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Iowa PFAS Contamination Map: Drinking Water Detections by Utility

PFAS in Iowa drinking water

32 drinking-water utilities in Iowa reported PFAS detections at or above the EPA minimum reporting level under UCMR 5 (the federal monitoring round that ran 2023–2025). Of those, 6 exceeded the final EPA Maximum Contaminant Level for PFOA or PFOS (4 parts per trillion), serving roughly 331,012 people.

By the numbers

  • 32 Iowa water utilities with at least one PFAS compound detected
  • 579,872 people served by those utilities
  • 6 utilities above the final 4 ppt MCL for PFOA or PFOS
  • 8 federal and Department of Defense sites with reported PFAS in groundwater

The interactive map below plots every reporting Iowa utility, colour-coded by whether their worst reading exceeds the federal MCL, sits below it but at or above the reporting threshold, or falls below the reporting threshold. Use the search box to find a specific utility, ZIP code or address.

Top Iowa water utilities by PFAS impact

The 15 Iowa public water systems with the most significant PFAS detections under UCMR 5, ranked by how far each system’s worst MCL-exceeding compound runs over the federal limit:

#UtilityPopulation servedHeadline ng/LCompoundvs MCL
1Waverly Water Department10,3947.2PFOA1.8× final MCL
2Muscatine Power & Water23,7977.2PFOA1.8× final MCL
3Sioux City Water Supply85,7975.4PFOA1.4× final MCL
4Dubuque Water Works59,6675.1PFOA1.3× final MCL
5Osage Municipal Water Supply3,6374.2PFOS1.1× final MCL
6Iowa-American Wtr Co-Davenport147,7204.1PFOA1.0× final MCL
7Iowa-American Wtr Co-Clinton District24,769647.9PFBADetected only
8Rathbun Reg Wtr Assn (Burlington)9,00032.0PFBADetected only
9West Burlington Muni. Water Supply3,72824.0PFBADetected only
10Burlington Municipal Waterworks26,01512.0PFBADetected only
11Chariton Municipal Water Works4,56812.0PFBADetected only
12Rathbun Reg Water Assn (Ft Madison)10,44011.0PFBADetected only
13Waterloo Water Works69,1939.8PFHxSDetected only
14Osceola Water Works5,4159.3PFBADetected only
15Garden Grove Water Supply1799.0PFBADetected only
Source: EPA PFAS Analytic Tools (UCMR 5, 2023–2025). For utilities exceeding an MCL the headline reading is the worst MCL-exceeding compound at that system; for detection-only utilities it is the highest reading on any compound.

Use the interactive map above to find every utility (not just the top 15) and to search by ZIP code or address.

The biggest Iowa systems above the PFOA/PFOS MCL

Ranked by population served, the largest Iowa water utilities reporting at least one PFAS reading above EPA’s final MCL:

#UtilityPopulation servedWorst compoundReadingvs MCL
1Iowa-American Wtr Co-Davenport147,720PFOA4.1 ng/L1.0× MCL
2Sioux City Water Supply85,797PFOA5.4 ng/L1.4× MCL
3Dubuque Water Works59,667PFOA5.1 ng/L1.3× MCL
4Muscatine Power & Water23,797PFOA7.2 ng/L1.8× MCL
5Waverly Water Department10,394PFOA7.2 ng/L1.8× MCL
Source: EPA UCMR 5. Public water systems serving 10,000 or more residents only.

PFAS compounds detected in Iowa

UCMR 5 required utilities to test for 29 different PFAS compounds. The table below shows how many Iowa utilities had at least one above-reporting-level result for each compound, sorted by frequency:

CompoundIowa utilitiesShare of detecting utilitiesEPA MCL
PFBA2475%None
PFBS1238%None
PFPeA928%None
PFHxS722%10 ppt (April 2024, under reconsideration)
PFOA619%4 ppt (final)
PFHxA619%None
PFOS39%4 ppt (final)
PFHpA39%None
PFPeS13%None
PFMBA13%None
PFMPA13%None
Source: EPA UCMR 5 (2023–2025). Only six PFAS compounds are subject to enforceable EPA Maximum Contaminant Levels in drinking water; the others are unregulated at the federal level.

Where Iowa’s PFAS contamination is coming from

EPA’s PFAS Analytic Tools also catalogue the suspected industrial, federal and accidental sources of PFAS in each state. Iowa has 8 federal facilities (mostly U.S. military installations and federal airports) reporting PFAS in groundwater, 2 EPA Superfund sites flagged for PFAS, and 3 recorded PFAS-related spills (2 of which reached surface water).

