Given the number of times Dr. Jeffrey Jarvis saw highway signs blaring “OZONE ALERT” this summer, they may as well have been broken, he said.

For Jarvis and his team of first responders at EMS provider MedStar, poor air quality days mean more calls for respiratory emergencies as people with underlying conditions, including asthma, become more likely to require hospitalization. Conducting an analysis of calls was difficult this year.

“It’s getting really hard to make this analysis because you need something to compare it to,” Jarvis, MedStar’s medical director, said. “There just aren’t many days anymore that aren’t ozone alerts, so it seems like it’s getting harder and harder to find a comparison group.”

Jarvis’ point is backed by data. A boiling hot summer was the backdrop for one of the worst air quality seasons North Texas has seen since 2012, matched only by equally poor ozone levels in 2022.

The North Central Texas Council of Governments counted 48 days between May and September where the region’s air quality reached levels of ozone considered unhealthy by the Environmental Protection Agency. The council of governments is tasked with helping local governments meet federal air quality standards.

What is ground-level ozone, also known as smog?

“Ozone forms when emissions from transportation, industrial and commercial operations, and natural sources such as vegetation emit nitrogen oxides and/or volatile organic compounds. These pollutants react in the presence of sunlight and heat to create ground-level ozone.” – North Central Texas Council of Governments

Clinical studies have linked exposure to ozone, or ground-level smog, with reduced lung function and higher frequency of asthma episodes, among other health effects. In August, just over half of the month consisted of warnings to avoid significant time outdoors because of ozone conditions. 

“It has been grueling,” Jenny Narvaez, air quality program manager for the council of governments, said. “It’s not just our area that’s suffering from this. I mean, the whole state is high in terms of ozone readings this summer.” 

Narvaez and the Texas Commission on Environmental Quality, the agency tasked with developing strategies to improve air quality, are still working to understand the reasons behind the uptick in ozone alert days. Extended periods of extreme heat certainly contribute to the problem, she said. 

“We’re just, like, the perfect nesting ground for ozone formation,” Narvaez said. “With low wind, ozone tends to form and then it’ll stay instead of being blown off by the wind. A lot of our summers are not very windy days, and humidity tends to drive it as well.”

Without improvement, region faces $45M in annual fines

The region recorded its lowest number of alerts in 2016, but the count has increased over the past decade, according to a September report by Chris Klaus, senior air quality management program manager for the council of governments.

That trend has consequences, both in the form of health concerns and annual fines imposed by the EPA. 

Penalties for not meeting the Clean Air Act standards mostly consist of stricter pollution controls and revising implementation plans overseen by state agencies. However, a region that is classified as a “severe” violator can impose financial penalties of $5,000 per ton on major pollution sources if they do not meet required ozone reductions.

Last year, North Texas became a “severe” violator of the EPA’s 2008 ozone standard requiring metro areas to average at or below 75 parts per billion of ozone. The clock to avoid imposing $45 million in annual fines on businesses begins ticking in 2024 and wraps at the end of 2026, Narvaez said. 

Based on ozone data between 2021 and 2023, the EPA is expected to reclassify Dallas-Fort Worth as a “serious” violator of its 2015 Clean Air Act standards, a downgrade from “moderate.” To determine if a region has violated ozone standards, the EPA averages the fourth-worst ozone pollution days over a period of three years.

Preliminary data shows that the region averaged 81 parts per billion of ozone over the most recent three-year period — well above the federal requirement of 70 or lower parts per billion. 

“We took a huge step backward,” Jim Schermbeck, longtime director of North Texas environmental activism group Downwinders at Risk, said. “If this is the new normal, it just got much harder to have cleaner air.” 

An autonomous truck leads a convoy down the North Tarrant Expressway in far north Fort Worth on June 20, 2023. According to 2020 data from the North Central Texas Council of Governments, 67% of nitrogen oxide emissions come from transportation. (Matthew Sgroi | Fort Worth Report)

What’s behind the uptick in ozone days? It’s still not clear to experts

With the threat of stricter pollution controls and annual fees on the horizon, state environmental staff are required to submit revisions to their Clean Air Act implementation plan by May 2024.

“Even though that is starting next summer, we are right now working with the state trying to come up with strategies to ensure or help them to determine what we can do in preparation for that,” Narvaez said. 

During the past two decades, North Texas officials have focused their efforts on reducing nitrogen oxide emissions commonly associated with cars. Their initiatives include retiring vehicles and equipment with heavy-duty diesel engines; reducing traffic congestion and idling; providing funding for alternative fuel vehicles; and leading public campaigns to take fewer car trips and operate vehicles in ways that reduce emissions.

Thanks to these strategies, Klaus and his colleagues say they’ve seen immense progress on air quality since 1990, when the region lingered in the 125-130 range for ozone parts per billion. But that progress appears to have hit a ceiling, and experts are struggling to understand why. 

