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North America PFAS map: industrial groundwater, soil, and drinking water results
Contaminated properties, monitoring stations, and drinking water results across the United States and Canada, on one map. Open any pin to see the federal record behind it.
Choose the question you are asking
Counts.
Properties where contamination sits in soil or groundwater and a government body carries a cleanup obligation. US DoD installations, US Superfund sites with PFAS detected, Canadian federal sites with PFAS recorded, and the wider Canadian federal inventory with an open obligation.
Excludes.
Private, provincial, state, territorial and municipal registers, drinking water sample results, and any property that has never been assessed. An absent pin is not evidence of clean ground.
Read one pin as.
A pin marks a place with work attached. It carries no concentration, so pin size and colour never imply severity.
Three views, three different grains, and the totals are never combined. A property is a place where contamination sits in soil or groundwater and someone carries the cleanup. A station is a place where a sample was taken. A water system is a place where treated water was tested at the tap. One property can sit upstream of many stations and many water systems, and many water systems have no identified source property at all. A station measurement tells you PFAS was looked for in the environment. A site record tells you a government body has accepted an obligation on that ground. Each layer states its own source, what it counts, and where it stops.
352 DoD installations, counted separately: 475 Superfund PFAS sites, counted separately: 98 Canadian PFAS sites, counted separately: 3,919 Canadian federal sites, all contaminants
Filter control: Canadian pins only
This control filters the Canadian federal register by affected medium. It does not change what the map covers. The map always shows both the United States and Canada. The Canadian inventory records every medium found at a site, so one site can appear under groundwater, soil and sediment at the same time. The site count on the map stays at 97. United States DoD and Superfund pins are counted separately and are never added to the Canadian total.
Clusters open into individual records as you zoom in. Every pin links back to its source entry.
2
3
4
4
4
5
10
17
18
41
45
125
187
451
Leaflet | Tiles © Esri — Esri, HERE, Garmin, © OpenStreetMap contributors
Pin locations are approximate and based on the best available federal coordinates. A detection in a jurisdiction is confirmed; the exact facility location should be verified against the source record.
Download the data behind this view
What each layer on this view is built from
United States, Department of Defense installations
352 installations
Published by.
US Department of Defense PFAS installation list
What one record is.
One record per installation
Where this layer stops.
The pin marks the installation boundary, not a sample point or a plume. Assessment status varies from initial screening to active cleanup. Installations with no published PFAS record do not appear, which is not evidence of a clean site.
United States, Superfund sites with PFAS detected
475 sites
Published by.
EPA Superfund Enterprise Management System, via EPA PFAS Analytic Tools
What one record is.
One record per Superfund site
Where this layer stops.
PFAS was detected in site media such as soil or groundwater. Coordinates are the site record location and are approximate. Sites where PFAS has not been analysed are absent from this layer.
Canada, federal sites with PFAS recorded
97 sites
Published by.
Treasury Board of Canada Secretariat, Federal Contaminated Sites Inventory
What one record is.
One record per federal site
Where this layer stops.
PFAS is recorded as a contaminant of concern by the custodian department. The inventory reports sites, not concentrations. Provincial, territorial, municipal and private sites are outside this inventory.
Canada, all federal contaminated sites, every contaminant
3,919 sites drawn of 24,426 in the inventory
Published by.
Treasury Board of Canada Secretariat, Federal Contaminated Sites Inventory
What one record is.
One record per federal site
Where this layer stops.
Every contaminant class, not PFAS alone. Only sites with an open federal obligation are drawn, plus every PFAS tagged site. This layer overlaps the PFAS tagged Canadian layer by design, so the two counts are shown separately and are never added together.
What the pin colours mean
United States, filled brown pin, DoD PFAS installations
A Department of Defense installation where PFAS assessment or remediation is proceeding or complete. 352 installations are plotted. These are source-contamination sites, not drinking water systems. Nearby UCMR 5 water system results are summarised in the popup.
United States, hollow charcoal square, Superfund sites with PFAS detected
A Superfund site in EPA's SEMS database where PFAS has been detected in site media, most often soil and groundwater. 475 sites are plotted, 142 of them federal facilities and 425 listed final on the National Priorities List. These are cleanup properties with a remediation programme attached, so they carry no concentration colour.
Canada, hollow rings, federal site register
A federal site with PFAS recorded as a contaminant of concern. 97 sites, covering groundwater, soil, sediment and surface water rather than drinking water. These are site records, so they carry no concentration colour. Federal priority class and the affected media are in the popup.
Canada, small grey dots, all federal contaminated sites
A federal site with an open obligation for any contaminant class, PFAS included where it is recorded. 3,919 sites are drawn. This layer overlaps the PFAS tagged Canadian layer above, so read the two counts separately and never add them.
Read the layers on this map differently
United States, DoD installations. The Department of Defense PFAS installation list marks military properties where assessment or remediation is proceeding or complete. These are source-contamination sites, not drinking water systems. Nearby UCMR 5 results are summarised in the popup.
United States, Superfund sites. EPA's PFAS Analytic Tools flag Superfund sites where PFAS has been detected in site media, most often soil and groundwater. Every pin has a federal cleanup programme and a responsible party behind it, which makes this the closest thing the United States publishes to a national contaminated land layer for PFAS.
