E. coli
Unresolved Drinking water rule (140) violation cited in 2024 (e. coli).
City · TRI 2024
Danbury, Connecticut Pollution
5 TRI facilities inside the city limits and 13 public water systems serving residents. In-city TRI releases fell meaningfully year over year (-17%). Toxic releases concentrations are up 20% since 2010.
FIPS 0918430 · population 86,456 · Fairfield County
Anomaly engine
Notable Signals
E. coli
Unresolved Drinking water rule (140) violation cited in 2024 (e. coli).
Contaminant 8000
Unresolved Revised Total Coliform Rule violation cited in 2025 (contaminant 8000).
Contaminant 8000
Unresolved Revised Total Coliform Rule violation cited in 2022 (contaminant 8000).
Showing the 4 most editorially weighted signals out of 16. Lower-severity signals fold into the chemical breakdown and history charts below.
Pollutant pathways
Danbury Pollutant Multi-Year Trends
PM2.5 annual mean (NAAQS 9 µg/m³ (annual))Health riskFine inhalable particles 2.5 micrometers or smaller. They travel deep into the lungs and into the bloodstream — linked to asthma, heart disease, stroke, and premature death.
PM2.5 annual mean (NAAQS 9 µg/m³ (annual)) concentrations have more than halved since 2010.
PM2.5 24-hour 98th percentile (NAAQS 35 µg/m³ (24-hour))Health riskFine inhalable particles 2.5 micrometers or smaller. They travel deep into the lungs and into the bloodstream — linked to asthma, heart disease, stroke, and premature death.
PM2.5 24-hour 98th percentile (NAAQS 35 µg/m³ (24-hour)) concentrations have more than halved since 2010.
Ozone 8-hour 4th-highest daily max (NAAQS 0.070 ppm (8-hour))Health riskGround-level ozone (smog) forms when vehicle and industrial emissions react in sunlight. Inflames the airways, triggers asthma attacks, and worsens heart and lung disease.
Ozone 8-hour 4th-highest daily max (NAAQS 0.070 ppm (8-hour)) concentrations are roughly unchanged from 2010.
NO₂ annual mean (NAAQS 53 ppb (annual))Health riskA tailpipe and combustion gas. Concentrates near busy roads and industrial sites; raises risk of airway inflammation, asthma, and lower respiratory infections in children.
NO₂ annual mean (NAAQS 53 ppb (annual)) concentrations have more than halved since 2010.
Lifetime cancer risk all pollutants (100 in a million (EPA elevated threshold))Health riskEPA-modeled added cancer cases per million residents from a lifetime of breathing local air toxics. EPA flags 100-in-a-million as elevated.
Single-vintage exposure modeling — EPA cadence is multi-year, so no trend line yet.
Formaldehyde ambient mean (0.077 µg/m³ (1-in-a-million URE))Health riskAn air toxic emitted by refineries, wood products, and combustion. EPA classifies it as a known human carcinogen — long-term inhalation raises cancer risk.
Single-vintage exposure modeling — EPA cadence is multi-year, so no trend line yet.
Benzene ambient mean (0.13 µg/m³ (1-in-a-million URE))Health riskAn air toxic from gasoline, refineries, and tobacco smoke. A known human carcinogen — chronic exposure is linked to leukemia and other blood cancers.
Single-vintage exposure modeling — EPA cadence is multi-year, so no trend line yet.
TRI air releases (5.1 fugitive + 5.2 stack)Health riskToxic chemicals reported by industrial facilities as released into the air — fugitive leaks plus smokestack emissions. Higher pounds means more inhaled exposure for nearby residents.
TRI air releases (5.1 fugitive + 5.2 stack) concentrations are roughly unchanged from 2010.
TRI water releases (5.3)Health riskToxic chemicals reported by industrial facilities as discharged to surface waters (rivers, lakes, the ocean). Affects fishing, recreation, and downstream drinking-water intakes.
TRI water releases (5.3) volumes here are too small to anchor a multi-year trend; YoY movement is still shown above.
TRI land + off-site releasesHealth riskToxic chemicals released to land on-site or transferred off-site for disposal — landfills, deep-well injection, and similar. Risks groundwater contamination over time.
TRI land + off-site releases volumes here are too small to anchor a multi-year trend; YoY movement is still shown above.
Greenhouse gases (GHGRP large emitters, through 2023)Health riskGreenhouse gases reported by large industrial emitters under EPA's GHGRP, in metric tons of CO₂ equivalent. Drives climate warming and the heat-related health effects that follow.
Greenhouse gases (GHGRP large emitters, through 2023) concentrations have fallen 14% since 2010.
Top facilities · TRI 2024
Largest Emitters Inside The City
| Facility | Top chemical | Total releases | YoY |
|---|---|---|---|
| Rsa Corp | MethanolHealth riskAcutely toxic if ingested or inhaled. Metabolizes to formaldehyde and formic acid, causing blindness and metabolic acidosis. (EPA) | 12k lb | -8% |
| Cs Clean Solutions INC. | Copper compoundsHealth riskInhaled copper fumes cause metal-fume fever; chronic ingestion above EPA's 1.3 mg/L action level damages the liver. (EPA) | 1k lb | -64% |
| Stanley Engineered Fastening LLCStanley Black & Decker | LeadHealth riskNeurotoxin. Even low childhood exposure impairs cognitive development; chronic adult exposure damages kidneys and the cardiovascular system. (EPA, ATSDR) | 665 lb | +13% |
| Bedoukian Research INC.Bedoukian Holdings INC | n-HexaneHealth riskPeripheral neurotoxin. Chronic exposure causes numbness and paralysis in the extremities. (ATSDR) | 252 lb | +26% |
| Federal Correctional InstitutionUS Department Of Justice | LeadHealth riskNeurotoxin. Even low childhood exposure impairs cognitive development; chronic adult exposure damages kidneys and the cardiovascular system. (EPA, ATSDR) | 1 lb | -67% |
Drinking water · SDWIS
Water Systems Serving Danbury
133 unresolved violations on the SDWIS record across utilities serving this city.
13
Utilities serving
64,443
Population served
24
Health-based · 5yr
133
Unresolved
| Water system | PWSID | Population served | Health-based · 5yr | Status |
|---|---|---|---|---|
| Elmwood Court, Llc Private | CT0090114 | 54 | 8 | UNRESOLVED |
| Brookfield Hills Condominium Unit Owners Private | CT0180171 | 144 | 6 | UNRESOLVED |
| Cedar Terrace Prop Owners Assn Private | CT0340141 | 66 | 4 | UNRESOLVED |
| 39 Hop Brook Rd - Apt Complex Private | CT0189971 | 36 | 2 | UNRESOLVED |
| Cornell Hills Assoc, Inc Private | CT0340181 | 108 | 1 | UNRESOLVED |
| Woodcreek Village Condominium Assn, Inc Private | CT0180201 | 72 | 1 | UNRESOLVED |
| Danbury Water Department Municipal | CT0340011 | 62,055 | 2 | Returned to compliance |
| Stony Hill Village Condominium Assn Private | CT0180251 | 392 | 0 | UNRESOLVED |
Showing the 8 systems with recorded health-based or unresolved violations. 5 additional systems are in compliance with no recorded health-based violations in the past 5 years and are not individually tabulated.
A public water systemis the regulated entity, not the city. EPA's SDWIS definition covers anything serving 25+ people for 60+ days a year or with 15+ service connections — that includes municipal utilities (City of Stockton), water districts, mobile home parks operating their own wells, schools, and small private subdivisions. Each system is independently monitored. Some systems serve multiple cities; some cities are served by many systems.
Equity context · ACS 2018-2022 · USEPA-clone EJ disparity
Who Lives In Danbury
Danbury, Connecticut (Census place block groups): 86,456 residents. Why we surface this →
10.6%
Low-income
55.3%
People of color
6.1%
Under age 5
14.8%
Over age 64
Source: Census ACS 2018-2022 (5-year) + USEPA-clone EJ blockgroup stats (raw indicators + EJ disparity mirror).
Health context
Co-Located Health Indicators
Modeled adult-prevalence estimates published by CDC PLACES, paired with this city's pollution and demographic context. Comparisons are ecological, not causal — pollution and disease prevalence covary at the area level, but the data does not attribute any individual's diagnosis to local exposure. How this section works →
Adult asthma (current)
10.3%
CDC PLACES · 2025 release · BRFSS 2022-2023
COPD prevalence
5.5%
CDC PLACES · 2025 release · BRFSS 2022-2023
Coronary heart disease
5.3%
CDC PLACES · 2025 release · BRFSS 2022-2023
Diabetes (diagnosed)
9.6%
CDC PLACES · 2025 release · BRFSS 2022-2023
Frequent mental distress
16.0%
CDC PLACES · 2025 release · BRFSS 2022-2023
PLACES uses BRFSS-modeled small-area estimates, not individual records. Crude prevalence shown above is the local rate as published; comparators are age-adjusted vs the Connecticut mean and the US mean — both population-weighted across counties — so geographies with different age structures stay apples-to-apples. Sources: CDC PLACES · 2025 release · BRFSS 2022-2023.
Sources.
- EPA Toxics Release Inventory · retrieved 2026-05-07.
- EPA Safe Drinking Water Information System · retrieved 2026-05-07.