Air Quality
Good
Water Violations
1
Active Contamination
21
Active Permits
8
Air quality in Boulder County is rated good with a median AQI of 50 (273 days measured in 2025). 4 community water systems serve the area, with 1 recent violation in the last 5 years. 34 industrial facilities report toxic chemical releases totaling 73.3K lbs. 21 contamination sites are tracked, all with completed or ongoing remediation.
Air Quality — Boulder County (2025)i
AQSThe Air Quality Index measures how clean or polluted the air is on a given day. AQI is reported at the county level. A score of 0-50 is considered good; 51-100 is moderate; above 100 may be unhealthy for sensitive groups.
Median AQI
PM2.5 Daysi
70Ozone Daysi
202Drinking Wateri
SDWISPublic water systems registered to serve this area. Community systems (CWS) provide water to residents year-round. Violations indicate a system failed to meet federal drinking water standards.
Community Systemsi
4Active Systemsi
2Recent Violationsi
1Recent Violations (Last 5 Years)
LONGMONT CITY OF
Industrial Monitoringi
Toxic Release Inventory (TRI)i
TRIContamination Sitesi
Contaminated sites tracked by the EPA and state agencies. Superfund sites are the most seriously contaminated locations. Brownfields are former industrial properties being cleaned up for reuse. LUST sites have confirmed leaks from underground storage tanks.