Norway is Building The World's Deepest Mega-Tunnel

Europe is transforming how people travel across the continent in one of the biggest building sprees in history. A new mega hub. Tunnels running through mountains. Railways realigning entire countries. But there's one project that's breaking a record so big, it's pushing construction to its absolute limits. And it's happening right here beneath my feet. — This is the west coast of Norway, a place of impeccable natural beauty, vast fjords formed of huge mountains and deep seas. But it's also home to heavy industry, the engine of the country's economy. And when a force as big as that meets a landscape as wild as this, it's up to construction to find a solution. The answer is to go deeper and further than anyone has ever gone before. If — you had to describe this project in a single word, what would you say? — Big. — The p is about 6 700 m deep. — 600 m deep. — Yeah. — Wow. — Are you afraid? No. That is millions of years worth of history. It's sitting there untouched, undisturbed, pretty much since its creation. And then suddenly the jumbo drill arrives, starts drilling it, marking it up, revealing it to the world for the first time. How can you not love construction? When you see stuff like this, — it's insane what we're doing. — This is the holy grail. It is so cool. Hello from the Norwegian city of Stanganger. Now, to give you an idea of

why this is just about one of the hardest places on the planet to be a civil engineer, I'm going to post a letter. The first postal routes along the west coast of Norway was established in 1647, carrying mail from Bergen to Tronheim without having to be routed through the capital Oslo. If you know anything about Norway, you'll have heard about its fields. These massive valleys that splinter the country's coastline. That journey along the male route was not for the faint-hearted. Norway's first postmaster, Henrik Moran, was a grizzled adventurer who'd find himself rowing across vast water only to be faced with a 1,500 m vertical climb once he got to the shore. And then there was the weather. Snow and ice frequently made entire stretches of the route completely impossible. Despite the terrain, the pathway kind of stuck and over the centuries developed into this, the E39 highway. Today, it takes you from Tronheim in the north down to Christian Sand in the south where a ferry carries you into Denmark and then the rest of Europe. Now obviously today we have cars rather than pack horses and rowboats but it's still an absolutely epic journey. It takes about 21 hours to drive this 1100 km route and along the way you have to take nine fairies more than any other single road in Europe. At this point you're probably thinking well Norway is a wealthy country why don't they just build around it? Well, they have. Since the 1990s, Staten's Veess, the Norwegian Public Roads Administration, has been improving infrastructure along this route with numerous suspension bridges and over 30 tunnels, each one over a kilometer long. But there's just so much to do. There's over a thousand fjords along Norway's coastline. And with each one being unique, there can't be a standard approach. Some fields have got narrow, steep walls, while others are wide and shallow. Both of which present huge challenges for completely different reasons when it comes to designing a bridge. And tunneling is hardly an easy alternative. It's not like just crossing a river. In many fields, the valley walls extend further beneath the water line than above. It's only when you get here and stand among these landscapes that it really hits home just what these construction teams are up against. This is leiser fjords and like all of Norway's fjords, it was carved out by massive glass at the end of the last ice age. These huge mountains you see around me actually extend for a long distance beneath the water's surface. Over the years, Norway has managed to cross many of its fjords, but the ones that are left now, the ones it hasn't crossed, are among the biggest and most challenging in the entire country. And to solve that, they're now turning to ever more ingenious and daring solutions like this one at Sula Fjordan. It's one of many places along the E39 where you

