Air Quality ‘Looking’ Much Better In The Knoxville Region

Your eyes aren’t deceiving you – the Smoky Mountains can be seen more clearly and more often thanks to recent air quality improvements.

July 2004

July 2016

A picture is worth a thousand words. Images from the Look Rock Observation Tower compare conditions in the months of July 2004 and 2016. Daily ozone levels peak during summer months, causing hazy and smoggy conditions. Thanks to successful efforts to reduce airborne pollutants, improved clarity of the atmosphere between these periods is striking and shows dramatic effect on visibility on an every-day basis.  Source: National Park Service

Major improvements to air quality over the last several years mean that the East Tennessee region is now meeting all Environmental Protection Agency (EPA) standards. And that’s very important for the health of both our residents and our economy.

Over the last several decades, the Knoxville region has been out of compliance with EPA standards for two pollutants – ozone and particulate matter – and was officially designated a ‘non-attainment area.’ That designation carried a heavy cost: it meant the air was sometimes unhealthy to breathe and it kicked in federal restrictions on some types of new business recruitment, detrimental to the regional economy.

Most air pollution is from man-made sources, especially transportation (vehicle tailpipe and fuel evaporation emissions) and industry (manufacturing and power generation involving combustion). Investments by power generators, such as TVA, and technological improvements to vehicle fleets have resulted in pollutant reduction.

Results of our efforts to comply with Clean Air Act standards can be seen in some pretty impressive stats: in 1999, we exceeded ozone limits (70 parts per billion) on more than 120 days. In 2017, that number dropped to just one day.

This chart shows the number of days each year since 1997 that monitoring equipment in the Knoxville region recorded pollution that exceeded the federal eight-hour ozone standard. Source:  Air Data. EPA

While EPA attainment status is critically important in ensuring clean air to breathe, increased visibility has another big benefit to many people. Our region relies on its natural beauty and views, both of and from the Great Smoky Mountains National Park, for our own enjoyment as well as for the major economic impact as a driver of tourism.

Average visibility distances from the Smokies have been gauged since 1990. Tremendous and sustained improvement has been measured since 2007 — on a typical day, Mount LeConte is now visible from many parts of the region.


Dramatic increases in visibility, particularly in the last 10 years, mean that the Smoky Mountains are again visible from downtown Knoxville, 35 miles away.  Source: Interagency Monitoring of Protected Environments

Others have taken notice of our improved air quality, evidenced by a recent article published by the American Lung Association. They spotlight the success of Knoxville in cleaning up its air and offer details about the process that made such significant progress possible.

Realtime Visibility and Pollutant Conditions from Look Rock