Susan Lake
St. Louis County, Minnesota276 acresView mapDirections
Minnesota PCA publishes the water-quality measurements for Susan Lake. Here is what has been measured.
- Impaired · Mercury
- 10 ft max depth
- Public access
- Limited data
Susan Lake in St. Louis County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 3.6 ft visibility. Phosphorus: 32 µg/L. Chlorophyll-a (algae): 10.8 µg/L. Maximum depth: 10 ft. Surface area: 275.84 acres.
Minnesota DNR's Standard Survey on August 25, 2025 caught 4.67 walleye per gill net at Susan Lake. Length samples in the latest survey that recorded them ran 15–22 inches. DNR survey details →
Susan Lake is a 276-acre lake in St. Louis County, Minnesota with a maximum depth of 10 feet. The lake supports 7 documented fish species including black crappie, bluegill, and largemouth bass. Public access is available with 1 public boat landing.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2022-07-21. Methodology: how these readings are compared.
Susan Lake covers about 280 acres in St. Louis County. It has one public boat landing. If you are planning to stay, you can search lake houses and cabins around Susan Lake on Vrbo, or look for a hotel room near the lake on Booking.com or Expedia.
What Susan Lake is good for
From access and monitoring records, not editorial picks.
- Boat launch1 documented ramp
- Fishing7 species recorded
Swimming conditions
No readingLimited data
Nutrient and algae readings are not a swimming clearance. Susan Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury. Check local advisories before you swim.
Whether Susan 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 Susan Lake
These are the measurements Minnesota PCA publishes for Susan 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 3.6 ft. Phosphorus 32 µg/L. Chlorophyll-a 10.8 µg/L. TSI 56.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 3.6ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 32µg/L | Measured, not scored The nutrient that most limits algae growth in freshwater. More phosphorus, more algae potential. |
| Chlorophyll-a (algae) | 10.8µg/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. | 56 | Eutrophic OligotrophicMesotrophicEutrophicHypereutrophic |
High nutrients, frequent algae, reduced clarity
Ask about Susan Lake
Answers come straight from the public measurements and survey records on this page.
Minnesota DNR's Standard Survey on August 25, 2025 caught 4.67 walleye per gill net at Susan Lake. Length samples in the latest survey that recorded them ran 15–22 inches.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Susan Lake’s water-quality measurements separately. Catch rate is not a swim clearance and is not a weekly bite report.
DNR Fisheries Survey Summary
5 surveys on file from MN DNR Fisheries. Most recent: 2025-08-25 (Standard Survey).
5 surveys on file · most recent 2025-08-25 (Standard Survey)
| Species | Catch rate (CPUE) | Size | Avg weight |
|---|---|---|---|
| Yellow Perch | 7.25 | 6–12 in 2025-08-25 | 0.42 lb |
| Walleye | 4.08 | 15–22 in 2025-08-25 | 1.48 lb |
| Bluegill | 1.88 | 1–9 in 2025-08-25 | 0.41 lb |
| Northern Pike | 1.45 | 14–24 in 2025-08-25 | 1.57 lb |
| Pumpkinseed | 1.23 | 4 in 2025-08-25 | 0.23 lb |
| White Sucker | 1.12 | 9–17 in 1996-08-26 | 1.73 lb |
CPUE = catch per unit effort, fish caught per net per set in a standardised survey. It measures abundance, not size, and is not a weekly bite report.
Length Distributions
Number of fish caught at each inch class in the most recent survey that recorded lengths. Red dashed line marks an approximate trophy threshold for that species.
Yellow Perch
Walleye
Bluegill
Northern Pike
From the 2025-08-25 survey
Susan Lake is located approximately four miles north of Wakemup, Minnesota. This 275-acre lake has a maximum depth of 10 feet and dark tannin-stained water. A fisheries survey was completed in Susan Lake during the 2025 field season as part of a regular rotation of surveys in the International Falls Management Area.…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Susan Lake. 2 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — SusanFisheries Lake Survey · MN DNR LakeFinder
- —Public Water Access Sites — SusanPublic Water Access Sites · MN DNR LakeFinder
Lake Details
Max depth
10 ft
Surface area
276 acres
Shoreline
5.1 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
1,362 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Elbow Lake (South)Public
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Stays via Stay22
Stays near Susan Lake
Compare lakeside cabins, hotels, and vacation rentals near Susan 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 Susan Lake
Prices for Oct 9–11, 4 adults. Change dates on the map below.
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Planning a whole trip? See where to stay at Minnesota’s top lakes →
Follow Susan Lake’s readings
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Fish Species
Click a species to see every lake where it is documented.
Fishing Susan Lake
EPA Impairment Status
Susan Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 4A).
Causes of impairment
Designated uses not supporting: Fish consumption.
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit MN69-0741-00 · Official waterbody report
Nearby Lakes in St. Louis County
Frequently asked questions about Susan Lake
Where is Susan Lake?
- Susan 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 Susan Lake?
- Susan Lake in St. Louis County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 3.6 ft visibility. Phosphorus: 32 µg/L. Chlorophyll-a (algae): 10.8 µg/L. Maximum depth: 10 ft. Surface area: 275.84 acres.
Is Susan Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Susan Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury. Check local advisories before you swim.
How deep is Susan Lake?
- Susan Lake has a maximum depth of 10 feet. The lake covers 275.84 acres.
What fish are in Susan Lake?
- Fish species found in Susan Lake include black crappie, bluegill, largemouth bass, northern pike, pumpkinseed, walleye, yellow perch. Susan Lake is located in St. Louis County, Minnesota.
What did the DNR fisheries survey find at Susan Lake?
- Minnesota DNR's Standard Survey on August 25, 2025 caught 4.67 walleye per gill net at Susan Lake. Length samples in the latest survey that recorded them ran 15–22 inches. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Susan Lake’s water-quality measurements separately. Catch rate is not a swim clearance and is not a weekly bite report.
Are there boat ramps on Susan Lake?
- Susan Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Elbow Lake (South). Public access is listed as yes.
Can I fish at Susan Lake?
- Susan Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. 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 Susan Lake across LakeQuality
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Fish species and best lakes in St. Louis County
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Where this data comes from
5 measurements from 1 monitoring station, 2022. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA5 samples · 2022
Analytical methods
- Field measurement/observation, generic method
- Phosphorus by Colorimetry
- 10200 H ~ Chlorophyll a-b-c Determination
- 2130 B ~ Nephelometric Method
- 2120 B ~ Color in Water by Visual Comparison
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
Lake size & watershed from HydroLAKES (HydroSHEDS)
Lake details from Minnesota DNR LakeFinder
Named boat-access points from the USGS National Boat Ramps inventory