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Monona Municipal Water Dept

What EPA’s and Iowa’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
1,471 people
Connections
718
Water source
Groundwater
Based in
Monona, IA
County
Clayton
Owner
Local government
The ZIP code it serves

52159

The short answer

1 result is 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 2002 to 2023.

Haloacetic acids (HAA5), total trihalomethanes (TTHM), fluoride, arsenic, chromium (total) and nitrate: Iowa’s own results, samples taken from April 7, 2020 to Aug. 11, 2026, with EPA’s 2012 to 2019 file for earlier years.

Uranium: EPA’s compliance monitoring file, samples taken from April 23, 2018 to April 23, 2018. Newer results are in the utility’s annual water quality report.

Above the health goal1

Lead

Comes from pipes, often your own

Above the health goal

3.5ppb

90th percentile, 2021 to 2023

In the latest period, 9 in 10 homes sampled were at or below 3.5 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 limits3

Haloacetic acids (HAA5)

Forms or is added in treatment

Below EPA’s limits

11.7ppb

Highest yearly average, 2020 to 2026

Averaged by year, the highest was 11.7 ppb, in 2026, 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 9.0 ppb, in 2016.

What handles it

No certification claim covers this compound yet.

Total trihalomethanes (TTHM)

Forms or is added in treatment

Below EPA’s limits

12.2ppb

Highest yearly average, 2020 to 2026

2026, one sample: 7.7 ppb

Averaged by year, the highest was 12.2 ppb, in 2022, below EPA’s legal limit of 80 ppb. In 2026, the latest year on file, its one sample was 7.7 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 15.6 ppb, in 2016.

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

0.55ppm

Highest yearly average, 2021

Averaged by year, the highest was 0.55 ppm, in 2021, below EPA’s legal limit of 4.0 ppm. Its highest single sample was 0.6 ppm. That is the only year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 0.8 ppm, in 2012.

What handles it

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

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

Violations since 2016

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

What this report can’t tell you

  • Everything else. Haloacetic acids (HAA5), total trihalomethanes (TTHM), fluoride, arsenic, chromium (total) and nitrate results here are Iowa’s own from 2020 on, with EPA’s national file for 2012 to 2019. Uranium comes from EPA’s file alone, which ends in 2019. Monona Municipal Water Dept’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; Iowa’s results run from April 7, 2020 to Aug. 11, 2026; EPA’s compliance samples are from April 23, 2018 to April 23, 2018.

Testing your own tap

Monona Municipal Water Dept’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 Iowa certifies.

The 3 labs Iowa certifies closest to the area Monona Municipal Water Dept serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.

  • Dubuque County Health Department

    Dubuque, IA · about 49 miles

    Certified for bacteria

    (563) 557-7396

  • Davy Laboratories

    La Crosse, WI · about 52 miles

    Certified for bacteria

    (608) 782-3130

  • Microbac Laboratories - Waterloo

    Waterloo, IA · about 67 miles

    Certified for bacteria, nitrate

    (319) 235-4440

State Hygienic Laboratory at the University of Iowa: Through the Grants-to-Counties program, private well owners in participating counties can have their water tested for total coliform bacteria and nitrate. Start with the county sanitarian at your county health department. No cost in a participating county. The Grants-to-Counties Program, State Hygienic Lab at the University of Iowa.

All 36 certified labs for Iowa

Sources

PWSID IA2264095. Rebuilt from EPA data on Oct. 18, 2026.

Also in Clayton County

All Iowa utilities

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