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LakeQuality

Miller Lake

D
Grade D — Nutrient-rich
Nutrient-rich · #18 of 22 lakes in the county · 1.8 ft clear · Eutrophic · from C
Limited DataEutrophic

Miller Lake in Carlton County, Minnesota has a water quality grade of D (Nutrient-rich). Water clarity: 1.8 ft visibility. Phosphorus: 57.5 µg/L. Chlorophyll-a (algae): 9 µg/L.

Clarity
1.8 ft
Typical in July
71°F
Max depth
~33 ft est.
Type
Eutrophic
Trend
Improving
Public access
Yes

Grade D measures nutrients and algae, not whether this is a good place for a cabin trip. Cabins and rentals near Miller Lake

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CLac Lake9.5 ft clear · Carlton CountyView →
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Miller Lake is a productive, nutrient-rich eutrophic lake in Carlton County, Minnesota with an estimated average depth of about 33 feet. Water quality is graded D based on 2 sampling years through 2024. Overall water quality is improving over recent sampling years. Limited fish-species data available. Public access is available. Compared to the 21 other monitored lakes in Carlton County, Miller Lake ranks #18 for water quality.

Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2024-10-17. Grade methodology: LakeGrade methodology.

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Swimming Safety

Grade only

Limited data

Based on clarity and algae grades from past sampling — we do not hold live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.

Nutrients and algae run higher than average — check local advisories before swimming, and skip the water if you see scum

Compare the safest swimming lakes near Duluth

Get alerts for Miller Lake

Water Quality Grade: D (Nutrient-rich)

Very murky, less than 1.8 ft of visibility. Phosphorus level: 57.5 µg/L. Chlorophyll-a: 9 µg/L. Trophic State Index: 61.

MetricValueGrade
Water Clarity (Secchi Depth)1.8 ftNot graded
Phosphorus57.5 µg/LPoor
Chlorophyll-a (Algae)9 µg/LFair
Trophic State Index (TSI)61Eutrophic

High nutrients, frequent algae, reduced clarity

Where to stay near Miller Lake

Compare lakeside cabins, hotels, and vacation rentals near Miller Lake in Carlton 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. The water-quality grade measures nutrients and algae, not lodging — cabins and rentals around Miller Lake are listed below.

Top-rated places to stay near Miller 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

Miller Lake typically sits around 71°F at the surface in July. Summer average is about 69°F. Usually warmest in Jul (about 71°F) and coldest in Oct (about 43°F). These are typical values by month — not a live reading.

Jan
Feb
Mar
Apr
May
Jun
66°
Jul
71°
Aug
Sep
Oct
43°
Nov
Dec

Typical surface water temperature by month, from 13 field readings (20112019) via the EPA Water Quality Portal. See the full Miller Lake water temperature breakdown →

Lake Details

CharacteristicValue
Maximum Depth~33 ft est.
Average Depth~10 ft est.
Public AccessYes

Depth marked “est.” is a modeled maximum from GLOBathy (Khazaei et al. 2022, CC0), not a measured survey. Minnesota has not published bathymetry for Miller Lake.

Lake Size & Watershed

Watershed (drainage) area
1 sq mi
Surface area
151 acres
Shoreline
2.1 mi
Elevation
1,293 ft

Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS). Mean depth here is modelled, not surveyed — HydroLAKES v1.0 estimates lake depth from surrounding terrain rather than from soundings. Treat it as an approximation, and prefer a state bathymetric survey where one exists.

Fishing Miller Lake

DNR Reports & Resources

Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Miller Lake. 2 reports 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 Improving+2.237 m/yr5
Phosphorus Declining+68.55 µg/L/yr4
Chlorophyll-a Improving-0.9 µg/L/yr5
See year-by-year chart →

EPA Impairment Status

Miller Lake is officially listed as impaired under Clean Water Act §303(d) in the 2019 EPA reporting cycle.

Causes of impairment

Mercury

Source: EPA ATTAINS assessment unit FDL_112 · Official waterbody report · Matched by proximity (0.01 km)

County Ranking

Ranked #18 of 22 lakes in Carlton County

Nearby Lakes With Higher Grades

Miller Lake holds Grade D. 3 nearby lakes hold higher nutrient-and-algae grades — useful for a swim day, not a reason to skip lodging here.

Nearby Lakes in Carlton County

Frequently asked questions about Miller Lake

What is the water quality grade for Miller Lake?

Miller Lake in Carlton County, Minnesota has a water quality grade of D (Nutrient-rich). Water clarity: 1.8 ft visibility. Phosphorus: 57.5 µg/L. Chlorophyll-a (algae): 9 µg/L.

Is Miller Lake safe to swim in?

Nutrients and algae run higher than average — check local advisories before swimming, and skip the water if you see scum. Miller Lake has a water quality grade of D (Nutrient-rich). Algae concentration (chlorophyll-a) is 9 µg/L. Always check local health department advisories before swimming.

What is the water temperature of Miller Lake?

Miller Lake typically sits around 71°F at the surface in July, from 13 EPA Water Quality Portal field readings (2011–2019). That is a typical value for the month, not a live reading.

How deep is Miller Lake?

No published bathymetric survey covers Miller Lake, so its depth has not been measured. The HydroLAKES global model estimates an average depth of about 33 feet, but that is a modelled estimate derived from surrounding terrain rather than a measurement on the water, so treat it as approximate.

Where this data comes from

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

Collected and reported by

  • Fond du Lac Band of Chippewa (MN)FONDULAC_WQX60 samples · 2020–2024

Analytical methods

  • Phosphorus by Two Reagent Colorimetry
  • Phosphorus by Colorimetry
  • 10200 H 2 ~ Chlorophyll a-b-c Determination by spectrophotometer
  • 10200 H ~ Chlorophyll a-b-c Determination
  • Color, APHA Platinum-Cobalt
  • For determination of Copper by the Bicinchoninate 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