Last week we moved a step closer to finally gaining walking and cycling access over the harbour bridge with the councils transport committee giving it’s support to the Skypath proposal. There are still a number of official hurdles to jump through before there is any talk of actually building it, but no good project gets the go ahead that easily. As sure as night follows day, there are always bound to be a number of NIMBYs that have something to complain about. Some NIMBYs are just so opposed to any change that I am surprised they manage to change their underwear every day without getting into an argument with themselves. Sure enough the NIMBYs have started to raise their heads on this project.
In this story yesterday groups on both sides of the bridge have piped up.
Tony Skelton of the St Mary’s Bay Association spoke to the committee about concerns around the proposed entry and exits and questioned proposed patronage and profit numbers.
”Without those numbers then how on earth can you consider this?” he asked.
The project is being privately funded and the numbers have been independently checked by Ernst & Young. So what business is it of a local residents association to oppose the project? Clearly the members of the association do not see the value in the project, likely because they personally don’t intend on using it so believe it will be underutilised.
That contrasts quite highly with the stance of the well known NIMBY group – the Northcote Residents Association. This group has a history of NIMBYism having stopped the initial proposal to have a busway station that serves their area. The arguments these people come up with can really be quite comical. In this case:
Northcote Residents Association chairwoman Carol Brown said SkyPath users driving to the bridge will clog up residential streets. She said it should be connected to the Shoal Bay pathway.
Right … So it will be so successful that people will drive from all over the North Shore, park in their streets, then get out their bikes and ride to town? Give me a break. Everyone I talk to from the Shore tells me that the problem is never the bridge itself, but actually getting close to it. By the time you get close to Northcote point in your car, you might as well carry on all the way to town. The majority of cyclists that will use the bridge will get there by … cycling. If local parking does become a problem then perhaps they could get Auckland Transport to implement a special parking zone, like they are currently trialling across the water in St Marys Bay. These people can really be frustrating at times.
On the subject of NIMBYs, it seems the Milford ones have won in their battle to stop intensification around the shopping mall.
Allowing people to walk or cycle across the harbour bridge is an aspiration that has been a long time coming. When the harbour bridge was originally proposed it included walkways, like Sydney’s harbour bridge, but the government of the time was concerned about ballooning costs and in the end all we ended up with was a four lane traffic bridge. Then when the clip-ons were added in the late 1960s we ended up with an eight lane harbour bridge but once again no ability to walk or cycle across the Waitemata Harbour.
While in recent times there have been concerted efforts to push for a walk/cycle connection across the harbour, I must say that most of the time I thought it was more aspirational than having a real chance. Particularly as NZTA continue to have a measly budget for walking and cycling projects in Auckland. However, a report to Wednesday’s Transport Committee meeting suggests that there’s actually a feasible and viable plan for making this project become a reality – a plan which doesn’t have to cost ratepayers and taxpayers a single cent: it only requires a commitment in terms of taking on revenue risk liability.
The report begins by outlining updates to the project since it was last brought to the Committee’s attention – back in August 2011. The updates are:
- The AHB Pathway Trust (the Trust) has developed a lighter structure by using aluminium in the central span;
- Auckland Transport (AT) has undertaken a review of the SkyPath’s business case and referred it back to the Council to consider funding sources;
- A range of capital costs for the project has been identified between $28 and $41 million.
- There is still uncertainty about the capital costs, however for the purpose of the financial analysis in this report a cost of $31 million has been assumed (as outlined in paragraph k) in Attachment A);
- Update of information in the Trust’s business case and public private partnership (PPP) proposal;
- Comparison of the SkyPath to the rest of the transport and cycling and walking programme;
- Quantification of the Council’s contribution to the SkyPath; and
- Initial identification of project risks (outlined below in paragraph 20).
Oh, and the Trust also created a pretty cool image of what the Skypath could look like at Christmas time:As I understand it, the proposal for constructing the project is through a PPP between the public agencies involved (Auckland Council, Auckland Transport & NZTA) and what’s referred to as the “PIP Fund” – a private company willing to take on the 25% highest level of revenue risk and to fund the project up front. Payments for crossing the bridge – in the form of a HOP Card or cash – would raise the revenue required to cover capital repayments for the project and operating costs.
Here’s the proposed toll levels:While the report goes to painful lengths to note that this is just the beginning of the process for making the project a reality – in terms of getting official Council support and for Council to take on the revenue risk of the project (not to mention the possible long term requirement for maintaining the structure) – this is a really exciting step forward. And while the PPP structure isn’t perfect (why should we pay a toll to walk across the bridge when we don’t have to pay one to drive across it) I think it’s highly likely in the future that things will change and perhaps NZTA will realise it’s a transport agency rather than just a roading agency – and they’ll take on ownership and responsibility for the structure.