have to park up and wait for a ferry. Steep cliffs surround the narrowest point of the shoreline. So the ferry has to run from the low-lying land here. But at 7. 5 km, that's far too long to cross with a bridge. If you were to take the world's longest suspension bridge, Shinaclay in Turkey, it would take you to here. And then there's the depth. Now for comparison, the English Channel that separates Britain from France is about 60 m deep on average and 174 m at its very deepest point. But the seabed of Sula Fjordan lies up to 400 m below the surface. It's too narrow and too deep for a standard tunnel, which is why this was suggested. a new crossing further up the coast featuring a floating tunnel tethered to the seabed suspended just beneath the surface of the water. The only problem is that nothing like that has ever been tried anywhere before. So, another idea is also under consideration. A multis-pan suspension bridge with a tower on each shore and a third in the middle anchored to the seabed by huge concrete columns. I've spent years covering massive projects like this, and their immense scale never ceases to amaze me. But what's genuinely harder to convey is the smaller day-to-day, more granular level of decision-m that, to be honest with you, is really the key to making mega builds like this successful. But the way teams manage that complexity is about to go through a generational shift thanks to Procore. Now, I know there are going to be contractors watching this who can see AI coming down the track, but look out at the mud, dust, and organized chaos of a construction site, and kind of struggle to see how it can make much difference. You've got multiple teams working in different locations, hundreds of deliveries to land on a single day, and margins that are so wafer thin, any mistake is going to cost you big time. But that's exactly the kind of complexity that Procore AI is built to take on. Think of it like having a right-hand man, someone with you who grew up on the job site, who's seen every mistake and knows every trick of the trade. To see how Procore AI can help your next project, scan the QR code on screen or click the link below. Now, let's get back to that epic tunnel project. If this project so far feels a little bit extreme, just know that it is nothing compared to what's going on further down south in one of the most important areas of the country. This is

Boknner Fjord. One of the largest fjords in all of Norway. This thing is enormous. 20 km wide at its mouth, stretching for 45 km in land and hundreds of meters deep. But this place is much more than just a beauty spot. Back there behind me is Stanganger where I start my journey. Up the coast there is Bergen. This whole region is home to three pretty fundamental pillars of the Norwegian economy. fishing, oil, and natural gas altogether making up more than 20% of this nation's GDP, which is a problem because at the moment everything has to pass through here. And right now that involves driving through a tunnel, across an island, then a bridge, and into another tunnel, another island, and finally a ferry. For such a critical highway, it's just not good enough. There are more than twice the amount of trucks using these roads as elsewhere in Norway, and that number is only increasing. But the roads are narrow or single lane, and these tunnels are often closed due to accidents. Wouldn't it be nicer to have one big tunnel from one end to the other? Well, yes. And to do that, the only way is down.

We're building this tunnel to connect the land on the both sides of this short and we're also building it towards this little islands so that we can skip the ferry from there and also get the fairies away from the European highway that goes along the coast. of Norway. — This is the Roggerand fixed link or Rogfast tunnel, a Twin Tunnel running 27 km across the mighty Boknaffort. Construction is taking place simultaneously across three separate sites. Here, the southern tunnel extending north from Norway's oil capital, Stvanga. Here, the northern leg where the tunnel is going to borrow to its deepest point. And finally, here at Kavitzoy, the most complex part of the project, where a 200 m deep multilevel interchange extends in both directions across four rock faces at 26. 7 km long and 388 m at its deepest point. It'll be the longest and deepest SubC road tunnel in the world. With construction crews facing such a mammoth challenge to make this happen, one question springs to mind. Why on earth are we doing this here? — It's the best place we could put it. It's quite deep uh further in the fjord and there's like this ridge at the outer parts of it. So, we're following that ridge so we don't have to go as deep as we would have had to go if we were further in the fjord, — right? — Cuz the fjord is about 600 700 m deep. — 600 m deep. — Yeah. — And out here it's only like 370. — Okay. So, so we only have to go through about almost 400 meters deep at the lowest point of this tunnel. — The scale of this tunnel really does give you a sense of how immense the fjord is above my head. I've been walking through here now for 6 and 12 km and it's just still going and it all looks the same. It's just the same thing for mile after mile. Up there ahead of me is the drilling face where they're kind of making progress extending this tunnel bit by bit. This tunnel is going to be sitting 390 m beneath the waves of the fjord above my head. To put that in context for you, you could fit the Empire State Building between the top of my helmet here and the surface of the fjord above. — What's the hardest part of building this

