Lake Ann
Benzie County, WisconsinLimited DataOligotrophic
Lake Ann is a cold, clear oligotrophic lake in Benzie County, MI. Water quality is graded B based on 1 sampling years through 2023. The lake supports 10 documented fish species including Bluntnose minnow, Common shiner, and Creek chub. Compared to the 34 other monitored lakes in Benzie County, Lake Ann ranks #19 for water quality.
Source: EPA Water Quality Portal sampling records, local state DNR records, last sampled 2023-06-24. 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 13.8 ft. Trophic State Index: 39.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 13.8 ft | B |
| Phosphorus | No data | |
| Chlorophyll-a (Algae) | No data | |
| Trophic State Index (TSI) | 39 | Oligotrophic |
Low nutrients, clear water, excellent for swimming
Fish Species
Click a species to see all Wisconsin and Minnesota lakes where it is found.
→ Best fishing times for Lake Ann (14-day solunar calendar)
→ Is it safe to eat fish from Lake Ann? (mercury & PFAS guide)
→ Lake Ann fishing regulations (limits, seasons, special rules)
Location
County Ranking
Ranked #19 of 35 lakes in Benzie County
Cleaner Lakes Within 30 Miles
Lake Ann holds Grade B. 4 nearby lakes hold higher grades.
- ARansom LakeBenzie County · 1.2 mi · Higher grade (B → A)
- ALake View; Almira TwpBenzie County · 1.3 mi · Higher grade (B → A)
- ALake Ann Southeast Basin; Almira Township Section 26Benzie County · 0.4 mi · Higher grade (B → A)
- AUpper Woodcock Lake; Almira TwpBenzie County · 1.8 mi · Higher grade (B → A)
Nearby Lakes in Benzie 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
Oligotrophic Lakes in Wisconsin
EPA Impairment Status
Lake Ann 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 MI040601040202-01 · 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: 2023-06-24
Monitoring stations: 1