Vernon County Lake Quality
Wisconsin, 1 lakes, average grade B (Good)
Vernon County has 1 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. With an average grade of B, Vernon County sits comfortably above the Wisconsin median.
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. Sidie Hollow Lake (B) is the cleanest in the county.
Quick Answers for Vernon County
Planning a trip? Check special fishing regulations for Sidie Hollow Lake, whether the fish are safe to eat, and the best times to fish — or browse the full Wisconsin regulations index.
DNR Reports (2)
Wisconsin DNR Fisheries Survey resources for lakes in Vernon County. browse all reports →
- 2025Lower Reno Bottoms Mississippi River fall survey, 2025Fisheries Survey · WI DNR · 2025 (PDF)
- 2024Sidie Hollow Lake fishery survey, 2024Fisheries Survey · WI DNR · 2024 (PDF)
All Lakes in Vernon County
| Rank | Lake | Grade | Clarity | Max Depth | Phosphorus |
|---|---|---|---|---|---|
| 1 | Sidie Hollow Lake | B | 12 ft | 22 ft | - |
Source: EPA National Aquatic Resource Surveys, 2026.