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Review government records associated with Norwalk, Connecticut. Open a section to see source records, coverage and dates. These city-level results do not establish exposure at a home or identify your water provider.
Toxin Scout summarizes public records from government and public datasets. Data can be delayed, incomplete, approximate, matched at non-parcel levels, or have accuracy problems as a result of this product's beta status, so verify important findings against the linked source records.
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Preparing Norwalk environmental records...
Counts describe the records shown, not a complete city inventory. Some sources include nearby locations.
Drinking water compliance, PFAS records, natural water body health, discharge permits, and water-quality monitoring records for Norwalk.
Public water-system records for Norwalk, CT from EPA SDWIS.
Norwalk First Taxing District
Active health-based drinking-water issue detected in EPA SDWIS.
Reviewed: active/open records as of Q1 2026
City listed in EPA records · Serves 40,256 people
Data from EPA SDWIS
PFAS screening separates EPA UCMR5 drinking-water monitoring from nearby DoD PFAS investigation-site records; EPA samples shown are from Nov 2023 to Sep 2024.
Drinking Water PFAS Monitoring
EPA UCMR5 samples public water systems. These results are separate from nearby PFAS cleanup or investigation-site records.
7 PFAS sample results above EPA limits
Sample period: Nov 2023 to Sep 2024
UCMR5 results are sampled by public water system, not every household. Confirm your water provider before treating these as tap-water results for a specific address.
| Chemical | Concentration (µg/L) | EPA Limit (µg/L) | Sample date | Over Limit |
|---|---|---|---|---|
| PFOS | 0.0112 | 0.0040 | 2024-06-25 | Yes |
| PFOA | 0.0095 | 0.0040 | 2024-06-25 | Yes |
| PFOS | 0.0089 | 0.0040 | 2024-04-02 | Yes |
| PFOA | 0.0079 | 0.0040 | 2024-04-02 | Yes |
| PFOA | 0.0043 | 0.0040 | 2023-11-01 | Yes |
| PFOA | 0.0042 | 0.0040 | 2024-08-14 | Yes |
| PFOA | 0.0041 | 0.0040 | 2024-09-10 | Yes |
PFAS detections below EPA limits.
Nearby PFAS Investigation Sites
DoD records are nearby site investigations, not Norwalk drinking-water detections. Record names come from the source database and can be broad.
No DoD PFAS investigation records shown for this report.
Water Body Impairment (ATTAINS) city records are temporarily unavailable.
NPDES permits regulate pollutant discharges into U.S. waterways. Facilities must report compliance quarterly.
No NPDES-permitted facility records with violations surfaced for this city report.
Reviewed: active/open records as of Q4 2025
Data from EPA ECHO
Reviewed: source records as of 2026
Air quality data from EPA monitoring stations, facility emissions inventories, and area-level air-quality designations in this city.
Air Quality Nonattainment Areas city records are temporarily unavailable.
Greenwich Point Park — Greenwich (Town of), Connecticut
Annual mean: 0.047 ppm · EPA standard: 0.07 ppm
Annual standard context: 11 exceedance days recorded in the reporting period
Reported: 2024
Usgs Lighthouse — Stratford (Town of), Connecticut
Annual mean: 0.047 ppm · EPA standard: 0.07 ppm
Annual standard context: 8 exceedance days recorded in the reporting period
Reported: 2024
White Plains
Annual mean: 0.042 ppm · EPA standard: 0.07 ppm
Annual standard context: 6 exceedance days recorded in the reporting period
Reported: 2024
Data from EPA AQS
Reviewed: source records as of Q4 2025
TRI releases are self-reported annual totals (calendar year 2024). Hover fugitive or stack for definitions.
Asml US Lp
Reported: 2024
King Industries Inc
Reported: 2024
Contaminated sites, waste facilities, cleanup records, and industrial operations in this city.
Sites listed on the National Priorities List (NPL) where releases or threatened releases of hazardous substances may endanger public health or the environment, as designated under CERCLA.
Open data source: Search EPA ECHO· 110060849462
Reported: Nov 2021
Brownfield sites are properties where redevelopment is complicated by the presence of hazardous substances.
Open data source: Search EPA ECHO3 sites with active cleanup or investigation status
5 Chestnut Street, Norwalk
Reported: Feb 2026
13 Day Street, Norwalk
Reported: Feb 2026
20 Monroe Street, Norwalk
Reported: Feb 2026
Facilities with hazardous-waste handler records under RCRA in the reviewed 5-mile city-center search area. Active handler status is separate from air, water, or other ECHO compliance violations, which are shown in their own sections.
Active RCRA handler records in the reviewed city search area
No release reports shown in this group.
Reviewed: active/open records as of 2018
Data from EPA UST Finder
Reviewed: reporting year 2024
Sites regulated by the Mine Safety and Health Administration, including mines, sand and gravel operations, and portable crushers. Status and type are from the MSHA Mine Data Retrieval System. Records with active/intermittent status dates older than 5 years are shown as older records rather than current active sites.
No records shown in this group.
Reviewed: status dates within last 5 years
Data from MSHA
Flood-map status, chemical accident risk, nuclear facilities, pipeline incidents, and community health indicators in this city.
FEMA's National Flood Hazard Layer maps flood risk. Properties in a Special Flood Hazard Area are required to carry flood insurance if they have a federally backed mortgage.
Coastal Special Flood Hazard Area — 1% annual chance of flooding with additional coastal wave action hazards and base flood elevation.
Risk Management Program records cover listed chemicals above EPA thresholds. Records may include historical registrations and do not confirm current operations or current chemical inventories.
Accident history is not established by these EPA ECHO facility records.
Reviewed: source records as of Q1 2026
Data from EPA ECHO
Reviewed: 2000-present