MOTT MACDONALD is designing a £137M underground section of the proposed Kallang/Paya Lebar Expressway in Singapore.
Mott was appointed by design and build contractor Samsung Engineering & Construction. The client is Singapore's Land Transport Authority.
Contract 423 is one of the most challenging components of the 12km, six-lane, £450M expressway that will link the East Coast Parkway to the Tampines Expressway in the north of the island.
The section is entirely underground and comprises a 2.9km tunnel, two ventilation buildings, five slip roads, two road bridges and an interchange.
Cut and cover tunnels 36m wide will run below a 27m wide storm water canal whose flow capacity has to be maintained at all times during construction.
Commercial and residential buildings of up to 25 storeys lie along the route, some no more than 3m from the tunnel.
Mott MacDonald will provide detailed design services for the tunnel section. Working from its Singapore office, the consultant will also undertake risk and environmental assessments with specialist support from its UK office.
The appointment follows work carried out by Mott Macdonald during the tender process. The expressway is due for completion by 2005.