Mackinac County Lake Quality
Wisconsin, 2 lakes, average grade A (Excellent)
Mackinac County has 2 graded lakes — a thin enough sample that one or two stressed lakes can move the county average noticeably. Use the per-lake pages below for what actually matters. The county's average grade is A — among the cleanest in Michigan. 2 lakes pull an A on their own, and almost none fall into the D or F brackets.
Most of the county's monitored lakes are shallow — under 50 feet — which means wind keeps the water column mixed all summer and sediment-bound phosphorus releases back into the surface layer whenever the bottom is disturbed. Csmi 2017 Station Hu329 Lake (A) is the cleanest in the county.
Quick Answers for Mackinac County
Planning a trip? Check special fishing regulations for Csmi 2017 Station Hu329 Lake, whether the fish are safe to eat, and the best times to fish — or browse the full Wisconsin regulations index.
All Lakes in Mackinac County
| Rank | Lake | Grade | Clarity | Max Depth | Phosphorus |
|---|---|---|---|---|---|
| 1 | Csmi 2017 Station Hu329 Lake | A | 39.4 ft | - | - |
| 2 | Csmi 2015 Station 76442 Lake | A | - | - | - |
Source: EPA National Aquatic Resource Surveys, 2026.