Foss Lake
Foss Lake in St. Louis County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 4 ft visibility. Maximum depth: 6 ft. Surface area: 36.48 acres.
- Clarity
- 4 ft
- Max depth
- 6 ft
- Area
- 36 acres
- Public access
- No
Next lake in St. Louis County
Why Foss Lake has no grade
We grade a lake only when its monitoring record clears the evidence bar: at least three phosphorus or chlorophyll-a samples in the last ten years, scored against EPA National Lakes Assessment thresholds for this lake’s ecoregion. For Foss Lake, the only measurement available is water clarity, which is not a water-quality indicator on its own — EPA's National Lakes Assessment does not grade clarity. Sampling here has recorded water clarity, but not phosphorus and algae (chlorophyll-a).
Not Rated is not an F. It is EPA Integrated Reporting Category 3 — insufficient information. The water here may be excellent or poor; nobody has measured enough of it to say. Everything below that has been measured is still reported on this page.
Sampling is run by MPCA and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
Foss Lake is a 36-acre lake in St. Louis County, Minnesota with a maximum depth of 6 feet. The lake supports 3 documented fish species including bluegill, northern pike, and yellow perch. No public access — the lake is private or restricted.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-08-27. Grade methodology: LakeGrade methodology.
Watch Foss Lake water quality
Subscribe for LakeQuality updates by email. No spam, unsubscribe anytime.
Swimming Safety
Not ratedLimited data
Not rated for swimming — there is not enough monitoring data to judge this lake
Water quality measurements for Foss Lake
These readings exist but do not meet the evidence bar for an A–F grade — see why.
Murky, only visible to about 4 ft. Trophic State Index: 57.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 4 ft | Not graded |
| Phosphorus | No recent samples | |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 57 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Where to stay near Foss Lake
Compare lakeside cabins, hotels, and vacation rentals near Foss Lake in St. Louis County, Minnesota — 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 Foss Lake
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 Minnesota’s top lakes →
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 6 ft |
| Surface Area | 36 acres |
| Shoreline Length | 1.1 mi |
| Littoral Zone | 100% |
| Public Access | No |
Lake Size & Watershed
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Fish Species
Click a species to see every graded lake where it is documented.
Fishing Foss Lake
Graded lakes near Foss Lake
Foss Lake has no grade, but these lakes within a short drive do.
Nearby Lakes in St. Louis County
Frequently asked questions about Foss Lake
What is the water quality grade for Foss Lake?
- Foss Lake in St. Louis County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 4 ft visibility. Maximum depth: 6 ft. Surface area: 36.48 acres.
Is Foss Lake safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Foss Lake is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.
How deep is Foss Lake?
- Foss Lake has a maximum depth of 6 feet. The lake covers 36.48 acres.
What fish are in Foss Lake?
- Fish species found in Foss Lake include bluegill, northern pike, yellow perch. Foss Lake is located in St. Louis County, Minnesota.
Explore Foss Lake across LakeGrade
Fish species and top-graded lakes across Minnesota
Fish species and best lakes in St. Louis County
Species activity outlook by water temperature and season
Top lakes and where to stay in the Lake Vermilion Area area
Where to stay at Minnesota's top lakes, each with its grade
Lakes in the Lake Superior Basin (MN+WI), ranked by water quality
Lakes in the Rainy Lake Watershed, ranked by water quality
Minnesota's cleanest and most-polluted lakes, ranked
More Minnesota Lake Rankings
State Parks Near Foss Lake
Other Lakes in Minnesota
Eutrophic Lakes in Minnesota
Where this data comes from
6 measurements from 1 monitoring station, 2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA6 samples · 2025
Analytical methods
- Field measurement/observation, generic method
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.
Other records on this page
Lake size & watershed from HydroLAKES (HydroSHEDS)
Lake details from Minnesota DNR LakeFinder