Skip to main content
LakeQuality
B

Fenske Lake

St. Louis County, MinnesotaLimited DataMesotrophic

Fenske Lake carries a solid B grade — strong on most parameters, with measurements that hold up well across the summer season.

Mesotrophic conditions dominate at Fenske Lake: enough nutrients for a healthy fishery, not so much that algal blooms become a chronic problem. Fenske Lake reaches 43 ft at its deepest point — typical for Minnesota mid-sized lakes, with seasonal stratification but limited cold-water refuge. At 108 acres, Fenske Lake fits the Minnesota median for monitored lakes, with 4.6 miles of shoreline. Fenske Lake ranks 63 of 187 in St. Louis County — solidly in the upper half of the local distribution.

No invasive species are currently listed at Fenske Lake — the lake remains off the Minnesota infested-waters roster. The fishery is bass-led, with 8 documented species across the lake's records. A documented public access point at Fenske Lake makes the lake usable for shore fishing, paddle craft, and trailered boats. Monitoring depth is thin here: the LakeGrade rubric is applied to a small number of sample years, and the grade will be revised as more data accumulates.

Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2023-09-03. Grade methodology: LakeGrade methodology.

Reviewed by LakeQuality Editorial Team · Updated

Track Fenske Lake

Subscribe for LakeQuality updates by email. No spam, unsubscribe anytime.

Swimming Safety

Good for swimming, clear water with low algae levels

Water Quality Grade: B, Good

Good clarity, visible to about 11.5 ft. Trophic State Index: 42.

MetricValueGrade
Water Clarity (Secchi Depth)11.5 ftB
PhosphorusNo data
Chlorophyll-a (Algae)No data
Trophic State Index (TSI)42Mesotrophic

Moderate nutrients, good water quality

Lake Details

CharacteristicValue
Maximum Depth43 ft
Surface Area108.43 acres
Shoreline Length4.6 mi
Littoral Zone58%
Public AccessYes

Fish Species

black crappie,bluegill,largemouth bass,northern pike,smallmouth bass,tullibee (cisco),white sucker,yellow perch

Click a species to see all Minnesota and Wisconsin lakes where it is found.

→ Best fishing times for Fenske Lake (14-day solunar calendar)

→ Is it safe to eat fish from Fenske Lake? (mercury & PFAS guide)

Fenske Lake fishing regulations (limits, seasons, special rules)

Water Quality Trend: Declining

Based on 5 years of monitoring data (2020-2025).

MetricTrendChange/YearYears
Water Clarity Declining-0.199 m/yr5
See year-by-year chart →

Location

Loading map…

County Ranking

Ranked #63 of 187 lakes in St. Louis County

Cleaner Lakes Within 30 Miles

Fenske Lake holds Grade B. One nearby lake has a higher grade.

Nearby Lakes in St. Louis County

DNR Fisheries Survey Summary

6 surveys on file from MN DNR Fisheries. Most recent: 2017-07-24 (Standard Survey).

Top Species by Catch Rate

SpeciesAvg CPUEAvg Weight
Bluegill9.870.17 lb
Tullibee (Cisco)2.030.53 lb
Northern Pike1.363.87 lb
White Sucker1.163.2 lb
Black Crappie1.040.5 lb
Largemouth Bass1.010.21 lb

CPUE = catch per unit effort, averaged across surveys (excludes juvenile shoreline seining). Higher CPUE = more abundant in standardized sampling.

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

143 fish · 38 in · 2017-07-24
40200345678

Tullibee (Cisco)

1 fish · 99 in · 2017-07-24
109

Northern Pike

22 fish · 1540 in · 2017-07-24
320trophy 3616182022242628303234363840

White Sucker

1 fish · 2121 in · 2017-07-24
1021

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…

Source: MN DNR LakeFinder Fisheries Lake Survey

DNR Reports & Resources

Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Fenske Lake. 3 reports on file.

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

Mercury

Source: EPA ATTAINS assessment unit MN69-0085-00 · Official waterbody report

Data Sources

Water quality data from the EPA Water Quality Portal

Impairment status from EPA ATTAINS 303(d) database

Grading methodology based on Metropolitan Council standards

Lake details from Minnesota DNR LakeFinder

Most recent sample: 2023-09-03

Monitoring stations: 1