Plus the case for the project is pretty compelling – particularly if all logic and sense tells us that an Additional Waitemata Harbour Crossing (in motorway form at least) should be a lot more than 20 years away. In a nutshell, the report makes a really good argument for the suggested approach:I sincerely hope that at Wednesday’s meeting the Transport Committee at least gives this approach a go. I think that not only would the pathway be a great transport connection and tourist attraction – but I also can think of it as an incredibly fun thing to wander across on a sunny summer’s day.
Here is a Cycling Auckland’s call for support for the project [thanks Max]:
Over the last few months we have done quite a number of posts looking at the issues of a potential new harbour crossing and I think that it may have started to frustrate some from the North Shore. particularly councillor George Wood. He has became much more vocal on the issue though social media and calling for the bridge to be built as soon as possible. Well it seems that it has attracted the attention of the Herald who ran a piece today about it that has provided some useful information about the need for the project. I did have a little laugh right at the start as one of the things I had questioned earlier in the year was if there would be any North Shore politicians who would actually stand on a platform of not building another road crossing
North Shore leaders will this year ramp up calls for a new Waitemata Harbour traffic crossing, even though the Transport Agency does not believe one will be needed before 2030.
Although the agency expects to update an application to protect a preferred route for tunnels under the harbour towards the end of the year, Auckland Council member and former North Shore mayor George Wood fears complacency setting in.
He says community groups such as the Northcote Residents Association want to be involved in planning for a new crossing but are being kept in the dark about a proposal which follows at least six studies since 1986 and doubt about the longevity of the existing harbour bridge.
Arguing for the bridge on the grounds that it is old and could fall apart seems to have been a mainstay argument for those that want a new road crossing and helpfully the NZTA have addressed this.
Having recently spent $86 million strengthening the bridge’s two clip-on structures, the agency is focused mainly on its ability to cope with increasing freight loads.
Mr Town said that with careful management, there was no reason why the 54-year-old bridge could not last for another 100 years. But he said the “critical path” for bridge loads was heavy vehicles travelling on the northbound clip-on lanes, for which forecasts indicated a new crossing would be needed by 2030.
Even so, the agency did not want to build the new crossing too early, for cost reasons.
“It’s expensive, so getting the timing right is the thing,” he said.
The agency in early 2011 estimated the cost of a pair of road tunnels at $5.3 billion compared with $3.9 billion for a new bridge, and the Auckland Plan cites a figure of $5.8 billion to include future provision for trains.
Mr Town acknowledged that technological advances were likely to reduce tunnelling costs, while those for a new bridge were unlikely to fall markedly.
But he said “one of the big unknowns” was what the completion in 2017 of the western ring route with its connection to the Upper Harbour Bridge at Greenhithe would do for heavy traffic movements.
“It will provide a genuine heavy traffic option – between 2017 and 2021 we will be looking really closely at travel patterns.”
So the bridge is obviously fairly structurally sound and the issue then becomes a question of when the clip-ons need replacing. The NZTA seems to admit that it will depend a lot on what happens after the completion of the Western Ring Route. You may also recall that we found that the traffic predictions that had been used in the previous business case used incorrect data so it is quite possible that combined with the WRR this could see the need for replacing the bridge pushed out a lot longer than 2030.
Traffic volumes predicted in the AWHC business case vs actual
The other major issue with a new crossing would be the impact on the city centre. The current thinking is for the new crossing to link directly into the existing motorway system and to turn the harbour bridge into a kind of big off ramp. By taking the through traffic off the bridge, it would leave a hell of a lot of unused capacity on there which would have the effect of making it easier to drive to the city. That would severely impact not only the performance of the Northern busway but would see potentially thousands more cars per hour dumped into the city centre when all of the councils plans are focused on trying to reduce vehicle numbers that area.
So far everything seems to point to the conclusion that we are both unlikely to need the crossing for at least a few decades and that even then we might not want it due to the impact it would have on the rest of the city. That kind of brings me back to my question from earlier in the year and wonder when will we get a politician who is brave will actually stand up and say this to the residents of the North Shore?
I think the other thing worth pointing out from this article is it confirms that the NZTA are now looking at a combined road and rail tunnel like has been done in some places overseas. In this situation the tunnel diameter is big enough that a train line can be run below the road deck as shown below. If we must have a new road crossing then it does make sense to do it this way and it is interesting to see the NZTA say that the tunnelling costs are likely to reduce as the technology improves. My preference at this stage however would be for a dedicated and much cheaper rail tunnel first and to only build the road crossing if it is still needed after that (the business case costed a rail tunnel at $1.6b vs $5.3b for a road tunnel).
