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LakeQuality

Mudro Lake

NR
Not yet rated
94 acres
Limited Data

Mudro Lake in St. Louis County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Maximum depth: 76 ft. Surface area: 93.64 acres.

Typical in August
49°F
Max depth
76 ft
Area
94 acres
Public access
No

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Why Mudro 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 Mudro Lake, no nutrient or algae measurement meets the evidence bar (at least 3 samples within 10 years).

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.

Mudro Lake is a 94-acre lake in St. Louis County, Minnesota with a maximum depth of 76 feet. The lake supports 7 documented fish species including burbot, cisco species, and northern pike. No public access — the lake is private or restricted.

Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-10-29. 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

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Water quality measurements for Mudro Lake

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

No clarity data.

MetricValueGrade
Water Clarity (Secchi Depth)No recent samples
PhosphorusNo recent samples
Chlorophyll-a (Algae)No recent samples

Where to stay near Mudro Lake

Compare lakeside cabins, hotels, and vacation rentals near Mudro 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 Mudro Lake

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Water Temperature

Mudro Lake typically sits around 49°F at the surface in August. Summer average is about 49°F. Usually warmest in Jul (about 50°F) and coldest in Jun (about 47°F). These are typical values by month — not a live reading.

Jan
Feb
Mar
Apr
May
Jun
47°
Jul
50°
Aug
49°
Sep
Oct
Nov
Dec

Typical surface water temperature by month, from 162 field readings (20192025) via the EPA Water Quality Portal. See the full Mudro Lake water temperature breakdown →

Lake Details

CharacteristicValue
Maximum Depth76 ft
Surface Area94 acres
Shoreline Length3.5 mi
Littoral Zone26%
Public AccessNo

Lake Size & Watershed

Watershed (drainage) area
1 sq mi
Elevation
1,368 ft

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

Fish Species

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

Fishing Mudro Lake

EPA Impairment Status

Mudro 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 MN69-0078-00 · Official waterbody report

Nearby Lakes in St. Louis County

Frequently asked questions about Mudro Lake

What is the water quality grade for Mudro Lake?

Mudro Lake in St. Louis County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Maximum depth: 76 ft. Surface area: 93.64 acres.

Is Mudro Lake safe to swim in?

Not rated for swimming — there is not enough monitoring data to judge this lake. Mudro 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 Mudro Lake?

Mudro Lake typically sits around 49°F at the surface in August, from 162 EPA Water Quality Portal field readings (2019–2025). That is a typical value for the month, not a live reading.

How deep is Mudro Lake?

Mudro Lake has a maximum depth of 76 feet. The lake covers 93.64 acres.

What fish are in Mudro Lake?

Fish species found in Mudro Lake include burbot, cisco species, northern pike, smallmouth bass, tullibee (cisco), walleye, white sucker. Mudro Lake is located in St. Louis County, Minnesota.

Where this data comes from

1 measurement 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 WaterMNPCA1 sample · 2025

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