Base Line Lake
Washtenaw County, WisconsinLimited DataMesotrophic
Base Line Lake is a mesotrophic lake in Washtenaw County, MI. Water quality is graded B based on 1 sampling years through 2024. The lake supports 1 documented fish species including Brindled madtom. Compared to the 16 other monitored lakes in Washtenaw County, Base Line Lake ranks #6 for water quality.
Source: EPA Water Quality Portal sampling records, local state DNR records, last sampled 2024-07-11. 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 11 ft. Trophic State Index: 43.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 11 ft | B |
| Phosphorus | No data | |
| Chlorophyll-a (Algae) | No data | |
| Trophic State Index (TSI) | 43 | 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 Base Line Lake (14-day solunar calendar)
→ Is it safe to eat fish from Base Line Lake? (mercury & PFAS guide)
→ Base Line Lake fishing regulations (limits, seasons, special rules)
Location
County Ranking
Ranked #6 of 17 lakes in Washtenaw County
Nearby Lakes in Washtenaw 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
Base Line 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 MI040900050307-11 · 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: 2024-07-11
Monitoring stations: 1