Report names Sequoia-Kings Canyon nation's smoggiest park

A new report released by three conservation groups ranks Sequoia-Kings Canyon as America's most ozone polluted national park, the National Parks Conservation Association (NPCA), Our Children's Earth and Appalachian Voices analyzed National Park Service data to write "Code Red: America's Five Most Polluted National Parks," which updates a 2002 report, evaluates more parks with extensive air pollution monitoring and now includes air quality trends.

"In 1977 amendments to the Clean Air Act gave special protection to the national parks in this country. They were designated places in which we must have pristine air," said Laura Whitehouse, NPCA's Central Valley Field Representative. "This means that visitors to our national parks expect to find a place where they can escape urban air pollution. But the reality is that they are exposed to some of the most unhealthy air in the country. Code Red should serve as a call to action to state and federal decision makers to clean the air in our parks and communities."

With 370 unhealthful air days during the report's study period of 1999 through 2003, park visitors and staff had more occasions on which to be cautious about ozone pollution exposure than did people in Atlanta, New York or Washington, D.C. And the levels of ozone pollution in two of the park's most popular areas, Grant Grove and Giant Forest, can exceed even those in Los Angeles, which topped the list with more than 400 unhealthful air days. Ozone, which contributes to smog, damages the lungs of humans and is especially hazardous for children, those with heart and respiratory ailments such as asthma and the elderly.

“Recent reports confirm ozone and other pollutants that contribute to smoggy and hazy skies do have long-term health effects,” said Tiffany Schauer, executive director of Our Children's Earth Foundation. “We know that our national parks, places we visit with our children every year, are suffering from air pollution much like that in our cities.”

Surrounded by mountain ranges on three sides, the San Joaquin Valley, a 25,000 square mile area from Stockton to Bakersfield, is the fastest growing area in California and geographically situated to trap pollution. The mountains eventually block coastal air coming from the north, pushing the polluted mass into Sequoia-Canyon National Parks. Air pollution comes from a variety of mobile sources including motor vehicles and diesel tractor-trailers traveling on two major highways, power plants, refineries, and agricultural equipment and activities.

The pollution not only affects the air quality in Sequoia-Kings Canyon, but also damages plants and costs farmers an estimated $200 million annually. Ozone can damage and kill leaves, affecting a plant's ability to produce food. In turn, this can reduce plant growth and resistance to diseases and pests, potentially leading to long-term effects on forests and ecosystems. A broad range of plants, from sequoia seedlings and ponderosa pines to tulip trees and blackberries are sensitive to ozone pollution. In Sequioa-Kings Canyon, Jeffery and ponderosa pines are among 28 plant species especially susceptible to ozone damage.

And that pollution could be affecting the health of communities as well as park visitors. Much like sunburn affects the skin, ozone inflames the lining of the lungs, causing permanent damage with repeated exposure. Symptoms include shortness of breath, coughing, wheezing, and throat irritation. EPA estimates that nearly one-third of U.S. citizens are at a higher risk for experiencing health problems from ozone, including children, people suffering from respiratory diseases such as asthma, and otherwise healthy adults who are active outdoors. Of the Valley's more than 3.5 million residents, up to 13 percent suffer from a breathing disorder. In Fresno County, at the heart of the Valley, more than 16 percent of all children suffer from asthma, which is twice the national average.

In Central California, most park air pollution comes from a variety of mobile sources including motor vehicles and diesel tractor-trailers traveling on two major highways, power plants, refineries and agricultural equipment and activities. None of the 13 parks with long-term ozone monitoring in this study have seen statistically significant improvement in their ozone pollution levels.

Hazy skies also trouble the park and lessen the quality of park visitors' experiences. Views that should stretch 122 to 158 miles average only 39 miles in the summer. And acid snow poses problems for the parks as well. Although Sequoia-Kings Canyon receives less of the pollutants that compose acid precipitation, nitrogen and sulfur, than other parks in the study, the park is greatly affected. Snowmelt in the spring and summer can mean acidified streams that place creatures such as the California newt at risk.

Code Red ranks the following national parks as the five most polluted:

1. Great Smoky Mountains National Park in Tennessee and North Carolina

2. Mammoth Cave National Park in Kentucky

3. Shenandoah National Park in Virginia

4. Acadia National Park in Maine

5. Sequoia-Kings Canyon National Parks in California

The rankings were based on three categories - visibility, ozone and acid rain. Sequioa-Kings Canyon ranked first in the nation for ozone pollution, fourth in visibility and ninth for acid rain, although only a few dozen of the 388 National Parks monitor air quality.

Conditions at Sequoia-Kings Canyon national parks, like others on the list, have not significantly improved since the most recent Clean Air Act Amendments were passed in 1990. Many power plants and industrial facilities continue to operate with limited pollution controls as proposed sources threaten to incrementally add more pollution to the unresolved problem. And this year, the EPA designated several national parks among areas in which the air is unhealthful and violates the federal health standard - Acadia, Shenandoah, Great Smoky Mountains, Rocky Mountain, Joshua Tree, Yosemite, and Sequoia-Kings Canyon national parks along with Cape Cod National Seashore. These findings echo those in Code Red: America's Five Most Polluted National Parks, which offers recommendations for addressing national park pollution.

Although agricultural equipment, which factors in to state air quality problems, will begin permitting processes for the first time this year, emissions reductions from this program will not be evident for some time and more reductions will be needed to improve air quality. Strong implementation of critical measures already adopted, such as California's AB 1493, would reduce automobile greenhouse gas emissions in the state. Fully funding the Carl Moyer Program, through proposed legislation such as SB 403, would help shoulder some of the capital costs associated with purchasing cleaner than required vehicles and equipment that would help clear the air for parks and California. AB 198, currently before the legislature, would also shift state tax incentives for purchases of heavily polluting vehicles to purchases of clean vehicles at no net cost to the state.

"Our national parks should provide refuge from the problems and hectic pace of everyday life," said Whitehouse. "Visitors should not have to worry that enjoying the outdoors will threaten their health."

To read Code Red: America's Five Most Polluted National Parks, please go to

Appalachian Voices is a nonprofit conservation organization focused on protecting forests and communities of the Appalachian Mountain region. For more information on the effects of air pollution on forests as well as on the effects of coal mining on communities and the environment, see

Founded in 1919, the nonpartisan National Parks Conservation Association is America’s only private, nonprofit advocacy organization dedicated solely to protecting, preserving, and enhancing the National Park System. Today, NPCA has 300,000 members. A library of national park information, including fact sheets, congressional testimony, position statements, and press releases, can be found on NPCA’s Web site at

Our Children's Earth is a nonprofit organization dedicated to protecting the public from the harmful effects of air pollution. For more information, see

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