In the fallout from the release of the City Centre Future Access Study last Thursday and the government’s rather bizarre response to it, for some reason there seems to have been renewed discussion about the Additional Waitemata Harbour Crossing (AWHC) project. It’s a bit odd to think that if Central Government has concerns about contributing to a $2.4 billion project they’d end up looking more kindly on a $5 billion project instead, but I guess as it’s a road rather than a railway line you really never know.
We’ve discussed the AWHC project on this blog many times before, most particularly recently pointing out some incredibly dodgy traffic statistics used by NZTA to help justify the project. In this post I’m not really going to focus on the cost of the project, or the heroic traffic growth assumptions or even why a rail crossing is a much more sensible option. What I’m going to simply look at is the likely traffic effects of the additional crossing – where it does and does not add capacity to the system and what the impacts of that are likely to be. There’s a wealth of information on the project website, which I will draw on to inform this. For a start, let’s just get a rough idea about what the AWHC project is – something that’s reasonably well illustrated in the diagram below:It’s a little complicated with all the different colours, but let’s just think about what happens for southbound traffic:
- Traffic heading to Shelly Beach Road, Fanshawe Street and Cook Street uses the existing Harbour Bridge
- Traffic heading to SH16 west and SH16 port exits uses the new tunnel
- Traffic continuing south on SH1 uses the new tunnel
The same is obviously also true in reverse. Oh an by the way I wouldn’t get too excited about the rail tunnel shown above – the fact that a shuttle line from Gaunt Street to Akoranga is shown, with no connections to the existing or proposed rail network at the city end, just illustrates that it’s only in there as a token gesture.
At the moment in the morning peak there are five lanes southbound coming over the harbour bridge. The Shelly Beach Road offramp peels off but the five lanes remain through St Mary’s Bay. Then one lane drops off at Fanshawe Street and four lanes continue southbound over the Victoria Park viaduct: two of those feeding into Cook Street and the SH16 exits and the other two linking with the Southern Motorway for trips heading further south. Ignoring the city exits (Shelly Beach, Fanshawe and Cook Street) for a minute, it’s clear that there are four lanes that link the Harbour Bridge through to SH16 (for east and west travel) and SH1 for travel further south. Here’s a diagram showing the future layout of the motorway network with the AWHC built:
It’s a bit confusing at first, but once you ignore the local roads it starts to make a little more sense. We can see that southbound in the morning peak there would be three lanes in the new tunnel and four lanes (one of which is a bus lane by the look of it) coming over the harbour bridge. The new tunnel effectively removes ‘through traffic’ from the Harbour Bridge, but doesn’t actually add any capacity over what already exists for that through traffic.
- There’s still only two lanes which continue right through for southbound traffic.
- There are only three lanes (compared to the current four) for traffic heading to either SH1 southbound or the SH16 exits.
What the new road does do, of course, is free up huge amounts of new roadspace for vehicles travelling from the North Shore to the CBD. There are now four southbound lanes over the harbour bridge worth of capacity – all of which can only link to Shelly Beach Road, Fanshawe Street or Cook Street. That’s potentially an absolute flood of additional vehicles that could be funneled into central Auckland because they no longer need to ‘compete’ with the through traffic for roadspace over the Harbour Bridge.
This impact is well documented in the project’s Local Roads report:
The main challenge for this assessment relates to the provision of additional capacity across the harbour and the potential flow on effects this may have on the local road network around central Auckland and feeder roads on the North Shore, particularly in the weekday morning peak. In particular it is noted that the new harbour crossing will allow more traffic to enter the CBD. This conflicts with various CBD strategies that encourage the provision of public transport for trips to/from the CBD and not to provide additional capacity for cars.
It fundamentally conflicts with the concept of a liveable city centre.
It is anticipated that space on the existing Harbour Bridge will be allocated to public transport, walking and cycling, if an Additional Waitemata Harbour Crossing is provided. The precise lane configuration on the existing Harbour Bridge will only be determined over time and this will significantly affect the predicted traffic effects of the additional crossing. The scenario agreed for this study (for both bridge and tunnel options) includes the following lane allocation on the existing bridge:
- One lane for walking and cycling;
- A bus lane in each direction, but with general traffic heading to the Shelly Beach off ramp sharing the southbound bus lane; and
- Five general traffic lanes in total, assumed to operate with three southbound and two northbound lanes in the weekday morning peak, with the reverse in the evening peak.
This scenario would provide three southbound lanes for general in the weekday morning peak plus additional capacity, equivalent to around half a lane, for general traffic heading to the Shelly Beach off ramp. This scenario also provides the opportunity for a significant increase in the rate of flow from Esmonde Road (and Akoranga Drive) onto the Northern Motorway, thereby increasing the rate of flow able to cross the Harbour and reaching the Auckland CBD.