Canada, contaminated land. The Federal Contaminated Sites Inventory records the site itself and every medium affected, most often groundwater and soil. It reports no concentrations, so a pin marks a property under federal management.
Canada, the wider federal inventory. Every contaminant class where the obligation is still open, PFAS included. It is a picture of federal liability on land, so it overlaps the PFAS tagged layer and the two counts stay separate.
These datasets answer different questions and the counts should never be added together. A station measurement is evidence that PFAS was looked for at a point in the environment. A site record is evidence that a government body has accepted an obligation on a piece of ground. Canada publishes no national drinking water sampling programme equivalent to UCMR 5, and the United States publishes no single soil and groundwater PFAS inventory equivalent to the FCSI. The DoD and Superfund layers together are the closest available US view of land that has to be remediated rather than water that has to be treated. State cleanup registers will add further industrial sites.
US public water systems with a PFAS detection
3,539
US systems above at least one 2024 EPA drinking water limit
1,717
US systems above the EPA mixture Hazard Index
230
US DoD installations with PFAS activity
352
US Superfund sites with PFAS detected in site media
475
Canadian federal sites with PFAS in soil or groundwater
97
Counts as of August 16, 2026. Compiled from 6 public datasets.
North America hubEvery rule, deadline, technology, and case across both countries.
United StatesFederal MCLs plus the standard in all 50 states and DC.
CanadaHealth Canada Objective plus every province and territory.
Data not supplied by Nelson. Every figure comes from public regulator records published by the agencies cited. Nelson compiles, maps and links the records, and does not create, verify, adjust or own the underlying data. This hub is a free public resource published to share knowledge. Every figure traces to a government dataset a reader can download and re-check, the sources are listed in the methodology, and nothing here is gated behind a form. Dataset compilation copyright 2026 Nelson Environmental Remediation Ltd. All rights reserved. Source attribution required for reuse. Data licence and citation.
Three views, three kinds of record, three different questions
A property is a place where contamination sits in soil or groundwater and someone carries the cleanup obligation. A station is a place where a sample was taken. A water system is a place where treated water was tested at the tap. One property can sit upstream of many stations and many water systems, and many water systems have no identified source property at all. Mixing the three would inflate the picture, so each view stands on its own and each layer inside it states its own source and its own limit.
View one, the default
Contaminated properties to remediate
US DoD installations, US Superfund sites with PFAS detected, Canadian federal sites with PFAS recorded, and the full Canadian federal inventory of sites with an open obligation. These are places with land, an owner, and a cleanup responsibility on the public record.
View two
Measured PFAS in the environment
Monitoring stations from the Water Quality Portal run by USGS, EPA, and the National Water Quality Monitoring Council, where a PFAS analyte was sampled and reported in groundwater, rivers, streams, lakes, or sediment. A station is a measurement point, not a property and not a water supply.
View three
Drinking water at the tap
Treated drinking water results from EPA UCMR 5, reported in ng/L by public water system. This view shows where PFAS has reached the tap. It does not show where the source contamination sits in the ground.
The layers inside each view
United States drinking water
Drinking water results from EPA UCMR 5. Each pin is a public water system, placed at the ZIP code centroid it serves. The colours show how the highest detected compound compares to the 2024 federal drinking water limit. This layer tells you where PFAS has reached the tap, not where the source contamination sits in the ground.
United States DoD installations
Department of Defense installations where PFAS assessment or remediation is proceeding or complete. These are source-contamination sites, not drinking water systems. Nearby UCMR 5 results are summarised in each popup so you can see how base-sourced plumes may connect to surrounding water systems.
United States Superfund sites
Superfund sites where EPA has detected PFAS in site media such as soil and groundwater, taken from the EPA PFAS Analytic Tools. Each pin is a property with a federal cleanup programme and a responsible party attached, which makes this the most complete contaminated-property layer in the set.
Canada
Federal contaminated site records from the Treasury Board inventory. Each pin is a federal property where PFAS has been recorded, and the media filter shows whether it was detected in groundwater, soil, sediment, or surface water. This layer points to the source contamination, not treated drinking water.
Canada, all federal contaminated sites
The full Treasury Board inventory across every contaminant class, drawn for sites that still carry an open federal obligation, plus every PFAS tagged site. It shows the scale of federal cleanup work in Canada beyond PFAS alone. It overlaps the PFAS tagged Canadian layer by design, so the two counts stay separate.
North America, PFAS monitoring stations
Water Quality Portal stations where a PFAS analyte was measured and reported, grouped by groundwater, surface water, facility outfall, or unclassified. Presence of a station means someone sampled there. It does not by itself mean PFAS was detected above a limit.
How to search properties, monitoring stations, water systems, and affected media
Start with the view that matches your question, then filter inside it. Monitoring stations can be narrowed by the water body or well type they sit in. Canadian federal sites can be narrowed by affected medium. Filter US results by federal exceedance, mixture Hazard Index, or any detection, then narrow by state or search a system by name. Every US pin opens the compound-level results EPA published for that system. Canadian pins open the federal inventory record for that site. DoD installation pins show cleanup status and nearby water system summaries. Superfund pins show NPL status, site type, and a link to the EPA site record. Use the layer control at the top right of the map to switch any layer on or off.
What this map counts, and what it cannot count yet
The remediation view is built from the national datasets that publish confirmed PFAS findings at property level: the Department of Defense installation record, EPA Superfund sites with PFAS detected in site media, and the Canadian Federal Contaminated Sites Inventory. Those are the major reporting sources with consistent national coverage. They are a floor, not a total.
