Perch Lake
St. Louis County, Minnesota100 acresView mapDirections
Minnesota PCA publishes the water-quality measurements for Perch Lake. Here is what has been measured.
- Impaired · Mercury
- 13 ft max depth
- Public access
- Limited data
Perch Lake in St. Louis County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 6.6 ft visibility. Phosphorus: 21 µg/L. Chlorophyll-a (algae): 11.5 µg/L. Maximum depth: 13 ft. Surface area: 100.14 acres.
Perch Lake is a 100-acre lake in St. Louis County, Minnesota with a maximum depth of 13 feet. The lake supports 6 documented fish species including bluegill, hybrid sunfish, and northern pike. Public access is available.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-08-16. Methodology: how these readings are compared.
What Perch Lake is good for
From access and monitoring records, not editorial picks.
- Fishing6 species recorded
Swimming conditions
No readingLimited data
Nutrient and algae readings are not a swimming clearance. Perch Lake is listed impaired under Clean Water Act §303(d) (IR 5) for mercury. Check local advisories before you swim.
Whether Perch Lake is safe to swim in today is a call for the Minnesota Pollution Control Agency and the Minnesota DNR and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Perch Lake
These are the measurements Minnesota PCA publishes for Perch Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Murky, only visible to about 6.6 ft. Phosphorus 21 µg/L. Chlorophyll-a 11.5 µg/L. TSI 51.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 6.6ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 21µg/L | Measured, not scored The nutrient that most limits algae growth in freshwater. More phosphorus, more algae potential. |
| Chlorophyll-a (algae) | 11.5µg/L | Measured, not scored The green pigment in algae — a direct measure of how much algae is in the water. |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 51 | Eutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
High nutrients, frequent algae, reduced clarity
Ask about Perch Lake
Answers come straight from the public measurements and survey records on this page.
Lake Details
Max depth
13 ft
Surface area
100 acres
Shoreline
3.3 mi
Littoral zone
100%
Share shallower than 15 ft
Public access
Yes
Listed by Minnesota PCA
Lake Size & Watershed
Watershed (drainage) area
1 sq mi
HydroLAKES / HydroSHEDS
Elevation
1,440 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Stays via Stay22
Stays near Perch Lake
Compare lakeside cabins, hotels, and vacation rentals near Perch 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 Perch Lake
Prices for Oct 9–11, 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 Minnesota’s top lakes →
Follow Perch Lake’s readings
Email me when new measurements post for this lake. Updates stay free.
Or email
Fish Species
Click a species to see every lake where it is documented.
Fishing Perch Lake
EPA Impairment Status
Perch Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5).
Causes of impairment
Designated uses not supporting: Fish consumption.
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit MN69-0058-00 · Official waterbody report
Regulated Pollution Sources Nearby
1 EPA-permitted facility operate within about 5 miles of Perch Lake under Clean Water Act (NPDES) discharge permits. 1 facility has a reported Clean Water Act violation in the past three years.
- Babbitt WwtpBabbitt · 4.3 mi away · NPDES MN0020656Recent violation
Facilities permitted to discharge under the Clean Water Act within ~5 miles; proximity does not by itself mean a facility affects this lake. Source: EPA ECHO (ICIS-NPDES), as of 2026-07.
Nearby Lakes in St. Louis County
Frequently asked questions about Perch Lake
Where is Perch Lake?
- Perch Lake is a lake in St. Louis County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Perch Lake?
- Perch Lake in St. Louis County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 6.6 ft visibility. Phosphorus: 21 µg/L. Chlorophyll-a (algae): 11.5 µg/L. Maximum depth: 13 ft. Surface area: 100.14 acres.
Is Perch Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Perch Lake is listed impaired under Clean Water Act §303(d) (IR 5) for mercury. Check local advisories before you swim.
How deep is Perch Lake?
- Perch Lake has a maximum depth of 13 feet. The lake covers 100.14 acres.
What fish are in Perch Lake?
- Fish species found in Perch Lake include bluegill, hybrid sunfish, northern pike, walleye, white sucker, yellow perch. Perch Lake is located in St. Louis County, Minnesota.
Can I fish at Perch Lake?
- Public access to Perch Lake is listed as yes on the lake record. Seasons, size and bag limits, and whether you need a license are set by Minnesota's fish and wildlife agency, so check its current regulations before you go.
Explore Perch Lake across LakeQuality
Fish species and the cleanest 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 readings
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 lakes, ranked on agency measurements
More lakes in Minnesota
State Parks Near Perch Lake
Other Lakes in Minnesota
Eutrophic Lakes in Minnesota
Where this data comes from
9 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
MNPCA9 samples · 2025
Analytical methods
- Field measurement/observation, generic method
- Phosphorus by Two Reagent Colorimetry
- 10200 H ~ Chlorophyll a-b-c Determination
Monitoring station identifiers (1)
EPA condition classes from the National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See where the data comes from and data sources.
Other records on this page
Impairment status from EPA ATTAINS 303(d) database
Regulated discharger data from EPA ECHO (ICIS-NPDES)
Lake size & watershed from HydroLAKES (HydroSHEDS)
Lake details from Minnesota DNR LakeFinder