Auckland road project gets $100m upgrade

Waterview Interchange and Waterview Connection Tunnel development towards the Causeway, on the Northwestern Motorway. Photo / Brett Phibbs

Funding allocated for three lanes and bus shoulder between Henderson and Westgate

Government road builders in the thick of the country's largest transport upgrade are designing yet another project for Auckland's western ring route.

The Transport Agency said yesterday that a $2.2 billion funding allocation to complete the long-awaited alternative route around the Super City, between Manukau and Albany, will provide for a $100 million upgrade of the Northwestern Motorway beyond Henderson. That will provide three traffic lanes and a bus shoulder in each direction to Westgate.

The agency is already spending $500 million widening a 10km stretch from the St Lukes Rd interchange at Western Springs to Lincoln Rd - almost half of which involves expanding and building up a causeway which has been sinking into marine sediment since 1952 - as well as $1.4 billion on the half-tunnelled 4.8km Waterview Connection.

Other costs include an upgrade to the Maioro motorway interchange in New Windsor, south of the two Waterview tunnels.

But the Government has made a separate allocation of about $450 million for a motorway-to-motorway connection between the 47km ring route and State Highway 1 north of Constellation Drive, to be completed by 2021.

Work on the causeway requires a delicate balancing act to line up old and new parts of the structure without causing too much extra settlement under almost a million tonnes of fill and pavement. The causeway is being widened to carry five lanes of westbound traffic, a bus shoulder, and a shared cycling and walking path between Waterview and Rosebank Rd, and four traffic lanes beyond there and in the opposite direction.

Labour transport spokesman Phil Twyford acknowledged that the completed project will provide faster trips on buses, giving them their own space on two causeway bridges including across the Whau River.

But he was disappointed provision was not made for a separate busway.