Round Lake
Shiawassee County, WisconsinEutrophic
Round Lake is a productive, nutrient-rich eutrophic lake in Shiawassee County, MI. Water quality is graded C based on 2 sampling years through 2023. The lake supports 37 documented fish species including Black bullhead, Black crappie, and Blackchin shiner. Compared to the 5 other monitored lakes in Shiawassee County, Round Lake ranks #4 for water quality.
Source: EPA Water Quality Portal sampling records, local state DNR records, last sampled 2023-09-15. Grade methodology: LakeGrade methodology.
Swimming Safety
Swim with caution, moderate algae may be present
Water Quality Grade: C, Fair
Murky, only visible to about 6 ft. Chlorophyll-a: 19 µg/L. Trophic State Index: 55.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 6 ft | D |
| Phosphorus | No data | |
| Chlorophyll-a (Algae) | 19 µg/L | C |
| Trophic State Index (TSI) | 55 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Fish Species
Click a species to see all Wisconsin and Minnesota lakes where it is found.
→ Best fishing times for Round Lake (14-day solunar calendar)
→ Is it safe to eat fish from Round Lake? (mercury & PFAS guide)
→ Round Lake fishing regulations (limits, seasons, special rules)
Location
County Ranking
Ranked #4 of 6 lakes in Shiawassee County
Cleaner Lakes Within 30 Miles
Round Lake holds Grade C. One nearby lake has a higher grade.
See full comparison →Nearby Lakes in Shiawassee County
More Wisconsin Lake Rankings
Other Grade C Lakes in Wisconsin
Cass County · Clarity: 7 ft
Leelanau County · Clarity: 9.5 ft
Iosco County · Clarity: 5.5 ft
Muskegon County · Clarity: 6.8 ft
Gladwin County · Clarity: 9 ft
Montmorency County · Clarity: 9 ft
Eutrophic Lakes in Wisconsin
EPA Impairment Status
Round 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 MI040802030205-05 · Official waterbody report · Matched by proximity (0.85 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: 2023-09-15
Monitoring stations: 1