SmogRank / Countries / United States / Maine

Most polluted cities in Maine, United States

4 measured cities ranked by PM2.5, last 7 days. Worst: Augusta at 3.4 µg/m³, #2168 in the world.

#City µg/m³
1Augusta Maine
3.4
2Portland Maine
3.3
3Lewiston Maine
3.2
4Bangor Maine
3.1
Good 0–9.0Moderate 9.1+Unhealthy for sensitive groups 35.5+Unhealthy 55.5+Very unhealthy 125.5+Hazardous 225.5+No data

Estimated: cities without a monitor

Maine cities we can't measure, with model estimates for the last 7 days. Listed by population, not ranked: estimates aren't precise enough to rank. Model estimates from the Copernicus Atmosphere Monitoring Service (CAMS), adjusted to measured cities nearby where there are any. Adjusted, a single day lands within ×1.5 of what a monitor would read about two times in three; unadjusted, it can be off by half or double. Treat them as a guide, not a measurement.

City7-day estimateBand
West Scarborough estimated≈ 3 µg/m³Good
South Portland estimated≈ 3 µg/m³Good
South Portland Gardens estimated≈ 3 µg/m³Good
Auburn estimated≈ 3 µg/m³Good
Biddeford estimated≈ 3 µg/m³Good
Sanford estimated≈ 2 µg/m³Good
Saco estimated≈ 3 µg/m³Good
Westbrook estimated≈ 3 µg/m³Good
Waterville estimated≈ 2 µg/m³Good
Brunswick estimated≈ 2 µg/m³Good

Updated 2026-10-01 11:07 UTC. Values are PM2.5 in µg/m³ (fine particles), the median of each city's monitors.