It’s hard to know whether to laugh or cry about the fact that even after spending $5 billion NZTA still can’t bring itself to providing a proper dedicated southbound bus lane. The important thing to note from the above paragraphs though is at the very end: the real impact of the project is a massive increase in flows from the North Shore into the CBD. As no additional capacity is provided south of the CBD the are few gains there aside from being able to hit the gridlock through spaghetti junction a bit quicker because vehicles travelling through the tunnel no longer need to compete for roadspace with those heading for the CBD.
It seems as though the report writers began to realise this fundamental flaw with the project and therefore ended up recommending retaining some measures to limit the flow of vehicles onto the motorway from the North Shore:
A range of options could be used to limit the rate of flow able to cross the Harbour, including changes in the lane allocation. However, for the purposes of this assessment it has been agreed that the effects of the additional crossing will be assumed to be restricted by some means and that this should be reflected by modelling ramp signals on the important Esmonde Road southbound on ramp. Capacity constraints are already predicted to exist on the approaches to or on the other on ramps during the morning peak, and providing ramp signals at Esmonde Road will therefore further constrain the rate of flow able to pass across the harbour and into the Auckland CBD.
So we’ll spend $5 billion on adding a huge amount of capacity across the Waitemata Harbour but we’ll still need to use things like ramp signals to limit the flow of vehicles onto the motorway – doesn’t that kind of defeat the purpose of the whole project?
The impact of the project on some city streets is pretty massive in terms of additional vehicles – especially Fanshawe Street and Cook Street (Curran Street and Shelly Beach Road, two residential streets, get slammed as well):To cut what is becoming a pretty long story short, it really does seem as though the AWHC project involves spending $5 billion to make it easier to drive your car into the city centre – something we actually don’t want you to do. In other words, it is building the most expensive transport project ever to create more congested inner city streets and a less liveable city centre. It’s a huge amount of money on something that will make Auckland a far far worse city.
For that reason, it is quite simply the stupidest transport project ever.
I found myself in an interesting discussion on Twitter yesterday about the Northern Busway and whether a North Shore railway line is likely to be necessary at some point in the future or not. This is a fairly common debate, but one that’s often a bit ill-informed by the assumptions that people make. Things like:
- Rail to the North Shore is really expensive. Well yes it is, but not nearly as expensive as building a $5 billion road tunnel.
- The North Shore already has a busway, why does it need a railway line? And here’s where things get interesting – read on!
While the North Shore certainly does have a busway – a very successful one at that – we must remember that the busway proper is only between Constellation and Akoranga Stations in both directions, then between Akoranga Station and the Onewa Road interchange in the southbound direction. In some other places there are bus shoulder lanes, but that’s it. When you actually start to map out how much of the Northern Express route (the core route along the busway) is busway (blue) bus lane or shoulder lane (green) and mixed traffic (red) the result is actually somewhat surprising:Breaking down the distances, you can see that northbound passengers in particular get a pretty raw deal:Total it all up and you actually find that only 41% of the Northern Express’s route is actually along the busway proper. A full 40% of the route is without any form of bus priority measures at all – including half of the route for northbound buses. Most worryingly the places with some of the patchiest bus priority measures, like the Harbour Bridge, St Mary’s Bay for northbound traffic and around the Britomart departure points are the very places where bus volumes are the highest and the competition for road space is most intense, with buses sadly losing out. For example, the fact that NZTA didn’t bother to put a northbound bus lane through St Mary’s Bay when widening that motorway speaks absolute volumes of the disdain that organisation has for public transport.
The point of all these calculations isn’t to criticise the Northern Busway, but actually to point out that a railway line south of Akoranga – like the rail line shown below - wouldn’t actually duplicate much of the busway at all: just the southbound section between Akoranga and Onewa which would be very handy for minimising the length of a cross-harbour tunnel:Furthermore, this is pretty much exactly the same section which NZTA’s Additional Waitemata Harbour Crossing Project adds capacity to – at a cost of at least $5 billion (a rough estimate based on past analysis suggests that a Takapuna to Aotea rail link should be able to be built for under $2.5 billion). After all, the only thing AWHC does is shift ‘through-traffic’ off the harbour bridge into a new tunnel and then turn the harbour bridge into giant on and off ramps feeding a heap of cars into downtown that we don’t actually want. For $5 billion!
Clearly in the meanwhile there are things we can do to improve the busway and increase the measly 41% total. An extension northwards from Constellation to Albany is a no-brainer. Improved priority measures in the inner city is another clear requirement, plus we need to do something about getting a bus lane northbound through St Mary’s Bay. But for goodness sake, before we go and spend $5 billion on a road tunnel that’ll do nothing but feed cars into downtown, can we consider a much cheaper and much more effective alternative?
