Washington-Arlington-Alexandria, DC-VA-MD-WV
- High ozone days per year: 27
- No. of days with unhealthy particle pollution: 1
- People with asthma: 449,887
- Population: 6,216,710
In addition to being downwind of many Midwestern coal plants, the D.C. metro area is also notorious for high traffic volume, which contributes to higher ozone levels. In 2018, the Washington D.C. City Council passed a clean energy act to reduce emissions. The bill imposes a carbon tax on natural gas and fossil fuel based-electricity.
