Lake County Lake Quality
Wisconsin, 16 lakes, average grade C (Fair)
There are 16 graded lakes in Lake County. The mix is varied enough that the county-level average tells you the broad strokes, not the choose-this-cabin specifics. Lake 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.
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. Loch Lomond Lake (A) is the cleanest in the county.
Quick Answers for Lake County
Planning a trip? Check special fishing regulations for Loch Lomond Lake, whether the fish are safe to eat, and the best times to fish — or browse the full Wisconsin regulations index.
All Lakes in Lake County
| Rank | Lake | Grade | Clarity | Max Depth | Phosphorus |
|---|---|---|---|---|---|
| 1 | Loch Lomond Lake | A | 16.5 ft | - | - |
| 2 | Csmi 2015 Station Eg Lake | A | - | - | - |
| 3 | Timber Lake | B | 10.6 ft | - | - |
| 4 | Round Lake | B | 7.4 ft | - | 19.5 µg/L |
| 5 | Grays Lake | B | 3.5 ft | - | 18 µg/L |
| 6 | Catherine Lake | B | 7.4 ft | - | 27.5 µg/L |
| 7 | Channel Lake | C | 8 ft | - | 34.5 µg/L |
| 8 | Long Lake | D | 3.4 ft | - | 35 µg/L |
| 9 | Hastings Lake | D | 3.4 ft | - | - |
| 10 | Grass Lake | D | 1.4 ft | - | 57.5 µg/L |
| 11 | Long Lake | D | 2.9 ft | - | 41.5 µg/L |
| 12 | Fox Lake | D | 1.9 ft | - | 43 µg/L |
| 13 | Petite Lake | D | 2.5 ft | - | 36 µg/L |
| 14 | Nippersink Lake | D | 1.3 ft | - | 44.5 µg/L |
| 15 | Marie Lake | D | 2.7 ft | - | 69 µg/L |
| 16 | Bluff Lake | D | 4 ft | - | 315.5 µg/L |
Source: EPA National Aquatic Resource Surveys, 2026.