Clinton County Lake Quality
Wisconsin, 3 lakes, average grade A (Excellent)
Only 3 lakes in Clinton County carry an active grade. The county-level summary is therefore representative of those specific lakes, not necessarily of every water body in the county. The county's average grade is A — among the cleanest in New York. 3 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 Isle la Motte Lake (A); the most-stressed is Isle la Motte Lake (A).
Quick Answers for Clinton County
Planning a trip? Check special fishing regulations for Isle la Motte Lake, whether the fish are safe to eat, and the best times to fish — or browse the full Wisconsin regulations index.
All Lakes in Clinton County
| Rank | Lake | Grade | Clarity | Max Depth | Phosphorus |
|---|---|---|---|---|---|
| 1 | Isle la Motte Lake | A | 15.4 ft | - | 8.7 µg/L |
| 2 | Isle la Motte Lake | A | 12.5 ft | - | 12.3 µg/L |
| 3 | Main Section Lake | A | 14.8 ft | - | 9.4 µg/L |
Source: EPA National Aquatic Resource Surveys, 2026.