tunnel? What have you found the most challenging part of making this project happen? I think it's it is the geology. It's the uncertainty of the geology because that's what can sort of uh destroy the whole project. Okay, so it's time for a quick geology lesson. Those same massive forces that created the stunning mountains above ground have left Norway with a very unique inheritance down below ground. Across its length, the tunnel passes through several distinct bands of rock between which lie fault zones where rock has been crushed and fractured by millions of years of geological movement, creating some of the most unstable and unpredictable ground on the entire route. Each rock band has different properties. Some, like phite at the southern end, are dense and tight, making it easier to navigate but useless as a road material. Others like Nice further north are riddled with cracks that hold enormous quantities of highly pressurized water, making this stretch one of the most unpredictable and quite frankly wetest sections of the entire build. — So like last week, we had a really big breakthrough here. It was like between 5,000 6,000 uh liters per minute. — Wo. — It was a bit more than just a garden hose. We're talking like — it's a bit more than water leak it. Yes. — And in this kind of situation we are um 330 m below the sea level. — Wow. — So the pressure of the water it's like 33 bars. — Wow. — When it's open cracks it will just come in like that and blow into the tunnel here. We are prepared for these kinds of incidents. So u we have huge pumping gears and so on that it's easy to put out and to get the hold of a situation. That chronic unpredictability means that building a tunnel in Norway is unlike building one anywhere else on Earth which naturally calls for a bit of a different approach. Now if you've watched our videos before you might be wondering where the TBM is. And sorry to disappoint you but on this project there isn't one. Basically, a load of different factors go into choosing the specific type of tunneling method you're going to use on your project. And here, it's all down to the rock. Rather than relying on TBMs, decades of tunneling through this fractured and

unstable landscape has seen Norway develop its own specialist type of excavation, the Norwegian tunneling method. And it all starts with one of these. This huge kind of yellow and black spider you can see sat in the cave with me here is actually called a drill jumbo. It's an incredible name. No fewer than four massive mechanical arms coming off of it pushing drill bits into this rock face in front of me. This here is the front line of Rockfast tunnel construction. Each of those robotic arms is controlled from a system up here in the cab. Let's go have a look. So, this is where the action happens, right? This is the cab of the drill jumbo. It looks like some kind of Nintendo Switch system, right? There's a big chair, control system, there's joysticks, the screens. This is where they control the drills. The power that you could have sitting here. Once a professional takes charge, the jumbo drills 15 m holes in the rock to test for water and rock stability. Before the face can be blasted out, a protective shield needs to be formed around the excavation area inside the rock. And that's done with this beast. Forget your bathroom renovation. This is the most sophisticated grouting machine you will ever see. Developed in Norway, it creates a waterproof seal inside the face to allow rock to be blasted out without causing water to flood in. These tanks under constant resupply contain around 2. 5 tons of micro cement ground to around 25 microns. Once the machine's in action, this is transferred to an agitator where a computer blends a precise mix of micro cement, super plasticizer, water, and slurried silica fumes. That mix then gets blasted into the rock face with around 100 bars of pressure at a rate of some 20 L per minute. Depending on the rock formation, each operation can take between five and 75 tons of grout to complete. Once that grout has set, it's back over to the jumbo to set the route. Now, with no GPS available, surveyors use laserg guided total stations to mark a grid of holes on the rock surface. Inside the jumbo cab, an operator uses information fed from the total station to line up the theoretical position of the grid with the actual position of the jumbo arms. These enormous limbs drill holes 5 m deep into the rock face, which are then packed with explosives. With the tunnel cleared, there's just one thing left to do. It's skilled, sophisticated work which involves constant checks to see how the rock is reacting. going through these large subsidy tunnels with the uncertainty in the geology it would be too risky to go with a TBM because like TBM is a very large machine it's several hundred meters long and as you can see this is a very small machine doing the drilling from us so if we have a water leakage or any problems it's very easy to go back and start doing things in the face and if you have a TBM and you it's like your 100 m long machine you have to move out and start doing things it's much more flexible to use the drill and blast for this kind of rock and this kind of projects. — So with those different rock types you were talking about with drill and blast you can sort of — see each different scenario as you go and respond to it with different techniques you were talking about. — Yeah, we have geologists coming in every time we blast every fifth meter doing mapping of the structures and of the geology and then saying what kind of rock support should there be and also saying what should we do for the next blast. After each blast, rubble is taken out and the excavated area is covered in a waterproof membrane and sprayed with shockrete. Reinforcing bolts are then drilled into the wall to prevent the rock from deforming. Finally, the tunnel is lined with concrete panels. These are just some of the 60,000 individually designed panels that are going to be used to complete the tunnel. It's painstaking work with each cycle ekking out around 5 m at a time. And that's the heart of this project. day in day out for just a few meters each time until you've built a tunnel that runs for several kilometers. And don't forget, there are two of these. Just through those rocks there is another tunnel running parallel to this one. Now, it might look simple, but there's actually a heck of a lot more to building a tunnel than just blasting through some rocks. Now, when you're in a tunnel, there are going to be a few things you need, like

