According to the Texas Commission on Environmental Quality, from 2000 to 2016, the Houston-Galveston-Brazoria population increased by 44 percent, while ground-level ozone levels improved by 29 percent. Despite this progress, Houston is still not meeting EPA standards.
Stuart Mueller, operations manager for Harris County Pollution Control Services, said TCEQ released rules in the early 2000s regarding nitrogen oxides and organic compounds—which can be precursors to ozone formation—that contributed to the decline in ozone.
“We are getting this uptick in pollution—not anywhere near the levels that we saw 10, 15 years ago—but it isn’t on that same steady decline that we had been seeing,” said Stephanie Thomas, member of The Woodlands GREEN nonprofit and a Houston-based organizer and researcher for Public Citizen, a nonprofit political advocacy organization.
Houston-Galveston Area Council experts anticipate, under the EPA’s 2008 standards and based on previous years’ emissions, the EPA will reclassify Houston as “serious” this summer, meaning the region’s air quality has not improved enough to meet EPA standards.
“We have a ways to go [to improve air quality in Houston],” H-GAC Air Quality Manager Shelley Whitworth said.
Contributing factors
The Clean Air Act, a federal law passed in 1970 to control air quality, makes it a requirement for the EPA to issue standards known as the National Ambient Air Quality Standards for six criteria pollutants, according to the EPA’s website.
Experts have said two of the most critical to Houston are particulate matter and ground-level ozone. Different from stratospheric ozone—which is found naturally in the atmosphere—ground-level ozone is created from natural and man-made chemical compounds and pollutants, according to the TCEQ.
TCEQ Media Relations Specialist Andrew Keese said the TCEQ uses its network of ozone monitors across the Greater Houston area—including one at the WG Jones State Forest on FM 1488—to track emissions. While the city is meeting EPA standards with five of the six NAAQS, Houston has never met ozone standards.
Thomas said while Montgomery County does not have many of the emissions-producing companies found near the Port of Houston, chemical companies, freight ships and pollution from the southeast area still have adverse effects in the north.
“In The Woodlands, there’s really one air quality monitor at [WG] Jones State Forest, and it’s pretty interesting because there are days when the ozone readings at that monitor actually exceed some of the readings near the ship channel,” Thomas said. “I think that speaks to the behavior of ozone in our area.”
Another factor is increased traffic on roadways, said Alan Clark, director of transportation planning for H-GAC. The agency and the Texas Department of Transportation have worked to improve roadways in and around The Woodlands, alleviating congestion and, as a consequence, reducing gas emissions from vehicles, Clark said.
“When we adopt a new plan, when we fund new projects—particularly those that are of significant regional impact—we have to perform an explicit air quality analysis, using the TCEQ’s process for measuring emission impacts to show, to demonstrate, that we will continue to be on track to meet the emissions reductions required in that [plan],” he said.
Emissions effects
Despite progress toward cleaner air, Houston has never reached attainment—the acceptable standard—for ground-level ozone, according to the TCEQ.
The EPA measures ozone in terms of parts per billion, and after changing acceptable standards from 75 ppb to 70 ppb in 2015, a nonattainment area has levels exceeding 70 ppb. This is measured by the 8-hour design standard, or the annual fourth-highest daily maximum 8-hour ozone concentration averaged over three consecutive years.
Data collected from 2013 to 2015 measures ozone levels in Harris and Montgomery counties at 79 ppb and 73 ppb respectively, according to a 2016 TCEQ report submitted to the EPA. Neither meet ozone standards.
“Having higher than the standard levels of ozone can actually be harmful to our health,” Thomas said. “Ozone creates a number of respiratory issues, and children are especially vulnerable as well as the elderly and people who have pre-existing conditions.”
Ozone is not the only air quality concern. According to the American Lung Association, the Houston-The Woodlands area ranked 16 out of 184 metropolitan areas nationwide for particle pollution, which involves particles from exhaust emissions, which can affect the heart and lungs and cause serious health effects.
Harris County’s average daily density of fine particulate matter is the highest of any Texas county, while Montgomery County has the third-highest, according to data from the Robert Wood Johnson Foundation.
Economic consequences
In addition to physical effects, environmental experts agree Houston’s inability to meet EPA standards can also be bad for the health of the economy. As the EPA is working to update its requirements, researchers and companies have to prepare for the newer regulations.
For areas not in compliance with EPA standards—such as Houston—the TCEQ develops a state implementation plan, a plan submitted to the EPA for approval that includes a collection of regulations used by local districts to reduce air pollution.
“That can put limitations on business—it can impact us in terms of the projects that can happen in the region,” she said. “Being in nonattainment of ozone has different negative consequences for our region, from our health to our economy.”
Mustapha Beydoun, vice president and chief operating officer of the Houston Advanced Research Center, a Woodlands-based research organization that focuses on sustainability programs for air quality, energy and water, said environmental factors can work against Houston when competing against other cities.
Beydoun said the Greater Houston area has to compete for large companies like Amazon. When the retail giant announced in 2017 it was looking for a location for a second headquarters, more than 200 cities applied. While Houston submitted a proposal, it was not selected, unlike other Texas cities, Austin and Dallas, which were in the top 20 finalists.
“If you look at what happened with the whole Amazon headquarters thing—look at the criteria they looked at,” Beydoun said. “It’s not just space and financing. It had a lot of environmental criteria. Air quality is an important aspect of that.”
Air pollution solutions
While Beydoun said Houston’s ozone levels have dropped from highs of 230-250 ppb in the late ’90s, there is still work to be done to identify problem areas. To this end, HARC has begun using a mobile lab to measure air quality in previously unmonitored areas.
“One of the problems we have is Houston is one of the most monitored cities in the country, but there’s a big gap with what’s happening between the monitors,” he said. “We’re hoping to be able to look at emissions and air quality along transportation corridors and see what does air quality look like on your commute?”
However, the Greater Houston area, as a whole, still has obstacles to overcome. Considering the progress the city has made, Whitworth said Houston’s inability to meet the standard for ozone proves other solutions need to be looked at.
Thomas said TCEQ has a number of programs that could help reduce vehicle emissions, including the Texas Emissions Reduction Plan. The program helps companies and government agencies apply for funding for cleaner vehicles.
“If you are driving a truck that is 20 years old, you are going to be contributing significantly more air pollution than a truck that is a year old,” she said.
In addition to proposed solutions and the implementation of EPA and TCEQ rules, Whitworth said residents can help reduce emissions by carpooling.
“We are a major metropolitan area, [and] we are developing [a] more suburban system,” she said. “We need folks to learn to change their way of thinking.”
Additional resources:
The Woodlands GREEN: The Woodlands Grass Roots Environmental Education Network is a nonprofit organization dedicated to conservation, recycling, waste reduction and air and water quality.
One Breath Partnership: An advocacy group dedicated to educating residents about air quality in Houston and advancing policy to reduce pollution.
Texas Environmental Research Consortium: While funding for this group has ended, residents can use this site to see projects from 2002-2009 that studied contributions to the area's overall pollution and worked with state agencies, like the TCEQ, to identify emissions-reducing measures needed for Texas' State Implementation Plan.
