Completion of the Auckland Western Ring Route

When completed, the Western Ring Route will be a 48 kilometre motorway offering an alternative to State Highway 1 between Manukau in the south and Albany in the north via State Highways 20, 16 and 18. It will bypass Auckland city to the west and link Manukau,  Auckland, Waitakere and North Shore.

Part of the multi-project ring route is already completed and all other sections bar one will be finished by 2012. The outstanding project is the Waterview Connection, which the Transport Agency announced in mid-May would be a part-surface, part-underground road costing $1.4 billion – half the price of a previous proposal for twin tunnels.

The ring route’s northern section, the State Highway 18 Upper Harbour Motorway, is designed to provide a safe, efficient and high-standard link between North Shore and Waitakere cities. Two of the motorway’s three sections are already in place – the $35 million, 458-metre cantilevered Upper Harbour Bridge duplication (completed in 2006 by Fletcher Construction) and the $110 million, 5.5 kilometre Greenhithe Deviation, a four-lane divided motorway (2006, Downer EDI Works). 

Work on the final section, the $220 million Hobsonville Deviation, began in September last year and is due to be finished in 2012. It is being built by HEB Construction and consists of a six kilometre four-lane motorway from Hobsonville Road to the end of the Upper Harbour Bridge and a three kilometre two-lane extension of the Northwestern Motorway from Hobsonville Road to Brigham Creek Road in Whenuapai. Aurecon is the design engineer, working for HEB, and Opus-Maunsell the engineer’s representative/quality-assurance team, working for the Transport Agency. 

The Hobsonville Deviation will feature five interchanges, five bridges and four roundabouts, will make provision for bus shoulder lanes, and will result in local roads being safer and less congested.

On State Highway 16, road widening is taking place and will be followed by raising the sinking causeway at a total cost of $240 million. The widening includes eight-laning from Waterview-Te Atatu Road (widened to six lanes in the early 1990s) and Rosebank Rd-Te Atatu Road, and six-laning from Te Atatu Rd-Royal Road (a stretch largely built in the 1960s). The widening began in October 2006 and is due to be completed in September next year.

The entire section has been plagued in recent times by traffic congestion at morning and evening peaks, leading to delays and accidents. In alleviating this, the widening will also provide for bus priority during peak travel.

The vital last link in the Western Ring Route, the Waterview Connection, will travel 4.5 kilometres through Avondale and Mt Albert. Although 75 percent of respondents in a local poll had opted for a “minimum disruption” twin-tunnel proposal costing nearly $3 billion, on May 12 the Government deemed that too expensive – a decision that immediately aroused strong public opposition and is expected to cost National votes in the Mt Albert by-election on June 13.  

Next day the Transport Agency announced that the chosen option for the Waterview Connection would be a $1.4 billion mixture of tunnel and surface road. The initial 2.2 kilometres at the southern end will be above ground and part of the tunnel section will be a cut-and-cover trench.  

The project will involve demolishing about 360 homes, nearly half of which the agency has already purchased. The consent process will be fast-tracked and limited to nine months. Construction will begin in 2011 and be completed within four years. A public-private partnership has been ruled out.  

Immediately south of the Waterview Connection is the $201 million four-lane State Highway 20 Mt Roskill Extension, which stretches four kilometres into Mt Roskill from Queenstown Road at Hillsborough. Built by Fulton Hogan, which formed an earthworks alliance with Hurlstone, the extension took four years to construct and opened last month. Six overbridges span this motorway stretch, which will provide considerable relief to local roads.

Project partners with the Transport Agency and Fulton Hogan are Opus International, URS, and Auckland City Council (which has worked with the agency to build a cycleway alongside the extension).

Connecting to the south end of the Mt Roskill Extension is the $230 million Manukau Harbour Crossing between Mangere and Onehunga, begun in late 2007 and scheduled to be completed in time for the 2011 Rugby World Cup. The crossing embraces an area from Queesntown Road in the north to Walmsley Road in the south. It is being delivered by an alliance comprising the Transport Agency, Fletcher Construction, Higgins Contractors and Beca Infrastructure.

The most southern section of the Western Ring Route is the $210 million, 4.5 kilometre State Highway 20 Manukau Extension. This four-lane motorway (with provision for future expansion to six lanes) is being constructed by a joint venture between Leighton Contractors and Downer EDI Works. Project management is being carried out by Maunsell AECOM in association with GHD.

Construction began in mid-2006 and is scheduled for completion in August next year. Features of the project, which has involved nearly one million cubic metres of earthworks, include three interchanges with motorway-to-motorway connections to State Highway 20 and State Highway 1 at Manukau City, and 12 bridges.