A large share of North American PFAS impacted property sits outside them. State and provincial cleanup registers, RCRA corrective action files, airport and fire training grounds, industrial sites under private assessment, and voluntary cleanup programmes are held in dozens of separate regional systems with different reporting thresholds, different analyte lists, and no shared site identifier. Those records are real, but they cannot be added together into one honest national number, so the map does not pretend to. Every count shown is traceable to a named federal source and can be downloaded and checked.
Read the totals as confirmed and published, not complete. Absence of a pin means no federal record has been published for that property. It does not mean the property is clean.
Canada: federal sites with PFAS in soil, groundwater, and sediment
Canada runs no national drinking water monitoring programme equivalent to UCMR 5, so there is no Canadian dataset of PFAS concentrations by water system. The defensible national record for land remediation is the Federal Contaminated Sites Inventory, which lists 24,426 federal sites and identifies the contaminant classes recorded at each one. 97 of those sites carry PFAS, most of them airports and military installations where fluorinated firefighting foam was used in training. Use the media filter above the map to see which sites recorded groundwater, soil, sediment, or surface water. Concentrations are not published in the inventory, so this layer shows where PFAS has been recorded, not how much.
Province or territory
Sites with PFAS recorded
Still active
Largest custodian
Ontario
16
16
National Defence (7)
Alberta
12
9
Parks Canada Agency (5)
Saskatchewan
11
8
National Defence (8)
British Columbia
10
8
MOT (7)
Newfoundland and Labrador
10
10
MOT (8)
Manitoba
9
7
National Defence (6)
Québec
8
8
MOT (6)
Nova Scotia
6
5
National Defence (5)
New Brunswick
5
5
MOT (4)
Northwest Territories
3
3
MOT (3)
Nunavut
3
3
MOT (2)
Prince Edward Island
2
2
MOT (2)
Yukon
2
1
MOT (2)
Source: Treasury Board of Canada Secretariat, Federal Contaminated Sites Inventory, retrieved 2026-08-13. Published under the Open Government Licence - Canada. Open data record.
States with the most systems above a federal limit
State
Above a limit
Systems with detections
California
164
235
Florida
156
189
New Jersey
155
173
Pennsylvania
116
169
North Carolina
114
144
Massachusetts
104
141
Texas
102
607
Alabama
78
116
South Carolina
67
88
Ohio
59
141
New York
51
96
Georgia
42
77
Tennessee
37
86
Connecticut
36
41
Washington
34
65
Highest reported results relative to the federal limit
Water system
State
Times the limit
Nashville, Town Of
NC
123x
Running Springs Water District
CA
59x
Collegeville Trappe Joint Pwd
PA
59x
Potrero Elementary School
CA
47x
Lubeck Psd
WV
45x
Artondale Water System
WA
38x
Emmaus Borough Public Water
PA
38x
New Martinsville
WV
30x
Pequenakonck Elementary School
NY
28x
Yeshiva Farm Settlement
NY
27x
Raynham Center Water District
MA
23x
City Of Grand Prairie
TX
21x
Orangewood Water System
FL
20x
City Of Oxford
MS
18x
Bayleaf Master
NC
15x
PFAS by state and province
Each page carries the same federal citations as this map, the standard that jurisdiction applies, and, for US states, the number of water systems above a federal limit in the EPA UCMR 5 results.
United States
Alabama
Alaska
Arizona
Arkansas
California
Colorado
Connecticut
Delaware
District of Columbia
Florida
Georgia
Hawaii
Idaho
Illinois
Indiana
Iowa
Kansas
Kentucky
Louisiana
Maine
Maryland
Massachusetts
Michigan
Minnesota
Mississippi
Missouri
Montana
Nebraska
Nevada
New Hampshire
New Jersey
New Mexico
New York
North Carolina
North Dakota
Ohio
Oklahoma
Oregon
Pennsylvania
Rhode Island
South Carolina
South Dakota
Tennessee
Texas
Utah
Vermont
Virginia
Washington
West Virginia
Wisconsin
Wyoming
Canada
Alberta
British Columbia
Canada (Federal)
Manitoba
New Brunswick
Newfoundland and Labrador
Northwest Territories
Nova Scotia
Nunavut
Ontario
Prince Edward Island
Québec
Saskatchewan
Yukon
What is PFAS?
PFAS stands for per- and polyfluoroalkyl substances, a family of several thousand synthetic chemicals built around the carbon-fluorine bond. That bond resists heat, water, and oil, which made the compounds useful in firefighting foam, non-stick cookware, stain-resistant fabric, food packaging, and industrial processing. The same stability means they do not degrade in soil, water, or the human body under normal conditions, which is why they are commonly called forever chemicals.
The 2024 EPA National Primary Drinking Water Regulation set enforceable limits of 4 parts per trillion for PFOA and PFOS, 10 parts per trillion each for PFHxS, PFNA, and HFPO-DA, and a Hazard Index of 1 for the four-compound mixture. Systems must finish initial monitoring by April 2027 and meet the limits by April 2029. Canada takes a different approach: Health Canada published an objective of 30 nanograms per litre for the sum of 25 PFAS compounds in 2024.
