Top 10 Most Polluted National Parks in the US Revealed

The National Parks Conservation Association (NPCA) has just released its ‘Polluted Parks’ report for 2024, an update to its 2019 version that, while findings show some modest improvements, largely highlights just how contaminated our precious protected lands actually are. Interestingly, five out of the top 10 can be found in California, although it may come as no surprise since it’s a such densely populated state.

As the report points out, the U.S. national parks are home to some of America’s most iconic landscapes, magnificent wild spaces, and best-preserved cultural and historic sites. They may be federally protected, but some things they cannot be safeguarded from, including air pollution and the detrimental effects of climate change. Many may remain wild and stand as sanctuaries for nature lovers, but, as. it turns out, they are actually far from pristine. 

Although, in all their age-old majesty, they may seem unchangeable, the truth is that they depend upon delicate ecosystems to survive—ecosystems that are threatened by human-caused contaminants and conditions. The NPCA points out that the health of plants and animals that populate these habitats has been weakened, and ecosystems permanently harmed, by air pollution and climate alterations. 

Astonishingly, 98 percent of national parks suffer from haze pollution, with 97 percent rating “unsatisfactory” or “significant concern” when it comes to air quality conditions, and ozone problems that negatively affect human and animal health. Meanwhile, 96 percent of those parks contain sensitive wildlife species and natural habitats that are harmed by sulfur and nitrogen deposition in the soil and ozone pollution in the air. 

Sequoias & Kings Canyon National Parks, California. (Photo Credit: Adobe Stock/fertatay)

Sequoia and Kings Canyon National Parks rank number one among the most polluted of our country’s national parks, with “significant concern” ratings in visibility, health and nature, as well as threats like wildfire, drought and invasive species. The wealth of industry that takes place throughout the Golden State—such as oil and gas, and agriculture—along with an usually high number of vehicles are largely responsible for the excessively dirty air. 

Top 10 National Parks With Unhealthy Air

1. Sequoia & Kings Canyon National Parks – California
2. Joshua Tree National Park – California
3. Mojave National Preserve – California
4. Yosemite National Park – California
5. Carlsbad Caverns National Park – New Mexico
6. Death Valley National Park – California
7. Indiana Dunes National Park – Indiana
8. Guadalupe Mountains National Park – Texas
9. Rocky Mountain National Park – Colorado
10. White Sands National Park – New Mexico

Carlsbad Caverns National Park in New Mexico. (Photo Credit: Allison/Adobe)

Top 10 Worst National Parks for Hazy Skies

1. Sequoia & Kings Canyon National Parks – California
2. Gateway Arch National Park – Missouri
3. Mammoth Cave National Park – Kentucky
4. Carlsbad Caverns National Park – New Mexico
5. Indiana Dunes National Park – Indiana
6. Hot Springs National Park – Arkansas
7. Death Valley National Park – California
8. Channel Islands National Park – California
9. Dry Tortugas National Park – Florida
10. Pinnacles National Park – California

---

For the latest travel news, updates and deals, subscribe to the daily TravelPulse newsletter.

Topics From This Article to Explore