Skip to content
TapBuff
ZIP

Northfield San Dist 1

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
50 people
Connections
38
Water source
Groundwater
Based in
Hixton, WI
County
Jackson
Owner
Local government
Hardness
Moderately hard
The ZIP code it serves

54635

The short answer

1 result is above the health goal. The worst: Arsenic, above the health goal. 1 health-based violation since 2016.

What handles it

What was found

Arsenic, total trihalomethanes (TTHM), fluoride, nitrate, haloacetic acids (HAA5) and chromium (total): Wisconsin’s own results, samples taken from May 11, 2020 to Sept. 17, 2025, with EPA’s 2012 to 2019 file for earlier years.

Above the health goal1

Arsenic

Comes from the source

Above the health goal

0.87ppb

Highest yearly average, 2020 to 2023

2023: not found

Averaged by year, the highest was 0.87 ppb, in 2020: below EPA’s legal limit of 10 ppb, but above its health goal of zero. In 2023, the latest year on file, it wasn’t found in its one sample.

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 limits5

Total trihalomethanes (TTHM)

Forms or is added in treatment

Below EPA’s limits

10.3ppb

Highest yearly average, 2022 to 2025

2025, one sample: 5.6 ppb

Averaged by year, the highest was 10.3 ppb, in 2022, below EPA’s legal limit of 80 ppb. In 2025, the latest year on file, its one sample was 5.6 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 8.9 ppb, in 2019.

What handles it

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

Fluoride

Forms or is added in treatment

Below EPA’s limits

0.35ppm

Highest yearly average, 2020 to 2023

2023, one sample: 0.31 ppm

Averaged by year, the highest was 0.35 ppm, in 2020, below EPA’s legal limit of 4.0 ppm. In 2023, the latest year on file, its one sample was 0.31 ppm. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 0.35 ppm, in 2014.

What handles it

Nitrate

Comes from the source

Below EPA’s limits

0.72ppm

Highest sample; found in 7 of 7

2023 average: 0.71 ppm

The highest sample, in 2023, was 0.72 ppm, below EPA’s legal limit of 10 ppm. That was also the latest year on file, and its two samples averaged 0.71 ppm. Earlier, from 2012 to 2019, EPA’s file shows a highest sample of 7.0 ppm, in 2019.

What handles it

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

Haloacetic acids (HAA5)

Forms or is added in treatment

Below EPA’s limits

2.6ppb

Highest yearly average, 2022 to 2025

Averaged by year, the highest was 2.6 ppb, in 2025, below EPA’s legal limit of 60 ppb. That was also the latest year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 18.5 ppb, in 2016.

What handles it

No certification claim covers this compound yet.

Chromium (total)

Comes from the source

Below EPA’s limits

0.68ppb

Highest yearly average, 2020 to 2023

2023: not found

Averaged by year, the highest was 0.68 ppb, in 2020, below EPA’s legal limit of 100 ppb. In 2023, the latest year on file, it wasn’t found in its one sample.

What handles it

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

The best reverse osmosis systems, ranked

Hardness

Moderately hard, 63 mg/L (3.7 grains per gallon), at its one sampling point, in 2017.

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 3.7 grains per gallon, salt includedSoftener or salt-free conditioner?Wisconsin water hardness, utility by utility

Violations since 2016

Contaminant or ruleTypePeriodMeasuredStatus
Stage 1 Disinfectants and Disinfection Byproducts RuleTreatment was not run by a certified operator as required.EPA: Treatment Technique No Certif. OperatorMay 2, 2022—Resolved
Health-based violations only. Resolved and archived mean the utility returned to compliance or the state closed the record. 3 monitoring or reporting violations not shown.

What this report can’t tell you

  • Everything else. Arsenic, total trihalomethanes (TTHM), fluoride, nitrate, haloacetic acids (HAA5) and chromium (total) results here are Wisconsin’s own from 2020 on, with EPA’s national file for 2012 to 2019. Northfield San Dist 1’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; Wisconsin’s results run from May 11, 2020 to Sept. 17, 2025.

Testing your own tap

Northfield San Dist 1’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 Northfield San Dist 1 serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.

  • Jackson County Public Health Water Lab

    Black River Falls, WI · about 15 miles

    Certified for bacteria, nitrate

    (715) 284-4301

  • Clark County Health Department

    Neillsville, WI · about 23 miles

    Certified for bacteria

    (715) 743-5105

  • Monroe County Health Department

    Sparta, WI · about 31 miles

    Certified for bacteria

    (608) 269-8666

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 WI6270004. Rebuilt from EPA data on Oct. 18, 2026.

Towns it serves

Also in Jackson County

All Wisconsin utilities

What to do next