HAMPTON ROADS, Va. (WAVY) — It is one of the greatest engineering marvels and for many years the Chesapeake Bay Bridge-Tunnel was the longest bridge-tunnel in the world. Today it takes on new life in the form of a new tunnel.
“They’re driving on a beltway,” said Mike Crist, executive director of infrastructure for the Chesapeake Bay Bridge-Tunnel.
Unlike previous projects, they use a tunnel boring machine (TBM) named Chessie to dig a tunnel.
“Almost all the tunnels in the area were built using the submerged tube tunnel method,” Crist said, “so they built 300-foot-long tunnel segments in a dry dock, they floated them here , dug a trench, submerged them in a trench, and then covered it. In this case, we start digging a tunnel under the canal and build the tunnel as we go.
Chessie has a cutting head 43 feet in diameter and is approximately 300 feet long, the length of a football field.
As the drilling progresses, these pieces of concrete are placed inside the tunnel to create rings.
“Ten segments make a ring, there are 990 rings in the tunnel, so in total we have 9,990 segments,” Crist said.
And as the segments are placed, Chessie runs a “mud,” returning that mud from the tunnel – clay and sand – to the shore.
“It’s excavating the soil and the water, and it will go down to the bottom of the chamber and put it on the conveyor belt and bring it out,” Crist said.
Construction began in 2017 and operation of the tunnel began in February 2023, but they hit a roadblock a few months later when they hit the anchor of a historic ship.
Construction of Thimble Shoal parallel tunnel halted after underwater discovery
And a few months later, the anchors had fallen off as they moved forward on the project.
The new tunnel will ultimately parallel the existing tunnel from the southernmost island, closest to Virginia Beach, approximately 70 feet underwater to the second island. You can also say goodbye to head-on traffic in the tunnel, at least for part of your journey.
“This is the area where we get our biggest traffic backups, so this should alleviate some of that problem,” said Tom Anderson, deputy executive director of finance and operations. “Of course, this won’t be fully mitigated until we are able to tackle the other Chesapeake Channel checkpoint.”
The project is funded entirely by tolls and toll bonds, as CBBT does not receive any local, state or federal money. That’s why Anderson said they’ll have to save up before starting the next one.
In the meantime, they ask you to be careful when crossing this summer.
“There’s a lot of lane changes, there’s a lot of construction activity, a lot of dump trucks and tractor-trailers going in and out of this particular island,” Anderson said, “so drivers have to be pay attention to this.”
At this point, the tunnel is approximately 25% complete as far as drilling is concerned, but there is still work to be done once drilling is complete. Much of the project work is taking place on or around the two artificial islands.
“By the end of the year, we hope to have the tunnel built all the way to the second island,” Crist said, “so that all 6,400 feet of tunnel will be completed, and then the workers will remove the tunnel boring machine and they “I will come back and start building the road bed, installing the utilities, the ventilation equipment and building it up so we can drive on it.
Currently, the entire tunnel project is expected to be completed by August 2027.
For the latest news, weather, sports and streaming videos, visit WAVY.com.
yahoo
