D
Lake Koshkonong - N of Charley Bluff Landing
Jefferson County, Wisconsin
Water Quality Grade: D — Poor
Murky — only visible to about 6.1 feet. Phosphorus level: 282 µg/L.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 1.85 m | D |
| Phosphorus | 282 µg/L | F |
| Chlorophyll-a (Algae) | No data |
County Ranking
Ranked #10 of 10 lakes in Jefferson County
Data Sources
Data from the EPA Water Quality Portal
Grading methodology based on Metropolitan Council standards
Most recent sample: 2025-09-09
Monitoring stations: 1