Fenske Lake
St. Louis County, Minnesota108 acresView mapDirections
Minnesota PCA publishes the water-quality measurements for Fenske Lake. Here is what has been measured.
- Oligotrophic
- Impaired · Mercury
- 43 ft max depth
- Public access
- Limited data
Fenske Lake in St. Louis County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 11.5 ft visibility. Phosphorus: 11 µg/L. Chlorophyll-a (algae): 1.6 µg/L. Maximum depth: 43 ft. Surface area: 108.43 acres.
Minnesota DNR's Standard Survey on July 24, 2017 caught 2.17 northern pike per gill net at Fenske Lake. Length samples in the latest survey that recorded them ran 15–40 inches. DNR survey details →
Fenske Lake is a 108-acre cold, clear oligotrophic lake in St. Louis County, Minnesota with a maximum depth of 43 feet. Overall water quality is declining over recent sampling years. The lake supports 8 documented fish species including black crappie, bluegill, and largemouth bass. Public access is available with 1 public boat landing. Compared to the 67 other monitored lakes in St. Louis County, Fenske Lake ranks #24 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-09-30. Methodology: how these readings are compared.
What Fenske Lake is good for
From access and monitoring records, not editorial picks.
- Clear water11.5 ft of visibility
- Boat launch1 documented ramp
- Fishing8 species recorded
- Camping1 public campground nearby
- Deep water43 ft surveyed max depth
Swimming conditions
Readings onlyLimited data
Based on clarity and algae readings from past sampling — there is no live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
Nutrient and algae readings are not a swimming clearance. Fenske Lake is listed impaired under Clean Water Act §303(d) (IR 5) for mercury. Check local advisories before you swim.
Whether Fenske 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 Fenske Lake
These are the measurements Minnesota PCA publishes for Fenske Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Good clarity, visible to about 11.5 ft. Phosphorus 11 µg/L. Chlorophyll-a 1.6 µg/L. TSI 39.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 11.5ft | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 11µg/L | Good GoodFairPoor |
| Chlorophyll-a (algae) | 1.6µg/L | Good GoodFairPoor |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 39 | Oligotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Low nutrients, clear water. No reading is a swimming clearance.
Ask about Fenske Lake
Answers come straight from the public measurements and survey records on this page.
Water Temperature
Fenske Lake typically sits around 54°F at the surface in September. Summer average is about 56°F. Usually warmest in Aug (about 58°F) and coldest in Jun (about 52°F). These are typical values by month — not a live reading.
Column height runs from this lake’s coldest month (52°F) to its warmest (58°F).
Typical surface water temperature by month, from 69 field readings (2024–2025) via the EPA Water Quality Portal. See the full Fenske Lake water temperature breakdown →
Minnesota DNR's Standard Survey on July 24, 2017 caught 2.17 northern pike per gill net at Fenske Lake. Length samples in the latest survey that recorded them ran 15–40 inches.
A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Fenske Lake’s water-quality measurements separately, and the water-quality trend over 6 years of monitoring is declining. Catch rate is not a swim clearance and is not a weekly bite report.
DNR Fisheries Survey Summary
6 surveys on file from MN DNR Fisheries. Most recent: 2017-07-24 (Standard Survey).
6 surveys on file · most recent 2017-07-24 (Standard Survey)
| Species | Catch rate (CPUE) | Size | Avg weight |
|---|---|---|---|
| Bluegill | 9.87 | 3–8 in 2017-07-24 | 0.17 lb |
| Tullibee (Cisco) | 2.03 | 9 in 2017-07-24 | 0.53 lb |
| Northern Pike | 1.36 | 15–40 in 2017-07-24 | 3.87 lb |
| White Sucker | 1.16 | 21 in 2017-07-24 | 3.2 lb |
| Black Crappie | 1.04 | 7–10 in 2017-07-24 | 0.5 lb |
| Largemouth Bass | 1.01 | 5–6 in 2017-07-24 | 0.21 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.
Bluegill
Tullibee (Cisco)
Northern Pike
White Sucker
From the 2017-07-24 survey
Fenske Lake is located approximately 8 miles N of Ely within the Superior National Forest. There are several cabins around the lake and a small resort is located near the NW corner. The USFS operates a campround near the NW corner as well. There is a gravel boat ramp near the campground off CR 116 (Echo Trail) for…
DNR Reports & Resources
Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Fenske Lake. 3 reports on file.
