KEY POINTS:
Almost 30,000 vehicles are expected to pour daily along a new road which opens tomorrow between Auckland's Southern Motorway and a $1 billion business park being developed in East Tamaki.
The new arterial, a 2.5km extension of Highbrook Drive hailed as the long-awaited "front-door" for industrialised East Tamaki
and its booming residential hinterland of Flat Bush and Dannemora, joins the Southern Motorway at an interchange Transit NZ has built just north of Otara.
Manukau City Council has built a 210m bridge across the mouth of Otara Creek to carry the four-lane road, which it has constructed with Highbrook Development, an Australian-New Zealand partnership establishing a business park on a scale said to be larger than anything on either side of the Tasman.
For Manukau Mayor Sir Barry Curtis, the road is the culmination of years of lobbying to ensure better access to Auckland's fastest-growing employment area through the picturesque Waiouru Peninsula.
Highbrook's 193ha site is being developed to a landscape masterplan by American designer Peter Walker, which provides for 107ha of buildings and a 40ha park already open to the public around the peninsula's 12km coastline and one of Auckland's oldest volcanic craters - Pukekiwiriki.
Traffic, much of it commercial, has until now had to crawl along East Tamaki Rd or through Mt Wellington to reach the motorway.
The project, which also involved widening the motorway and moving the off-ramp to Otahuhu northwards to create a safer distance from the Highbrook interchange for drivers joining or leaving the main traffic flow, has been completed within its $74 million budget. The Government contributed $44 million, Manukau City $22 million and Highbrook Development $8.2 million.
Although traffic engineers predict early flows along the new road of 29,400 vehicles a day, they believe most will remain on the local network, and that motorway volumes between the new interchange and Otahuhu will rise by little more than 6000 - to 121,000.
Transit believes auxiliary lanes added to each side of the motorway to increase its width to eight lanes along that section will absorb much of the extra traffic for now, although a claim on the developer's website that it will take just 15 minutes to commute between Highbrook and central Auckland is considered over-optimistic.
A roundabout east of the interchange will offer drivers a more direct route to central Otara or the Bairds Rd bridge over the motor-way to Gt South Rd and the airport.
Highbrook Drive is expected to siphon up to 14,000 vehicles a day off East Tamaki Rd, and to offer varying levels of congestion relief to other overloaded local routes.
Daily traffic volumes along the new road are forecast to rise to almost 36,000 in four years, and the Manukau council says it will be capable of carrying up to 50,000.
Although bus services have yet to be arranged for the new road, a footpath-cycleway has been built along the seaward side of the motorway between Otahuhu and Highbrook.
Greenmount East Tamaki Business Association president Elspeth Mount said pushing for a direct route to the motorway was a fundamental goal of her organisation when it was founded 13 years ago.
Although grateful for the project's completion, she believed that traffic projections could prove conservative, and that the Manukau council might have to accelerate improvementsto roads feeding commuters into Highbrook Drive from as far awayas Beachlands and Maraetai.
Botany Community Board chairman Michael Williams said that although the new road would offer short-term congestion relief by taking trucks off key commuting routes such as Ti Rakau Drive, a predicted population growth of 40,000 people for Flat Bush in under 10 years demanded urgent action to improve other links across the Tamaki River.
Despite the scepticism over the 15-minute commuting claim, the fact that key logistics firms such as DHL and NZ Post are establishing themselves at Highbrook is seen as a strong vote of confidence in the location.
DHL is already there, and NZ Post will merge its southern and central Auckland mail sorting centres into a single new-technology operation at Highbrook over nine months from July.
Postal services chief Peter Fenton said it was not yet known how many hundreds of its staff would move there, towards what the Highbrook developers predict will be a working population of more than 10,000 within 12 years, but NZ Post would never have considered the location without the motorway interchange.
Manukau City transport manager Chris Freke acknowledged there might be little advantage in joining the motorway from Highbrook during peak-hour congestion, but said the project would prove its worth at all other times by offering a shorter, non-residential route from a key industrial growth area.
Without it, heavy rigs would have resorted increasingly to suburban routes at night and Transit would have had to spent a considerable sum upgrading Otara's motorway interchange at East Tamaki Rd.
"It's a very significant project in terms of promoting economic development within that East Tamaki-Highbrook business area."