Following on from my post this morning around the Harbour bridge, I was pointed to this article from the US on trends on the amount of vehicle miles travelled each year. The post starts as
It’s now common knowledge that annual changes in the volume of driving no longer follow the old patterns.
For 60 years, the amount of vehicle miles traveled (VMT) rose steadily. Predicting more driving miles next year was like predicting that the sun would rise or that computer chips would be faster. The only direction seemed to be up.
Then, after 2004, per-capita VMT fell 6 percent, which has led to a decline in total VMT since 2007.
The most recent data are from July, traditionally America’s biggest month for driving. In July 2012, Americans clocked over 258 billion miles behind the wheel, a billion fewer miles than the previous July despite a slightly stronger economy and cheaper gasoline. In fact, you’d need to go back to 2002 to find a July when Americans drove fewer miles than July 2012.
Has America’s long increase in driving turned a corner or just taken a prolonged pause? The answer matters a lot.
They have then gone further and done some modelling of what the graph might look like based on a couple of scenarios:
But what surprised my was just how similar the graph on the numbers is to what we see with the harbour bridge so I decided to do some similar modelling. I looked at the average year on year percentage increase for four different time periods and modelled them out to 2027, 15 years from now.
- From when we can first get data for the Harbour bridge in 1975 through to when the volumes peaked in 2006
- From when we can first get data for the Harbour bridge in 1975 through to 2012
- The last decade from 2002 to 2012
- Since traffic peaked in 2006 through to 2012
Doing so gave a spooky familiar graph even though they are looking at miles travelled while we are looking at vehicles per day over the bridge. Here is what our result looks like:
As I said they are remarkably similar and just like the post we have to ask ourselves, are we really going to see a return to the old days? Sure there will probably be a bit of a pick up in the future if the economy improves but it seems hard to imagine it will be anything like what we have seen. Especially because the drop off in vehicle numbers preceded the global financial crisis, as it has done all over the developed world and because we know that on this particular route that thousands of people have chosen to use the Northern Busway once that opened. And are likely to continue to as improvements continue in Auckland’s transit systems.
The author of the US post comes to the same conclusion:
It won’t be surprising if an upturn in the economy leads to some increase in driving, especially if gas prices don’t also surge. But it’s harder to imagine that we will switch back to the sizeable increases in VMT that took place almost every year for six decades after World War II. Even if driving continues to increase at the rate of population, this would be a long-term slowdown that should correspond to major changes in transportation policy.
With the important observation that:
While we can’t yet see “the new normal,” it’s a good bet that it won’t be the same as the old normal.
Do we really want to be making $5 billion bets based on this uncertainty? Or should we pay more attention to this seven year old change, as it may well be generational, as the article urges:
Congress needs to stop trying to build out our grandparents’ transportation system.
Well certainly not unless they can guarantee the petrol prices our grandparents paid too.
Here at the Auckland Transport Blog we have finally found a road project that seems more unwarranted than either Puhoi-to-Wellsford or Transmission Gully. This is a road project that costs more than both of those two premature white elephants combined. Yes, we’re talking about the “Additional Waitemata Harbour Crossing Project“.
We often hear how important and urgent it is for Auckland to get another crossing over the Waitemata. This message is usually swaddled in one or more of the following soothing spoken reasons:
- Congestion is bad, i.e. your valuable blogging time is being wasted.
- The clip-ons are going to fall off, i.e. you better learn to swim.
- It’s always been in the plans, i.e. you can’t stop it now.
Let’s consider each of these arguments in turn and see whether they hold much sway.
First, the sweet smell of congestion – that addictive road building tonic that both demonstrates the folly of designing cities around private vehicles, while simultaneously providing the justification for continued investment in private vehicles. This is the same circular logic that entrapped the entire city of Los Angeles for decades, and which still seems to prevail within the MoT and NZTA. The thing with congestion is that you can never beat it by building more roads – investing in the latter usually simply enables congestion to grow back, it’s like NZTA want to spray water onto the mould that covers the bathroom ceiling.
Moving along – the particularly interesting thing about congestion in this corridor is that we as a society has just invested in:
- The Northern Busway, which provides an extraordinarily successful (given the prevailing lack of development around stations) and relatively congestion-free public transport corridor that runs in parallel with SH1. From what I can tell (back of envelope numbers) the Northern Express is now operating at close to full cost recovery. Further only being a fraction of the vehicles that cross the bridge, around a third of all people heading southbound in the morning peak do so on a bus. This graph from ARTA is a couple of years old but shows how quickly the situation is changing thanks to developments like the busway. There is still a lot we can do to further improve the bus experience for Aucklanders, especially on the city side through improved bus lanes and facilities.
