KEY POINTS:
Thousands of holidaymakers this weekend will very probably find themselves stuck in traffic on the series of winding hills of State Highway One north of Auckland.
But, if they raise their eyes from the brake lights in front of them, they may catch a tantalising glimpse of the future - a cutting, a viaduct, a tunnel entrance - away across the hills, in short a by-pass promising deliverance from traffic congestion hell.
The Northern Motorway Extension, parts of which can be seen from SH1 at Hatfields Beach and Waiwera, is the biggest road building project in the country. Due to open late next year, the 7.5km, $360 million toll road and tunnel is designed to solve the notorious congestion problems which bedevil the highway between Orewa and Puhoi.
But, more than that, many people in the north are expecting the extension to be a road to prosperity, boosting development and property prices and bringing Auckland closer for lifestylers and commuters.
The project itself is an engineering marvel. The Herald on Sunday was given a tour of the route, officially known as ALPURT B2, which winds over bush-clad hills and steep gullies.
Environmental concerns held up the project for several years but the diggers from the Northern Gateway Alliance - a partnership between Transit NZ and several construction companies - moved in in December 2004 and around 300 workers have been steadily pushing the route through since then.
The scale of the project is staggering. Whole valleys have been filled and two 380m tunnels have been drilled through Johnstone's Hill north of Waiwera. The deepest cutting in the country - 53m - was blasted and dug through Chin Hill, displacing more than one million cubic metres of rock, most of which has been used as infill.
A lot of effort, some argue, to save an estimated 9-15 minutes journey time on SH1.
But, as holiday drivers know, that is on a good day. The current route traverses three steep and winding sections of hill road, used by large numbers of heavy vehicles. When one of them breaks down or gets stuck - as occurred twice in the past fortnight - queues can extend for several kilometres in both directions.
There has been constant speculation since construction began about the effect of the extension on everything from property prices to the pace of development and population increases.
Rodney District is already the second-fastest growing area in the country. A significant number of people commute to Auckland from towns like Warkworth and Matakana, roughly an hour's drive, and that is expected to rise considerably.
But even in Kaipara District, up to two hours' drive north, people are talking about "when the motorway goes through".
"It should take about 20 minutes off the trip," said Julie Lewis from Sugarbelle's cafe in Maungaturoto. "This place has already opened up quite a lot and it will open up more. People won't be worried about driving to Auckland to work."
One resident said she knew of three people who regularly commuted from Maungaturoto to Penrose.
Real estate agent Jill Morris, from First National Roper & Jones, said the motorway extension regularly cropped up in enquiries from clients looking for property. "People mention it more and more - the influence of the tunnel. It's going to take 20-25 minutes off the trip and people are coming further north to buy their holiday homes.
"A lot of people are coming up here and buying blocks of land, the husbands are leaving mum and the kids here and going back to Auckland to work. There are streams of cars coming back here on Friday nights."
Rodney District Council's manager for environmental policy and planning, Peter Vari, is predicting a trend of "conversions" from holiday homes to permanent residences. "The motorway bringing a higher quality road would mean more people taking advantage of that - they may say, well, now we can drive to Auckland every day.
"People have been talking about it for a good number of years, factoring in better access and prices," said Vari.
Rodney District is undergoing rapid change. The Silverdale North development will see around 2600 homes built by 2015. In Waiwera, resource consent has been granted for a luxury hotel, and a developer is preparing consent applications for 430 units on hills overlooking the village.
But not everyone is so keen on Auckland being brought closer to Rodney. Hans Grueber campaigned unsuccessfully for the mayoralty this month, on a platform opposing the toll road. He described Rodney as "the new El Dorado of New Zealand" but he did not believe the motorway extension would work. "What they are achieving is shifting the gridlock 7km north. People will be sitting there for hours - in the tunnel - and paying $2 for it. They will not like it."
Transit Regional Manager Peter Spies admitted it would take years to solve congestion problems on SH1. The ultimate strategy, over 30-50 years, is a four-lane highway right up to north of Wellsford. But he defended the ALPURT B2 project.
"It provides significant route shortening and safer alignment and far better gradients."
Spies believes the road will be a gateway to a new lifestyle for many people. "I know a number of people starting to move out there and having an apartment in town, with the idea of commuting home on the weekends."
