Mitchell Lake
Black Hawk County, WisconsinEutrophic
Mitchell Lake is a productive, nutrient-rich eutrophic lake in Black Hawk County, IA. Water quality is graded D based on 2 sampling years through 2024. Compared to the 6 other monitored lakes in Black Hawk County, Mitchell Lake ranks #1 for water quality.
Source: EPA Water Quality Portal sampling records, local state DNR records, last sampled 2024-10-23. Grade methodology: LakeGrade methodology.
Swimming Safety
Swimming not recommended, poor water quality with high algae risk
Water Quality Grade: D, Poor
Very murky, less than 2.3 ft of visibility. Chlorophyll-a: 18.7 µg/L. Trophic State Index: 62.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 2.3 ft | F |
| Phosphorus | No data | |
| Chlorophyll-a (Algae) | 18.7 µg/L | C |
| Trophic State Index (TSI) | 62 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Location
County Ranking
Ranked #1 of 7 lakes in Black Hawk County
Nearby Lakes in Black Hawk County
More Wisconsin Lake Rankings
Other Grade D Lakes in Wisconsin
Eutrophic Lakes in Wisconsin
EPA Impairment Status
Mitchell Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5).
Causes of impairment
Source: EPA ATTAINS assessment unit IA 02-CED-463 · Official waterbody report · Matched by proximity (2.57 km)
Data Sources
Water quality data from the EPA Water Quality Portal
Impairment status from EPA ATTAINS 303(d) database
Grading methodology based on Metropolitan Council standards
Most recent sample: 2024-10-23
Monitoring stations: 1