phosphorus, and chlorophyll-a all rate similarly, so there is no obvious single lever to pull on watershed management.

A TSI near 44 places Ludington Lake-Deep Hole in the mesotrophic band — moderate productivity, with seasonal swings between clearer spring water and richer late-summer conditions. The lake bottoms out at 30 ft — a moderate depth that supports a warm-water fishery without the year-round cold refuge a deeper basin provides. Ludington Lake-Deep Hole is small — 29 acres alongside partial shoreline records — which makes it sensitive to even modest changes in watershed runoff or recreational pressure. Within the 34 graded lakes of Forest County, Ludington Lake-Deep Hole sits at rank 30, near the bottom of the county list.

No invasive species are currently listed at Ludington Lake-Deep Hole — the lake remains off the Wisconsin infested-waters roster. Bass fishing is part of the appeal: the species list runs to 2, anchored by largemouth and/or smallmouth bass. Public access is available — the lake is on the Wisconsin DNR public-access list. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.