The words can opener are enough to strike fear into the hearts of semitrailer drivers passing through Delaware.

Over the years, many truck drivers have been surprised to find out -- too late -- that the railroad bridge over West Central Avenue on the west side of town is too low for their vehicles to pass under.

The result: the roofs of their trailers peeled off -- hence the can-opener moniker.

Those mishaps occurred despite a large sign on the bridge announcing its 12-foot-7-inch clearance.

Since last fall, the city has stepped up its game to alert truckers to the risk the bridge poses.

Using a $165,000 state safety grant, the city installed a system that uses lasers to detect vehicles too tall to fit under the bridge.

When the system is triggered, it displays a message on an electronic sign warning the driver to turn back and avoid the bridge.

Although it's still too early to tell if the system will reduce the number of shredded trailer tops in the long term, city spokesman Lee Yoakum said it's already saving the city money.

From Nov. 1, 2018, to June 1, the bridge was the scene of three reported incidents and six reported turnarounds that required police assistance, he said -- the same number that occurred during the same period from 2017-18.

"The cost to the city each time the bridge is struck can run $2,000 to $3,000 for manpower and equipment," Yoakum said. "None of the three strikes since the new system went operational Nov. 1 required call-out of street crews for traffic control or cleanup, saving thousands of dollars."

The new system also has reduced the speed of semitrailers hitting the bridge, he said.

"Where we are seeing success is that the severity of the bridge strikes is much less over the last seven months. No system will stop all drivers, but the new warning signs have dramatically reduced the seriousness of any incidents, thus reducing traffic delay, cleanup costs and city staff time of police and public works," Yoakum said.

The system was launched with three goals, he said: to warn drivers to turn around; to prevent high-speed impacts that destroy trailers; and to reduce the cleanup incurred by the city.

"We are seeing early success with all three of those," Yoakum said.

"We know from residents' reports that more trucks are turning around, that don't require police assistance and are not striking the bridge.

"We are cautiously optimistic, but with only seven months of data on a problem that has existed for decades, we really need to have a bigger database," he said.

Yoakum said despite the city's efforts, some drivers ignore the warning signs.

"The real solution is for the drivers of vehicles taller than the posted bridge height to read the signs and obey the warnings," he said. "In our mind, that's not that difficult."

The city's Access Delaware website -- -- contains multiple pages on city street and transportation projects.

It notes lowering the pavement under the railroad bridge would cost $1 million.

It also would require rebuilding several hundred feet of Central Avenue on both sides of the bridge and would demand storm-sewer upgrades and affect the driveways of a number of residences and businesses.

The laser-activated system, the site says, was chosen in part because studies show motorists are more likely to obey a traffic-control device that abruptly turns on, versus one that operates continuously.

The system's two large overhead flashing message boards are activated by laser detectors 1,000 feet ahead of the bridge. Communication between the laser controls and overhead message boards is by radio.

Electric lines power the laser equipment, while the overhead signs are solar-powered.

The city traffic engineer receives an email each time a truck activates the system.

The planned addition of cameras would notify the police department, record video footage to provide information on vehicles activating the system and show how driver behavior changes when the sign flashes a warning, the website says.

Not all vehicles that activate the system necessarily strike the bridge, because the vertical clearance for each depends on the overall vehicle length, according to the site.