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Annual Progress Report, 2012

 Clean Air

Air Quality Improves Across Region

Since 1970, the Pacific Southwest’s population has doubled, while the distance travelled by motor vehicles has tripled. Nevertheless, air quality has improved dramatically everywhere – though some areas still have a long way to go.

Decades of Work Brings Results »

We all breathe healthier air thanks to federal regulations stemming from the Clean Air Act of 1970 and the Amendments of 1977 and 1990 – such as the phaseout of leaded gasoline, and cleaner car and truck engines – along with actions at the state and local level intended to meet or exceed federal requirements (see charts below).

The trend toward healthier air is evident even in California’s South Coast (the Los Angeles area) and San Joaquin Valley – though these areas still have some of the nation’s worst air quality. Both areas have met clean air standards for sulfur dioxide and carbon monoxide consistently since 2002. But levels of ozone (smog) and particulates, despite continuing improvement, have failed to meet health standards.

Since 2000, there have been new, tougher standards for ozone and particulates. In the 1990s, health studies found exposure to ground-level ozone to be harmful at lower levels and shorter time periods than previously known. Particulate pollution – dust, soot, and aerosols – was found to be harmful at smaller sizes, which can penetrate deeper into human lungs.

For these reasons, EPA more than a decade ago added new air quality standards for 8-hour exposure to ozone, and for fine particulates, known as PM2.5. Under the Clean Air Act, states are responsible for submitting clean air plans to EPA that show how and when they will achieve the standards.

Fighting Unhealthy Air in California

Fine particulate pollution levels – first measured in 1999 – had improved by 43% in the South Coast by 2010, but only 14% in the San Joaquin Valley. Further clean air measures were needed.

New Plans Set Aggressive Goals »

In 2011, EPA approved California’s clean air plans for the Valley and South Coast, which include most of California’s population. One goal of the plans is to achieve the national health standard for 8-hour ozone exposure within 12 years.

For the San Joaquin Valley, another goal is to reduce fine particulate pollution by 34% from 2009 levels, meeting the PM2.5 standard by the end of 2014. The California Air Resources Board (CARB) predicts that on average, this will prevent 640 premature deaths per year in the valley.

As part of these plans, CARB had submitted three of the most innovative mobile source emissions rules in the nation, including the In-Use Diesel Truck and Bus rule, which affects more than 1 million diesel engines in California.

Dozens of local rules were upgraded to further reduce pollution from specific industries. For example, a San Joaquin Valley rule regulating confined animal feeding operations will reduce smog-forming volatile organic compound (VOC) emissions by 25 tons per day.

This year, EPA is preparing to act on at least 10 more San Joaquin Valley rules, including emissions limits for fumigants, oil wells and pipelines.

“When the Clean Air Act was signed over 40 years ago, the goal was to make sure every single American could breathe healthy air," says EPA Regional Administrator Jared Blumenfeld. "That promise has still never been realized in the San Joaquin Valley, so we’re working with CARB and the Valley’s Air District on a number of actions to make it happen.”

Clean Technology for Cleaner Air

This new diesel-electric hybrid locomotive, purchased with partial funding from EPA, is cleaner and uses 50% less fuel than its predecessor.

Advances in technology have brought far cleaner engines to new diesel trucks and locomotives. Now the challenge is to get cleaner engines into existing vehicles, which last for decades, and to speed adoption of other clean-tech advances.

Collaboration Speeds Deployment »

EPA is making grants to vehicle fleet owners to hasten the replacement of dirty diesel engines, especially in areas with unhealthy air, like the South Coast and San Joaquin Valley.

In January 2012, EPA announced $7.9 million in grant funds to help fund cleaner diesel engines throughout the Pacific Southwest as part of the West Coast Collaborative. One of these grants helped pay for cleaner locomotives in the San Joaquin Valley, like the diesel-electric hybrid pictured at right. It’s not only cleaner, but uses 50% less fuel than its predecessor on a freight line between Lodi and the Port of Stockton, Calif.

In February, EPA partnered with CARB, the South Coast Air Quality Management District and the San Joaquin Valley Air Pollution Control District to convene in Bakersfield with local governments, vehicle fleet owners, and dozens of innovative companies to accelerate development and deployment of cleaner technology for trucks and buses, including battery-electric, fuel cell, and hybrid vehicles. California’s first electric school bus made its public debut there.

In parts of the Los Angeles area, diesel emissions from beer and soft drink delivery trucks are a significant part of the problem. To help ratchet down these emissions, EPA issued a $1.5 million grant to the South Coast Air Quality Management District to help pay for cleaner engines on beverage trucks in the heavily-impacted Boyle Heights area. The new fleet hit the roads in February 2012.

EPA Spotlight


Doris Lo, Frances Wicher and Wienke Tax

Doris Lo, Frances Wicher and Wienke Tax (left to right) have over 60 years of combined experience at EPA working on air quality plans, permits, rules and enforcement. Most recently, the three worked closely to evaluate ozone and particulate matter plans for California’s South Coast and San Joaquin Valley, and approve state and local regulations for these pollutants. Their expertise is much in demand, as California continues to develop new air quality plans for more stringent health standards.

Air Quality Trends

Ozone (smog) Levels, *1980-2010
PM2.5 (fine particulate) Levels, *2000-2010

*Blank areas in graph mean that air quality met national health standard during that period. For details on the data sources, go to our Air Trends website.

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