From MIT's Technology Review, June 22:
Norway’s Rogfast is an exceptional engineering feat, opening a route for drivers deep below the North Sea. We went down to see it.
It’s cold, it’s very, very noisy, and—if I can be quite honest with you—I’m not feeling super relaxed.
I’m currently around 300 meters, or 1,000 feet, beneath the North Sea, in a dark, dank cave. It smells weird. And I am increasingly aware of the pressure from millions of tons of seawater just above my head, pushing down with a force of more than 500 pounds per square inch. Picture a baby rhino standing on a postage stamp.
Only fabulous engineering is keeping me from being crushed, drowned, disappeared. My safety goggles are foggy.
Just a few hundred meters away, someone is about to blow up a giant rock wall. Luckily, earlier that day I was given a full safety briefing, and I’ve got a special hard hat on. “Don’t worry—if you don’t make it, we’ll have your stuff sent back to your office,” geologist Anne-Merete Gilje tells me, straight-faced. Ah, Norwegian humor.
“It’s kind of a lifestyle. You have to be a little bit crazy to work underground all the time.” —Niclas Brusehed, tunnel foreman, ImpleniaI’m in this odd situation under the iconic fjords of Norway to visit what will soon become the world’s longest and deepest subsea road tunnel, called Rogfast (short for “Rogaland Fixed Link”). I want to understand how you make something as audacious as a 26.7-kilometer (16.6-mile) highway that sits 390 meters (1,280 feet) below the sea at its deepest point. And also—at a time when it can feel hard to get anything done, especially in the US—to reassure myself that ambitious engineering is still possible. That we can still make things.
The Norwegians already have the world’s longest subsea tunnel, the 14.4-kilometer Ryfylke, though Rogfast will dwarf it. Their expertise has attracted attention from Japan, Spain, Morocco, and even a number of US states, whose representatives were due to visit the site in May, just weeks after I went. They, too, want to know how Norway does it.
The answer: tons of explosives.
The entire endeavor feels like an obstinate refusal to give in to physics and geology. “It’s always exciting,” Niclas Brusehed, a tunnel foreman at Implenia, a Swiss firm involved in the project, tells me. “Every blast creates a new world.” There’s not just the blasting of the tunnel itself—although that is an epic project on its own—but an immense logistics challenge involving huge ventilation shafts, extreme pressure, underground roundabouts, and the complex Norwegian geology. Oh, and the water. So much water.
“This is the longest continuous blast on the sea,” says John Olaf Østerhus, assistant project manager at Implenia. “Never been done before. We can’t buy a book to see how we do this.”
All right, time to fish my phone out of my safety suit—don’t want to forget this.
On another planet
Arriving at the rock face where the tunnel hits seabed feels like being on the moon. It’s a huge slab of stone at the end of a long, dark, wet, wide passageway that’s lit (barely) by electric lights. Giant vehicles carting tons of rocks rumble past periodically, and we pull to the side of the road to let them by....
....MUCH MORE
Previously:
September 2, 2018 (via the internet archive, the picture links have rotted):
Infrastructure: "Norway’s $47 Billion Coastal Highway"
[This article was originally published on 22 August 2018. References were corrected on 31 August 2018]
NORWAY'S western coast is home to some of the most dramatic landscapes on earth.
Carved by glaciers throughout the ages, some of these fjords stretch for 200 kilometres inland and are over a kilometre deep.
The current convoluted travel route through and around this terrain takes you along Norway’s 1,100 kilometre, 683 mile, E39 highway - a road with a total journey time of 21 hours.
Now, the Norwegian government are working to improve access to services and residential and labour markets across the country’s western regions by embarking on the largest infrastructure project in the nation’s history.
The E39 runs between, Kristiansand in the far south of the country and Trondheim in the north. The route navigates its way across the fjord network and features no fewer than seven ferry crossings.
The new coastal highway project aims to eliminate the need for ferry services altogether by building a series of bridges and tunnels across, through and under the landscape.
With many of the fjords along the route being too wide or too deep for conventional infrastructure to cross, innovative new solutions are being investigated by the Norwegian Public Roads Administration.
Rogfast is the first in a series of crossings that will link the E39, connecting Stavanger and Haugesund via a 27 kilometre, 16 mile under sea tunnel.
This structure will reach depths of up to 390 metres below sea level, making it the deepest as well as the longest undersea road tunnel in the world.
The Rogfast project will in fact consist of two tunnels connected every 250 metres with emergency exits. Each tunnel will have a lay-by at 500 metre intervals, along with telephone and surveillance cameras along the route.
The tunnel will also feature a mid-route intersection with the island municipality of Kvitsøy creating an undersea tunnel junction and connecting the island with the Norwegian mainland.
With work begun in 2018, this element of the project is set to be completed by 2026 at a cost of USD $2BN.
While the Rogfast works are already underway, the scale of some other fjords is presenting the project team with extreme engineering challenges.
Bjornafjord - located to the south of Bergen - stands 5 kilometres wide, and reaches depths of 600 metres.
To cross this challenging stretch of water, a proposal has been put forward for a floating bridge, anchored to the shore at both ends.
The Sulafjord crossing has seen two possible solutions put forward.
The first is for a three tower suspension bridge, with two of the bridges’ towers anchored on land and the third central tower anchored to the seafloor, some 400 metres below the water line.
An alternative proposal for a “submerged floating tunnel” would see two interconnected tubes running side by side tethered to the seabed using high strength cables.
Crossing the Romsdalsfjord will require a 16 kilometre undersea tunnel, much like the Rogfast project, from Alesund to Midsund - followed by a 2 kilometre suspension bridge connecting onto Molde....MUCH MORE
