BoCo Alert System

Boulder County non-emergency offices will be closed on Monday, May 29 for Memorial Day.

Denver's brown cloud


Today’s Ozone Action Alert Status

Unlike the good, protective ozone layer in the upper stratosphere, ground-level ozone is a harmful air pollutant that affects all of us. It’s formed when emissions from everyday activities like:

  • Fueling
  • Painting
  • Solvent use
  • Driving
  • Lawn mowing
  • Industrial emissions

When combined, these pollutants “cook” in the heat from sunlight to form ozone.

Ozone continues to be a serious health issue and air pollution concern in Boulder County, and the nine-county Denver region. Currently five monitors along the Denver Metro Area/North Front Range indicate ozone levels that significantly exceed the new ozone standard, including the monitor in south Boulder.

Learn More

Contact Us

Air Quality Program

Main: 303-441-1564
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