US state limits
Canadian standards
How PFAS is removed and destroyed
Built from published government records, not estimates
Where PFAS records and military property records overlap
410 pairings where a PFAS-assessed installation and a defence property record describe the same ground. Firefighting foam history is the usual reason these two record sets land on the same coordinates, which is why the pairing is worth checking. Each row links to the defence property file behind the military hub. A pairing shows that two agencies published records at the same location. It is not a finding of foam use or of contamination at either record.
PFAS record
Military property record
Where
Apart
Pairing
Navy, Active
SAN NICHOLAS ISLAND NAVAL RES.VENTURA, Properties without projects
California
same point
Strong
Army, National Guard
FORT RUGERHONOLULU, Properties with all projects at site closeout
Hawaii
same point
Strong
DND, Halifax
Dockyard (1015) - Underwater Repair building (D53)Active
Nova Scotia
same point
Strong
DND, Halifax
Shearwater (210) - Fire Fighting Training AreaActive
Nova Scotia
0.2 km
Strong
Air Force, National Guard
SALT LAKE CITY ARMY AIR BASESALT LAKE, Properties without projects
Utah
0.2 km
Strong
Air Force, Active
AF PLANT #42, K9 ANXLOS ANGELES, Properties without projects
California
0.2 km
Strong
Army, National Guard
LOS ALAMITOS RADAR BOMB SCORINORANGE, Properties without projects
California
0.3 km
Strong
DND, Moose Jaw No. 161
15 Wing EME Shop Test Site 1Active
Saskatchewan
0.3 km
Strong
DND, Moose Jaw No. 161
15 Wing B58 & EME Shop Test Site 2Active
Saskatchewan
0.3 km
Strong
DND, Moose Jaw No. 161
15 Wing EME Shop Test Site 1Active
Saskatchewan
0.3 km
Strong
Air Force, Active
MACDILL MIL AFHILLSBOROUGH, Properties without projects
Florida
0.4 km
Strong
Army, Active
WHEELER ASPHALT PLANTHONOLULU, Properties without projects
Hawaii
0.4 km
Strong
Air Force, Active
DOBBINS DISPOSAL #9COBB, Properties without projects
Georgia
0.4 km
Strong
Navy, Active
SAN DIEGO MFG PL AX DPCSAN DIEGO, Properties without projects
California
0.4 km
Strong
Air Force, National Guard
ST. LOUIS ARSENALST LOUIS CITY, Properties without projects
Missouri
0.4 km
Strong
Air Force, Active
ANDREWS AFBPRINCE GEORGE'S, Properties without projects
Maryland
0.5 km
Strong
Air Force, National Guard
ELLINGTON FIELD-US COAST GUARDHARRIS, Properties without projects
Texas
0.5 km
Strong
Army, National Guard
ELLINGTON FIELD-US COAST GUARDHARRIS, Properties without projects
Texas
0.5 km
Strong
Air Force, Active
LITTLE ROCK DROP AXPULASKI, Properties without projects
Arkansas
0.5 km
Strong
Army, National Guard
MARTINDALE ARMY AIRFIELDBEXAR, Properties without projects
Texas
0.6 km
Strong
Navy, BRAC
NAVAL AIR STATION (WILLOW GROVE)MONTGOMERY, Properties without projects
Pennsylvania
0.6 km
Strong
Air Force, Active
BUCKLEY ANG BASEDENVER, Properties without projects
Colorado
0.6 km
Strong
Navy, Active
GREAT LAKES NTC-MISCELLANEOUS PARCELSLAKE, Properties without projects
Illinois
0.6 km
Strong
DND, Dundurn No. 314
Dundurn Fire HallActive
Saskatchewan
0.6 km
Strong
DND, Dundurn No. 314
Dundurn FFTAActive
Saskatchewan
0.6 km
Strong
Each PFAS record is matched to the nearest military property record in the same state or province within 25 km, scored on shared distinctive name terms and distance. High means shared name terms within 8 km. Medium means shared name terms within 25 km, or no shared terms within 3 km. Low is everything else that still met the distance test. A match shows that two public records describe the same ground. It is not a finding of AFFF use or of contamination at either record.
Drinking water results are the signal. The source is usually upstream.
The US drinking water results on this map show where PFAS has already reached public supply. Those results are a leading indicator. The source is usually upstream: firefighting foam at an airport or military base, industrial discharge, or a legacy landfill. This hub tracks both, so the tap-level result can be read against the source-area record.
Filtration protects drinking water, and it concentrates PFAS into spent carbon, loaded resin, and reject brine. Excavation moves contaminated soil to a landfill, where the liability travels with it. Ending the problem means breaking the carbon-fluorine bond, which is why destruction technologies are the subject of active independent testing, including the NATO PFAS test bed. Those results, and the measurement methods behind them, are published rather than summarised.
Independent PFAS destruction testing
Destruction methods compared
Dataset schema
Field definitions for every column in the remediation exports
Each column in the DoD and Superfund CSV downloads is defined below: what it holds, where the value came from, and the reading that would be wrong. The same reference is available as a single CSV so an analyst can audit the exports without opening the map.
United States: DoD PFAS installations
One row per military installation with recorded PFAS assessment or cleanup activity.
