Motorists get extra lane on Mangere Bridge

Relief is in store next week for motorists sick of queuing to cross Mangere Bridge on their way from the airport to Auckland City.

The Transport Agency intends adding a third northbound traffic lane to the bridge early on Monday, weather permitting, by moving its motorway median barrier eastward and reducing existing lane widths.

That will tie in with motorway improvements on both sides of the bridge to give drivers a three-lane northbound run from Walmsley Rd in Mangere to Hillsborough Rd.

The agency's northern state highways manager, Tommy Parker, is looking forward to providing congestion relief and time savings for drivers - particularly in afternoon travel peaks when homebound workers swell airport-related traffic.

"The bridge with its previous two lanes was a pinch point on the Southwestern [Motorway] that caused a lot of queuing, delays and frustration," he said yesterday.

Adding the extra lane was made possible by the early completion of motorway widening work on both sides of the bridge, as part of the $230 million duplication of the Manukau Harbour crossing.

A duplicate four-lane motorway bridge on the eastern side of the existing structure is expected to open for traffic in late June or early July before the overall completion of the project in August - seven months ahead of schedule.

Although the new bridge will eventually be used entirely by southbound traffic, some vehicles heading towards Auckland may get to use it briefly to allow the existing structure to be resurfaced and its median barrier to be removed.

The existing bridge will from August offer four lanes for the exclusive use of northbound vehicles.

Mr Parker said that because the northbound lane widths were being reduced temporarily on the bridge from next week, it was important for drivers to observe an 80km/h speed limit, which would be restored to 100km/h once the project was completed.

If wet weather hindered contractors in their preparations for their changeover, the opening of the third lane would be delayed until next week.

Airport company spokesman Richard Llewellyn welcomed the extra lane capacity as offering another incremental improvement in journey times to and from central Auckland.

A consultants' report in 2005 drawing on information from bus-mounted GPS tracking systems highlighted a wide variation in travel times between the airport and central Auckland, from 19 minutes to 47 minutes northbound and from 16.5 minutes to 36.5 minutes in the opposite direction.

But Mr Llewellyn said the Mt Roskill motorway extension, which opened last year, combined with the more recent motorway widening along Onehunga Bay had largely cleared northbound traffic congestion on the Auckland side of Manukau Harbour.