lighting, rescue points, and evacuation routes. But there's something else that's far more essential. All tunnels, even short ground level ones, need to keep air circulating. The longer and deeper you go, the more help your tunnel needs. Rogfast is being equipped with 245 jet fans to keep things moving, as well as ventilation towers at both shorelines to create more air flow. But for a tunnel this long, even that's not enough. Which is where this place comes in. the island of Kavitzoy. It's pretty much slap bang in the middle of the route, which is why it's now home to a huge new feature. Wow. Take a look at this. That is crazy. Work is currently underway on two huge ventilation shafts bringing the fresh kavet soy air deep down into the tunnel. So I'm currently standing deep beneath the island of Kavitzoy in the middle of Norway or under Norway I should say at the bottom of the completed one of those ventilation shafts. This is the one they finished already. It is absolutely enormous. You could easily fit a skyscraper in here. To build these vital lifelines, a pilot hole was drilled from the surface downwards. Next, a drill bit 2. 5 m in diameter was dragged up through the rock over the course of 3 weeks. From there, the same drill and blast method as before was adopted. A 9. 5 m wide hole is blasted and soil is shoveled down the pilot hole for excavation from the bottom. The shaft wall is cleared, lined with shockret, and reinforced with bolts. After initial work is complete, a housing is built over the shaft and crews are lowered down by a hoist to complete the work for another 200 m. Look at that. There's a little tiny slither of light above me. That is daylight. It's one of those things again that when we use tunnels every day, you don't think about the fact you can breathe. ventilation. But it's feats of engineering like this, things like this that no one's ever going to see that make this whole tunnel viable. Kavitzoy really does play a critical role in allowing this tunnel to exist. And fortunately for Kavitzoy, that favor is being returned. So I have filmed in countless tunnel construction sites. I have filmed

countless tunnel junctions, junctions sitting below the earth. I have never in my life seen a road network this complicated underground. It is insane. There are routes going off in all directions. There's a freaking underground roundabout here. Car going around it right now. Nice little demonstration for you. This is the jewel in the crown of the Rockfast tunnel. The Kavitzoy interchange. Above the island of Kavitzoy, population 500. 250 m beneath that is the most complex subca interchange ever built and home to a world first. Driving north, traffic heads off via a slip road and begins to negotiate the deepest road junction on Earth. Here the road climbs to meet the first of two roundabouts which directs Kavitz soybound vehicles into a link tunnel. A bridge carrying traffic over the main tunnels below. From there, traffic joins the southbound roundabout where another slip road climbs 4. 1 kilometers up to the island. As if all of that wasn't enough, threaded between everything are access tunnels, cross passages, and those enormous ventilation shafts we saw earlier. This whole area is like a like being in some kind of big underground rabbit warrant. So here you've got those two tunnels going each direction, meeting spurring off, meeting two different roundabouts, hitting a ring road going up onto Kavitzoy. You've got two massive ventilation shafts and the kind of enormous ducks if you like going off to those ventilation shafts. When you think about a tunnel, you think of a long straight tube under the ground. Here is where they take like seven or eight of those tubes, more like nine or 10 of those tubes and wrangle them all up in a big pile of spaghetti, yet still know exactly what's going on. The entire Rockfast tunnel project is incredible, but it's this bit that is particularly astonishing. This is where you feel the full magnitude and the epicness of the feet of engineering. There are no fewer than eight different tunnel faces being worked on around here as they build off in all kinds of different directions. is as someone who loves construction, who is fascinated by what makes these things work, by the stuff that we take for granted when we go through these places. This is the holy grail. It is so cool. But this isn't just a little detour. It's actually the most technically complex part of the entire route. So why the hell are they building it? Well, obviously with the ventilation shafts here, it's beneficial to the construction teams to have an access route back up to the surface, but it's actually about a whole lot more than that. In Norway, when new roads are proposed, this isn't just some design decision that's taken over in Oslo and then imposed on a local community. Instead, road administrations in the Norwegian government put forward suggestions for new roads and the local community are invited to give feedback, suggestions, and make improvements for what's being put forward. And that's exactly what's happened here. Kavit Soy got a critical new connection down onto that major artery of a new tunnel running through this region. But it's also getting 1. 2 km of new land reclaimed from the sea using rock from that tunnel construction. And long before anything happened down there up on ground, the construction teams here were upgrading roads and even constructed four new bridges. I guess the important thing to take from all of this is an appreciation of the fact that yes, by building a better connection through this part of the nation, Norway as a whole is going to benefit, but there's also a lot of benefits coming to local communities as well. So this last part of the tunnel I've come to see is the EO3 site which