Export file:
pfas-us-dod-installations-YYYY-MM-DD.csv
Licence:
CC BY 4.0
Publisher:
US Department of Defense installation record, joined to EPA UCMR 5 by TapWaterData. Source record
Column
Type
Populated
Definition and value source
Installation ID
text
always
Stable identifier for the installation within this dataset.Value source. Publisher record key.Read with care. This is not a DoD-wide installation code and should not be joined to other DoD systems on its own.
Installation
text
always
Installation name as published.Value source. DoD installation list.Read with care. Names change after realignment or closure, so historic names may differ.
Branch
text
always
Service branch responsible for the installation, such as Air Force, Army, or Navy.Value source. DoD installation list.
Component
text
usually
Component within the branch, such as active, reserve, or National Guard, which usually determines who holds the cleanup obligation.Value source. DoD installation list.
State
text
always
State or territory containing the installation.Value source. DoD installation list.
Cleanup status
text
usually
Stage the DoD reports for PFAS work at the installation, such as preliminary assessment, site inspection, remedial investigation, or remedial action.Value source. DoD PFAS assessment reporting.Read with care. Status describes programme stage, not the extent of contamination. An early stage does not mean a small problem.
Systems nearby
integer
always
Count of public water systems in the UCMR 5 dataset located within the proximity radius used by the publisher.Value source. Proximity join between the installation coordinates and UCMR 5 systems.Read with care. A proximity join is a distance calculation only. It is not a finding that the installation affected those systems.
On-base systems
integer
always
Count of those nearby systems that serve the installation itself.Value source. Proximity join, flagged by the publisher.
Nearby systems with detection
integer
always
Count of nearby systems that reported at least one PFAS compound at or above the EPA reporting limit.Value source. EPA UCMR 5 occurrence results for the joined systems.Read with care. Detection is not attribution. The source of a detection is not established by this field.
Nearby systems exceeding MCL
integer
always
Count of nearby systems whose maximum reported value for a regulated compound is above the 2024 federal maximum contaminant level.Value source. EPA UCMR 5 results compared to the federal MCL.Read with care. UCMR 5 systems report a maximum value, not a running annual average, so this is not a compliance determination.
Latitude
decimal degrees
always
Installation centroid latitude, WGS 84.Value source. Publisher coordinates.Read with care. A centroid marks the installation, not a sample point or a plume boundary.
Longitude
decimal degrees
always
Installation centroid longitude, WGS 84.Value source. Publisher coordinates.
United States: Superfund sites with PFAS detected
One row per Superfund site where PFAS has been detected in site media such as soil, groundwater, sediment, or surface water.
Export file:
pfas-us-superfund-sites-YYYY-MM-DD.csv
Licence:
US Government public domain
Publisher:
US EPA PFAS Analytic Tools, drawn from the Superfund Enterprise Management System. Source record
Column
Type
Populated
Definition and value source
EPA site ID
text
always
EPA site identifier in SEMS, the key used across EPA Superfund reporting.Value source. SEMS site record.
Site name
text
always
Site name as recorded by EPA.Value source. SEMS site record.Read with care. Site names often reflect a historic operator, so the current property owner may carry a different name.
City
text
usually
Nearest city or place recorded for the site.Value source. SEMS site record.
County
text
usually
County containing the site.Value source. SEMS site record.
State
text
always
State or territory containing the site.Value source. SEMS site record.
EPA region
integer
usually
EPA administrative region, 1 through 10, which identifies the regional office overseeing the site.Value source. SEMS site record.Read with care. Blank where EPA has not assigned a region in the published extract.
NPL status
text
always
National Priorities List standing, such as final, proposed, deleted, or not on the NPL, which indicates the federal cleanup track the site sits on.Value source. SEMS site record.Read with care. Deleted means the listed remedy is complete, not that PFAS work is complete.
On NPL
yes/no
always
Yes where the NPL status is final or proposed. Provided as a filter convenience.Value source. Derived from NPL status.
Site type
text
usually
Whether the site is a federal facility or a private party site, which usually determines who funds the cleanup.Value source. SEMS site record.
Latitude
decimal degrees
always
Site latitude, WGS 84.Value source. EPA site coordinates.Read with care. Coordinates mark the property record, not a specific sample point.
Longitude
decimal degrees
always
Site longitude, WGS 84.Value source. EPA site coordinates.
EPA site page
url
always
Link to the public EPA record for the site, where the full site history can be checked.Value source. Constructed from the EPA site identifier.
Data methodology
How this map was built, what it covers, and where it stops
Public agency records, compiled by Nelson.
The map is drawn from four public government datasets: US EPA drinking water results, US Department of Defense installation records, EPA Superfund sites with PFAS detected in site media, and the Canadian federal contaminated sites inventory. Visitors can check the underlying records themselves. Nothing here is modelled or estimated. It is a snapshot of reported occurrence, not a health advisory, a compliance determination, or a substitute for a utility's own Consumer Confidence Report.
United States: source and timing
All concentrations come from the US EPA Fifth Unregulated Contaminant Monitoring Rule public occurrence dataset, January 2026 release. UCMR 5 required every large public water system (serving more than 10,000 people) and a representative sample of small systems to test for 29 PFAS compounds between January 2023 and December 2025. Systems report the maximum value detected during their monitoring period, so the map reflects the highest reading a system recorded, not a running annual average. This is a drinking water dataset. It contains no soil, sediment, or groundwater results.
