How Does Caltrans Plan to Get Construction Vehicles Off the Old Bay Bridge?
The next phase of the Bay Bridge demolition will involve removing these five 504-foot sections, or trusses. (Bryan Goebel/KQED)
As part of our series Bay Curious, we are answering questions from KQED listeners and readers. This one comes from 13-year-old Josiah Raffel-Smith of Richmond.
While traveling across the eastern span of the Bay Bridge recently, he saw a bunch of cranes and construction vehicles. And then this question popped into his head:
How are they going to get construction vehicles off the old Bay Bridge, since it’s not connected at either end anymore?
"I just wondered, are they supposed to bring in big boats to carry them off?" he asked. Or maybe helicopters? Something fun, right?
To find the answer, Caltrans officials take me out to the old bridge. It's a calm, sunny day, a treat they seem to relish because they say it can get quite windy out there.
It's eerie and exciting to be standing on an abandoned structure that was such a centerpiece of Bay Area transportation. The lower deck is much thinner than it once was because crews have ground off several inches of concrete, and my feet feel the vibrations of the construction vehicles rumbling nearby.
"You'd be surprised how much these things vibrated when there was traffic, and you didn't notice because you're in your car with a suspension system," explains Darryl Schram, senior engineer on the Bay Bridge demolition project.
Around us, crews are busy removing pieces of steel and asphalt, preparing the old bridge for the next phase of dismantling. Almost half of the bridge, including the upper deck, has already been removed. Last weekend, in one of the more famous demolition moments, an old pier was imploded in the Bay.
The next phase, beginning in January, will involve removing five 504-foot sections, or trusses. Schram describes them as big trapezoidal boxes.
Each one will pretty much remain intact, but they won't be as heavy. A crane will lower them onto a custom-built barge, which will tug them over to Pier 7 to be cut into smaller pieces.
The bridge is being dismantled from west to east, which brings us back to Josiah's question. How are they going to get the vehicles off when everything is said and done?
It's actually pretty simple.
"We'll just drive them off," Schram says, with a chuckle.
You see, the old bridge is actually connected to a road on the east side. It's a temporary connection that also links to Caltrans' offices on Burma Road. But it's not exactly visible when you're traveling in a car on the new span.
When crews were first demolishing the upper deck, they couldn't get construction vehicles on the bridge. So they had to be craned up from a boat. But now there's an eastern alignment that allows vehicles to travel on and off.
I know, not as exciting as boats or helicopters ... but definitely easier.