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LakeQuality

Heron Lake

NR
Not yet rated
1 ft clear · Eutrophic
Limited DataEutrophic

Heron Lake in Jackson County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 1 ft visibility. Phosphorus: 27 µg/L. Chlorophyll-a (algae): 53.4 µg/L.

Clarity
1 ft
Mean depth
~8 ft est.
Public access
Yes

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Why Heron 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 Heron Lake, no nutrient or algae measurement meets the evidence bar (at least 3 samples within 10 years). Sampling here has recorded water clarity, 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.

Heron Lake is a lake in Jackson County, Minnesota with an estimated average depth of about 8 feet. Limited fish-species data available. Public access is available with 1 public boat landing.

Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2023-08-03. 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 Heron Lake

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

Very murky, less than 1 ft of visibility. Phosphorus level: 27 µg/L. Chlorophyll-a: 53.4 µg/L. Trophic State Index: 66.

MetricValueGrade
Water Clarity (Secchi Depth)1 ftNot graded
Phosphorus27 µg/LNot graded
Chlorophyll-a (Algae)53.4 µg/LNot graded
Trophic State Index (TSI)66Eutrophic

High nutrients, frequent algae, reduced clarity

Where to stay near Heron Lake

Compare lakeside cabins, hotels, and vacation rentals near Heron Lake in Jackson 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 Heron Lake

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Lake Details

CharacteristicValue
Average Depth~8 ft est.
Public AccessYes

Depth marked “est.” is a modeled estimate from HydroLAKES, not a measured survey. Minnesota has not published bathymetry for Heron Lake.

Lake Size & Watershed

Watershed (drainage) area
4 sq mi
Surface area
289 acres
Mean depth (modeled estimate)
~8 ft est.
Shoreline
3.5 mi
Elevation
1,394 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.

Recreation & Access

1
Boat Landings
Yes
Public Access
  • Jack CreekPublic

Fishing Heron Lake

DNR Reports & Resources

Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Heron Lake. 1 report on file.

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

EPA Impairment Status

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

Causes of impairment

Nutrients (phosphorus, nitrogen)

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

Source: EPA ATTAINS assessment unit MN32-0057-02 · Official waterbody report · Matched by proximity (0.34 km)

Regulated Pollution Sources Nearby

2 EPA-permitted facilities operate within about 5 miles of Heron Lake under Clean Water Act (NPDES) discharge permits. 1 facility has a reported Clean Water Act violation in the past three years.

  • Heron Lake Bioenergy
    Heron Lake · 0.8 mi away · NPDES MN0067385
    Recent violation
  • Heron Lake
    Heron Lake · 1.4 mi away · NPDES MN0023655

Facilities permitted to discharge under the Clean Water Act within ~5 miles; proximity does not by itself mean a facility affects this lake. Source: EPA ECHO (ICIS-NPDES), as of 2026-07.

Graded lakes near Heron Lake

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

Nearby Lakes in Jackson County

Frequently asked questions about Heron Lake

What is the water quality grade for Heron Lake?

Heron Lake in Jackson County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 1 ft visibility. Phosphorus: 27 µg/L. Chlorophyll-a (algae): 53.4 µg/L.

Is Heron Lake safe to swim in?

Not rated for swimming — there is not enough monitoring data to judge this lake. Heron Lake is not rated for water quality — its monitoring record does not meet the evidence bar. Algae concentration (chlorophyll-a) is 53.4 µg/L. Always check local health department advisories before swimming.

How deep is Heron Lake?

No published bathymetric survey covers Heron Lake, so its depth has not been measured. The HydroLAKES global model estimates an average depth of about 8 feet, but that is a modelled estimate derived from surrounding terrain rather than a measurement on the water, so treat it as approximate.

Are there boat ramps on Heron Lake?

Heron Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Jack Creek. Public access is listed as yes.

Where this data comes from

4 measurements from 1 monitoring station, 2023. Retrieved from the EPA Water Quality Portal on 2026-08-02.

Collected and reported by

  • Minnesota Pollution Control Agency - Ambient Surface WaterMNPCA4 samples · 2023

Analytical methods

  • Field measurement/observation, generic method
  • Phosphorus by Colorimetry
  • 10200 H ~ Chlorophyll a-b-c Determination
  • 2120 B ~ Color in Water by Visual Comparison
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

Regulated discharger data from EPA ECHO (ICIS-NPDES)

Lake size & watershed from HydroLAKES (HydroSHEDS)

Lake details from Minnesota DNR LakeFinder

Named boat-access points from the USGS National Boat Ramps inventory