View EPA UCMR 5 source data
What each US pin shows
Each marker represents one public water system that reported at least one PFAS compound at or above the EPA reporting limit. The popup lists the maximum concentration recorded for each compound, measured in nanograms per litre, which is the same unit as parts per trillion. The colour shows how the worst single compound compares to the 2024 federal maximum contaminant level. Because these are treated drinking water samples, a pin marks a water system, not a contaminated property.
United States: Department of Defense PFAS installations
The DoD layer plots military installations where the Department of Defense has recorded PFAS assessment or remediation activity. Data comes from the DoD PFAS installation list, joined to nearby EPA UCMR 5 public water system results by TapWaterData under a CC BY 4.0 licence. Each popup shows the installation name, branch, component, state, cleanup status, and a summary of water systems within a reasonable radius. This layer marks source-contamination sites, not drinking water systems, and the nearby water summaries are a proximity join, not a proven attribution of contamination.
View TapWaterData military base PFAS data
United States: Superfund sites with PFAS detected in site media
The Superfund layer comes from the EPA PFAS Analytic Tools, which publish the Superfund sites in EPA's Superfund Enterprise Management System where PFAS has been detected in site media such as soil, groundwater, sediment, or surface water. Each popup shows the EPA site identifier, National Priorities List status, whether the site is a federal facility or a private party site, the EPA region, and a link to the EPA site record. This is the closest thing the United States publishes to a national contaminated land layer for PFAS, because every one of these properties carries a cleanup obligation. Coordinates come from the EPA site record and mark the property, not a specific sample point.
View the EPA PFAS Analytic Tools
Coverage and gaps
Large systems. All large systems were required to monitor, so coverage is essentially complete for the 29 regulated PFAS compounds.
Small systems. Only a statistical sample of small systems was required to participate. Many small systems have not yet reported, so absence from the map does not prove absence of PFAS.
Private wells. Private wells, bottled water, and non-community systems are not part of UCMR 5 and are not shown.
US soil and groundwater. There is no single national US database of PFAS in soil or groundwater equivalent to UCMR 5. The closest available view combines the DoD installation assessment layer with EPA Superfund sites where PFAS has been detected in site media. Both are major reporting sources with national coverage, and both are floors rather than totals.
Sites held in regional systems. State and provincial cleanup registers, RCRA corrective action files, airport and fire training grounds, industrial sites under private assessment, and voluntary cleanup programmes hold a large volume of PFAS impacted property. They sit in dozens of separate systems with different reporting thresholds, different analyte lists, and no shared site identifier, so they cannot be reconciled into a single national figure without inventing one. They are excluded rather than estimated.
Suspected versus confirmed. Sites where PFAS use is likely but no sampling has been published, such as many certificated airports and fire training areas, are not plotted. The map carries confirmed published findings only.
Canada. Canada has no equivalent national drinking water sampling programme, so no Canadian water systems appear in the UCMR 5 layer. Canadian coverage comes from the federal site inventory described below, which records soil, groundwater, sediment, and surface water. Provincial registers are separate and are not included.
Canada: source, timing, and why it matters for remediation
The Canadian layer comes from the Federal Contaminated Sites Inventory, maintained by the Treasury Board of Canada Secretariat and published as open data. The inventory records every contaminated site on federal land, the custodian department responsible for it, the contaminant classes found there, the affected media, the federal priority classification, and the remediation step reached. Nelson filtered the full inventory on the inventory's own contaminant code 73, "PFAS (per and poly fluoroalkyl substances)", and kept only those records, all of which publish coordinates. Because the inventory records media, this layer is directly relevant to soil and groundwater remediation work.
No concentrations. The inventory does not publish sample values, so Canadian pins show that PFAS has been recorded at a site, not how much was measured. Canadian pins are shaded by federal priority classification, not by exceedance.
Federal land only. Sites under provincial, municipal, or private jurisdiction are outside the inventory. Provincial contaminated site registries are separate and are not merged here.
Site coordinates. Coordinates identify the federal property, not a specific well, plume, or sampling point.
Reporting lag. Custodian departments update records on their own schedules, and PFAS is a recent addition to many site profiles. Sites where PFAS has been sampled but not yet entered will not appear.
Why other Canadian lists are not used. Media compilations of contaminated sites, including recent national news investigations, are largely derived from this same federal inventory and cover all contaminant types rather than PFAS specifically. Nelson works from the primary federal record so every pin traces back to a citable government entry.
View the Federal Contaminated Sites Inventory
Known limitations
US drinking water layer is water only. The EPA UCMR 5 layer shows treated public water system results. It does not show soil, groundwater, sediment, or industrial source locations. Nelson has added a separate DoD installation layer as the first US soil and groundwater signal; EPA Superfund/CERCLA records will follow.
Location approximation. US pins are placed at the centroid of the first ZIP code a system serves, not at a well, intake, or treatment plant. Large systems can span multiple counties. Canadian pins sit at the federal property coordinate, not a specific sampling point.
Not a compliance ruling. Exceeding a 2024 MCL in monitoring data is not the same as a violation. Compliance is based on a running average and the formal schedule that ends in April 2029. EPA proposed changes to that rule on 18 May 2026, covering a 2031 compliance date for PFOA and PFOS and rescission of the other four standards. Neither proposal is final, so the 2024 limits still apply.
Snapshot, not trend. The map shows the highest reported value, not whether a concentration is rising or falling over time.
No modelling or estimation. Nelson Environmental Remediation did not model, fill, or estimate any values. If the EPA dataset does not list a detection for a system, that system does not appear.
