Air Quality
Moderate
Water Violations
11
Active Contamination
18
Active Permits
13
Air quality in Weld County is rated moderate with a median AQI of 52 (274 days measured in 2025). 4 community water systems serve the area, with 11 recent violations in the last 5 years. 18 contamination sites are tracked, all with completed or ongoing remediation.
Air Quality — Weld 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
78Ozone Daysi
194Drinking 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
3Recent Violationsi
11Recent Violations (Last 5 Years)
EVANS CITY OF
Historical Violations (Over 5 Years Ago)
ARRIBA TOWN OF
Industrial Monitoringi
Contamination 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.