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Cornish Town Water System

What EPA’s and Utah’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
275 people
Connections
119
Water source
Groundwater influenced by surface water
Based in
Cornish, UT
County
Cache
Owner
Local government
Hardness
Very hard
The ZIP code it serves

84308

The short answer

1 result is above EPA’s legal limit, and 2 more are above the health goal. The worst: Nitrate, above the legal limit. 5 health-based violations since 2016.

What handles it

What was found

Lead and copper: EPA SDWIS monitoring periods ending 1997 to 2025.

Nitrate, arsenic, fluoride and chromium (total): Utah’s own results, samples taken from Aug. 24, 2020 to Sept. 29, 2026, with EPA’s 2012 to 2019 file for earlier years.

Total trihalomethanes (TTHM) and haloacetic acids (HAA5): EPA’s compliance monitoring file, samples taken from July 30, 2013 to Aug. 31, 2017. Newer results are in the utility’s annual water quality report.

Above the legal limit1

Nitrate

Comes from the source

Above the legal limit

15.9ppm

Highest sample; found in 76 of 81

2026 average: 2.9 ppm

From 2021 to 2026, eight samples were above EPA’s legal limit of 10 ppm, the highest 15.9 ppm in 2023. The next sample at the same point, within 30 days, kept the average above the limit for one; seven have no follow-up sample on file within 30 days. In 2026, the latest year on file, its 10 samples averaged 2.9 ppm. EPA recorded a violation for nitrate at this utility in 2023. Earlier, from 2012 to 2019, EPA’s file shows a highest sample of 4.8 ppm, in 2014.

What handles it

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

Above the health goal2

Arsenic

Comes from the source

Above the health goal

5.2ppb

Highest yearly average, 2023 to 2025

Averaged by year, the highest was 5.2 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. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 2.5 ppb, in 2013.

What handles it

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

Lead

Comes from pipes, often your own

Above the health goal

1.6ppb

90th percentile, 2023 to 2025

In the latest period, 9 in 10 homes sampled were at or below 1.6 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

Below EPA’s limits2

Fluoride

Forms or is added in treatment

Below EPA’s limits

2.4ppm

Highest yearly average, 2023 to 2025

Averaged by year, the highest was 2.4 ppm, in 2025, below EPA’s legal limit of 4.0 ppm. That was also the latest year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 1.8 ppm, in 2019.

What handles it

Total trihalomethanes (TTHM)

Forms or is added in treatment

Below EPA’s limits

1.7ppb

Highest yearly average, 2013 to 2017

Averaged by year, the highest was 1.7 ppb, in 2017, 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”
2 compounds tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.
  • Chromium (total)
  • Haloacetic acids (HAA5)

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

    Claims: Nitrate/Nitrite (30 ppm challenge), Arsenic (Pentavalent)<=50 ppb Reduction, Lead Reduction

    For: Nitrate, Arsenic, Lead

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

  • NSF/ANSI 58

    Claims: Nitrate/Nitrite Reduction, Arsenic (Pentavalent)<=50 ppb Reduction, Lead Reduction

    For: Nitrate, Arsenic, Lead

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

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 reverse osmosis systems, ranked

The best water filters for lead, ranked

Hardness

Very hard, 313 mg/L (18.3 grains per gallon), at its one sampling point, 2019 to 2025.

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 18.3 grains per gallon, salt includedSoftener or salt-free conditioner?Utah water hardness, utility by utility

Violations since 2016

Contaminant or ruleTypePeriodMeasuredStatus
Revised Total Coliform RuleE. coli was confirmed in the water system.EPA: Maximum Contaminant Level Violation, E. coli (RTCR)Jan. 1, 2025 to Jan. 31, 2025—Resolved
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleJune 1, 2023 to June 30, 202313.5 MG/LResolved
Groundwater RuleA significant problem found in a state inspection was not fixed on time.EPA: Failure To Address DeficiencyNov. 11, 2017—Resolved
Groundwater RuleA significant problem found in a state inspection was not fixed on time.EPA: Failure To Address DeficiencyNov. 11, 2017—Resolved
Groundwater RuleA significant problem found in a state inspection was not fixed on time.EPA: Failure To Address DeficiencyNov. 11, 2017—Resolved
Health-based violations only. Resolved and archived mean the utility returned to compliance or the state closed the record. 65 monitoring or reporting violations not shown.

What this report can’t tell you

  • Everything else. Nitrate, arsenic, fluoride and chromium (total) results here are Utah’s own from 2020 on, with EPA’s national file for 2012 to 2019. Total trihalomethanes (TTHM) and haloacetic acids (HAA5) come from EPA’s file alone, which ends in 2019. Cornish Town Water System’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; Utah’s results run from Aug. 24, 2020 to Sept. 29, 2026; EPA’s compliance samples are from July 30, 2013 to Aug. 31, 2017.

Testing your own tap

Cornish Town Water System’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 Utah certifies.

The 3 labs Utah certifies closest to the area Cornish Town Water System serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.

  • Bear River District Health Department Water Laboratory

    Logan, UT · about 18 miles

    Certified for bacteria, nitrate

    (435) 792-6578

  • Brigham City Laboratory

    Brigham City, UT · about 31 miles

    Certified for bacteria, minerals and other inorganics

    (435) 226-1443

  • Northrup Grumman Space Systems Environmental Laboratory

    Corinne, UT · about 39 miles

    Certified for nitrate, lead and copper, metals, minerals and other inorganics

    (801) 863-8117

All 60 certified labs for Utah

Sources

PWSID UTAH03005. Rebuilt from EPA data on Oct. 18, 2026.

Also in Cache County

All Utah utilities

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