Ports all around the world have been moved away from their original downtown locations. It frees up the land for better uses, economically and environmentally, and it makes freight and transport far more efficient too. But Auckland can't just move its port to a nearby deserted bay. There are no obvious locations. If there were, it would have been done already.
In 2016 the Port Future Study (PFS) identified 27 potential sites for a new Auckland port, and then readily dismissed all but five of them. The study was commissioned by Auckland Council and focused on the needs of Auckland. It wasn't interested in solutions that moved the port away from Auckland.
That's why Northport, near Whangārei, was ruled out. Not because it wouldn't work, but because this parochial study didn't want to know if it would work.
When Auckland mayor Phil Goff and others say how come the PFS dismissed Northport so easily, but now it's being recommended, that's the answer.
• Premium - Port in a storm: Leaked report says time for action on moving Auckland's port is now
• Premium - Port in a Storm, part 2: Why move the Auckland port?
• Premium - Major study says Ports of Auckland should close, Northport be developed
• Auckland port to pay $24m for Northland stake
The Port of Tauranga was easy to rule out anyway, because its expansion capacity is limited. It can take some of Auckland's freight, but not all of it. In fact, it's expanding now, and the Upper North Island Supply Chain Strategy says that should continue. Tauranga growing to capacity as quickly as possible is an important part of the overall strategy.
The PFS identified three parts of Auckland that seemed best able to have a new port. Two of them focused on the south, recognising that south Auckland is the city's main freight-handling area now and that the "golden triangle" (Auckland-Hamilton-Tauranga) is a growth area with half the country's population.
But the demographic logic is trumped by environmental issues and by straight physics: the alternative sites would be so hard to build on and operate from, it's highly unlikely any of them would work. Some critics have wondered if they were chosen especially to demonstrate the absurdity of moving the port.
Firth of Thames
"Anyone who says it's possible to put a port in the Firth of Thames hasn't done it," says KiwiRail CEO Greg Miller. He's done it – he means, as the former New Zealand head of freight company Toll and a senior executive at Mainfreight, he's tried to stand up a plan to do it.
A port in the Firth of Thames, like the other locations listed here, would be on an artificial island, possibly floating, connected by rail and road on a causeway. It would be somewhere near the head of the Firth.
"First off, it needs reclamation, but using land from where?" says Miller. "Are Tainui-Waikato going to say yes? Next, that water's not deep until Ponui Island (Chambelins, off the southeast corner of Waiheke). It would need a breakwater."
As for the causeway, "it has to carry 1000 tonnes at a time and that means it's enormous, like an underwater pyramid". Then the rail and road would follow new dedicated routes through the Hunua Ranges – much of it tunnelled – to connect in as-yet unspecified ways with the main trunk line and freight terminals at Wiri.
Amazing engineering, but what about the environment? New Zealand is a signatory to the RAMSAR agreement, which protects the nesting grounds of migratory birds. So is China, which is relevant because of every year 5000 godwits and other birds leave their summer homes near Miranda, in the Firth, and fly to China, en route to their breeding grounds in Alaska and Siberia. Miranda is one of the world's great bird sanctuaries and RAMSAR signatories are bound to uphold each other's commitments to look after the birds.
The Firth of Thames is such a complex location, from both engineering and ecological perspectives, Miller says a port would need nine different consents before construction could start.
Shane Jones, Minister of Regional Economic Development is not a supporter: "The notion that the Government is going to pay for a new port in the Firth of Thames, and dig up the Hauraki Gulf, I can assure you that we have no interest in that pipe dream."
Is there a more dangerous piece of sea anywhere in the country than the long beach at Muriwai, wide open to the Tasman Sea? It features the Tasman Surge: a following sea that constantly drags its way down the coast. Ships don't berth with a following sea because that's how they get wrecked.
Perhaps there are engineers who believe it can be done. Doesn't matter, because there aren't any insurance agents who share the dream. Muriwai is a dead location because insurance companies say no.
It's the same for the Manukau. Insurers and the shipping companies all made it very clear, when the PFS proposed Manukau, that they would not support it. The ships won't visit and the insurers won't let them anyway.
Manukau is shallow and would need constant dredging. The Manukau bar, forever shifting, forever uncontrollable, has been a graveyard for ships for as long as they've been visiting. From the available alternatives, Auckland Council's chief economist, David Norman, favours this site.
Greg Miller says it has the same issues with obtaining fill and building a strong enough causeway, and there are ecological challenges there too.
It's almost like the Port Future Study, like Jason and the Argonauts, was steered towards these locations by sirens who knew they would be dashed to pieces on the rocks.