Discussion of another harbour crossing has been in the news a lot recently as a result of Mayor Wayne Brown pushing for a bridge from Point Chev to Birkenhead. While I believe his proposal is bad, at least some of his reasoning behind his push for a bridge is correct. As reported by Stuff:
However, the Mayor wants to scrap that idea too, believing the tunnel will never happen and is proposing a bridge from Meola Reef to Kauri Point, which he believes would eventually pay for itself.
“It starts with the fact that the tunnel is a bad idea,” Brown said.
“We’ve got experience with tunnels in Auckland with the CRL (City Rail Link), they always cost twice as much as they say they’re going to cost. And they said that one was going to be $17 billion which means $34 billion which is the entire budget for transport in New Zealand for 10 years.
“It goes from a traffic jam on this side to the same traffic jam on the other side. So it doesn’t solve any problem, because the bridge isn’t congested at all.”
The proposed tunnel would go from Northcote on the Shore and link up with the motorway system in central Auckland and the Mayor doesn’t believe this would alleviate traffic woes.
“Having a tunnel doesn’t help that at all. And so I’m looking at what is wrong with what the offer is, then is there an alternative?” he said.
…..
“It goes 80% across the Harbour, the reef at low tide, and you can either put a causeway or even a whole series of low bridges,” he said.
“No boats go underneath that, because they’d go aground. And then you have a short bridge to the other side that’s way cheaper.”
Here we go again…
The current proposal reminds me of an image from one of the older motorway plans, which was brought up again by a former ACT candidate in 2018. In other words, this is not the first time people have looked at the map and been tempted to draw this particular line, regardless of the actual terrain.
The recurring flaw in this idea
The key problem with this proposal is highlighted (in the aforementioned Stuff article) by Councilor Richard Hills: what happens where the bridge lands.
“The main issue is there’s nowhere for the road (either side of a bridge) to go. It has to join up to somewhere.
“If you did have a bridge that managed to get up that gradient above Kauri Point through all those beautiful nature reserves, then it would go into very small local roads.
“I’m not sure where you would put the motorways or the connections into that, so you’ve got small communities there.
“It’s not so much the structure itself, which I’m sure would have many issues with consenting, but where do all the vehicles go once you cross from essentially the zoo, into Beach Haven and Chatswood?
“Although it’s a good idea to look at other options, I think that one would be fairly impossible.”
The issue of connections also applies on the southern side: do we build a motorway through the zoo or hundreds of houses, or do we need to build a series of tunnels, the exact thing the mayor is trying to avoid? The Mayor claims this isn’t an issue:
“When they built the bridge (to North Shore) there wasn’t a motorway anywhere. The motorway comes as things develop.
“In the fullness of time, motorways might upgrade. But the idea that you have to do the motorway straight away doesn’t reflect what’s happened.
That sounds an awful lot like building a bridge for the sake of building a bridge, rather than starting with the strategic question of what problem you’re trying to solve.
There are plenty of other issues with the Mayor’s version, starting with the fact it doesn’t do much for public transport or for active modes. Frankly, when pretty much every other water-crossing in the city has been improved in recent years for active and public transport (think: the SH16 causeway, the new Panmure Bridge, walking and biking access alongside Pahurehure inlet, and more), it’s wild to be suggesting a new Waitematā crossing that doesn’t foreground those missing modes.
I’m also not sure just how viable Meola Reef is either. I recall reading many years ago about some earlier studies suggesting that while volcanic lava flow that formed the reef is hard, that it’s sitting on softer sedimentary rock, meaning that it is not strong enough to support a bridge or motorway. If I’m recalling that correctly – and let us know in the comments if you have the details to hand – it makes the Mayor’s proposal even less feasible.
What the Mayor gets right
The Mayor is right, though, about not building tunnels. The current plans as held by NZTA Waka Kotahi are hideously expensive, and previous analysis has shown that they will only serve to make congestion worse as well as undermine many of the goals to make the city centre more successful and people-friendly.
Moreover, not only would the proposed tunnels be hideously expensive to build, they’d also cost a lot more to operate. The opening of the Waterview tunnels brought with it tens of millions in annual operations and maintenance costs alone, increasing the cost of running the entire Auckland State Highway network by almost 30 per cent. Much longer tunnels under the harbour will cost a lot more than that, adding a huge amount to the ongoing opex of keeping the network running.
And finally, an under-talked about impact of the tunnel proposal is the disruption that building it would cause.
Here is a design from the 2010 proposal. While there’s bound to have been changes since, much of the plan is likely still similar. As you can see, it involves building a series of cut-and-cover tunnels and trenches throughout the western city centre. Picture a decent chunk of Victoria Park needing to be turned into a staging yard, much like you see around Maungawhau for the City Rail Link today.
So what’s the answer?
To me there are two key questions that need to be answered.
- What form (and location) would a new crossing look like
- When is it needed.
