Understanding Utah’s Air Quality: The Impact of Ozone Pollution

Understanding Utah’s Air Quality: The Impact of Ozone Pollution

Learn about ozone pollution and how you can take action. 

Summer v.s Winter pollution

Did you know that Utah’s air quality is affected by pollution in both summer and winter? During the winter, air quality in the northern valleys, including Salt Lake City, is among the worst in the nation due to a combination of geography and emissions from human activities. The air is so bad that we can see it. However, in the summer, we face a different type of pollution—ozone pollution, which is invisible but just as harmful to our health.

image of utah mountains in the summer in contrass to winter.

What is Ozone?

Ozone is a gas made up of three oxygen molecules. While “good ozone” in the stratosphere protects us from the sun’s harmful UV radiation, “bad ozone,” or ground-level ozone, is a major concern, primarily during summer. This type of pollution is created when “ozone precursors” like nitrogen oxides (NOx) and volatile organic compounds (VOCs) build up throughout the day and react in the presence of heat and sunshine, forming ozone. Major sources of these precursor emissions in Utah include transportation, industrial facilities, and oil and gas production. Once ozone is created, it can travel across regions and states, affecting people far from the original pollutant sources.


Exposure to ozone pollution has been described as feeling like getting a sunburn on your lungs. It can damage our lungs and cardiovascular systems, as well as other organ systems.

Climate change is making this problem worse

Due to climate change, Utah is experiencing hotter and drier summers, which means more ground-level ozone. Here at HEAL Utah, we want to help you stay informed and safe, so you can take action to protect yourself and your community.

Gif source: New York Times 

Health effects of ozone pollution

Exposure to ozone pollution has been described as feeling like getting a sunburn on your lungs. It can damage our lungs and cardiovascular systems, as well as other organ systems. Vulnerable groups, such as children, the elderly, pregnant individuals, those with pre-existing lung conditions like asthma, and people who engage in outdoor physical activities, are particularly at risk. Common adverse effects include:

Difficulty breathing



Aggravated Asthma Symptoms

Chest discomfort

Lung inflammation

Long-term exposure to ozone has been linked to chronic respiratory issues and an increased risk of respiratory infections. Studies have also shown linkages between ozone exposure and nervous system, reproductive, and developmental harms. Even lower ozone levels can impact sensitive populations.

Where does Utah rank?

In November 2022, the Environmental Protection Agency (EPA) reclassified the Northern Wasatch Front area, which includes Salt Lake and Davis counties, as well as parts of Tooele and Weber counties, from “marginal” to “moderate” nonattainment. This change reflects a worsening of the eight-hour average ozone levels, which have increased from 0.071-0.080 parts per million to 0.081-0.093 parts per million.


To put this in perspective, a recent report from the American Lung Association ranked the Salt Lake City-Provo-Orem zone as the 9th worst for high ozone days out of 228 metropolitan areas.

Image of the United States map with Utah being highlighted. To the right is an image showing where Utah, Salt Lake, Weber, Davis and Tooele county are and how they are in non-attainment.

Utah’s back-and-forth fight on Ozone pollution

In March 2023, the EPA introduced its latest “good neighbor” rule to significantly reduce smog-forming nitrogen oxide pollution from power plants and industrial facilities in 24 states, including Utah. This rule, also known as the Cross-State Air Pollution Rule (CSAPR), aims to help states meet air quality standards by holding out-of-state pollution sources accountable.


Under this rule, Utah and other states must submit plans to reduce emissions from fossil fuel-fired plants and industrial facilities contributing to poor air quality in neighboring states. If a state fails to submit an adequate plan, the federal government will step in to ensure compliance. The rule is expected to cut nitrogen oxide pollution from power plants by 50% over the next four years (EPA, 2023).


However, Rocky Mountain Power and the state of Utah are fighting against this rule through a costly legal campaign. Rocky Mountain Power operates two coal-fired power plants in Utah, Hunter and Huntington, which lack pollution controls to reduce ozone pollution. During the 2023 legislative session, Utah lawmakers allocated $2 million in taxpayer dollars to challenge the EPA’s new rule. In 2024, Utah passed a constitutional sovereignty act to opt out of federal regulations like the Clean Air Act, which they consider an overreach. The CSAPR is currently under review by the US Supreme Court. If the Court rules against the EPA, we could lose a critical tool for improving air quality nationwide.


Despite this resistance, Rocky Mountain Power announced plans in 2023 to shut down Hunter and Huntington by 2032 and transition to cleaner energy sources. However, in 2024, these closure dates were pushed back to 2036 and 2042. This delay raises concerns about the feasibility and timeline of their plans, suggesting that these plants may continue polluting for even longer.


Ways to take action

Let’s work together to reduce pollution, especially invisible ozone pollution that will impact us this summer. There are many ways to reduce ozone pollution both individually and collectively in our state. On an individual level, you can: 

Drive Less

Reduce vehicle exhaust by using public transit, carpooling, or driving sparingly

Avoid Idling

Turn off your engine when parked to minimize emissions.

Upgrade Appliances

Use energy-efficient appliances to reduce emissions.

However, it’s essential to remember that systemic change is needed, especially considering that our ability to get from one place to another still relies heavily on cars. Therefore, collective action is necessary to ensure we develop the policies and regulations needed to protect our communities from ozone pollution. Sign up for our community lobbying program, to advocate for change on a systemic level here. 

TAKE ACTION! Clean Air for Parks and People

Utah’s ozone pollution is a major concern for everyone, especially those who participate in outdoor activities and cherish our state’s natural beauty. Many of the same pollutants that contribute to invisible ozone, also form visible haze in Utah that diminishes the stunning landscapes of our beloved Mighty 5 national parks

We need your help to bring attention to this issue and strengthen air pollution standards. Share your outdoors stories about how our national parks and wilderness areashave positively impacted your life. Tell us why air quality matters to you and how air quality in these places has changed your experience. By raising awareness and holding polluters accountable, we can work together to protect Utah’s environment for future generations.


Air Plan Disapprovals; Interstate Transport of Air Pollution for the 2015 8-Hour Ozone National Ambient Air Quality Standards. (2023, February 13). Federal Register. https://www.federalregister.gov/documents/2023/02/13/2023-02407/air-plan-disapprovals-interstate-transport-of-air-pollution-for-the-2015-8-hour-ozone-national

COBI. (n.d.). Retrieved May 19, 2023, from https://cobi.utah.gov/2023/1/issues/20444

US EPA, O. (2015, May 15). Ground-level Ozone Pollution [Other Policies and Guidance]. https://www.epa.gov/ground-level-ozone-pollution

US EPA, O. (2016, June 21). Ozone Designation and Classification Information [Data and Tools]. https://www.epa.gov/green-book/ozone-designation-and-classification-information

US EPA, O. (2022, February 10). Good Neighbor Plan for 2015 Ozone NAAQS [Other Policies and Guidance]. https://www.epa.gov/csapr/good-neighbor-plan-2015-ozone-naaqs