When a "Do Not Enter" sign just isn't enough, modern technology can go a long way to prevent wrong-way car crashes, transportation experts say.
These can range from sensors built into pavement to detect wrong-way movement to roadside video cameras. The system can alert a motorist that he is going the wrong way, either through flashing lights on roads or alongside of them, and through electronic signs.
One of the most advanced systems in the United States has been in place on Houston's Westpark Tollway since 2007. It was put in place after a pair of fatal wrong-way accidents there in 2006.
Radar detectors on the side of the road to detect a wrong-way driver. Electronic road signs then activate to tell the driver he is going the wrong way. Signs also advise other drivers: "Warning: Wrong-way driver ahead. All motorists pull to the shoulder and stop."
Video cameras automatically zero in on the driver and send the video to a central traffic monitoring center, where police are notified. Patrols get in position ahead of the driver and stop the vehicle with spike strips.
Since the system was put in place in 2007, the toll authority has stopped 19 wrong-way drivers, Assistant Deputy Chief Randy Johnson said.
"It's definitely proven to be successful," he said. "You're never really going to be able to stop wrong-way drivers. However, this technology alerts us where they have entered and allows us the chance of getting them stopped before we have a traffic accident."
But the high price tag of such systems - Houston's cost $350,000 for just the one road - limits states to using them only in locations identified as problematic, said Scott Belcher, chief executive of the Intelligent Transportation Society of America, a nonprofit group that advocates for advanced highway safety technologies.
Eileen Peters, spokeswoman for the New York State Department of Transportation, said using such technology is cost-prohibitive here, especially considering that such accidents are rare and have not happened more than once at the same location.
Belcher said that using technology to prevent wrong-way accidents will become much more common and affordable. Several carmakers and even the U.S. Department of Transportation are developing technology that will allow roads to communicate with cars to prevent accidents, including those caused by drivers going the wrong way. Cars may even automatically brake or steer away from a potential crash.