Boston — Graffiti wars. Each night, wielding brushes and spray cans, vandals leave their signatures and slogans on the face of urban America.
Each day, wielding solvents and resolve, cleanup crews try to delete the mischief.
It's an endless cycle. It costs urban America millions of dollars each year. Rarely do cities win. Usually, they just try to contain the foe.
Today new weapons -- from stiffer chemistry to elaborate air-water guns -- are being enlisted to help cities try to slow the defacing.
Technology alone, of course, is no answer to the problem. It's as much a social one as anything else. For this reason, some cities continue to try to work with some youth who create the problem and prosecute others who won't put down their brushes and spray cans.
Cleaning up graffiti is not like scrubbing your kitchen floor. For one thing, marks have to be removed from many surfaces. Vandals mar everything from stainless-steel subway cars to delicate sandstone statues to wooden benches. ``If it doesn't move, they write on it,'' says Marie Sarchiapone, who heads up a four-member team cleaning up graffiti in New York's Central Park. ``But they haven't hit the squirrels yet.''
For another, inks and paints have become more difficult to remove. This is no conspiracy against urban America by paint manufacturers. They contend they are trying to produce what most consumers (vandals excluded) want in paints -- ones that are long lasting and don't fade quickly. Even if easier-to-remove paints were available, though, resourceful defacers would probably find other weapons.
In New York, for instance, youth have been known to steal the blue inks used in grocery stores to mark food items. ``These are extraordinarily permanent,'' laments Edgar Slaght, a chemical engineer with New York's Metropolitan Transit Authority (MTA).
A key strategy is to strike quickly. The quicker cleanup crews can get to graffiti, the easier it is to take off. It also helps discourage scribblers altogether: Because many do it for recognition, removing it fast takes away their incentive to do it again.
Plenty of tools exist today to do this, but all, it seems, have their warts. One of the easiest methods remains simply painting over marked surfaces. The trouble is, many items, like marble statues, simply can't be painted.
Cities are also increasingly turning to ``graffiti-resistant'' sealers and coatings for public buildings and surfaces. These can be either clear coverings or paints. They are usually nonporous. Thus, offensive markings scrawled on later don't penetrate so deeply. Result: the graffiti is easier to scrub off and the underlying paint is less likely to wash away during cleanup.
These coatings can be effective. In Philadelphia, the Southeastern Pennsylvania Transportation Authority (SEPTA) has used impervious polyurethane-based paints when redoing the city's bus and rail fleet over the past five years. Cleanup crews, as a result, have had a much easier time of it, says SEPTA's David Murdock.
In Los Angeles, graffiti busters with the Community Youth Gang Services Project -- a program to use former gang members to defuse gang violence -- have been testing a new two-step sealer. First a surface is painted. Then a clear coat goes on. The two bond and become impermeable. The product is one of the ``best'' things around, says Henry Toscano, whose community services cleanup crew has used it to help protect, among other things, the city's ``Hollywood'' sign.
Coatings aren't elixirs, though. When used on stone and concrete surfaces, in particular, they can pose problems. Some yellow with age. Others crack and peel. If they seal too well, some trap moisture in a wall, which, when it freezes, will crack off chunks.
Sealers and coatings can also be highly toxic and require experienced crews to use them. Cleaning solvents require similar care in handling. ``It if works, the safety people don't like it. If the safety people like it, it doesn't clean the buses,'' says Terry McGuigan, director of bus maintenance for the Chicago Transit Authority. Chemicals exist that can be used safely to remove most graffiti. But marks that penetrate deeply often leave ``ghosts.''
Even with these limits, however, cities are making headway. Ms. Sarchiapone's crew has removed 45,000 square feet of graffiti in Central Park in three years, most of which hasn't reappeared. New York's MTA expects to scrub one-third of its subways clean by year's end, using solvent sprayers and hand-cleaning methods.
Cities, meanwhile, are looking for new potions. The National Park Service recently tested a high-pressure gun on Grant's Tomb in New York. Developed by a Japanese company, the device shoots out air and small amounts of water at 20,000 pounds per square inch. It removed even ghosts on the granite monument. But it is a time-consuming process, and some Park Service officials wonder what damage such a high-pressure spray might do to softer surfaces over time.
A British firm has come up with a coating that, in addition to blocking scrawls from seeping into walls, slows the drying of graffiti. Thus it can be removed days later. Skeptics, though, say there's only one catch: keeping wet graffiti off people's clothes.
All of which means there is no pat technological answer. ``We can remove graffiti, but it's the amount that is the problem,'' says Joseph Bresnan, director of planning and preservation for New York's Department of Parks and Recreation. ``We're outnumbered.''
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