Sanilac County Lake Quality
Wisconsin, 2 lakes, average grade A (Excellent)
Sanilac 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.
The county's lakes lean shallow, which makes the grades sensitive to wind, sediment-resuspension, and any nutrient inputs from the watershed. The cleanest lake on the books is Hu09 Lake (A); the most-stressed is Hu09 Lake (A).
Quick Answers for Sanilac County
Planning a trip? Check special fishing regulations for Hu09 Lake, whether the fish are safe to eat, and the best times to fish — or browse the full Wisconsin regulations index.
All Lakes in Sanilac County
| Rank | Lake | Grade | Clarity | Max Depth | Phosphorus |
|---|---|---|---|---|---|
| 1 | Hu09 Lake | A | 42.7 ft | - | - |
| 2 | Csmi 2017 Station Mz22 Lake | A | 39.4 ft | - | - |
Source: EPA National Aquatic Resource Surveys, 2026.