Trucks and trailers are sometimes incompatible with overpasses. When a vehicle’s too high for the overhead clearance, bam! We’ve all seen structural beams that have been battered by too-tall trucks attempting to get through and whose drivers suddenly found it wasn’t physically possible.

Often it’s a van-type trailer whose top is sheared back – “skinned,” some folks say. The bridge wins in such a contest because it's much stronger than the vehicle.

But last Friday afternoon it was a roll-off trash truck whose driver was breezing along a freeway on the south side of Columbus, Ohio. The truck carried no trash bin, but unbeknownst to him, the hoist had raised its longitudinal rails so they were sticking up like a beefy battering ram at the ready. It plunged into the large I-beam supports of a bridge, tearing down the first one and damaging three others.

This temporarily blocked the westbound lanes of the freeway (State Route 104) and, because of the bridge’s weakened understructure, transportation department officials closed several lanes of the busy boulevard above (South High Street).  This got considerable coverage from local news media, and I shot some photos from video aired by Channel 6 News.

A young couple who witnessed the crash from their car just behind said the truck driver stopped but seemed “unfazed.” His company's bosses apparently weren’t so cool about it, and a representative told the couple that they fired the driver on the spot. Police charged him with reckless operation and an overheight-vehicle violation, the Columbus Dispatch reported. 

The bridge has been hit before, the newspaper reported, but its clearance height is 15 feet, 8 inches, well above the federal standard of 14 feet. Thirteen feet, 6 inches is the maximum allowable height for trucks operating without a special permit. 

What causes hoists to raise like that? I figured the driver had probably forgotten to turn off the PTO after delivering a bin. As he got back on the road, the PTO-driven pump repressurized the hydraulic lines leading to the hoist, raising the rails.

I checked this idea with Jim Pigg, a sales rep at Alley-Cassetty Truck Center down in Nashville, Tenn., which specializes in roll-off trucks. He agreed, but added that air or water in a control line may have frozen and prevented the PTO from disengaging.

“That happens sometimes, usually with dump trucks, all over the world,” he said. “It doesn’t happen a lot, but when it does, it can cause problems. The cold can do bad things to machinery.”

A driver can see a raised dump body in his side-view mirrors, but the rails on a roll-off body are out of view. A center rear-view mirror inside the cab, as in a car, would allow a roll-off truck's driver to see through the back window, if he bothers to look at the mirror to see what's happening back there.

Ohio DOT officials got a contractor to the site right away and a crew cut the fallen beam and used a crane to lift it out of the way. They were replacing it and other damaged beams, and most of the bridge’s lanes were reopened by early this week.