- The Western Ring Route, which (when complete) will provide an alternative route for some vehicle trips. From what I know, transport modelling predicts a drop of about 5,000-10,000 vpd on the bridge when Waterview is complete. As such, the WRR could reduce vehicle volumes on the existing Harbour Bridge by around 5%. Not huge, but probably enough to noticeably reduce congestion.
Conclusion #1: Together the Northern Busway and the Western Ring Route are the main congestion safety valves that Auckland needs across the Waitemata.
Second, we accept that the clip-ons may fall off when a continuous line of fully laden 40+ tonne trucks comes to a grinding halt on the bridge while being buffeted by hurricane force winds. Yes, the next time we have a hurricane that prompts some kind of lemming like heavy vehicle pilgrimage (which for some reason ends up stopping on the Harbour Bridge) then the clip-ons may become pontoons. But does it necessarily follow that we should spend $5 billion on a new crossing? Not really, if you consider the following options as being alternatives to a new crossing:
- Ban heavy vehicles from using the bridge in high winds; or
- Restrict heavy vehicles to using the main span of the bridge; or
- Require heavy vehicles to divert via the aforementioned Western Ring Route.
Some of these management techniques have already been used in the past so they wouldn’t be something new. Conclusion #2: Ultimately there seems to be at least three more effective ways of extending the life of the clip-ons (perhaps indefinitely) that helps us to avoid spending $5 billion on another crossing.
Third but not least, we come to the suggestion that “it’s always been in the plans.” To understand this argument we tried having a look at the plans. The latest ones came out in 2010, when NZTA last considered the merits of the project. This included preparing some detailed drawings of how it could work and a Business Case that analysed the costs and benefits of a bridge option and a tunnel option. The cost-benefit ratio for the two options are shown in the box below, which is found on page 65 of the business case document:
With a capital cost of close to $5 billion for the tunnel option, this would mean a return of around $1.5 billion excluding agglomeration benefits or $2 billion including them (using undiscounted figures). So pretty much the same as getting $3-3.5 billion and burning it. Now you don’t have to be an economist to know that this analysis is suggesting that this project is morse code for “absurd waste of money”.
Conclusion #3: If the additional Waitemata Harbour Crossing has always been “in the plans” then we’d just respond that it damn well shouldn’t be. Or perhaps more accurately: Just because something was a bad idea in the past, doesn’t mean it will be a good idea in the future.
At this stage some of you may be thinking “case closed” – let’s strike that project off the list and move on. But wait there’s even more to this post: When reading the NZTA’s Business Case we found, how shall we say this, ”questionable” assumptions about future growth in vehicle volumes. But before going into them its time for a little pop quiz, if you are modelling traffic flows in 2010 to predict future vehicle volumes do you:
a) base it off the currently available numbers
b) ignore what actually happened and use a model to predict what the numbers were
Here are the numbers that were used which comes from page 10 of the business case:
The important thing is the 2008 numbers seem to have been generated by a traffic model, because they do not match what was actually observed. For example, the NZTA’s own numbers for 2008 say there were only a average of 154,925 vehicles per day that crossed the bridge, a difference of over 13,000. The difference in the volumes can be easily seen from the graph below, which shows actual traffic volumes (green) and predicted traffic volumes (red).
There’s a couple of interesting things about this graph: The first (and most obvious) is that the modelled traffic volumes are approximately 10% higher than the actual volumes, even before the Business Case was released in 2010. Basically, the Business Case appears to be re-writing history by using traffic volumes that are higher than what was actually observed. Bizarre eh?
Personally, I would have thought that where you had a transport model that was predicting volumes that were 10% higher than the actual observed volumes then that would be reason to re-calibrate the model so that it more closely matched actual volumes, certainly before you did absolutely anything else with the outputs – let alone argue for us to spend $5 billion. Nevertheless, it seems (from what we can tell reading the Business Case) that the red line above was the one used in calculations of benefit-cost ratios, despite actual data showing that it was 10% off the mark from the outset (NB: A 10% difference in vehicle volumes makes a huge difference to congestion reduction benefits).
The next interesting thing is that based on the red line NZTA has (somehow) concluded that the next Waitemata Harbour Crossing is needed between 2020-2030, at which point they were expecting between 188,000-200,000 vehicles per day (vpd) over the bridge. If we take the mid-point of this range as defining the “critical threshold” then we can conclude that the current crossing arrangements is maxed out around 194,000 vpd. The figure below illustrates this critical threshold as the black dashed line. We have also extended the actual volumes (green) using the modeled traffic volumes (dashed green line). The latter sort of shows what you might expect to happen to vehicle volumes in the event that we returned to the modeled “trend” for the next 30 years.