How the extraction can be reproduced and checked
United States. Every value is the maximum result a system reported in UCMR5_All.txt for a given PFAS compound, with the sign field set to a measured detection. Non-detects and the lithium results in the same file are excluded. Reported micrograms per litre are multiplied by 1,000 to give nanograms per litre. No other transformation is applied. 3,539 systems reported at least one detection nationally. 87 of them were held back because EPA published no serviced ZIP code, so 3,452 systems are plotted. The counters above report the national figures, and the map itself shows the plotted subset.
Canada. Sites are selected on the inventory's own contaminant code 73, "PFAS (per and poly fluoroalkyl substances)". 97 of the 24,426 sites in the inventory carry that code, and all of them publish coordinates, so none were dropped. Names, custodians, classifications, statuses, and affected media are reproduced from the inventory record without editing.
Seven Canadian sites left off. Seven further inventory records mention PFAS in the site name, for example fire training areas at 17 Wing Winnipeg and Victoria Airport, but carry no contaminant entry at all in the published data. They are not plotted, because plotting them would mean inferring a contaminant the Government of Canada has not recorded.
Geocoding. US pins use published ZIP code centroids to place a system on the map. The concentrations themselves are never geocoded, adjusted, or interpolated.
Independently re-checked. Both extractions were re-run against the raw source files by a second pass that shared no code with the build script, and the record counts and values matched exactly.
Check this map against the raw government files
These are the federal sources themselves, not Nelson's extract. Download them and the figures on this page should reconcile line for line.
US EPA UCMR 5 occurrence data The January 2026 release. The file used here is UCMR5_All.txt inside the published data zip.
Federal Contaminated Sites Inventory Treasury Board of Canada Secretariat. Search by contaminant to reproduce the PFAS selection.
Inventory bulk download on Open Government The full XML record set (fcsi-rscf.zip), published under the Open Government Licence Canada.
Nelson's US extract, JSON and Canadian extract, JSON The exact files this map reads, so a reader can diff them against the federal originals.
Full CSV copies are available from the map toolbar above, both the filtered view and every mapped US system in one file.
If you find a record that does not match its source, tell Nelson and it will be corrected or removed. Verify any result against the source dataset and your water utility's Consumer Confidence Report before making a health, compliance, or remediation decision. Last regenerated: 2026-08-13.
Embed this map on your site
Free for newsrooms, agencies, utilities, universities and consultants. Paste the snippet into any page. The widget stays current as the underlying datasets are refreshed, and it carries a hyperlinked source line back to Nelson.
North American PFAS contamination map
Drinking water systems, remediation sites and monitoring stations, with the same layer toggles as this page.
The snippet includes the source line, so the credit travels with the widget. Preview it at /embed/pfas-map.
Attribution
Keep the source line intact. It reads “Source: Nelson Environmental Remediation, 2026” and links to this hub. Full terms, including what needs written permission, are on the data licence page.
Counts as of August 16, 2026. Source datasets refreshed July 11, 2026 to August 16, 2026.
Cite this dataset
Evidence and confidence
What each number on this page is counting, how certain it is, and where it came from.
Confidence basis: Counted directly from the published regulator record with no modelling.Known uncertainty: UCMR 5 monitoring ran in phases and the occurrence file is republished periodically, so systems sampled later appear only when the extract is regenerated.CitationsEPA Fifth Unregulated Contaminant Monitoring Rule
Talk to a specialist
Found PFAS near a site you manage?
Tell us where, and a Nelson specialist will walk you through what the data shows and what permanent destruction would involve.
PFAS questions
Search the questions below for a compound, a dataset, or a jurisdiction. Answers cover PFAS itself and the data behind this map.
15 questions. Type to filter by keyword, dataset, or compound.
PFAS basics
What is PFAS?
PFAS are per- and polyfluoroalkyl substances, a family of thousands of synthetic chemicals built around carbon-fluorine bonds. That bond is one of the strongest in organic chemistry, so the compounds resist heat, water, and oil, and they do not break down under normal environmental conditions. They are used in firefighting foam, non-stick and stain-resistant coatings, food packaging, and many industrial processes. Because they persist, they are commonly called forever chemicals.
How do I find out if PFAS is in my drinking water?
Search this map for your public water system. It shows the maximum concentration each system reported for each PFAS compound during EPA UCMR 5 monitoring, measured in nanograms per litre, which is the same as parts per trillion. If your system is not listed, it either reported no detections or was not part of the monitoring sample. Your water utility publishes an annual Consumer Confidence Report with its own results.
What are the EPA limits for PFAS in drinking water?
The 2024 National Primary Drinking Water Regulation sets enforceable limits of 4 parts per trillion for PFOA and PFOS, 10 parts per trillion each for PFHxS, PFNA and HFPO-DA (GenX), and a Hazard Index of 1 for mixtures of PFHxS, PFNA, HFPO-DA and PFBS. Public water systems must complete initial monitoring by April 2027 and meet the limits by April 2029. On 18 May 2026 EPA proposed extending the PFOA and PFOS compliance date to 2031 and rescinding the PFHxS, PFNA, HFPO-DA and Hazard Index standards. Neither proposal is final, so the 2024 rule still controls.
Does filtration remove PFAS permanently?
