Skip to content
TapBuff
ZIP

Madison Lake

What EPA’s and Minnesota’s records show in this utility’s water: nitrate, arsenic and other regulated chemicals; lead and copper; and violations since 2016, with the certification that handles each result.

Serves
1,017 people
Connections
668
Water source
Groundwater
Based in
Madison Lake, MN
County
Blue Earth
Owner
Local government
The ZIP code it serves

56063

The short answer

1 result is above the health goal. The worst: Arsenic, above the health goal. No health-based violations on file since 2016.

What handles it

What was found

Copper: EPA’s file records a utility’s copper only when it exceeds the action level. The last here was 1.5 ppm, for the period ending Dec. 31, 2009. None since is on file, so it is not counted as a current finding.

Arsenic, total trihalomethanes (TTHM), haloacetic acids (HAA5), nitrate and uranium: Minnesota’s yearly summaries per water system, 2023 to 2025, with EPA’s 2012 to 2019 file for earlier years.

Fluoride and chromium (total): EPA’s compliance monitoring file, samples taken from Feb. 28, 2012 to Dec. 10, 2019. Newer results are in the utility’s annual water quality report.

Above the health goal1

Arsenic

Comes from the source

Above the health goal

4.4ppb

Highest yearly average, 2025

Averaged by year, the highest was 4.4 ppb, in 2025: below EPA’s legal limit of 10 ppb, but above its health goal of zero. That is the only year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 4.1 ppb, in 2014.

What handles it

  • NSF/ANSI 58 look for “Arsenic (Pentavalent)<=50 ppb Reduction”
  • NSF/ANSI 53 look for “Arsenic (Pentavalent)<=50 ppb Reduction”

Below EPA’s limits3

Total trihalomethanes (TTHM)

Forms or is added in treatment

Below EPA’s limits

61.4ppb

Highest yearly average, 2023 to 2025

2025 average: 50.2 ppb

Averaged by year, the highest was 61.4 ppb, in 2023, below EPA’s legal limit of 80 ppb. In 2025, the latest year on file, it averaged 50.2 ppb.

What handles it

  • NSF/ANSI 53 look for “Trihalomethanes (TTHM) Reduction”
  • NSF/ANSI 58 look for “Trihalomethanes (TTHM) Reduction”

Haloacetic acids (HAA5)

Forms or is added in treatment

Below EPA’s limits

38ppb

Highest yearly average, 2023 to 2025

2025 average: 15.1 ppb

Averaged by year, the highest was 38 ppb, in 2023, below EPA’s legal limit of 60 ppb. In 2025, the latest year on file, it averaged 15.1 ppb.

What handles it

No certification claim covers this compound yet.

Fluoride

Forms or is added in treatment

Below EPA’s limits

1.4ppm

Highest yearly average, 2012 to 2019

2019 average: 0.93 ppm

Averaged by year, the highest was 1.4 ppm, in 2013, below EPA’s legal limit of 4.0 ppm. Its highest single sample was 1.6 ppm. In 2019, the latest year on file, its three samples averaged 0.93 ppm.

What handles it

4 compounds tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.
  • Chromium (total)
  • Lead
  • Nitrate
  • Uranium

What handles it

A certification covers specific claims, not a whole standard. Look for these claims on the certifier’s listing, not the box. Wording varies a little: NSF writes “Lead Reduction,” WQA just “Lead.”

  • NSF/ANSI 53

    Claim: Arsenic (Pentavalent)<=50 ppb Reduction

    For: Arsenic

    Other certifiers’ wording: Arsenic (III) (50 ppb influent level)

  • NSF/ANSI 58

    Claim: Arsenic (Pentavalent)<=50 ppb Reduction

    For: Arsenic

    Other certifiers’ wording: Arsenic (Pentavalent)<=300 ppb Reduction; Arsenic (V) (300 ppb influent level)

At the tap, or for the whole house?

These come with the water itself, so a whole-house system certified for the same claims treats every tap and shower. A filter at the tap treats drinking water for much less. How whole-house systems compare.

Filters with those claims on a certifier’s listing

Disclosure: TapBuff earns a commission if you buy through some links on this page. It does not change which standard or filter we name. As an Amazon Associate, TapBuff earns from qualifying purchases. How TapBuff makes money

Compare five-year costs

The best reverse osmosis systems, ranked

Violations since 2016

No health-based violations on file with EPA since 2016. There are 3 monitoring or reporting violations: a sample missed, late or not reported.

What this report can’t tell you

  • Everything else. Arsenic, total trihalomethanes (TTHM), haloacetic acids (HAA5), nitrate and uranium results here are Minnesota’s own yearly summaries from 2023 on, with EPA’s national file for 2012 to 2019. Fluoride and chromium (total) come from EPA’s file alone, which ends in 2019. Madison Lake’s own annual report, which it must send you every year, has newer results for those and the contaminants this page does not show.

  • Your own plumbing. Lead results are the 90th percentile across homes the utility samples. Your home’s service line, solder and fixtures decide yours. A certified lab test is the only way to know.

  • What it means for your health. This page reports what the records show and EPA’s limits and goals; it is not medical advice. If you are worried about a health effect, talk to a doctor or your local health department.

  • Anything after the latest data. SDWIS data is from 2026 Q3; UCMR 5 didn’t sample this utility; Minnesota’s yearly summaries cover 2023 to 2025; EPA’s compliance samples are from Feb. 28, 2012 to Dec. 10, 2019.

Testing your own tap

Madison Lake’s results are for the water it sends out. What your own service line, solder and fixtures add shows up only in a test of your tap, by a lab Minnesota certifies.

The 3 labs Minnesota certifies closest to the area Madison Lake serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.

  • UC Laboratory

    Janesville, MN · about 10 miles

    Certified for bacteria, nitrate, metals

    (507) 234-5835

  • Minnesota Valley Testing Laboratories, Inc.

    New Ulm, MN · about 33 miles

    Certified for bacteria, nitrate, lead and copper, metals

    (507) 354-8517

  • RMB Environmental Laboratories, Inc. - Burnsville

    Burnsville, MN · about 47 miles

    Certified for bacteria, nitrate

    (952) 456-8470

All 24 certified labs for Minnesota

Sources

PWSID MN1070007. Rebuilt from EPA data on Oct. 18, 2026.

Also in Blue Earth County

All Minnesota utilities

What to do next