We can see that even by 2041 the dashed green line stays below the dashed black line, i.e. we have not come close to hitting the “critical threshold” even by 2041. Stated simply, the reduction in vehicle volumes observed on the Harbour Bridge in the last 5 years or so seems to have bought us at least another 20 years when it comes to developing an additional Waitemata Harbour Crossing. Why so much time? Well, because it will take us ten years to get back to the level we were 5-10 years ago. That’s why we now have so much time and why this project, if it’s needed at all, does not seem to be “urgent”.
With all this in mind I can’t understand why some people at NZTA (and certain politicians on the North Shore) seem to be pushing for an additional Waitemata Harbour Crossing to be constructed soon, like between 2020-2030. Surely the smartest thing to do before pushing this project along is to:
- Wait until we have completed a few projects that may impact on the need for this crossing; and
- Recalibrate the model and issue an updated business case incorporating revised traffic growth assumptions?
At this stage, not only does another road-based crossing of the Waitemata Harbour seem like an ineffective way to address the issues put forward, it also seems like it’s nowhere near as urgent as some people make out. I have no problem with long term planning for another crossing, but let’s not kid ourselves that it’s needed in the next 30 years. By crikey.
A previous post by Patrick highlighted his concerns about the phrase “multi-modal”, something that I want to explore further. Patrick’s general argument is that we “talk the good talk” about multi-modalism (is that even a word?) but in reality what we have built over and over again is “mono-modalism”.
So I guess the question I want to ask the government is how sincere are they really about Multi-Modality? I agree a truly multi modal Auckland would be a great improvement but successive governments have deviated very little from a highway dominant policy and the current one has greatly accelerated it, and therefore increased our Mono-Modality. The Government Policy Statement makes it very hard to get funding from NZTA for any mode at all other than state highways, in fact it seems designed to enable motorways to get funding no matter how poor their cost benefit analyses. So under this government the share of Land Transport funding going to anything other than state highways has shrunk. And now they are planning to make it even more difficult for the local authority to make its own investments that may differ from this bias.
I’m going to stick my neck out a bit further and say that while I’m a big supporter of the idea of a multi-modal system, I’m not really much of a fan of “multi-modal projects”. They just seem to turn into ways of justifying a lot of spending on roads now, with perhaps a little bit for public transport in the very distant future.
A classic example of this is the “Additional Waitemata Harbour Crossing” project. By far the most expensive project proposed for Auckland in the next 30 years (estimated cost is north of $5 billion!), it is another harbour tunnel which doesn’t add any capacity to the roading system anywhere except between the Esmonde Road interchange and spaghetti junction. Because of this, we’re basically spending $5 billion to make it easier for people to drive into the city centre – even though pretty much every other part of Auckland’s policies and strategies scream out that we want to reduce the car focus of the very same area.
Perhaps to appease those screaming out “why on earth would you want to do something so stupid?” the Auckland Plan says that there’ll be a rail line in the tunnel – the first step towards extending rail to the North Shore. Or at the very least the tunnel will be “future proofed” for rail so that it can be built at some point in the future. Here’s a lovely map showing how the two tunnels could happily co-exist:
Of course what’s not discussed here is the impact of the new road crossing on your likely demand for public transport. Considering that around 35% of people coming over the harbour bridge in the peak times at the moment are on the bus plus most of those people will be going to destinations in the city centre, around the universities or to Newmarket, public transport must have a really excellent modeshare for “North Shore to central city” trips – I would suspect well above 50% once you count the ferries.
One of the reasons this modeshare is so high is because the alternative isn’t too flash – a slow, unreliable and congested trip in along the Northern Motorway (and its many clogged feeder roads). Go and provide a heap more lanes of roading capacity at a vast cost and you’re just about guaranteed to kill off public transport demand (at least until your expensive new road gets clogged again). This means you can’t justify the rail tunnel and therefore you’ve just ended up reinforcing your city’s car dependency.
And in a nutshell this is the problem with multi-modal projects. Because they’re looking at upgrading both the road and the public transport at the same time, they’re actually two bits of a project working against each other. The public transport project would undoubtedly generate more patronage growth if the road running in parallel to it wasn’t also being widening/duplicated/upgraded to motorway status. Similarly (though interestingly not as convincingly), the economics of the roading project would probably stack up better if everyone was forced to use it and it wasn’t having its usage undermined by a parallel PT project.
This is where multi-modal projects really miss the point of public transport investment. One of the biggest reasons to spend money on a public transport project is so you don’t need to spend vastly more on a roading project. The Northern Busway is a great example of this as it’s vastly increasing the capacity of the Northern Motorway and delayed (or completely removed) the requirement for another road-based harbour crossing. Upgrading the rail network has done the same – every passenger coming up that southern line is delaying or removing the requirement to widen the southern motorway. With multi-modal projects it seems like we identify the project that’s required to ensure we don’t need that other project, but go ahead and build both anyway.