These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).
- —Fisheries Lake Survey — FenskeFisheries Lake Survey · MN DNR LakeFinder
- —Aquatic Plant Report — Fenske (1515)Aquatic Plant Report · MN DNR LakeFinder
- —Public Water Access Sites — FenskePublic Water Access Sites · MN DNR LakeFinder
Lake Details
Max depth
43 ft
Surface area
108 acres
Shoreline
4.6 mi
Littoral zone
58%
Share shallower than 15 ft
Public access
Yes
Listed by Minnesota PCA
Lake Size & Watershed
Watershed (drainage) area
1 sq mi
HydroLAKES / HydroSHEDS
Elevation
1,447 ft
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Recreation & Access
- Fenske LakePublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Public campgrounds near Fenske Lake
- Fenske Lake Campground0.6 kmReserve
Nearest public campgrounds in the USGS National Map inventory, within about 3 miles. An empty list means USGS records no campground that close, which is not the same as camping being unavailable. Where the source gives an official reservation link, it is used; the cabin and hotel search does not cover campsites. More camping lakes
Stays via Stay22
Stays near Fenske Lake
Compare lakeside cabins, hotels, and vacation rentals near Fenske 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 Fenske 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 Fenske 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 Fenske Lake
Water Quality Trend: Worsening
Based on 6 years of monitoring (2020–2025).
Water clarity
Worsening6 years
EPA Impairment Status
Fenske 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.
Source: EPA ATTAINS assessment unit MN69-0085-00 · Official waterbody report
Nearby Lakes in St. Louis County
Frequently asked questions about Fenske Lake
Where is Fenske Lake?
- Fenske 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 Fenske Lake?
- Fenske Lake in St. Louis County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Water clarity: 11.5 ft visibility. Phosphorus: 11 µg/L. Chlorophyll-a (algae): 1.6 µg/L. Maximum depth: 43 ft. Surface area: 108.43 acres.
Is Fenske Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Fenske Lake is listed impaired under Clean Water Act §303(d) (IR 5) for mercury. Check local advisories before you swim.
What is the water temperature of Fenske Lake?
- Fenske Lake typically sits around 54°F at the surface in September, from 69 EPA Water Quality Portal field readings (2024–2025). That is a typical value for the month, not a live reading.
How deep is Fenske Lake?
- Fenske Lake has a maximum depth of 43 feet. The lake covers 108.43 acres.
What fish are in Fenske Lake?
- Fish species found in Fenske Lake include black crappie, bluegill, largemouth bass, northern pike, smallmouth bass, tullibee (cisco), white sucker, yellow perch. Fenske Lake is located in St. Louis County, Minnesota.
What did the DNR fisheries survey find at Fenske Lake?
- Minnesota DNR's Standard Survey on July 24, 2017 caught 2.17 northern pike per gill net at Fenske Lake. Length samples in the latest survey that recorded them ran 15–40 inches. A DNR fisheries survey reports fish abundance and catch rates, not water quality. LakeQuality shows Fenske Lake’s water-quality measurements separately, and the water-quality trend over 6 years of monitoring is declining. Catch rate is not a swim clearance and is not a weekly bite report.
Are there boat ramps on Fenske Lake?
- Fenske Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Fenske Lake. Public access is listed as yes.
Can I fish at Fenske Lake?
- Fenske 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.
Are there campgrounds on Fenske Lake?
- Fenske Lake has 1 public campground from USGS The National Map within 5 km, including Fenske Lake Campground. This is a location join, not a booking. Cabins and hotels are listed separately; campsite reservations use the official link when the source provides one.
Explore Fenske 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 Fenske Lake
Other Lakes in Minnesota
Oligotrophic Lakes in Minnesota
Where this data comes from
48 measurements from 1 monitoring station, 2021–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA48 samples · 2021–2025
Analytical methods
- Field measurement/observation, generic method
- Phosphorus by 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
Lake size & watershed from HydroLAKES (HydroSHEDS)
Lake details from Minnesota DNR LakeFinder
Named boat-access points from the USGS National Boat Ramps inventory
Public campgrounds from USGS The National Map Structures, within about 3 miles