The Cleanest (and Dirtiest) Cities in America

If you're looking for a new city to call home—or even just choosing a holiday destination—you’ll want to read this list first! Our collection of the cleanest and dirtiest cities in the United States is based on research from The American Lung Association’s pollution rankings, which consider factors like litter, eco-friendly initiatives, and air pollution. The results may surprise you, so get ready to discover America’s best—and worst—kept cities.

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Cleanest: Honolulu

Perhaps it doesn’t come as a surprise that Honolulu tops the American Lung Association’s cleanest cities list. Whether you live there or are just visiting, you can enjoy pristine beaches and fresh air. The tropical city and the state of Hawaii is committed to improving its green initiatives. Because of tourism and the military, it heavily relies on fossil fuel but has set a goal to use 100% clean energy by 2045.

Related: 20 American Towns with Perfect Weather

Cleanest: Dallas-Fort Worth

Discover a place where cleanliness and social justice go hand in hand. In Dallas, the Clean Slate program pays people who are homeless to help clean up the city’s streets, contributing to a more beautiful city in more ways than one. While it does suffer from high ozone days, it is one of the cleanest metropolitan cities in the country according to the American Lung Association.

Cleanest: Denver

The poor air quality that has plagued Denver as a result of ozone pollution is being remedied through the city’s membership in the Department of Energy-sponsored Clean Cities Coalition. This program funds and implements hybrid and electric technology, fuel efficiency, and community engagement. 

Cleanest: Orlando

Meet a city with its own Downtown Clean Team. Its mission is to improve the urban experience by picking up litter and removing graffiti. Volunteers do their part to make this city a poster child for clean streets and clean air.

Related: 12 Destinations You Should Actually Visit During the Off-Season

Cleanest: Burlington

Other towns and cities should look at Burlington for an example of a city committed to sustainable living. The Vermont city was the first in the country to use 100% renewable energy for its residents’ electricity needs. The city is focused on educating its residents about the dire effects of climate change and upgrading its water infrastructure. On the American Lung Association’s clean city list, Burlington is one of the cleanest metropolitan areas and has one of the cleanest ozones.

Cleanest: Wilmington

Wilmington, NC ranks in the top 25 on all three of American Lung Association’s clean cities lists: ozone, year-round particle pollution and short-term particle pollution. Considering how much of an influence the water has on the city—a river runs through it as well as there being nearby beaches—an eco-friendly lifestyle is important.

Cleanest: Syracuse

Syracuse might be best known for its college basketball team and bitter winters, but not discussed much is its excellent air quality! The central New York city had no days in the unhealthy level for short-term particle pollution and is one of the cleanest cities for year-round particle pollution.

Cleanest: Tampa-St. Petersburg, Florida

Tampa fosters a culture of urban stewardship, with both employees and volunteers keeping the city beautiful. In addition, at the University of South Florida, you will find the Clean Energy Research Center—a great resource for scientists, students, and advocates.

Related: The 30 Best Towns to Move to for Retirement

Cleanest: Lincoln

Since 2009, Lincoln, NB has been focused on sustainable initiatives through its Cleaner Greener Lincoln plan. And it seems to be making an impact! Lincoln is one of the six cities that’s ranked on all three American Lung Association’s cleanest cities lists.

Cleanest: Bellingham

Government policies are important, but so is a culture of action, and Bellingham has one of the strongest local activism communities. The city, sandwiched between Seattle and Vancouver, has a clean ozone and minimal particle pollution. Plus, with its many lush green spaces, it’s the perfect place to celebrate Earth Day—every day.

Related: The Best U.S. Cities for a Summer Staycation

Dirtiest: Los Angeles

Los Angeles continues to be one of the most polluted cities in America according to the American Lung Association’s Most Polluted Cities list—a fact that’s not surprising given the region’s population density, traffic issues, and rising temperatures. For 19 out of 20 years, it has topped the list for ozone pollution, as well as ranking high for short-term and year-round particulate matter. 

Dirtiest: Fresno-Madera

Another California city tops the list of America’s most polluted: the nation’s “Raisin Capital,” Fresno. Air pollution from agriculture and industry can be severe here, and such pollution can lead to numerous ills, including heart damage, coughing, headaches, and even the flu.

Dirtiest: Visalia

Wikimedia Commons via VISALIA2010

A third smog-filled California metropolitan area (10 California cities rank in the top 25 in the overall report) is Visalia-Porterville-Hanford, where there are close to 9,000 cases of pediatric asthma and over 25,000 cases in adults. As this is a highly productive agricultural region, pesticides are big contributors to ozone and groundwater pollution.

Related: Pedestrians Only: 20 Car-Free Places in America

Dirtiest: Fairbanks

One surprise on the American Lung Association’s list of the dirtiest cities: Fairbanks. While the city is one of the cleanest metropolitan areas in the country for ozone,  Fairbanks suffers from dirty air, especially in the form of 24-hour particle pollution and annual particle pollution. Improved monitoring of pollution has identified that this is a bigger problem for the city.

Related: These 30 Places Have the Worst Weather in America

Dirtiest: Salt Lake City

Despite being known for its outdoor activities, Salt Lake City suffers from poor air quality. A study from the American Thoracic Society concludes that although pollution-related deaths in America are on the decline, there has been a sharp uptick in the Utah capital. 

Dirtiest: Pittsburgh

Elevated soot levels in Pittsburgh, famous as one of America’s first industrial cities, continue to plague residents today. That said, city officials and residents have been hard at work to improve environmental protections and quality of life.

Dirtiest: New York City

Another city that has made significant improvements in air quality is New York—yet smog still hangs in the air. With the status of national environmental policies uncertain, the pressure is on local regulators and innovators to find solutions. Air pollution poses a thorny problem, however, because lax laws in nearby industrial areas can impact the quality of the city’s air.

Dirtiest: Las Vegas

Drought, heat, and climate change all contribute to the thick air obscuring Sin City. In recent years, however, idle reduction requirements and other emissions-lowering efforts have been making some headway in the city’s pollution problems.

Dirtiest: Philadelphia

Despite being one of the 25 cities most polluted year-round by particle pollution, Philadelphia has been making improvements. This past year has been its lowest annual level ever. 

Related: The 20 Friendliest Cities in America

Dirtiest: Cleveland

Although it has made great strides in reducing the number of dangerously high ozone days, Cleveland still retains a spot on the American Lung Association’s list of shame. While it has reached its lowest level ever for annual particle pollution, it still sits at number 9 on the list. Rates of respiratory illnesses like asthma, COPD, and lung cancer are relatively high in the region, as a result of excessive particle pollution and weather patterns.