Granular activated carbon, ion exchange resin, and reverse osmosis capture PFAS from water, which protects the people drinking it. The PFAS is still present, concentrated in spent media, resin, or reject brine, and it becomes a waste stream someone has to manage. Permanent removal requires destruction of the carbon-fluorine bond, which is why high-temperature thermal treatment and other destruction technologies are being tested for PFAS-loaded media and soil.
Where does the data on this map come from?
Every value comes from the US EPA Fifth Unregulated Contaminant Monitoring Rule public occurrence dataset, the January 2026 release. No values are modelled, estimated, or supplied by Nelson Environmental Remediation.
Data and sources
What data does the Nelson PFAS contamination map show?
It shows PFAS occurrence across the United States and Canada from four public datasets: EPA UCMR 5 drinking water monitoring results, US Department of Defense installation records, EPA Superfund sites with PFAS detected in soil or groundwater, and Canadian federal contaminated sites with PFAS listed as a contaminant of concern.
Where does the US PFAS drinking water data come from?
From the US EPA Fifth Unregulated Contaminant Monitoring Rule public occurrence dataset. Each mapped public water system shows the maximum concentration it reported for each PFAS compound, in nanograms per litre, which is the same as parts per trillion. No value is modelled or estimated.
Where does the Canadian PFAS data come from?
From the Government of Canada Federal Contaminated Sites Inventory, filtered to sites where PFAS or related perfluorinated compounds are recorded as a contaminant of concern. It covers federal land only. Provincial, territorial, and private sites are outside that inventory and are not shown.
How many water systems have reported PFAS detections?
The map counts every public water system with at least one PFAS detection in the UCMR 5 record, and separately counts systems reporting a result above an EPA maximum contaminant level. Both counters read live from the compiled file, so the number on screen matches the dataset vintage shown in the methodology section.
Which PFAS compounds are covered by the data?
UCMR 5 monitors 29 PFAS compounds, including PFOA, PFOS, PFHxS, PFNA, HFPO-DA (GenX), and PFBS. The map reports the maximum reported concentration per compound per system, and flags results above the 2024 National Primary Drinking Water Regulation limits.
What do the EPA PFAS drinking water limits require?
The 2024 rule sets enforceable limits of 4 parts per trillion for PFOA and PFOS, 10 parts per trillion each for PFHxS, PFNA and HFPO-DA, and a Hazard Index of 1 for mixtures. Public water systems complete initial monitoring by April 2027 and meet the limits by April 2029. Later proposals to change those dates are not final, so the 2024 rule still controls.
Does a detection on the map mean the water is unsafe?
No. A detection means the compound was measured above the reporting limit during monitoring. Whether a result exceeds a regulatory limit is shown separately on the map. Anyone assessing risk should read the utility's annual Consumer Confidence Report alongside the federal record.
Can I download the PFAS datasets behind the map?
Yes. The US and Canadian extracts the map reads are published as JSON, filtered and full CSV exports are available from the map toolbar, and every federal source is linked from the methodology section. The hub is a free public resource for knowledge sharing.
How current is the PFAS data?
The map reports the generation date of the compiled files. UCMR 5 monitoring ran in phases and the public occurrence file is republished periodically, so the map is a snapshot of the published record. Systems added in a later release appear when the extract is regenerated.
Does Nelson supply or verify the PFAS data?
No. Every value comes from a public government dataset. Nelson compiles and visualises the published record, names every source, and keeps the extracts downloadable so a reader can check them against the federal originals.
Qualified enquiry
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Send the contaminant, approximate tonnage, and jurisdiction. We will come back with the treatment path that fits and what it takes to verify closure.
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Cite this dataset
Cite this datasetFree to use with credit. Pick a format, copy it, and the link back to the source comes with it.Plain textArticles, reports, slides and social posts. CopyNorth American PFAS contamination map. Nelson Environmental Remediation Ltd., 2026. Counts as of August 16, 2026. https://nelsonremediation.com/pfas-contamination-mapAPAAcademic papers and formal references. CopyNelson Environmental Remediation Ltd. (2026). North American PFAS contamination map [Data set]. Counts as of August 16, 2026. Retrieved from https://nelsonremediation.com/pfas-contamination-mapWeb linkDrops straight into a page with the backlink in place. Copy<p>Source: <a href="https://nelsonremediation.com/pfas-contamination-map" rel="noopener">North American PFAS contamination map</a>, Nelson Environmental Remediation Ltd., 2026. Counts as of August 16, 2026. Compiled from public regulator records, <a href="https://nelsonremediation.com/data-licence" rel="license noopener">licence terms</a>.</p>BibTeXReference managers and research tooling. Copy@misc{nelson2026pfascontaminationmap,
title = {North American PFAS contamination map},
author = {{Nelson Environmental Remediation Ltd.}},
year = {2026},
note = {Data set. Compiled from public regulator records. Counts as of August 16, 2026},
url = {https://nelsonremediation.com/pfas-contamination-map}
}Source attribution required. Reuse, republication, redistribution or model training on this compilation must credit Nelson Environmental Remediation Ltd. and link to nelsonremediation.com. Full licence terms.Close
Does a detection on the map mean the water is unsafe?
No. A detection means the compound was measured above the reporting limit during monitoring. Whether a result exceeds a regulatory limit is shown separately on the map. Anyone assessing risk should read the utility's annual Consumer Confidence Report alongside the federal record.