The latest figures from the state's air pollution control districts show a dramatic improvement in the past decade, but the air in most of the state is far from pristine, and the San Joaquin Valley's air quality remains the worst in the nation.
This report shows despite more people and more cars on the road, California's air quality is improving. Marked by lower ozone levels less particulate matter.
The report suggests even the air in the San Joaquin Valley is getting better. The number of unhealthy air days dropped dramatically between 2000 and 2012. In Fresno County there were 66 unhealthy air days in 2000 and just 8 last year. Similar dramatic drops were noted in every other Valley county.
With cars and trucks contributing the most pollution, cleaner vehicles are a big reason for the improvement. Jaime Holt of the San Joaquin Valley Air Pollution Control District says business and members of the public also played a big role.
"Cars are a main part of that, cars are definitely cleaner, but really here in the Valley there's been an enormous, investment by business and industry, over 40 billion dollars has been spent by industry to make their processes cleaner put cleaner equipment on what they do so there's been a huge investment even the public's playing a role, we have our wood burning rule in the winter."
The report by the California Air Pollution Control Officers Association suggests we can't get much cleaner until new technology cleans up the internal combustion engine.
Bonnie Holmes-Gen of The American Lung Association says better urban planning needs to be part of the solution. "We cannot achieve our clean air goals with technology alone, we have to build more sustainable healthy communities and by doing that we can reduce vehicle use and get pollution out of the air."
John Capitman director of the Central Valley Health Policy Institute at Fresno State agrees vehicles are the problem. But rather than wait for all cars and trucks to be clean, we can cut the miles driven by reducing urban sprawl.
"As we talk about the new developments in Madera County or the New town Millerton Lake proposals the expansion around Friant, all that means is the city is growing out," said Capitman. "That population is growing out and that more people will be driving around, driving long distances and added to our air pollution challenge."