If Baltimoreans notice a new spring in their step, it might just be the sidewalks.
In a pilot program that officials hope benefits the city's bottom line almost as much as the environment, Baltimore is joining dozens of cities across the country in testing rubber sidewalks - made from used tires - that are less prone to damage from tree roots and ice.
Rubber walkways, which were installed yesterday in one-block test sites at the Inner Harbor and in Charles Village, make use of otherwise worthless tires and also allows more rain to seep into the ground - providing extra water for trees and reducing the runoff that can overload the city's antiquated storm water system.
And, yes, they do bounce - a little.
"All you see is tires that are being thrown in the dump," said Alfred H. Foxx, director of the city's Department of Transportation. "This is one way to take those used tires and recycle them and use them for something that's beneficial for the public."
Baltimore has more than 3,600 miles of sidewalks and the city spends about $2 million a year to repair cracks and uneven pavement. The sidewalk fractures are usually caused by tree roots reaching for water in an urban environment where much of the ground is paved. To fix a cracked sidewalk, crews jackhammer the concrete, cut out the root and repave.
But the rubber sidewalks, which come in panels like floor tile, let water trickle down through the seams. And when roots receive water, they tend to grow horizontally, along the sidewalk or street, rather than up through it. That, Foxx said, should ease the sheer number of sidewalk repairs the city must complete every year.
The job is time-consuming - and obviously not so good for the trees, either.
The technology might also reduce the number of trip-and-fall lawsuits the city faces every year. Because the rubber doesn't crack, it is less likely to trip up walkers. Between 2004 and 2006, about 201 people filed claims against the city after falling on a sidewalk, according to the Transportation Department. Baltimore paid roughly $43,000 to settle some of the claims over this period.
About 60 cities, including Washington, are either testing or using the sidewalks, which are made by a California-based company that is appropriately named Rubbersidewalks. Lindsay Smith, president and CEO of the company, said she began developing the concept in the late 1990s after she saw city workers cutting down trees in her own neighborhood. The company started selling the product in 2004.
"I learned that they were cutting down these beautiful, healthy trees because they were breaking the concrete and I thought that was just absolutely crazy," Smith said. "It's a true urban problem that was sort of kept a secret. Cities didn't want to admit that they have this problem because they didn't know how to solve it."
Smith said the underlying idea is Richard Valeriano's. As the legend goes, the public works inspector from Santa Monica, Calif., was inspired in a dream.
Each panel, at 5 square feet, is made up of about five used tires ground down into a powder that is bound and then baked into place - "like a rubber cake," Smith said. The panels, which can be replaced individually, give more than concrete. Walking on them is similar to walking on a high-performance running track.
They may even be easier on knees and elbows during a fall, but children wanting to sign their initials in freshly poured concrete will be out of luck.
One drawback: The panels cost considerably more than traditional sidewalks, about $15 per square foot for material and installation. By some press accounts, that's two or three times the price of concrete.
Baltimore officials said they hope the material will eventually pay for itself because it requires less frequent maintenance. The company is also expected to open a factory soon in New York, which will cut down on shipping costs from the West Coast.
Both Baltimore and Washington want to see how well the sidewalks perform in the winter - or, more to the point, how they hold up after weeks of abuse from salt and metal snow shovels. In Baltimore, the rubber walkways are being installed on Pratt Street, between South and Commerce streets, and on University Parkway, between Charles and St. Paul streets. The city spent about $60,000 for the pilot program.
Foxx said city crews will monitor the test sites for a year and seek public input. If the rubber proves durable, the sidewalks could be expanded to more neighborhoods. The sidewalks are part of a larger effort by Mayor Martin O'Malley's administration to improve the health of city trees that has included more regular pruning and a pledge to double the city's canopy over the next three decades.
"If [the roots] are getting water consistently they'll keep growing out," said the city's arborist, Rebecca Feldberg, who stood along the Pratt Street test site where a number of relatively young sophora japonica trees rustled in yesterday's breeze. "We're hoping that [the sidewalks] will be more flat than with concrete."