SGV Air Quality
The San Gabriel Valley consistently ranks among the most polluted air basins in the United States. Trapped between the San Gabriel Mountains and prevailing westerly winds, the SGV accumulates ozone, PM2.5, diesel exhaust, and wildfire smoke at levels that disproportionately burden low-income communities of color.
The SGV is in a non-attainment zone for both ozone and PM2.5.
Despite decades of improvement, the South Coast Air Basin — including the SGV — still violates federal health standards for ground-level ozone and fine particles. CalEnviroScreen ranks many SGV communities in the top 10% of cumulative pollution burden statewide. This is an environmental justice issue.
#1
Worst Ozone in US
3×
Federal PM2.5 Limit Exceeded
Top 10%
CalEnviroScreen Burden
3
Major Freeway Corridors
Air Pollutants of Concern in the SGV
These pollutants are detected at elevated levels in the SGV and pose documented health risks to residents. Data sourced from EPA, SCAQMD, CalEnviroScreen, and peer-reviewed research.