The key to understanding the Government's big new transport spend is Mill Rd. A local road from Manukau to the fast-growing town centres of Papakura and Drury, it will be widened to four lanes and incorporated into the state highway system. Cost: $1.35 billion.
Upgrading Mill Rd is not new. It's always been in the Auckland transport plan, although with a low priority, and it has always been a flagship project for the More Roads Now lobby.
The Government is bringing it forward: design work starts now, construction in 2022 and completion, in stages, is slated for 2025-2028.
But despite what you may hear, this is not a green light for a National Party project. For one thing, there was a $4 billion hole in the last Government's Auckland transport plan, which meant Mill Rd did not have assured funding.
"The big difference today," according to Finance Minister Grant Robertson, "is that these projects are funded. Every dollar required is in the Government accounts today."
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So, it's really happening. But that's not actually the biggest difference. That distinction goes to what's planned for those extra two lanes on Mill Rd.
They will be "managed". It means they might be dedicated to a rapid transit busway. Or they might be dedicated to freight.
NZ Transport Agency chairman Sir Brian Roche said at the programme launch that the purpose is "mode shift", which means persuading those who can that it's better not to drive, but to catch a bus or train or ride a bike. That suggests a busway is more likely.
Robertson said yes, but they might also be a hybrid of both. Roche said NZTA will decide exactly what it means as they go through the detailed planning process.
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The sprawling new town centres of Auckland's south are expected to become home to 120,000 more people over the next three decades, not to mention the enormous commercial and industrial growth also expected. People will live, work and play out there, and they won't all be driving themselves around.
A bigger, better Mill Rd, with dedicated mass transit structured into it, isn't the only news for the south. There will be extra motorway lanes from Papakura to Drury, along with a dedicated cycleway, at a cost of $423 million. This means the three-laning just completed south as far as the Papakura interchange will continue another 6km, to Drury, and cycling south will be a better prospect too.
The rail line will be electrified from Papakura to Pukekohe: a project that's been much desired, much promised on the never-never and now, finally, will happen. Cost: $371 million.
Drury will get two new rail stations, costing $247 million, and a third main line will connect the waterfront port with its inland port at Wiri.
That new line, running parallel to the Southern Line, will allow freight and commuter trains to be separated. The City Rail Link will be able to fulfil its potential by carrying more commuter trains, and the port will be able to use rail instead of trucks to a much larger degree than now.
Mill Rd was a National Party project, to be sure. But not the way it's going to happen now. The road – in all likelihood – will become an invaluable public transport corridor for rapid buses, complementing the growth in rail services. Prime Minister Jacinda Ardern said it's about future proofing, and that's true.
So why isn't that the big headline? Rapid bus network for the booming new town centres of South Auckland?
The same thing will happen with the new roading planned for Tauranga. Why don't they say it there?
The answer is politics. The Government has decided, it seems, that it's too hard just to say they're prioritising a new public transport network. Too many people get too upset because they think it means they will be stuck in traffic forever.
We know from the Northern Busway it's not true: 40 per cent of commuters on the harbour bridge are in a bus, a volume that could never have been accommodated simply with extra lanes for private motor vehicles. We know it from the trains, too: since electrification and improved scheduling, their popularity has also boomed.
Mode shift has already saved Auckland's roads from total gridlock. It's just that it's very hard to explain when a cacophony of voices is saying something different.
So, they now say, they're building roads, and they talk about mode shift and future proofing, and as Ardern said, it's "a leap forward in how we plan and build roads in New Zealand". Roads are for public transport and for cycling, and not just for trucks and private motor vehicles.
But they make sure they keep saying it: they're building roads. Perception (that things will get better with more buses), doesn't lead the way. It follows practice (I caught the bus and it wasn't bad at all). That's the theory.
Green Party co-leader James Shaw was asked at the programme launch if his party would have liked it to be different. Are they swallowing dead rats with those roads?
He said no, there are no dead rats. But he also said if it had been up to them, yes, they'd be spending more on public transport. The message shouldn't be to encourage greater use of private motor vehicles. The Greens have long argued for Auckland light rail, not just an "airport line" but a whole network.
However, Shaw added, $1.1 billion more is to be spent on railways, bringing the total Government commitment up to $4 billion. "It's a significant programme of multi-mode shift."
The Deputy Prime Minister, Winston Peters, agreed with that. He pointed out, rightly, that most other countries are reviving their rail networks, especially for freight, "but until recently we've been going in the other direction".
He also enjoyed saying that New Zealand has suffered under "a malignant, derelict, brainless policy of running rail down to sabotage a key strategic asset in this country." It's election year, after all.
And what will happen about light rail? It wasn't in the new plan, but possibly it will turn up in the $4 billion of new spending the Government has still to announce. Transport Minister Phil Twyford said a decision on rapid transit to the city's northwest would be announced "soon". The city-to-Mangere light rail options will go before Cabinet in March.
Will the Government go into the election with a clear plan to progress light rail in Auckland? The Prime Minister said, "That is our intention."