Assessing Air Quality Conditions in the St. Louis Region as the 2022 Forecasting Season Wraps Up

Air quality forecasting concluded at the end of last month, and the Clean Air Partnership is pleased to report that, as we reflect on this season, ozone air pollution levels remained consistent with those of the prior year. The 2022 forecasting season began with encouraging news that the St. Louis region had once again escaped being ranked among the top 25 most-polluted cities, though we still struggle with unfavorable air quality, as St. Louis ranked 37 in the nation overall for most ozone-polluted U.S. cities and recently failed to meet the U.S. Environmental Protection Agency’s (EPA) latest ozone standards.

However, a look back over the past several months reveals that our air quality remained relatively healthy during the peak ozone season. From the beginning of May through Sept. 30, green was the dominant color with 80 days where the air quality was good, followed by 69 yellow or moderate air quality days, and four unhealthy orange days for sensitive populations, including children, older adults, people who work or exercise outdoors, and those with existing lung disease or cardiovascular disease.  The data also revealed no poor or red air quality days occurred.

This year, the Clean Air Partnership worked collaboratively with Citizens for Modern Transit (CMT) and other partnering organizations to inform people the way they choose to travel impacts the quality of air area residents breathe, while motivating them to modify commuting behaviors as often as they are able during the summerlong “Don’t Pollute. Switch Up Your Commute,” campaign. Hundreds of St. Louisans signed up to receive daily air quality forecasts to stay informed about ozone pollution levels in the region and how those levels can affect their health, and even though the forecasting season has come to an end, area residents can still visit to access a wealth of information on the wide array of alternative transportation options available on both sides of the Mississippi River, associated schedules, pricing, programs, ride matching services and incentives.

Additionally, there are many other eco-friendly lifestyle changes unrelated to commuting that individuals, businesses and municipalities can consider any time of year to positively impact air quality and improve lung health in their communities. These changes include efforts to conserve energy, recycle, reduce waste and reuse items, all of which can be found and more at

Air quality forecasting will resume in May 2023. In the meantime, individuals can get a head start by signing up here to receive the daily forecast in their email inboxes or via text message from the EPA’s AirNow EnviroFlash air quality alert system. We thank you for your continued efforts to help keep our air quality in healthy ranges and look forward to re-engaging with you next year!

Latest EPA report reveals more work to be done to meet ozone standards in the St. Louis area

According to a new report released by the U.S. Environmental Protection Agency (EPA), the St. Louis metropolitan area has failed to meet the agency’s most recent ozone standards as ozone levels remain too high. The report moves St. Louis City, St. Louis County, St. Charles County, Jefferson County and parts of Franklin County from the marginal to moderate ozone level category, with more than 20 other regions across the country also labeled under moderate ozone classifications.

As a result, the region will need to adopt the standards designated back in 2015 that set the ozone limit to 70 parts per billion in effort to preserve human health and the environment by the new attainment date of August 3, 2024. Since the latest data showed ozone levels in the St. Louis area at 71 parts per billion, the new regulations issued under the EPA’s reclassification for the region will help protect area residents while limiting the influence of the industries that are a leading source of air pollution.

The shift is due to an increase in ground-level ozone in the area, which arises when emissions from vehicles, power plants and other sources react with sunlight. This puts vulnerable populations – including children and teens, anyone 65 and older, people who work or exercise outdoors, and those with existing lung disease or cardiovascular disease – more at risk from long-term exposure to the gas at ground level that can lead to asthma and other respiratory illnesses. Additionally, the EPA’s report corresponds with findings from the American Lung Association’s 2022 “State of the Air” report, which graded St. Louis City, St. Louis County and St. Charles County with F’s for having recorded higher ozone levels during the years covered by the report (2018-2020).

