The world's longest and deepest undersea road tunnel is under construction in Norway
An ambitious engineering project ‒ the world's longest and deepest undersea road tunnel ‒ is under construction in Norway.
Officially called the Rogfast Fixed Link, the tunnel will extend 16.8 miles, descending to a depth of nearly 1,300 feet below sea level under the Boknafjord in western Norway. Once completed, it will connect the country's E39 highway between Randaberg to the south and Bokn to the north and improve travel times between larger coastal cities like Bergen and Stavanger.
The tunnel, which will also include two of the world's deepest roundabouts, is expected to reduce travel times by 40 minutes and eliminate ferry crossings.
A revised budget from 2020 stated the cost of the tunnel as roughly equivalent to $2.46 billion in U.S. dollars. The Norwegian government is paying for 40% of the project, with the remainder to be financed and recouped through tolls paid by motorists using the tunnel. Those tolls are expected to be around $40, which is roughly the cost of a vehicle ferry from Mortavika to Arsvågen.
Where is the world's deepest road tunnel?
The tunnel will connect an island chain in western Norway's large Boknafjord, with two separate tubes with two lanes each to support bidirectional traffic. The tunnel runs through solid bedrock hundreds of feet below the surface of the fjord.
Near the tunnel's halfway point, there's a 2.6-mile-long spur with the island of Kvitsøy, Norway's smallest municipality. The interchange also includes two roundabouts and maintenance access to two nearby ventilation shafts, one that draws fresh air in, and the other that pushes air out.
The tunnel will be a connection of the European route E39 highway, an 830-mile north-south road through Norway and Denmark.
How deep is the Rogfast tunnel project?
At its deepest, the Rogfast Fixed Link tunnel will reach 1,286 feet below sea level at a point roughly halfway between ventilation shafts at Kvitsøy and Kråga, roughly the equivalent of the Empire State Building.
How safe is the undersea tunnel?
Besides being fortified by hundreds of feet of bedrock, the tunnel is supported by 17 pump stations and 49 electrical substations.
For motorists using the tunnel, there are frequent pull-off lanes for emergencies, 480 emergency call stations, 245 tunnel ventilators and eight shaft ventilators roughly 15 feet in diameter.
Officials have estimated roughly 6,000 vehicles may use the tunnel daily, but predict that number could grow to 13,000 daily vehicles by 2053.
Construction on the tunnel began in 2018 after being approved the previous year. Following a pause in construction in 2019 due to budgetary delays, construction restarted in 2021. The project is slated for completion and opening to traffic in 2033.
SOURCES © Mapcreator.io | © OSM.org, Norconsult/Norwegian Public Roads Administration, New Civil Engineer