Washington County Lake Quality
Wisconsin, 15 lakes, average grade A (Excellent)
There are 15 graded lakes in Washington County. The mix is varied enough that the county-level average tells you the broad strokes, not the choose-this-cabin specifics. On average, Washington County lakes grade an A. That puts it near the top of the Wisconsin county ranking.
A meaningful share of Washington's lakes break 50 feet of depth, which matters because deep lakes hold cooler water all summer and resist the resuspended-sediment problems that plague shallow basins. The county's best-graded lake is Green Lake (A).
Quick Answers for Washington County
Planning a trip? Check special fishing regulations for Green Lake, whether the fish are safe to eat, and the best times to fish — or browse the full Wisconsin regulations index.
All Lakes in Washington County
| Rank | Lake | Grade | Clarity | Max Depth | Phosphorus |
|---|---|---|---|---|---|
| 1 | Green Lake | A | 31.2 ft | 37 ft | 16.6 µg/L |
| 2 | Pike Lake | A | 22.1 ft | 45 ft | 19.3 µg/L |
| 3 | Lake Five | A | 39.4 ft | 23 ft | 14.7 µg/L |
| 4 | Big Cedar Lake | A | 16.4 ft | 105 ft | 14.1 µg/L |
| 5 | Little Cedar Lake | A | 33.8 ft | - | 12.1 µg/L |
| 6 | Amy Bell Lake | A | - | 37 ft | 19.5 µg/L |
| 7 | Big Cedar Lake-North Site-Near West Bend | A | 12 ft | 105 ft | 17.5 µg/L |
| 8 | Big Cedar Lake-South Site-Near West Bend | A | 12.5 ft | 105 ft | 15 µg/L |
| 9 | Little Friess Lake | A | 26.2 ft | 34 ft | 26.1 µg/L |
| 10 | Druid Lake | A | 18 ft | 53 ft | 23.7 µg/L |
| 11 | Big Cedar Lake | A | 14.4 ft | 105 ft | 15.5 µg/L |
| 12 | Bark Lake | B | 18 ft | 34 ft | 33 µg/L |
| 13 | Friess Lake | B | 15.6 ft | 48 ft | 33 µg/L |
| 14 | Smith Lake | B | 13.1 ft | - | - |
| 15 | Big Cedar Lake Northern Basin Deep Site | B | 8.7 ft | 105 ft | 21 µg/L |
Source: EPA National Aquatic Resource Surveys, 2026.