With that in mind, the Clean Air Partnership encourages St. Louisans to continue their efforts to take voluntary steps to reduce emissions, as those actions play a critical role in improving air quality conditions and enhancing lung health in the region. One way individuals can show they care about clean air is by utilizing alternative modes of transportation, including transit, carpooling, vanpooling, walking, biking or telecommuting as often as they are able to help improve outcomes. Businesses and municipalities can also work collectively to reduce their environmental impact by introducing paperless policies, implementing a fully remote or hybrid schedule for employees to cut back on commuter emissions, installing electric vehicle charging stations or bike racks in parking structures to promote sustainable modes of transportation and more.

Changes at any level can help contribute to a greener and cleaner environment. Together, we can take small steps forward to bring the region into attainment and keep the air quality in healthier ranges. Additional air quality information and other tips to help clear the air can be accessed by visiting the Clean Air Partnership’s website, liking the Clean Air Partnership on Facebook or by following the organization on Twitter @gatewaycleanair. To access the full EPA report, visit

MoDOT Paving the Way for Cleaner Air in the St. Louis Region

With a long-standing commitment to help improve air quality in the St. Louis metropolitan area, the Missouri Department of Transportation (MoDOT) recognizes that ozone pollution is not only extremely unhealthy for residents, but also hurts the economic viability of our region and can even threaten federal highway funding in the state. Since idling vehicles and their related emissions are one of the leading sources of air pollution, MoDOT values the importance of keeping area roadways cleared 24/7 and offers up information about possible congested areas to help reduce air pollution and keep the region’s air quality in healthy ranges.

For starters, MoDOT has eight solar-powered portable message boards along high-traffic interstates and highways that display the daily ozone forecast during the air quality forecasting season and are also used for traveler information in times of major incidents on the highways to help alleviate congestion. Over half a million motorists daily have the opportunity to view these messages and stay informed about ozone pollution levels in the region, so they can plan to modify their commute for the following day. In addition to their smaller portable message boards providing daily air quality information, MoDOT uses its large stationary message boards on red ozone days, as well as places a warning message on its real-time traffic information website. With these three components being used for traveler information, MoDOT has the potential to reach more than a million motorists during critical ozone alerts.

To help further reduce environmental impact, MoDOT’s Gateway Guide program strives to better manage the growing amount of traffic on state-maintained roadways. The Gateway Guide team works around the clock and uses many state-of-the-art devices that, when combined, serve as powerful tools to relieve traffic congestion and improve safety. The program uses real-time traffic information to help reduce traffic delays caused by incidents, work zones and the rising number of vehicles on the highways. By monitoring the roadways, the team can direct the appropriate emergency response forces to those incidents – including departmental emergency operations to clear minor incidents or to direct traffic around major ones. The team also provides this information in several formats for drivers – primarily by social media, text or overhead message signs. Moreover, MoDOT carries out a yearly traffic signal optimization program on arterial corridors, updating timing plans and coordination across designated corridors, which reduces emissions by decreasing travel times and reducing stops and delays on state routes.

Additionally, MoDOT recently entered into a partnership with WAZE as part of the Connected Citizen Program (CCP), which brings cities and citizens together by allowing users to alert fellow motorists of crashes, construction, road hazards or road closures they may not be anticipating. In turn, this enables MoDOT and other government partners to respond more efficiently to accidents and congestion, resulting in one of the most succinct, thorough overviews of current road conditions today.

Beyond these various initiatives that help motorists to do their part for cleaner air, on days when air quality is forecasted to approach unhealthy levels, MoDOT changes its own internal operations so as not to cause excess ozone-causing emissions. A main component involves reducing maintenance operations that may cause traffic congestion, except for safety reasons, on forecasted red ozone days. The organization also engages its employees in the regional clean air effort, sharing the daily air quality forecast with them and encouraging use of alternative modes, such as carpooling, during the ozone season.

For more information on MoDOT’s available resources and their clean air connection, visit And be on the lookout for a future article highlighting the Illinois Department of Transportation’s (IDOT) initiatives to help clear the air.  To learn more about the link between sustainability and air quality, explore the Clean Air Partnership’s website, like us on Facebook or follow us on Twitter at @gatewaycleanair.