A new report from the American Lung Association finds that metropolitan Denver in 2020 had improved ozone levels over the previous three years but remained the 8th most ozone-polluted metro area in the United States, tied with Salt Lake City. Fort Collins ranked 17th.
The seven metro areas most polluted by ozone were all in California with the exception of one in Arizona.
No Colorado city, however, cracked the top-25 list in either shorter-term or year-round particle pollution.
In New Mexico, Las Cruces and neighboring El Paso ranked 13th for ozone.
By a different metric, that of counties, Colorado also looks poorly in the ozone rankings, as Jefferson County ranks 12th worst in the nation and Douglas County 22nd. New Mexico has two counties in the top 25: Doña Ana (Las Cruces at 28th and Eddy at 24th). The latter is the center of oil-and-gas drilling operations in New Mexico’s part of the Permian Basin.