Montgomery County Lake Quality
Wisconsin, 2 lakes, average grade F (Very Poor)
Only 2 lakes in Montgomery 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 average is F — the most-stressed bracket in our rubric. Most monitored lakes here show persistent nutrient loading and algal pressure.
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. Glenn Shoals Lake (F) is the cleanest in the county.
Quick Answers for Montgomery County
Planning a trip? Check special fishing regulations for Glenn Shoals Lake, whether the fish are safe to eat, and the best times to fish — or browse the full Wisconsin regulations index.
All Lakes in Montgomery County
| Rank | Lake | Grade | Clarity | Max Depth | Phosphorus |
|---|---|---|---|---|---|
| 1 | Glenn Shoals Lake | F | 1 ft | - | 91 µg/L |
| 2 | Lou Yaeger Lake | F | 1.8 ft | - | 217 µg/L |
Source: EPA National Aquatic Resource Surveys, 2026.