Houston is a city of bridges, a web of roads going up, coming down, taking us over and under. They constantly carry different directions of traffic, but there is another constant: the sign on each overpass saying exactly how high it is.

“It is the driver’s responsibility to know the height of their piece of equipment and if it will fit under there,” says Marin Garsee, the director of transportation training at Houston Community College.

HCC boasts the largest public truck-driving school in the country, churning out approximately 1,300 students each year.

“The majority of our students are entry-level truck drivers, so we take them from zero and get ‘em to where they have their license and can go to work for a company,” Garsee says.

An important part of that training is learning how to plan and prepare for a drive.

“We want to make sure a person understands the route that they’re going, the bridge height, the overpass height, any obstacle that could be there,” says Garsee.

Just before 7 a.m. Monday, a truck driver hauling an empty shipping container nailed the Houston Ave. overpass on I-10 eastbound.

The impact ripped the container off the back of the truck. It hit another car, the driver of which is expected to be OK, and shut down several lanes of the busy freeway during the morning commute.

Though the driver was ticketed for an over-height vehicle, investigators are also looking into whether he bypassed an alert system set up by TxDOT along I-10.

Just before the East Loop and West Loop, the agency installed lasers 14 feet up, the height of the lowest bridge.

“When they’re traveling, it starts to flash, gives them the signal to exit now,” says Danny Perez, a spokesman for TxDOT. “But, of course, they have to be paying attention.”

In the end, that’s what it boils down to: drivers paying attention to their load and its limitations.