SKM was engaged by Leighton-Works as the Lead Design Consultant for this Design & Construct project for the New Zealand Transport Agency (NZTA) to provide engineering services for the tender and detailed design phases of the SH20 Manukau Extension Project from July 2006 until the new Motorway link opens in June 2010.
The 5.5km motorway links the existing SH1 Southern Motorway at Manukau City to the existing SH20 Motorway at Puhinui, in Auckland. The NZ$210m project is a key part of the strategic Western Ring Route (WRR) in Auckland. The completed WRR will provide an alternative to SH1 by bypassing the city to the west and linking Manukau, Auckland, Waitakere and North Shore Cities. Completion of the WRR is a high priority for NZTA. The project will improve access to and from Auckland International Airport; provide considerable relief to local roads within Manukau City Centre; and aid the future growth at the Wiri and Auckland International Airport business zones.
The work undertaken by SKM included the design of roadworks; 14 bridges; 3 grade separated interchanges; design of local roads; drainage infrastructure; complex traffic modelling; and design support during construction.