March 1, 2008
Could freeways hold the answer to Los Angeles schools’ pollution problem?
Los Angeles public schools are in a bind. Overcrowding has reached such levels that teachers have had to share their classrooms, cutting the overall academic calendar by up to 17 days while forcing students to sit through school in shifts year-round. One middle school squeezes 2,700 students into a facility designed for 800. The most obvious remedy, building more space, is complicated by a 2003 state health-and-safety law that bans most school construction within 500 feet of a freeway. Los Angeles has 24 freeways, covering 250 miles. That’s like telling Venice not to build by water.
A partial solution is emerging in the least likely place: the freeways themselves. Douglas Hecker and Martha Skinner, of the South Carolina design firm Field Office, have devised a highway-barrier system that would replace sound walls with a porous pollution-combating cement shield. Though not fully developed, Super Absorber, a runner-up in the 2007 Metropolis Next Generation Design Competition, would digest noise, light, and, most pressingly, toxic air particles—as many as four billion tons a year if implemented nationwide. No project has been launched, but the husband-and-wife team is in talks with the L.A. Unified School District. “This is a pretty simple thing that could have a real impact on our environment,” Skinner says, “if we’re able to do it.”
The operative feature of Super Absorber is TX Active, a patented cement containing titanium dioxide, a common ingredient in paint and sunblock. When exposed to sunlight, titanium dioxide oxidizes pollutants, such as carbon monoxide and volatile organic compounds, and transforms them into simple salts. The Italian company Italcementi Group developed the cement eight years ago as a self-cleaning building material for Richard Meier’s Jubilee Church, in Rome. By accident, researchers discovered that it killed smog too. Italcementi claims that it slashes emissions by 50 percent when smoothed over 15 percent of a large city’s surfaces, a potential Hecker and Skinner hope to maximize in Los Angeles. Using a 3-D modeling program, they’re on the hunt for the best configuration, layering and pocking the cement for the greatest effect. “Every pore is generating more surface area for absorption,” Hecker says. “This is being weighted by three different criteria—light, sound, and pollution—and has to eventually produce a wall that is structurally stable.”
Field Office entered the picture at an especially desperate time for the school district. A study had just been published showing that children who live near freeways suffer significantly diminished lung function. Pressure was mounting on LAUSD to reevaluate its $20 billion construction program, which includes five new schools less than 500 feet from an interstate. Ah’be, a landscape-design consultant for the district, turned to Hecker and Skinner. Could they erect Super Absorber at Central Region High School #15, a planned nine-acre campus straddled by two major freeways, where smog was an obvious concern? “It just seemed like an innovative project,” says Megan Horn, an architect at Ah’be. “It fit really well with what we were doing.”
The technology is still very much in development, of course, and experts have raised doubts. “My guess is that you’re not likely to see much benefit,” says John Froines, a UCLA toxicologist who studies health risks associated with pollution. He worries that the most dangerous smog particulates will escape the wall’s reach. Hecker acknowledges that there are limitations. “It’s not this project alone that’s going to come and reduce pollution in the city,” he says.
Last July, a day before Hecker and Skinner were scheduled to fly to Los Angeles to meet with LAUSD officials, the district put the Central Region project on hold. Health concerns were too great. The pair traveled cross-country anyway and met with the school district. “They were very enthusiastic,” Skinner says. “And they wanted to make the project bigger. These schools are all by the highways, but the highways are all over the place, so it’s kind of a Catch-22. For that reason, the project’s even more significant.”