Form
We agree with the mayor that a bridge is vastly preferable to a tunnel. Bridges are faster and cheaper to build, easier to maintain, and safer. And travellers – especially those using public transport, and walking, biking or jogging – haved a chance to enjoy the view. A bonus: the view goes the other way, too, as a well-designed bridge can enhance a city’s skyline and become a feature in itself.
The next question is, what and who are we building the bridge for? The good news is, NZTA has already done their homework on this. A 2018 study confirmed that even the introduction of a small cost to cross the harbour from a road-pricing scheme would effectively remove the justification for any new road crossing. So, it’s timely and fortunate that this government has clearly said they plan to introduce road pricing. Moreover, that study and another one in 2020 showed that the best option was to build the missing modes first – public transport and active modes.
Portland’s Tilikum Crossing is an example we’ve highlighted before, of a bridge built to provide the missing modes of public transport and walking and biking. It’s also really nice to look at, and an interesting, attractive and accessible feature of the city for locals and visitors alike.
This option is something we’ve highlighted numerous times before. It’s extremely frustrating that in 2021 – when the previous government was looking at a ~$700 million pedestrian-bridge for people walking and cycling – Waka Kotahi said it would only cost around an additional $1 billion to have included public transport in the design. At the time they didn’t recommend that particular option, because they claim they were only asked for an active mode bridge. I suspect there was also an element of not wanting to propose something that would solve the problem but that would hinder them from building more road lanes.
There is, however, potentially a case for some additional road capacity.
This data comes from Waka Kotahi, and shows the average weekday traffic volumes across the bridge by direction. As you’d expect, there is more traffic travelling to the city in the morning, and more travelling away from the city in the evening.
However, in practice the configuration of the bridge is also changed so the peak direction gets five lanes while the counter-peak direction has just three. This results in the counter-peak direction moving more vehicles ‘per-lane’ – or to put it another way, perhaps counter-intuitively the counter-peak direction is busier than the peak direction. Potentially including a couple more road lanes in a new crossing, so both directions always have the same number of lanes available, thus removing the need for the barrier machine, is something that might make some sense.
For those worried about the lifespan of the clip-ons, a new bridge that adds the missing modes plus those lanes mentioned above, in combination with road-pricing, could be enough to reduce demand on the existing bridge by enough that it would allow you to remove the clip-ons and replace them with new ones. And all of that is still going to be way cheaper than just a pair of road tunnels.
Timing
If a new road crossing was to be built, the key question of when it is needed is perhaps even harder to answer.
Traffic grew fairly consistently over the Harbour Bridge from its opening in 1959 all the way through to 2006. However, since then, things have been less predictable. When the busway opened, it became a massive instant success – meaning at peak times, 30-40% of all people crossing the bridge are doing so on a bus. The Global Financial Crisis also likely had an impact, but traffic continued to rise before plateauing at around 171,000 per day before COVID struck. After which, all bets are off: even this year so far, figures are hovering at less than 160,000 per day.
It’s also interesting to compare the actual traffic volumes to what was predicted in the 2010 business case, which had assumed growth would continue and that a new crossing would be needed in just a few years:
One of the things driving the change in trends at the moment has been the rise of working from home, with noticeable drops in volumes on Mondays through to Thursdays.
This does highlight that predicting when we’ll need something is incredibly hard, as there are many unexpected or unpredictable developments that can have significant impacts on the future demand.
So to that end, we should focus our immediate attention and resources on the things we already know we need, and which are demonstrably needed right now – the missing modes – and then see if we still need something else.
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Just crossed the bridge this morning, on a bus at ‘peak’ time (8am), crusied across at 80kmh all the way. I still don’t know what problem we are trying to fix and Wayne Brown, Labour or this Coalition haven’t been able to explain it.
Congestion? The bridge isn’t congested
Resiliancy? I imagine the availablity of the bridge is at about 99.99%. There is also another crossing on Upper Harbour
Public Transport? It’s been clear the tunnels would be for cars first pushing PT over the harbour into the late 2030’s
Once again, 6 years of wasted Labour Government, could have had Light Rail as our mode of choice and instead of a ridiculous bike bridge just spent a couple of billion more and done a PT and Active Mode bridge.
Reality is, nothing has been built and lots of things proposed because its simply not needed and all political parties know it. It makes you look like your are serious about infrastrcuture by proposing things you’re never going to be around to deliver.
Ask any driver trying to get across the bridge and they will tell you the same thing, queues to get onto the motorway. Continual Buslanes everywhere we can roll them out would be a game changer and at little cost.
I cross the bridge on the NX1 before 7am, never a problem. The southbound busway joins general traffic after all the other merges, so the traffic is generally flowing well.
Coming home is a different story. The buses get stuck in general traffic, however the cause of that traffic jam isn’t the bridge – it’s the motorway further north.
What’s needed is a dedicated bus lane from Fanshawe northbound over the bridge to join up with the existing bus shoulder lane.
Yeah it’s ridiculous. A busway/bus lane is needed right through the CBD – Customs, Fanshawe – proper bus priority, etc – stop cars turning out of car parks like at Bradnor lane holding up full buses. That BP on Fanshawe should be closed. Not to mention the idiotic planning with cars always turning in front of buses to turn left at Victoria park – the same idiotic planning happens in the morning by the Fonterra building – single cars holding up multiple full double decker buses. Ban the left turns.