One obstacle in the council of governments’ path is modeling from the Texas Commission on Environmental Quality, which Klaus says systematically predicts fewer ozone alert days than actually occur in Dallas-Fort Worth. This was especially clear during the early days of the COVID-19 pandemic, when vehicle traffic dropped by 20% and smog levels in North Texas did not drop as air quality models expected, Klaus previously told the Report

“It is significantly off from real-world observances, and we believe further evaluation is needed,” Klaus wrote in a July letter to the environmental commission requesting more meetings and engagement with staff members.

Chris Klaus, senior air quality management program manager for the North Central Texas Council of Governments, speaks to staff members representing Dallas-Fort Worth cities during a Jan. 27, 2023, meeting. Klaus and his colleagues will work with state officials on strategies to reduce ozone levels. (Haley Samsel | Fort Worth Report)

Regional experts are also asking if they need to shift their focus to the other half of the ozone equation: volatile organic compounds. 

Most of those compounds come from plant and wildlife sources, including forest fires. But about one-fourth come from man-made activities, including petroleum and natural gas extraction, burning of fossil fuels, transportation and industrial plants that manufacture products like paints, lubricants and adhesives.

The council of governments is wrestling with the idea that it has focused all its attention on reducing one source of emissions without addressing other key pollution sources, said Schermbeck, the environmental activist. 

“They’ve focused on cars, cars, cars. They’ve done all that, and the smog levels have not gone down,” Schermbeck said.

The unanswered questions are why volatile organic compound levels have gone up and which ones are the culprits, Schermbeck said.

“Ten years ago they thought they had it all figured out,” he said, “and now they’re questioning where the DFW smog problem comes from.” 

Victoria Cann, a spokesperson for the Texas Commission on Environmental Quality, said the agency has initiated extensive outreach efforts over the past year to address all of Texas’ ozone nonattainment areas, including Dallas-Fort Worth. The agency’s models use the latest data and EPA guidance to model ozone outcomes, she wrote by email. 

As part of its revisions to the state plan, the agency also reviews its air quality modeling, Cann added. Future meetings will be scheduled to provide North Texas officials with information on new technical developments, she said. 

The state’s ultimate goal is to bring the region into compliance with Clean Air Act regulations and avoid issuing fines — known as Section 185 fees — to polluters, Cann said. Formal rules for the fees aren’t due to the EPA until late 2025, but the state will begin hosting meetings with a stakeholder group this fall, she added. 

A natural gas drilling rig operates near AT&T Stadium in Arlington on Jan. 12, 2023. Natural gas operations generate volatile organic compounds, which contribute to ground-level ozone or smog. (Cristian ArguetaSoto | Fort Worth Report)

Summer hasn’t ‘erased progress,’ but critics want more EPA involvement

In Schermbeck’s eyes, the Texas Commission on Environmental Quality should not be in charge of strategies to reduce ozone pollution. State officials find ways to exploit Clean Air Act deadlines to give them more time or wait until a new presidential administration arrives and becomes less strict with air quality enforcement, Schermbeck added. 

The EPA should take over the state’s role and enforce rules that would lead to long-term improvements, Schermbeck said. Earlier this month, the federal agency rejected ozone reduction proposals the state submitted in 2020 and indicated EPA officials would intervene if Texas didn’t take further action to reduce ozone levels in Dallas and Houston. 

“I’m not sure the Clean Air Act anticipated bad faith actors at the state level as bad as Texas has been,” Schermbeck said. “They shouldn’t have any enforcement authority at all. They are not serious people when it comes to this. Anything short of breaking that cycle is woefully insufficient.” 

Narvaez, air quality program manager for the council of governments, sees reason for hope in the coordinated effort between state and local governments to improve air quality. 

EPA Region 6 Administrator Earthea Nance, right, speaks with members of Midlothian Breathe, an air quality advocacy group, at Kimmel Park on March 16, 2023. Nance visited Midlothian and Arlington to learn more about residents’ experience with industrial air pollution. (Haley Samsel | Fort Worth Report)

Her organization is also leading a regional climate planning effort, funded by an EPA grant, that will identify air quality projects across North Texas. Once the plan is adopted, local governments will become eligible for further federal funding to make their projects a reality, she said. 

Regional leaders can’t do anything about the weather conditions that create ozone and bring pollution from other regions to Dallas-Fort Worth, Narvaez said. But she and her staff want to better understand where emissions are coming from and how they can be controlled. 

“This summer has not erased progress. We are still working. We’re still progressing,” she said. “That’s why they average it over three years, because some summers are bad and some summers are not that bad.” 

In the meantime, Jarvis and his MedStar colleagues urge residents to stay aware of ozone alerts and how they could affect their health. The burden of poor air quality is often not evenly distributed, Jarvis said, and children in lower socioeconomic groups often bear the brunt of respiratory diseases. 

“The challenge is we don’t get to control the amount of ozone. These aren’t things we can easily manipulate,” he said. “So what do you do when you’re in a situation where the ozone is just always high? It’s going to have some pretty significant effects.” 

Haley Samsel is the environmental reporter for the Fort Worth Report. You can reach them at

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Haley Samsel is the environmental reporter for the Fort Worth Report. You can reach them at Her coverage is made possible by a grant from the Marilyn Brachman Hoffman...