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Saint Leo

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
97 people
Connections
54
Water source
Groundwater bought from another system
Based in
St. Leo, MN
County
Yellow Medicine
Owner
Local government
The ZIP code it serves

56264

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

Arsenic, nitrate, total trihalomethanes (TTHM) and haloacetic acids (HAA5): Minnesota’s yearly summaries per water system, 2023 to 2025.

Above the health goal1

Arsenic

Comes from the source

Above the health goal

1.4ppb

Highest yearly average, 2023 to 2025

Averaged by year, the highest was 1.4 ppb, in 2025: below EPA’s legal limit of 10 ppb, but above its health goal of zero. That was also the latest year on file.

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

Nitrate

Comes from the source

Below EPA’s limits

6.2ppm

Highest yearly average, 2023 to 2025

2025 average: 5.8 ppm

Averaged by year, the highest was 6.2 ppm, in 2023, below EPA’s legal limit of 10 ppm. In 2025, the latest year on file, it averaged 5.8 ppm.

What handles it

  • NSF/ANSI 58 look for “Nitrate/Nitrite Reduction”
  • NSF/ANSI 53 look for “Nitrate/Nitrite (30 ppm challenge)”

Total trihalomethanes (TTHM)

Forms or is added in treatment

Below EPA’s limits

12.6ppb

Highest yearly average, 2023 to 2025

2025 average: 12.5 ppb

Averaged by year, the highest was 12.6 ppb, in 2024, below EPA’s legal limit of 80 ppb. In 2025, the latest year on file, it averaged 12.5 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

4.9ppb

Highest yearly average, 2023 to 2025

Averaged by year, the highest was 4.9 ppb, in 2025, below EPA’s legal limit of 60 ppb. That was also the latest year on file.

What handles it

No certification claim covers this compound yet.

One compound tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.
  • Lead

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

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Violations since 2016

No health-based violations on file with EPA since 2016.

What this report can’t tell you

  • Everything else. Arsenic, nitrate, total trihalomethanes (TTHM) and haloacetic acids (HAA5) results here are Minnesota’s own yearly summaries from 2023 on, with EPA’s national file for 2012 to 2019. Saint Leo’s own annual report, which it must send you every year, has 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.

Testing your own tap

Saint Leo’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 lab Minnesota certifies closest to the area Saint Leo serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.

  • Southwest Health and Human Services

    Marshall, MN · about 14 miles

    Certified for bacteria, nitrate

    (507) 537-6713

All 24 certified labs for Minnesota

Sources

PWSID MN1870007. Rebuilt from EPA data on Oct. 18, 2026.

Also in Yellow Medicine County

All Minnesota utilities

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