Federal and DoD sites with the highest PFAS in groundwater

The U.S. Department of Defense has reported PFAS contamination at hundreds of installations nationwide, largely tied to decades of fire-training exercises with PFAS-based firefighting foams (AFFF). These readings are taken from monitoring wells at the source site, not from drinking-water taps, but plumes from these sites are a known route into nearby public and private water supplies. Readings are in parts per trillion (ppt) of PFOS and PFOA respectively:

SiteAgencyMax PFOS (groundwater)Max PFOA (groundwater)
Des MoinesAir Force13,000 ppt1,900 ppt
Sioux Gateway (Sioux City) SIOUX CTY APT ANG (EESOH-MIS name)Air Force7,800 ppt850 ppt
Davenport AASFArmy4,250 ppt375 ppt
Boone AASFArmy1,070 ppt240 ppt
Camp Dodge Johnston Training SiteArmy347 ppt6 ppt
Source: EPA PFAS Analytic Tools, federal-sites layer. Readings are PFOS and PFOA maxima measured in monitoring wells at each installation; they do not represent finished drinking water.

Superfund sites flagged for PFAS in Iowa

EPA’s Superfund program has identified the following Iowa sites with confirmed PFAS detections:

  • Iowa Army Ammunition Plant, Middletown, Des Moines County. NPL status: Final. EPA site report
  • Lawrence Todtz Farm, Camanche, Clinton County. NPL status: Final. EPA site report

Recent PFAS-related spills in Iowa

  • 2024: 1 pints of aqueous film-forming foam (AFFF) released in Dubuque (Dubuque County) by Uscgc Wyaconda. Reached water.

What “exceeds the MCL” means here

In April 2024 the EPA finalised the first-ever federal Maximum Contaminant Levels (MCLs) for six PFAS compounds in drinking water. The two most consequential are PFOA and PFOS, both set at 4.0 nanograms per litre (ng/L) — equivalent to 4 parts per trillion. Every red marker on the map above represents a Iowa water system whose most-recent UCMR 5 result for PFOA or PFOS sat above 4 ng/L.

EPA also issued individual MCLs of 10 ng/L for PFHxS, PFNA and HFPO-DA (GenX) and a Hazard-Index MCL covering mixtures. In May 2025 the agency confirmed the PFOA and PFOS limits would stay in place (with the compliance deadline extended to 2031), and announced its intent to rescind the four other limits. We continue to flag exceedances of the published April 2024 MCL for those compounds and label them as “under EPA reconsideration” so the rule status is honest and current.

Yellow markers mean PFAS were detected at or above EPA’s reporting threshold (the minimum reporting level) but no individual compound exceeded an MCL. Detection at any level is not necessarily a regulatory violation, but it is a signal that PFAS treatment may be needed before the 2031 compliance deadline.

Methodology and data sources

  • Drinking-water detections: EPA PFAS Analytic Tools, UCMR 5 layer. Filtered to Iowa samples at or above the minimum reporting level. We aggregate the raw 2023–2025 sample records to one entry per public water system, taking the most-recent reading per compound.
  • Superfund sites: EPA PFAS Analytic Tools, Superfund-with-PFAS layer. Includes National Priorities List sites and Superfund Alternative Approach sites where PFAS has been detected.
  • Federal and DoD sites: EPA PFAS Analytic Tools, federal-sites layer. PFOA and PFOS values are maximum readings from groundwater monitoring wells at each installation, not finished drinking water.
  • Spills: EPA PFAS Analytic Tools, spills layer. Covers reported releases involving PFAS-containing materials.

UCMR 5 only required community water systems serving 3,300 or more people, plus a representative sample of smaller systems, to test for PFAS. Private wells, very small public systems, and bottled water are not in this dataset. Absence of a dot on the map does not mean absence of PFAS.

What you can do

  • Check whether your utility appears in the table above or on the map. If it does, your utility is required to come into compliance with the federal PFOA/PFOS MCL by 2031 — usually via granular activated carbon, ion-exchange resin or reverse osmosis treatment.
  • If you are on a private well in or near a flagged area, consider independent PFAS testing through a state-certified laboratory.
  • Look up your most recent Consumer Confidence Report (CCR), which utilities are required to publish annually. PFAS results from UCMR 5 must now appear there.
  • If you want point-of-use protection, only filters certified to NSF/ANSI 53 or NSF/ANSI 58 for PFOA and PFOS reduction will reliably remove PFAS.

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About the Author
I'm Daniel O'Donohue, the voice and creator behind The MapScaping Podcast ( A podcast for the geospatial community ). With a professional background as a geospatial specialist, I've spent years harnessing the power of spatial to unravel the complexities of our world, one layer at a time.