New Ship Channel Bridge
Will Be One for the ​Record Books

Officials settled early on cable-stay, which features two large towers securely anchored to hold up the roadway, which is fused together and tied in places to the cables. The towers bear all the weight.

 

The Harbor Bridge construction, which Harris County officials recently toured, is also cable-stayed. Figg was also the lead designer on that bridge, which like the Ship Channel replacement must cross a vast and active economic corridor.

 

“For something with a span this long, it really is cost-wise the most effective,” said Steve Hague, project manager for the Ship Channel Bridge replacement with HNTB, which the county hired to oversee construction. Like suspension bridges such as the Golden Gate Bridge, cable-stay bridges have a distinctive design and become major parts of the skyline around them.

 

For Harris County, the aesthetic was an add-on, and there are plans to light the towers. But the primary goal was to have four lanes and shoulders for safety.

 

“We definitely want function over form,” Morman said on a recent visit to the construction area. The two massive towers, forming what appears to be a double-X pattern, will dwarf the nearby plants and pipelines. East of Houston’s business district, the only thing taller -- and by less than 55 feet – will be the San Jacinto Monument.

 

In Houston, the bridges will be built separately, starting with the southbound span. That bridge will be completed and traffic moved onto it, so crews can then demolish the existing bridge and build the northbound span.

 

When both are finished in 2024 or 2025, the tollway will be four lanes in each direction with 10-foot shoulders on each side, giving drivers two more lanes and some much-needed breathing room on the sides.

 

“Thank you, Jesus,” Beth Harper, 60, said when told about the shoulders. “It’s terrifying, when there is a truck anywhere near you, to be on that bridge.”

 

In many respects, the spans are a bigger and, officials say, better version of the Fred Hartman Bridge on Texas 146, another cable-stay bridge with two towering columns that carries traffic across the ship channel.

 

The new project goes through one of the most active shipping lanes in the country. It also crosses 106 pipelines, some carrying chemicals so dastardly that specifics were not shared with toll road officials by federal homeland security authorities.

 

Only two pipelines needed to be relocated because of the work. Add to that the fact toll road officials cannot simply shut down the tollway, and the new bridges are shaping to be one of the most complex construction projects ever considered in the Houston area. Yet construction is not expected to significantly slow down drivers.

 

“It is going to take us about a year to get out of the ground,” said John Tyler, the toll road authority’s deputy director and head of its engineering operations. Despite the road and towers cutting an imposing figure along the ship channel, nearly half the concrete for the project will lie underground.

 

To secure the towers in the swampy mud along the ship channel, crews will use 97 concrete shafts poured into the ground, 48 for the southern foundation and 49 for the northern foundation. Just as someone would dig a hole for a fencepost and let the ground do the work of securing the post and keeping it steady, the towers must be solidly grounded.

 

That’s the job of the shafts, some embedded as far as 240 feet into the earth, that will lie beneath a 20-foot-tall concrete pedestal. It is from those that the towers will be constructed out of hollow concrete. “If it was solid, it’d weigh too much,” Tyler said.

 

The project still has plenty of weight, notably in the roadway. The tollway approaching and across the bridge will be made of sections, allowing crews to put the pieces together. Think of it like a giant Lego set made of concrete, held together by wires. The segments, nearly 82 feet wide and 16 feet tall, are nine feet, three inches wide. Building from the two towers, crews will work their way farther from the towers, placing on segment on one side of the tower and then moving to the other side.

 

“You will do one on one side and two on the other,” Tyler said.

 

As they move away from the towers, there will be a total of 584 segments, with 128 of those connected to the wires and then locked to the others. There are eight segments until the next cable is placed. The segments weigh 125 tons each and will be pre-cast at the construction site. Because the pieces must fit and match exactly, connecting pieces will be cast together.

 

The companies have leased vacant land adjacent to the job site where they will stack bridge sections until they are ready for use. Once the southbound bridge is up and ready for traffic in about four years, crews will shift vehicles to the new bridge – divided with two lanes in each direction – and demolish the existing bridge, built in 1982.

 

“Really, in bridge age, it is a teenager,” Tyler said, explaining that officials decided for a total replacement as opposed to building a companion bridge because the current span is simply too narrow for four lanes with shoulders for safety.

 

The current bridge will come down just as the new ones are going up – piece by piece. The bridge, once the longest box-girder bridge in the Western Hemisphere, will be sliced into pieces at the joints where it is built and removed, starting at the points furthest from the pillars supporting it. Crews will then work toward the pillars and eventually remove them. Building the bridges and tearing the current one down is hard enough, but crews will be doing it over one of the busiest shipping lanes in the country.

 

“I don’t think switching the traffic (to the new bridge) is near as complex as the channel,” said lead engineer Mike Perez , senior staff engineer for HCTRA.

 

At points when work is directly above the channel, regulations require ship traffic to cease. For businesses, that could disrupt operations, and make timing critical. Toll authority officials, the contractors, U.S. Army Corps of Engineers, Port of Houston and Houston Pilots Association are all involved in discussions.