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LakeQuality

Clear Lake

NR
Not yet rated
11 ft clear · Mesotrophic · 113 acres
Limited DataMesotrophic

Clear Lake in St. Louis County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 11 ft visibility. Maximum depth: 24 ft. Surface area: 112.62 acres.

Clarity
11 ft
Typical in August
73°F
Max depth
24 ft
Area
113 acres
Trend
Declining
Public access
Yes
Ice-out
Apr 26
Open water
209 days

Next lake in St. Louis County

BEagles Nest Lake15.5 ft clear · St. Louis CountyView →
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Why Clear 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 Clear 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.

Clear Lake is a 113-acre lake in St. Louis County, Minnesota with a maximum depth of 24 feet. Overall water quality is declining over recent sampling years. The lake supports 9 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 2024-09-29. Grade methodology: LakeGrade methodology.

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Swimming Safety

Not rated

Limited data

Not rated for swimming — there is not enough monitoring data to judge this lake

Compare the safest swimming lakes near Ely

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Water quality measurements for Clear Lake

These readings exist but do not meet the evidence bar for an A–F grade — see why.

Good clarity, visible to about 11 ft. Trophic State Index: 43.

MetricValueGrade
Water Clarity (Secchi Depth)11 ftNot graded
PhosphorusNo recent samples
Chlorophyll-a (Algae)No recent samples
Trophic State Index (TSI)43Mesotrophic

Moderate nutrients, good water quality

Where to stay near Clear Lake

Compare lakeside cabins, hotels, and vacation rentals near Clear 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 Clear 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 →

Water Temperature

Clear Lake typically sits around 73°F at the surface in August. Summer average is about 73°F. Usually warmest in Jul (about 73°F) and coldest in Sep (about 68°F). These are typical values by month — not a live reading.

Jan
Feb
Mar
Apr
May
Jun
Jul
73°
Aug
73°
Sep
68°
Oct
Nov
Dec

Typical surface water temperature by month, from 12 field readings (20222024) via the EPA Water Quality Portal. See the full Clear Lake water temperature breakdown →

Lake Details

CharacteristicValue
Maximum Depth24 ft
Surface Area113 acres
Shoreline Length3.1 mi
Littoral Zone86%
Public AccessYes

Lake Size & Watershed

Watershed (drainage) area
1 sq mi
Elevation
1,490 ft

Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).

Recreation & Access

1
Boat Landings
Yes
Public Access
  • West Robinson LakePublic

Fish Species

Click a species to see every graded lake where it is documented.

Fishing Clear Lake

DNR Fisheries Survey Summary

2 surveys on file from MN DNR Fisheries. Most recent: 2002-06-24 (Standard Survey).

Top Species by Catch Rate

SpeciesAvg CPUEAvg Weight
Yellow Perch22.940.12 lb
Bluegill6.600.2 lb
Black Crappie3.790.23 lb
White Sucker3.502.38 lb
Northern Pike2.194.75 lb
Walleye1.154.28 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.

Yellow Perch

10 fish · 16 in · 2002-06-24
530123456

Bluegill

228 fish · 39 in · 2002-06-24
81410trophy 103456789

Black Crappie

60 fish · 410 in · 2002-06-24
30150trophy 1045678910

White Sucker

66 fish · 1220 in · 2002-06-24
22110121314151617181920

From the 2002-06-24 survey

Clear Lake is in Ecological Lake Class 13, which consists of 84 lakes in northeast Minnesota that are small, shallow, and have very soft (unmineralized) water. Clear Lake ranks as mesotrophic according to Carlson's Trophic State Index.Clear Lake has no inlets or outlet. Lake bottom substrates along the shoreline are…

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 Clear Lake. 1 report on file.

These links open on the official state DNR websites (Wisconsin DNR survey PDFs · Minnesota DNR LakeFinder).

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

MetricTrendChange/YearYears
Water Clarity Declining-0.289 m/yr5
See year-by-year chart →

Ice Season

Historical ice data from Minnesota DNR (17 observations).

Typical Ice-Out
Apr 26
Typical Ice-In
Nov 21

Estimated open water season: 209 days

EarliestLatest
Ice-Out2010-03-30 (2010)2022-05-09 (2022)
Ice-In2002-11-05 (2002)2024-11-29 (2024)

Most recent ice-out: 2025-05-01

EPA Impairment Status

Clear Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 4A).

Causes of impairment

Mercury

A Total Maximum Daily Load (TMDL) plan has been approved.

Source: EPA ATTAINS assessment unit MN69-0217-00 · Official waterbody report · Matched by proximity (0.97 km)

Graded lakes near Clear Lake

Clear Lake has no grade, but these lakes within a short drive do.

Nearby Lakes in St. Louis County

Frequently asked questions about Clear Lake

What is the water quality grade for Clear Lake?

Clear Lake in St. Louis County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 11 ft visibility. Maximum depth: 24 ft. Surface area: 112.62 acres.

Is Clear Lake safe to swim in?

Not rated for swimming — there is not enough monitoring data to judge this lake. Clear Lake is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.

What is the water temperature of Clear Lake?

Clear Lake typically sits around 73°F at the surface in August, from 12 EPA Water Quality Portal field readings (2022–2024). That is a typical value for the month, not a live reading.

How deep is Clear Lake?

Clear Lake has a maximum depth of 24 feet. The lake covers 112.62 acres.

What fish are in Clear Lake?

Fish species found in Clear Lake include black crappie, bluegill, largemouth bass, northern pike, rock bass, smallmouth bass, walleye, white sucker, yellow perch. Clear Lake is located in St. Louis County, Minnesota.

When does Clear Lake thaw?

Clear Lake typically has ice-out around Apr 26. Ice typically forms around Nov 21. The open water season is approximately 209 days.

Are there boat ramps on Clear Lake?

Clear Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include West Robinson Lake. Public access is listed as yes.

Mesotrophic Lakes in Minnesota

Where this data comes from

21 measurements from 1 monitoring station, 2020–2024. Retrieved from the EPA Water Quality Portal on 2026-08-02.

Collected and reported by

  • Minnesota Pollution Control Agency - Ambient Surface WaterMNPCA21 samples · 2020–2024

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

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

Ice data from Minnesota DNR Climate