The Western Ring Route is a motorway system being constructed in Auckland, New Zealand. It runs along three existing state highways: the Southwestern Motorway (SH20), the Northwestern Motorway (part of SH16) and the Upper Harbour Highway (SH18).[1] When finished it will surpass the Southern Motorway to become the longest motorway in New Zealand at 48 kilometers in length. It will run through Manukau, Waitakere, and the North Shore, bypassing the Auckland city centre and thus providing a second route through the Auckland isthmus.[1][2]
The section of SH20 from Queenstown Road to Richardson Road (the Mount Roskill Extension) opened on 15 May 2009.[3] The section of SH18 connecting the Greenhithe Bridge and SH16 (the Upper Harbour Motorway) and the extension of SH16 to Brigham Creek Road are scheduled for completion in 2012[4] but the SH18 section may open ahead of schedule in April 2011.[5]
Estimated construction costs for the only remaining link not yet under construction, the Waterview Connection, have increased to NZ$1.7 billion, though at times, they were estimated as high as $2.7 billion. As of June 2011, the project was about to receive planning approval.[6][7]
The ring route had been planned as early as the first half of the 20th century. Some critics have alleged that the rerouting of State Highway 1 over the Auckland Harbour Bridge (to ensure toll revenues) has been a primary contributor to the decades-long (and ongoing) delays. The rerouting is thus alleged to have significantly contributed to the need for a massive motorway through the centre of Auckland, severely damaging inner city suburbs like Freemans Bay and Grafton.[8]