Behind the scenes of building new 8-lane span for Howard Frankland Bridge

It is Tampa Bay’s most traveled bridge, and part of it is being replaced. If you have driven over the Howard Frankland recently, you have undoubtedly seen the giant cranes. Construction is happening now to build a brand new eight-lane span of the bridge.

There is a lot going on right now that is vital to the construction that you do not see from the road. FOX 13 News got a behind-the-scenes look at the $864-million project.

The Howard Frankland Bridge replacement is the biggest project the Tampa Bay FDOT Office has ever taken on. Building a bridge across the water is no easy feat.

"Everything has to be built off of barges, which makes construction much more difficult and requires a lot more equipment," explained FDOT’s Resident Engineer, Greg Deese.

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Work on the nearly 4-mile link carrying Interstate 275 across the bay started in November. It is being built from the bottom up. The foundation is created by drilling through a hard rock layer under the bay, then driving concrete and steel piles into the ground.

"The piles can go anywhere from 70 feet to 150 feet, or deeper in some of the locations, depending on where the rock is," Deese said.

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FDOT images

Sensors in the 30-inch square piles ensure they are solid and secure. In all, officials say 43 miles' worth could be used to build the new bridge.

Once all the piles are in place, the next step is to cut them down to the same height, and then crews will pour what is called the pier. This is the sub-structure of the bridge, and work is expected to run through next fall.

"Eventually you’ll see them setting beams and pouring concrete deck and it’ll begin to look like a bridge, slowly but surely," continued Deese.

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It is the first vehicle bridge built across the bay in about 25 years.

The span will become the new southbound bridge, with four general-use lanes, four tolled express lanes, and a 12-foot-wide bike and pedestrian trail. Eventually, the existing southbound lanes will be flipped northbound, and the original bridge from 1959 will be demolished.

"This is going to be a nice improvement, it’s going to extend our express lane system that will ensure that there is consistent travel times throughout Tampa and it will be much better to maintain," Deese said.

The project is on track to finish by the end of 2025.