Exceptionally clean air is hard to come by in the US. Between emissions from power plants, cars, and trucks; oil and gas drilling; wildfires; and agricultural pollution, most major American cities have their share of days when their air is polluted at unhealthy levels. Some have it much worse than others.
But in its State of the Air report released Tuesday (April 19), the American Lung Association identified a selection of cities that did not log a single bad-air day at all between 2013 and 2015, the time period analyzed. A bad-air day is defined by a spike in either particulate matter pollution (also known as PM2.5) or ozone pollution above the limit set by the US Environmental Protection Agency for acceptably healthy air. Both ozone and particulate pollution are linked to respiratory diseases, developmental delays, and a litany of other health risks.
In the following six cities, residents never experienced a day when ozone or particle pollution spiked into unhealthy ranges, and average year-round particulate pollution in these cities ranked among the lowest nationally. In alphabetical order, these are the cleanest metropolitan areas in America:
- Burlington-South Burlington, Vermont (pop. 217,042)
- Cape Coral-Fort Myers-Naples, Florida (1,059,287)
- Elmira-Corning, New York (184,702)
- Honolulu, Hawaii (998,714)
- Palm Bay-Melbourne-Titusville, Florida (588,088)
- Wilmington, North Carolina (277,969)
Most of these are relatively small cities. But it’s not necessarily true that a smaller population means cleaner air—many of the worst-performing cities in the report had small populations. For example, Fairbanks, Alaska, with a modest population of just under 100,000, ranks fifth in the list of cities with the most severe problem of unhealthy spikes in particulate matter pollution—largely due to the widespread use of wood-burning stoves to heat homes in the winter.
Though not quite as clean as those six cities, 11 other cities had notable successes: They had no days of unhealthy spikes in particulate matter, and also had among the lowest average particulate matter in the air year-round. They did experience days of unhealthy ozone. Still, here are what we might dub the “pretty clean” cities in America (also in alphabetical order):
- Bangor, Maine
- Casper, Wyoming
- Colorado Springs, Colorado
- Farmington, New Mexico
- Homosassa Springs, Florida
- Lakeland Winter Haven, Florida
- North Port Sarasota, Florida
- Orlando-Deltona-Daytona Beach, Florida
- Pueblo Cañon City, Colorado
- Sierra Vista-Douglas, Arizona
- Syracuse-Auburn, New York
While the above criteria couldn’t be traditionally “ranked,” since they all represented a total lack of unhealthy days, we can rank cities according to lowest average year-round particulate matter pollution. Under the Clean Air Act, the EPA set a health standard for particulate matter: Any city with a concentration higher than 12 micrograms per cubic meter (μg/m3) of PM2.5 is exposing their residents to health risks and fails to comply with the Clean Air Act. The following cities logged the lowest year-round PM2.5 averages, all well below the 12 μg/m3 standard: