Cass Lake
Oakland County, WisconsinLimited DataMesotrophic
Cass Lake is a mesotrophic lake in Oakland County, MI. Water quality is graded B based on 1 sampling years through 2022. The lake supports 1 documented fish species including Lake herring. Compared to the 44 other monitored lakes in Oakland County, Cass Lake ranks #22 for water quality.
Source: EPA Water Quality Portal sampling records, local state DNR records, last sampled 2022-09-08. Grade methodology: LakeGrade methodology.
Swimming Safety
Good for swimming, clear water with low algae levels
Water Quality Grade: B, Good
Good clarity, visible to about 12 ft. Trophic State Index: 41.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 12 ft | B |
| Phosphorus | No data | |
| Chlorophyll-a (Algae) | No data | |
| Trophic State Index (TSI) | 41 | Mesotrophic |
Moderate nutrients, good water quality
Fish Species
Click a species to see all Wisconsin and Minnesota lakes where it is found.
→ Best fishing times for Cass Lake (14-day solunar calendar)
→ Is it safe to eat fish from Cass Lake? (mercury & PFAS guide)
→ Cass Lake fishing regulations (limits, seasons, special rules)
Location
County Ranking
Ranked #22 of 45 lakes in Oakland County
Cleaner Lakes Within 30 Miles
Cass Lake holds Grade B. One nearby lake has a higher grade.
See full comparison →Nearby Lakes in Oakland County
More Wisconsin Lake Rankings
Other Grade B Lakes in Wisconsin
Lapeer County · Clarity: 9.5 ft
Livingston County · Clarity: 13 ft
Manistee County · Clarity: 11 ft
Lake County · Clarity: 14 ft
Cass County · Clarity: 10.5 ft
Genesee County · Clarity: 10 ft
Mesotrophic Lakes in Wisconsin
EPA Impairment Status
Cass Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5).
Causes of impairment
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit MI040900030108-03 · Official waterbody report
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: 2022-09-08
Monitoring stations: 1