The SH20-SH1 Manukau Extension project involves the construction of a new four-lane section of motorway which will connect SH20, at its existing end at the Puhinui interchange, to SH1 just south of Manukau city centre.
The motorway will replace Wiri Station Road as the main link from Manukau city centre to the Southwestern Motorway. The 4.5km long motorway will form the southern end of the Western Ring Route. Construction on the project started in November 2006 with enabling works now underway. The $210m motorway project is scheduled to be completed in December 2010.

SH20 – SH1 Manukau Extension traffic bulletin Transit New Zealand advises motorists that Roscommon Road between Nesdale Avenue and State Highway 20 is closed permanently More
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