- The Washington Times - Thursday, December 26, 2002

AMHERST, Va. (AP) About seven miles west of the town of Amherst, a bridge runs over the Buffalo River on U.S. 60. But this is no ordinary bridge it heats up when the temperature drops to about 40 degrees. At least, it's supposed to.
Since it was built six years ago, the state's only heated bridge has faced a series of setbacks, and now it is broken again.
But research scientist Edward Hoppe, who works for the Virginia Transportation Research Council in Charlottesville, hasn't lost hope for the bridge and the $181,500 technology that heats it.
"We are confident that it will work," he said.
To work, sensors in a cinder-block shed next to the bridge would trigger a boiler that heats a chemical that works like antifreeze. The chemical and hot water then should pump through pipes that span the length of the bridge. That mixture is supposed to heat Freon, the vapors of which ideally would distribute through the bridge, condense and be recycled.
The bridge originally was designed to test this technology, said Amherst resident engineer Mike McCormack, adding that valuable information already has been gleaned from it.
By heating the bridge through grant money, officials with the Virginia Department of Transportation (VDOT) hoped to avoid using damaging de-icing chemicals that could increase the need for bridge repairs. Also, the system was designed to lower the number of accidents by melting ice, Mr. McCormack said.
However, he said, "it's kind of had fits and starts with working."
The first major trouble was revealed after a 1998 snowstorm. The heat failed to kick in when the temperature dropped.
Mr. Hoppe said researchers fixed the problem, but then discovered problems with the fluid system in the bridge. Researchers extended the testing period, which was supposed to end in 1998, through 2000.
"We found the Freon wasn't conducting the heat throughout the whole bridge system," he said. Researchers then experimented with different chemicals.
In 2000, they discovered ammonia worked best, Mr. Hoppe said. But he said there hasn't been a significant snowstorm to test the system.
The season's first snowfall in early December didn't serve as a test, because Mr. Hoppe earlier found that the computer system wasn't working. "So we ordered a new circuit board," he said.
Once the computer is fixed, Mr. Hoppe said, he is sure the bridge will work because the technology performed well when a small amount of snow fell in February 2001.
As for the rest of Virginia, Mr. Hoppe said he is not aware of any plans to build another heated bridge.
However, VDOT is testing a bridge with de-icing sprays in Fairfax County, and is considering building more. This type of system costs about $27,000 to install.
Nozzles on this bridge spray chemicals on the surface of the road. This type of system has been used on many bridges nationally.
Mr. Hoppe and Mr. McCormack said the heating technology is worth more investigation because the spray system does nothing to prevent damage from chemicals on the bridge.
"So the jury's still out in some respects," Mr. McCormack said.
Mr. Hoppe said the technology could be effective in preventing accidents, especially on a bridge around a curve or on a steep grade.
"The technology is viable, but you have to spend more time maintaining and making sure the control system works," Mr. Hoppe said.
Mr. McCormack said that if VDOT does build another heated bridge, it probably will have fewer problems because of the Amherst experience.
"I'm sure there could be some lessons learned from this one that if they decided to do it again, it could be more cost-efficient," he said.

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