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LakeQuality

Henry Lake

NR
Not yet rated
2 ft clear · Eutrophic
Limited DataEutrophic

Henry Lake in Le Sueur County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 2 ft visibility.

Clarity
2 ft
Mean depth
~9 ft est.
Trend
Improving
Public access
Yes

Next lake in Le Sueur County

FJefferson Lake2 ft clear · Le Sueur CountyView →
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Why Henry 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 Henry 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.

Henry Lake is a lake in Le Sueur County, Minnesota with an estimated average depth of about 9 feet. Overall water quality is improving over recent sampling years. Limited fish-species data available. Public access is available with 2 public boat landings.

Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2025-09-30. 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 Mankato

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Water quality measurements for Henry Lake

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

Very murky, less than 2 ft of visibility. Trophic State Index: 67.

MetricValueGrade
Water Clarity (Secchi Depth)2 ftNot graded
PhosphorusNo recent samples
Chlorophyll-a (Algae)No recent samples
Trophic State Index (TSI)67Eutrophic

High nutrients, frequent algae, reduced clarity

Where to stay near Henry Lake

Compare lakeside cabins, hotels, and vacation rentals near Henry Lake in Le Sueur 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 Henry 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 →

Lake Details

CharacteristicValue
Average Depth~9 ft est.
Public AccessYes

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

Lake Size & Watershed

Watershed (drainage) area
12 sq mi
Surface area
341 acres
Mean depth (modeled estimate)
~9 ft est.
Shoreline
3 mi
Elevation
1,010 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

2
Boat Landings
Yes
Public Access
  • Jefferson Lake (West)Public
  • Henry LakePublic

Fishing Henry Lake

DNR Reports & Resources

Minnesota DNR LakeFinder publishes lake survey, fish stocking, water access, and aquatic plant data for Henry Lake. 2 reports on file.

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

Based on 6 years of monitoring data (2020-2025).

MetricTrendChange/YearYears
Water Clarity Improving+0.021 m/yr6
See year-by-year chart →

EPA Impairment Status

Henry 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 MN40-0104-00 · Official waterbody report

Graded lakes near Henry Lake

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

Nearby Lakes in Le Sueur County

Frequently asked questions about Henry Lake

What is the water quality grade for Henry Lake?

Henry Lake in Le Sueur County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Water clarity: 2 ft visibility.

Is Henry Lake safe to swim in?

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

How deep is Henry Lake?

No published bathymetric survey covers Henry Lake, so its depth has not been measured. The HydroLAKES global model estimates an average depth of about 9 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 Henry Lake?

Henry Lake has 2 documented boat landings in the USGS National Boat Ramps inventory. Named access points include Jefferson Lake (West), Henry Lake. Public access is listed as yes.

Where this data comes from

13 measurements from 1 monitoring station, 2024–2025. Retrieved from the EPA Water Quality Portal on 2026-08-02.

Collected and reported by

  • Minnesota Pollution Control Agency - Ambient Surface WaterMNPCA13 samples · 2024–2025

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

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