Smart Bridges Block Icy Road Hazard

State transportation officials are employing electronic brains to defeat a deadly winter enemy on six of Pennsylvania's highway bridges. So far, they report no casualties.

The system, called F.A.S.T., for Fixed Automated Spray Technology, is a system of storage tanks, pipes, sensors, and disks retrofitted into highway bridges where ice often forms an invisible cloak.

In 2000, there were 32 fatalities on the state's roadways and hundreds of accidents. But in the two years since it began installing the technology on six bridges, there have been no winter accidents reported on the six bridges using the system.

"That's no reportable accidents," said Douglas Schmitt, roadway programs manager in PennDOT's New Technology Implementation Section. "There are some accidents but not serious enough to report," he said.

Eyes Toward the Skies

Here's how the technology, now installed in at least 18 states, beats the ice: First, sophisticated weather gear monitors conditions.

Jerry Waldman, whose Swiss company, Boschung Company Inc., installs the devices in the bridges, says sensors can distinguish "between rain, snow, freezing rain, and the amount, rate [the precipitation] is falling."

The equipment actually scans the sky. "Optical beams of light monitor the precipitation particles as they're falling out of the sky."

Fully Automatic

On a bridge near Erie, Waldman pointed to highly sophisticated probes which read the roadway's temperature. When it approaches freezing, the bridge coats itself with an anti-icing fluid. The liquid shoots out of six nozzles in series of spray disks planted in the pavement.

The fluid is pumped up to the bridge from a 5,000-gallon tank, which sits beside an automated command center. According to Waldman and state transportation officials, the system runs itself.

"The entire purpose of this system … is designed to work with no human intervention," Waldman told ABCNEWS.

In snowy, windy weather, one key element of the system is that it's practically invisible. Driving across this bridge, drivers saw nothing but the pavement. There was no distraction.

Advanced Storm Warning

The system also gives dispatchers a heads up. Trucks must still salt and plow the roads, but now, with information flowing from the bridge into district headquarters on wind, precipitation, and temperature the crews know where to go ahead of the storms.

That means crews are getting to the scenes of potential accidents before they can happen.

"That's the key to this whole operation," said Schmitt.

So these smart bridges save not only time — but lives.