Brian and Lonnie Bishop had just unpacked their bags for four days of hiking in mountains near here when they glimpsed a front-page headline in the local newspaper: "Officials declare air unsafe, tell residents to 'stay inside.' "
"I couldn't believe it," says Brian, a self-employed computer consultant. "I thought L.A.'s problems with smog were long gone."
A half decade after announcing Los Angeles had its cleanest air in 50 years - and ceded the title of national smog capital to Houston - fresh concern is surfacing about the city's momentum in Windexing its skies.
A spate of hazy pollution this year culminated in the city announcing a Stage 1 smog alert last week. True, the designation lasted only 3 hours. But it was the first such alert - which brings with it an official caution about outdoor activities ranging from running to rollerblading - since 1998.
Officials are playing down the episode because of a rare confluence of extended hot weather and high-pressure systems, which cause air inversions, trapping ozone gases at lower altitudes. But independent experts say the moment has long been coming when population growth, industry expansion, and greater SUV use would overtake the area's hard-won gains of the 1990s.
And because L.A. led the nation in producing the harsher rules and tougher enforcement that led to those gains, these same officials wonder whether dramatic reductions have bottomed out nationwide.
"This may be the turning point where we as a nation may begin to lose the really impressive gains we made in the 1990s and go in the other direction," says Arthur Winer, professor of environmental-health sciences at the University of California. "If these changes are happening here, you can bet they are happening in other states and counties where there is less resolve and less stringent controls. The big issue is how to continue to compensate for industry and population growth."
The Stage 1 designation translates to formal caution from authorities for those exercising - running, hiking, biking, rollerblading, and surfing. Even sustained activity such as yard work is warned against. Besides the smog alert, officials say there have been 33 days of unhealthy air quality in the region this year, nearly twice as many as last year. One of the problems has come from increased traffic congestion, which means more cars on freeways, moving slower and idling - producing more pollutants per mile driven.
The health danger comes from ozone, a colorless gas that forms when car and smokestack emissions mix with paint fumes, other airborne chemicals, and sunshine.
The biggest ozone problems have come inland, where seaside breezes blow the emissions from tailpipes, smokestacks, off-road engines (from ships, to trains, to farm machinery), and chemicals (paints, thinners, solvents).
"This is a significant setback in our progress toward clean air and it underscores the need for further pollution control at the local, state, and federal level," said Barry Wallerstein, executive director of the South Coast Air Quality Management District. Seventy-five percent of pollutants come from off-road vehicles, which are not SCAQMD jurisdiction.
On Aug. 1, the SCAQMD governing board is scheduled to adopt its updated blueprint for how to achieve and maintain federal standards by 2010. Ideas include tougher controls on off-road engines, and "architectural coatings" from paints to rust sealers to wood stains. But the district is only one of three main entities trying to enforce and educate residents and businesses. The California Air Resources Board is responsible for 64 percent of such residents and businesses, the US Environmental Protection Agency is responsible for 21 percent and the AQMD, 15 percent.
"We need the state and the feds to put the pedal to the metal in terms of attacking some of these other polluters that have gone largely unregulated like ships and trains," says AQMD spokesman, Sam Atwood. "The lesson for us in all this and for others across the country is that we can't afford to let up on all the progress we have made against smog."