Au Sable Lake
Ogemaw County, Michigan269 acresView mapDirections
Clarity, phosphorus, and algae all sit in the cleanest band for this region.
- Mesotrophic
- #2 of 2 in the county
- 52 ft max depth
- Public access
Au Sable Lake in Ogemaw County, Michigan has a water quality grade of A (Excellent). Water clarity: 10.5 ft visibility. Phosphorus: 10 µg/L. Chlorophyll-a (algae): 3.3 µg/L. Maximum depth: 52 ft. Surface area: 268.7 acres.
- Clarity
- 10.5 ft
- Max depth
- 52 ft
- Area
- 269 acres
- Type
- Mesotrophic
- Trend
- → Stable
- Public access
- Yes
Stays via Stay22
Stays near Au Sable Lake
Compare lakeside cabins, hotels, and vacation rentals near Au Sable Lake in Ogemaw County, Michigan — live availability and prices for your trip. Switch the map to Satellite to see the lake and how close each stay is to the water.
Top-rated places to stay near Au Sable Lake
Prices for Sep 11–13, 4 adults. Change dates on the map below.
Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.
Planning a whole trip? See where to stay at Michigan’s top lakes →
Watch Au Sable Lake’s letter
Email me if this lake’s grade moves. Grades stay free.
Or email
Au Sable Lake is a 269-acre mesotrophic lake in Ogemaw County, Michigan with a maximum depth of 52 feet. Water quality is graded A based on 1 sampling years through 2023. Water clarity is improving over recent sampling years. The lake supports 11 documented fish species including Bluegill, Bluntnose minnow, and Iowa darter. Public access is available. Compared to the 1 other monitored lakes in Ogemaw County, Au Sable Lake ranks #2 for water quality.
Source: EPA Water Quality Portal sampling records, EGLE, last sampled 2023-09-09. Grade methodology: LakeQuality methodology.
What Au Sable Lake is good for
From access and monitoring records, not editorial picks.
- Clear water10.5 ft of visibility
- Fishing11 species recorded
- Deep water52 ft surveyed max depth
Swimming Safety
Grade onlyLow algae
Based on clarity and algae grades from past sampling — we do not hold live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
The A is nutrients and algae, not a swimming clearance. Check local advisories before you swim.
Water Quality Grade: A (Excellent)
Good clarity, visible to about 10.5 ft. Phosphorus 10 µg/L. Chlorophyll-a 3.3 µg/L. TSI 41. The letter is not a swimming clearance.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 10.5 ft | Not graded |
| Phosphorus | 10 µg/L | Not graded |
| Chlorophyll-a (Algae) | 3.3 µg/L | Good |
| Trophic State Index (TSI) | 41 | Mesotrophic |
Moderate nutrients, good water quality
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 52 ft |
| Surface Area | 269 acres |
| Public Access | Yes |
Fish Species
Click a species to see every graded lake where it is documented.
Fishing Au Sable Lake
Water Quality Trend: → Stable
Based on 3 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↑ Improving | +0.718 m/yr | 3 |
| Phosphorus | → Stable | -0.06 µg/L/yr | 3 |
| Chlorophyll-a | ↓ Declining | +0.23 µg/L/yr | 3 |
County Ranking
Ranked #2 of 2 lakes in Ogemaw County
Nearby Lakes in Ogemaw County
Frequently asked questions about Au Sable Lake
Where is Au Sable Lake?
- Au Sable Lake is a lake in Ogemaw County, Michigan. LakeQuality grades it A for nutrients and algae. The letter is not a swimming clearance.
What is the water quality grade for Au Sable Lake?
- Au Sable Lake in Ogemaw County, Michigan has a water quality grade of A (Excellent). Water clarity: 10.5 ft visibility. Phosphorus: 10 µg/L. Chlorophyll-a (algae): 3.3 µg/L. Maximum depth: 52 ft. Surface area: 268.7 acres.
Is Au Sable Lake safe to swim in?
- The A is nutrients and algae, not a swimming clearance. Check local advisories before you swim.
How deep is Au Sable Lake?
- Au Sable Lake has a maximum depth of 52 feet. The lake covers 268.7 acres.
What fish are in Au Sable Lake?
- Fish species found in Au Sable Lake include Bluegill, Bluntnose minnow, Iowa darter, Johnny darter, Largemouth bass, Least darter, Northern longear sunfish, Pumpkinseed, Rock bass, Western banded killifish, Yellow perch. Au Sable Lake is located in Ogemaw County, Michigan.
Explore Au Sable Lake across LakeQuality
Fish species and top-graded lakes across Michigan
Fish species and best lakes in Ogemaw County
Species activity outlook by water temperature and season
Where to stay at Michigan's top lakes, each with its grade
Moderate nutrients, good water quality
Michigan's cleanest and most-polluted lakes, ranked
More Michigan Lake Rankings
Other Grade A Lakes in Michigan
Mesotrophic Lakes in Michigan
Where this data comes from
34 measurements from 1 monitoring station, 2022–2023. Retrieved from the EPA Water Quality Portal on 2026-08-26.
Collected and reported by
- Michigan EGLE - MiCorps
21MICH_MICORPS34 samples · 2022–2023
Analytical methods
- Phosphorus by Colorimetry
- 445.0 ~ EPA; Chlorophyll and Pheophytin in Algae by Fluorescence
Monitoring station identifiers (1)
Grade thresholds from the EPA National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See how grades are calculated and data sources.