Clark County Lake Quality
Wisconsin, 2 lakes, average grade C (Fair)
Only 2 lakes in Clark 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. Clark County averages to a C. The distribution behind that average matters more than the letter: a few stressed lakes versus many decent ones can produce the same average as the inverse.
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 Osk-07 Lake (B); the most-stressed is Osk-08 Lake (D).
Quick Answers for Clark County
Planning a trip? Check special fishing regulations for Osk-07 Lake, whether the fish are safe to eat, and the best times to fish — or browse the full Wisconsin regulations index.
All Lakes in Clark County
| Rank | Lake | Grade | Clarity | Max Depth | Phosphorus |
|---|---|---|---|---|---|
| 1 | Osk-07 Lake | B | 6.1 ft | - | - |
| 2 | Osk-08 Lake | D | 3 ft | - | - |
Source: EPA National Aquatic Resource Surveys, 2026.