It can take 15 mins just to get to the on ramp – and then deal with Curran st, etc.
The Auckland Harbour Bridge Authority commissioned a report by the original bridge designers Freeman Fox into a potential crossing via Meola Reef. Their report in August 1974 included borehole data from Tonkin and Taylor confirming that the hard basalt of the reef was sitting on soft sediments so their proposed structure would require deep piles anchored into the bedrock beneath – although it reckoned that the reef would provide some lateral support to improve earthquake performance. The critical thing is that a whole new motorway route would be required, partly through Point Chevalier but mainly via Birkenhead and Glenfield.
The Mayor offered a proposal and said there maybe other better options. The Herald published a proposal a few days later showing a bridge 500m west of the existing. It needs more thinking.
SH18 causeway across the mudflats has arguably worse ground conditions than the reef. If a 43m clearance bridge is built over the channel, it’ll already be half way up the hill at landfall. It’d be similar to the upper harbour bridge. If it was just a lane each way like the original Upper harbour bridge it could connect Motions Rd to Onetaunga Rd.
I want to see the introduction of travel demand management first thou, which should defer any need for another bridge for a long time
I like the last graph title being its legend – nice.
Exactly. When traffic counts over the bridge have barely changed in twenty years, just what problem are we trying to solve? If hard-headed business analysis was applied to the “problem” you would conclude that if investment in growth was to occur, it would be worth putting it into an option which has experienced significant growth over the last twenty years – public transport. And if road pricing (didn’t we use to call that “tolling”?) was imposed – which the present government and the mayor seem to favour – then the “problem” might go away of its own accord.
Surely this option would appeal to a government which is ideologically driven by “value for money” and opposing “white elephant” infrastructure projects?
But it seems that they are more driven by inconsistency and hypocrisy than by any loftier principles. I just hope that they are as good on the delivery front as Labour was and that we don’t end up with something we don’t need and which will make our city even more congested.
If hard-headed business analysis was applied to the “problem”, other parts of the region like the South might be higher investment priorities than a *third* way to get to the North.
Like a Southwest RT line perhaps? Ooops! That might end up looking like something Labour proposed!
The government, and many of it’s MPs are acutely aware of their sponsors, donations and therefore their interests.
Interests very much aligned with enlarging motoried road transport facilitation, and excluding any mode shifting initiatives.
Politics, posing as economics, once again and stuff the environment.
Yep, just now according to RNZ they want to increase the number of public servants commuting to the office to…. wait for it… increase parking revenue.
It is just sad.
We are still intent on building the wrong thing first.
We are counting car movements, as a proxy for people movements.
Providing a spacially more efficient way of moving a significant proportion of the people. and the cost savings in construction, operation, and ancillary provision such as journey end car parking will be immense.
Tunnelled, (or bridged) light rail under the harbour and a mix of on and off road, surface, tunnelled, and perhaps elevated at each end has the potential to add considerable extra people carrying capacity across the harbour choke point at much lower costs then expanding road capacity wherever it is located.
We just need to look at Sydney for inspiration and it’s newly opened under harbour Metro lines.
Electrified twin light rail tunnels are a modest 6.2 m diameter and have much reduced ventilation and fire suppression requirements over the comparitive twin 14m diameter Waterview tunnels. So less then 20% of the excavated volume.
But arguably have more people moving capacity.
You’re probably right, but car-heads will need to be thrown a bone in order to get a bridge crossing over the line.
To be honest I don’t see another crossing ever happening, unless they are realistic.
The meola reef idea seems like a great transit crossing idea at first but like the road crossing it seems to create more problems than it solves.
Yes it would be nice to see proper transit serving western North shore, I can imagine Birkenhead and Glenfield becoming a bit like north Sydney and crows nest with more apartments and commercial space.
But on the southern side of the harbour there already is more planned transit to the west like the north west bus line, this will make it very difficult to to build a connection between point Chevalier and the city, this will create a situation where all transit enters the city from one direction, so many expensive city loop systems will need to be built.
I personally think a lower bridge should be built slightly east or slightly west and the sugar factory and navy will need to use barges to move freight upper harbour. The new bridge could still have some car lanes on it, so the clip-on lanes could be removed.
In reality this will never happen, not in the next 30 to 50 years anyway, so most of us will be lucky to see it completed in our lifetime.
I think a small bridge linking Beach Haven with the Upper Harbour Highway could be of value.
All the current traffic and PT from Glenfield south heading east before joining the gridlock leading up to the bridge could instead go west to UHH and then onto the NW Motorway. Buses would get access to the NW Busway and the cyclists to NW cycleway. Could be buses to the western line as well.
Has anybody seen any data on what changes to the ferry service have meant for bridge traffic? I can still remember when the Birkenhead ferry service would whisk many hundreds across the harbour in peak hours. I’ve recently used it a few times and the numbers are a fraction of what they were.