A new dual-layered transport corridor for Singapore

The new 21.5km North-South Corridor (NSC) in Singapore is among the most difficult engineering projects in the world right now. Originally planned as an expressway, the NSC was reconceptualised to become Singapore’s longest transit priority corridor and will now include continuous bus lanes saving commuters up to 10-15 minutes. It also accommodates paths for cyclists and pedestrians, supporting Singapore’s ambition to encourage greater active mobility, making public transport healthier, safer and more inclusive. The NSC will run from residential areas in the north of Singapore into the financial heart of the city. Diving beneath the city centre, the tunnel will take traffic beneath majestic modern skyscrapers and traditional street markets, temples, and mosques. Emerging north of the financial capital, vehicles will continue their journey at surface level before moving onto 9km of elevated viaduct. Running in a tunnel for 12.5km means dealing with complex ground conditions and working around existing buildings and infrastructure such as the mass rapid transit (MRT) system. This has demanded world leading solutions never used before, including an innovative application of bridge technology to tunnelling that is now being adopted around the world. Since 2018 Mott MacDonald has been providing a wide range of consultancy services to five of the 11 civils contracts. “This is definitely one of the hardest engineering projects I’ve ever worked on,” says project principal Nick Osborne. The team’s response includes a variety of ingenious and innovative solutions.