London rail project presents some watery challenges
Designing a rail station 18 metres underwater presented significant challenges, but this transport-oriented development has created a new destination for Londoners, says Arup’s Mike King.
Europe’s biggest underground civil engineering project, Crossrail, is currently being constructed under central London. Once complete in 2019, it will increase central London’s rail capacity by 10 per cent, with up to 24 trains per hour running in each direction during peak times.
The new Canary Wharf station, sitting below a five-storey retail and leisure development known as Crossrail Place, connects a key business district to the City of London, the West End and Heathrow.
Arup’s involvement in the project extends back to the early 1990s, when Crossrail was proposed by British Rail and London Underground. Since then, Arup has worked on a number of new station developments – both above and below ground – as well as remodelling existing stations.
King, Arup’s principal in Australia, says finding a suitable location for the Canary Wharf station proved challenging, and “it got even trickier when the answer came in the shape of part of an existing dock”.
This meant designing a 60,000 sqm building surrounded by water. The solution was “a fully submerged station with shops, restaurants and a new 30 sqm public garden above the waerline”.
From the outside, Crossrail Place is a “ship-like structure topped with one of the world’s largest continuous timber roofs”. Below this are four floors of retail, leisure and restaurant space.
Crossrail Place was designed to be flexible even after construction was completed.
“If the retail levels are no longer needed in the future they can be removed completely and the station will remain fully functional,” King explains.
“Alternatively, if the retail area needs to be overhauled, it can be reconfigured. Multi-functional spaces can be easily adapted to provide retail or restaurant uses, even a multi-screen cinema. Within each unit, the tenant has flexibility to have double-height spaces, lifts and stairs, or add mezzanine floors.”
King says this was essential for the long-term commercial viability of a project where the rail infrastructure is designed to last 100 years, while the life of the retail and leisure fitouts above it may be as low as five to 10 years.
To minimise noise disruption during construction for nearby occupants, including four major bank headquarters, Japanese Gikem piling technology was employed for the first time in the UK, using hydraulic pressure rather than impact to drive the piles. These interlocking steel piles formed a watertight perimeter wall after which the dock water was drained and the station was built inside the walls.
This ‘silent’ piling method shaved a year off the program and produced substantial cost savings.
Creating a ‘destination’ three years before the station opened presented another challenge – and the key, King says, is to create “compelling places for people to experience.”
A 200-metre-long landscape roof garden, containing plants from around the world, is connected with meandering paths that lead to a performance amphitheatre.
“The architecture and public garden attract visitors and raise the cultural profile of an area known more as a relatively ‘sterile’ business centre.
“The public garden, the retail, entertainment and food and beverage elements make the Canary Wharf area a more attractive destination for people to spend their leisure time, rather than just their work time. It enlivens the area in non-working hours and weekends, when it might otherwise be something of a ghost town.”
Mike King will be sharing further insights into ‘World’s Best Projects’ at The Property Congress from 20-22 October 2016. More than 6 delegates will attend this year’s SOLD OUT event. www.thepropertycongress.com.au