Aecom joint venture wins detailed design deal on Sydney’s $2.9bn Western Harbour Tunnel

Stage 2 alignment of the Western Harbour Tunnel, subject to detailed design (Image: New South Wales government)

A joint venture led by infrastructure consultant Aecom has won a contract to develop the detailed design of the Western Harbour Tunnel in Sydney, Australia.

The award comes after Acciona Construction Australia won an AU$4.24 billion (US$2.9 billion) contract late last year to deliver stage two of the tunnel.

The 6.5km-long tunnel will have three lanes in each direction and will provide a western bypass of the central business district, reducing traffic on the Sydney Harbour Bridge, Sydney Harbour Tunnel and Anzac Bridge.

Aecom said that following acceptance of an alternative client reference design, the Aecom joint venture, called Aurecon, would deliver a detailed design that avoids dredging by utilizing tunnel boring machines instead of an immersed tube tunnel.

Richard Barrett, chief executive of Aecom’s Australia and New Zealand region, said, “The improved design and construction method is an excellent example of industry collaboration and is expected to deliver significant reductions to the amount of steel and concrete required, as well as other environmental benefits, compared to the original reference design.

“Importantly, the new Western Harbour Tunnel will help the region better meet the demands of its growing population by reducing congestion while also reducing the impact on the harbour.”