connects the southern side of the fjord back to Stanganger. Being down in these tunnels is like being in some kind of eerie subterranean world. It might look quite simple at first, but look a little closer and you see there's actually all kinds of attention to detail. There's temporary lights all on the wall so you know where you're going. There's these huge inflated temporary air ducts in the ceiling that bring oxygen down here so we can work so crews can work and get this tunnel built. Down there is the drilling face. That is as far as this undersea tunnel has gone right now. That is the frontier they're fighting against this whole time. And this here is something very unusual that you don't see on many sites. Because we're in Norway, a lot of the big construction plant here is electrified, which is great, but they can't have batteries down in the tunnel. So, what you need is basically the world's biggest extension leads to bring power down from the surface here. Think of this as like your household extension leads. And that machine is then plugged into that. It's Yeah. little quirk of a Norwegian subc tunnel site. What's it like working down here every day? Ah, it's a lot going on here. Uh, really? — And you're saying behind us say this is the workshop. Yes, — exactly. — We're basically repairing vehicles so they don't have to go back up to the surface to get fixed, right? — Yes. So, when we are working on the face, we have uh like uh we want to do it the most efficient way. — And you were saying this workshop it moves with the project, right? — Yes, that's correct. So every 1500 m we are like uh moving the workshop further down to the tunnel and uh then to make sure that the traveling time between the workshop and the phase are as close as possible so that you don't have to drive back and forth the whole time. — What are you proudest of so far? — The guys down here that working and uh doing the work every day in the in the darkness and then don't see the sunlight every day. So, I'm really proud of the people. They're doing it in a safe and efficient way. And uh yeah, they're really good at what they do. For thousands of years, life in Norway

has been shaped and dictated by the water. Getting on here, building a civilization here has always meant negotiating a truce with the natural world. And it's kind of easy to think when you see this tunnel project that they're trying to shortcut all that. But that really is to misunderstand this project. To construct this incredible feat of engineering requires a really special kind of negotiation with nature. Here every single step of construction matters. A millimeter carries just as much weight as a kilometer. Not far from here is the Ryfast tunnel that currently holds the world record for the longest and deepest undersea road tunnel. Many of the same people who we've met on this trip worked on that tunnel and are now working on the Rogfast tunnel. They're breaking new frontiers. They're setting new records. And while it all may sound very impressive, ultimately what they're doing is setting the bar for when the next team come in and build something even bigger and better. Oh, return to sender. This video was sponsored by Procore. Don't forget that you can learn more about how Procore AI can help out your next project by scanning the QR code on screen or clicking the link below. And as always guys, if you enjoyed this video, which you obviously did because you made it this far through, and if you want to get more from the definitive video channel for construction, the channel that actually takes you down into the world's deepest undersea road tunnels for some record-breaking footage, make sure you hit that subscribe button.