Betwixt the shores of Germany and Denmark, a massive road and rail tunnel is being built and assembled for positioning under the seafloor.
The marvel of modern engineering will set records; even the facility erected to build it will be an achievement, and the product will dramatically alter the road and rail networks of Northern Europe.
Called the Fehmarnbelt Tunnel, it will span 18 kilometers (11 miles) of water with two double-lane highways, and two rail tunnels. From Hamburg, the journey to Copenhagen will be reduced by half, from 5 hours to just 2.5. From the seashore, a ferry trip that once took 45 minutes will now be a ten-minute drive.
Each 700-foot-long section of the tunnel is as heavy as 10 Eiffel Towers, and there are 79 of them in all, plus another 10 special sections that will house the largest electrical components. They can be manufactured 5 x 1 at a time in an assembly facility as big as 300 football fields on the shore—purpose-built for the project.
When finished, a pair of purpose-built pontoons will utilize 120 miles of steel cables to lower each section into place 40 feet down into a trench dredged on the Baltic Seabed, connected to the other sections, and then buried, making the structure the longest “immersed” undersea tunnel in the world.
Specially engineered gaskets and secondary seals mean that these massive concrete blocks, which by then will have taken 9 weeks to build, can float. After the crews finish installing as many accessory components into each section as possible on land, the sections are positioned in a basin that will be flooded with seawater.
Thus christened, a fleet of tugboats will move them into the grip of the two pontoons for positioning in the sea.
“There will be no test run for the actual immersion,” Denise Juchem, a spokesperson for Femern A/S, the state-owned Danish company in charge of the project, told CNN. “It must work the first time. We will not compromise on quality and safety. That is why we are taking the necessary time to ensure that we are perfectly prepared.”
ENGINEERING THE FUTURE: Giant 2-GW Geothermal Project in Utah Gains Federal Approval
Femern A/S reckon they can lower the pieces into the trench with a precision of 12 millimeters thanks to a suite of underwater cameras.
MORE UNDERSEA MARVELS: Global Project of the Year Turns 1-Hour Car Ride into 5-Minute Journey Along the Seafloor
When finished it will be the “world’s longest immersed tunnel; world’s longest combined road and rail tunnel; the world’s longest underwater tunnel for road; the deepest immersed tunnel with road and rail traffic; and the second deepest concrete immersed tunnel,” the senior project managers claim.
Fehmarnbelt will have a price tag of around $7.4 billion, and is expected to be a boon in both cross-border business and tourism between the countries, which while touching each other, have 12 miles of seawater between the island on which sits Copenhagen and the German mainland.
LOOK AT WHAT WE CAN DO: SpaceX Lands its Rocket On a Dime– So it Can Be Reused and Launched Back into Orbit
As a result, eastern Denmark is especially eager to see the tunnel opened, which will see it seize a justifiable place high amongst the great marvels of undersea engineering.
CHECK out this video explainer from Femern A/S…
SHARE This Triumph Of Human Engineering In Action Today…