Air Qualityi
Water Systemsi
Water Violationsi
6Active NPDESi
Air Quality — Sangamon 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
142Ozone Daysi
131Drinking Wateri
SDWISPublic water systems registered to serve this area. Community systems (CWS) provide water to residents year-round. Transient systems serve places like gas stations or restaurants. Violations indicate a system failed to meet federal drinking water standards.
Community Systemsi
2Active Systemsi
4Recent Violationsi
6Recent Violations (Last 5 Years)
ROCHESTER
Historical Violations (Over 5 Years Ago)
SOUTH SANGAMON WATER COMMISSION
Wastewater & Stormwater Permits (NPDES)i
NPDESUnder the Clean Water Act, any facility that discharges wastewater or stormwater into rivers, lakes, or streams must hold an NPDES permit. "Effective" means the permit is currently active and the facility is authorized to discharge under its permit conditions.
Active Permitsi
5Expired / Terminatedi
8Cleanup Sites (Brownfields)i
EPA BrownfieldsFormer industrial or commercial properties where contamination has been found. "Remedy Complete" means cleanup is finished. "Construction Complete" means cleanup infrastructure is built but monitoring continues. "In Progress" means the site is still being investigated or cleaned up.
Leaking Underground Storage Tanksi
IL EPAUnderground storage tanks (commonly at gas stations) can leak fuel and chemicals into soil and groundwater. "Open" means the leak is still being investigated or cleaned up. "Closed" means the site received a No Further Remediation (NFR) letter — cleanup is done.
Open Incidents (3)