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Mazomanie MHP

What EPA’s and Wisconsin’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
85 people
Connections
40
Water source
Groundwater
Based in
Mazomanie, WI
County
Dane
Owner
Private
Hardness
Very hard
The ZIP code it serves

53560

The short answer

2 results are above the health goal. The worst: Lead, above the health goal. No health-based violations on file since 2016.

What handles it

What was found

Lead and copper: EPA SDWIS monitoring periods ending 2000 to 2021.

Total trihalomethanes (TTHM), haloacetic acids (HAA5) and nitrate: Wisconsin’s own results, samples taken from May 11, 2020 to Aug. 26, 2025, with EPA’s 2012 to 2019 file for earlier years.

Uranium, arsenic, chromium (total) and fluoride: EPA’s compliance monitoring file, samples taken from Aug. 30, 2012 to June 19, 2018. Newer results are in the utility’s annual water quality report.

Above the health goal2

Lead

Comes from pipes, often your own

Above the health goal

0.18ppb

90th percentile, 2021

In the latest period, 9 in 10 homes sampled were at or below 0.18 ppb, below EPA’s action level of 15 ppb. The action level drops to 10 ppb on Nov. 1, 2027. EPA’s health goal for lead is zero.

What handles it

Uranium

Comes from the source

Above the health goal

0.03ppb

Highest yearly average, 2012

Averaged by year, the highest was 0.03 ppb, in 2012: below EPA’s legal limit of 30 ppb, but above its health goal of zero. That is the only year on file.

What handles it

Below EPA’s limits3

Total trihalomethanes (TTHM)

Forms or is added in treatment

Below EPA’s limits

4.4ppb

Highest yearly average, 2022 to 2025

Averaged by year, the highest was 4.4 ppb, in 2025, below EPA’s legal limit of 80 ppb. That was also the latest year on file.

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

2.0ppb

Highest yearly average, 2022 to 2025

2025, one sample: 0.89 ppb

Averaged by year, the highest was 2.0 ppb, in 2022, below EPA’s legal limit of 60 ppb. In 2025, the latest year on file, its one sample was 0.89 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 2.1 ppb, in 2016.

What handles it

No certification claim covers this compound yet.

Nitrate

Comes from the source

Below EPA’s limits

0.33ppm

Highest sample; found in 2 of 2

2021, one sample: 0.049 ppm

The highest sample, in 2020, was 0.33 ppm, below EPA’s legal limit of 10 ppm. In 2021, the latest year on file, its one sample was 0.049 ppm. Earlier, from 2012 to 2019, EPA’s file shows a highest sample of 0.12 ppm, in 2017.

What handles it

  • NSF/ANSI 58 look for “Nitrate/Nitrite Reduction”
  • NSF/ANSI 53 look for “Nitrate/Nitrite (30 ppm challenge)”
3 compounds tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.
  • Arsenic
  • Chromium (total)
  • Fluoride

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.”

At the tap, or for the whole house?

Lead and copper usually come from pipes and fixtures inside or near your home. A whole-house system sits where water enters, so it cannot catch what your own plumbing adds after it. For those, the filter that counts is the one at the tap. 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 water filters for lead, ranked

Hardness

Very hard, 290 mg/L (17 grains per gallon), at its one sampling point, in 2018.

Hardness is calcium and magnesium. EPA sets no limit for it: it shows up as scale on fixtures and in water heaters, and as soap that won’t lather. USGS calls water above 60 mg/L moderately hard, above 120 hard and above 180 very hard.

Softeners compared at 17 grains per gallon, salt includedSoftener or salt-free conditioner?Wisconsin water hardness, utility by utility

Violations since 2016

No health-based violations on file with EPA since 2016. There are 7 monitoring or reporting violations: a sample missed, late or not reported.

What this report can’t tell you

  • Everything else. Total trihalomethanes (TTHM), haloacetic acids (HAA5) and nitrate results here are Wisconsin’s own from 2020 on, with EPA’s national file for 2012 to 2019. Uranium, arsenic, chromium (total) and fluoride come from EPA’s file alone, which ends in 2019. Mazomanie MHP’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; Wisconsin’s results run from May 11, 2020 to Aug. 26, 2025; EPA’s compliance samples are from Aug. 30, 2012 to June 19, 2018.

Testing your own tap

Mazomanie MHP’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 Wisconsin certifies.

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

  • Water Quality Investigations

    Mt Horeb, WI · about 16 miles

    Certified for bacteria

    (888) 499-2507

  • Wisconsin State Laboratory of Hygiene

    Madison, WI · about 19 miles

    Certified for bacteria, nitrate, lead and copper, metals, minerals and other inorganics, organic chemicals, disinfection byproducts, PFAS, radioactivity

    (608) 224-6260

  • Public Health Madison & Dane County

    Madison, WI · about 20 miles

    Certified for bacteria

    (608) 243-0357

Wisconsin State Laboratory of Hygiene: Well water test kits ordered by phone and shipped free; you pay to mail the sample back, and the lab bills you after testing. Tests run from bacteria alone to a homeowner package covering bacteria, nitrate, fluoride, metals, hardness, volatile organic compounds and atrazine. Bacteria is $35, nitrate $35, lead $38, and the homeowner package $450, as of July 1, 2026. Public Environmental and Water Testing Prices, Wisconsin State Laboratory of Hygiene.

All 156 certified labs for Wisconsin

Sources

PWSID WI1130240. Rebuilt from EPA data on Oct. 18, 2026.

Towns it serves

Also in Dane County

All Wisconsin utilities

What to do next