Northern Corridor motorway upgrades approved linking South Auckland and Albany

The Northern Busway is to be extended from Constellation to Albany. Photo / File

The last link of Auckland's Western Ring has been given the green light giving motorists another option to get from South Auckland to Albany.

An independent Board of Inquiry appointed to consider an application by the New Zealand Transport Agency today approved the Northern Corridor Improvements proposal.

The new road will create an uninterrupted motorway-to-motorway connection along the Western Ring Route - the Hobsonville, Northwestern and Southwestern Motorways (State Highways 18, 16 and 20) - between Albany and Manukau to the south.

Upper Harbour Highway will be upgraded to a motorway, and the Northern Busway will be extended from Constellation Drive to the Albany park-and-ride station.

The new Northern Interchange has been given the green light. Photo / NZTA

Construction should start in May next year and was expected to talk three and a half years.

The project would include a new motorway ramp bridge from SH1 southbound to SH18 westbound over SH1 and a new direct motorway ramp between SH18 eastbound and SH1 northbound.

Two more motorway lanes would be built for northbound traffic on SH1 between the new connection from SH18 and the Greville Rd Interchange as well as another lane northbound between the Greville Rd interchange and the Oteha Valley interchange and two additional motorway lanes southbound on SH1 between the Greville Rd interchange and the new westbound ramp connection to SH18.

The SH1 motorway crossing Constellation Drive Highway is to be widened by providing one additional northbound lane and widening the bridge over Constellation Drive by one lane each way.

The SH1 motorway and existing bridge crossing at the Greville Rd interchange northbound and southbound would also be widened and the existing bridge over Rosedale Rd is to be widened in both directions. The existing McClymonts Rd overbridge would be replaced with a new bridge south of the existing alignment.

The Northern Busway will be extended from Constellation Bus Station to the
Albany Bus Station. It will be a single lane in each direction on the east side of SH1 and would include a new bridge over SH1 at its northern end to connect to the Albany Bus Station.

It will also require new bridges over Greville Rd, Rosedale Rd and Constellation
Drive. At its southern end it will tie into the existing Constellation Bus Station.

Changes within the Constellation Bus Station include a new platform for northbound buses, extending an existing platform, a new station building and a new pedestrian overpass linking the northbound and southbound platforms;

A shared walking and cycle path will connect to the roads and existing walking and cycle paths on the eastern side of SH1 between the Constellation and Albany bus stations and next to the upgraded portion of SH18 between SH1 and the Albany Highway Interchange.

The existing Paul Matthews Rd connection to SH18 is to be replaced with a bridge over SH18 to connect to the Caribbean Drive/Upper Harbour Highway intersection, which will be a local road and the existing Caribbean Drive/Upper Harbour Highway intersection is to be modified, including providing a connection with adjacent on- and offramps for
the realigned new portion of SH18.