At the end of the day, I suppose multi-modal is nice for politicians because “there’s a bit in there everyone will support”. Those who want more roads are happy, the PT crowd are happy, there might be a cycleway to keep those advocates happy – everyone wins. Except the person paying the bill who has gone and wasted a huge amount of cash on a road that’s probably not needed if the other parts of the project are done.
What Auckland needs is a proper multi-modal transport system, not a whole pile of extremely expensive “multi-modal projects” that just reinforce our car dependency. We’ve got the roading side of the system pretty much finished already.
On Twitter today, North Shore Councillor George Wood asked:
Its an interesting question but to me the answer is simple, the CRL. The reason for it comes down to demand. First up lets look at the the harbour bridge, the average number of vehicles crossing the harbour bridge today is less than it was in 2003 and that is showing no signs of changing.
The NZTA also now release monthly data about the bridge which goes back as far as September 2007 which enables us to have a bit closer look at what is happening.
So there are some changes but overall we are not seeing traffic anywhere near the peak of a few years ago. Of course some will argue that it is because the economy hasn’t been great but that doesn’t explain why so many people are now crossing by bus. In fact around 30% of people crossing the bridge at peak times do so via bus and this has seen the total number of people getting across the harbour continue to increase. Further if we think about the future demand for the crossing it also suggests that another crossing isn’t needed any time soon. This is because in 5 years the Waterview tunnels will be open and that will provide more options for people travelling to the shore which should help to take some of the pressure of the bridge.
So what about the CRL? We have seen patronage growth slow down in recent months however this is much more likely to be a temporary blip. As Peter mentioned the other day there continue to be a lot of issues plaguing the rail network and there is still a lot of capacity left to improve services, especially in the off peak. Sorting out these issues and the completion of electrification are likely to have huge impacts on both the perception and use of the rail network and the extra capacity electrification brings is projected to be all used up by 2021.
Things change further when you consider the cost to build each of these pieces of infrastructure, the CRL is expected to cost around $2.4b while another harbour crossing is expected to be over $5b. Without that extra demand it would be really stupid of us to even consider pushing a harbour crossing over the CRL. When it does come time to consider a new harbour crossing we should also consider prioritising a PT only crossing first. That would provide a really fast, congestion free trip across the harbour which would be very attractive and free up the existing bridge for those that choose to sit in traffic.
Readers of my recent post may recall that I’m no fan of the proposed second harbour crossing. That has a lot to do with the fact it would actually be our third harbour crossing, and our third motorway crossing at that. With traffic levels static on the Upper Harbour Bridge and actually declining on the Auckland Harbour Bridge it seems a little silly to be planning yet another motorway across the harbour, especially once we consider how effective the busway has been.
It’s not actually a case of fewer people crossing the harbour each day, that figure keeps climbing, it’s just that all the growth has occurred on public transport. More and more people cross the harbour each day… on a bus. This begs the question, why aren’t we planning a public transport crossing? A projected cost of more than five billion dollars for a harbour tunnel and it’s all just for cars and trucks. Something needs a rethink methinks.
The real problem with proposals like this is that they just won’t go away. No matter how poor the business case, how low the BCR (around 0.2 to 0.4 if you’re asking), no matter how damned expensive… I just can’t shake the resignation that sooner or later this motorway tunnel is going to get built anyway. All it takes is one minister to start using words like ‘policy alignment’ and ‘strategic fit’, and all the extensively researched economic evaluations aren’t worth toilet paper.
With that though in mind I went back to the drawing board and started to think about how we could really make a harbour tunnel work. If it abso-friggin-lutely has to be built come hell or high water, what can we do to make it a real bonus for Auckland? How can it also improve public transport, walking, cycling and urban design?
After all, it’s not like this megaproject couldn’t have some additional benefits. For a start the plan is for the tunnel to carry State Highway 1 though to Spaghetti Junction and leave just citybound traffic on the existing bridge. If they do this right the new tunnel would function as a bypass of the CBD, by taking all that heavy traffic and sending it underground and out of the way. With only city bound traffic on the bridge we could reallocate a pair of its lanes to buses, and without heavy freight traffic we would have enough strength in the clip-ons to add the proposed walking and cycling path.
More excitingly, without any need for a link between the bridge and the other motorways we could tear down the Victoria Park viaduct and free up that corner of the city. The remaining Victoria Park tunnel could be reused as a two-way link for traffic through to Cook St, perhaps even taking the bulk of traffic off Fanshawe St. In any case we could almost halve the number of lanes through St Mary’s Bay, if those lanes need only enough capacity to service the city streets and not the motorway.
There might even be a case for demoting the St Mary’s Bay motorway to an avenue style expressway, a sort-of western version of Tamaki Drive extending from a revitalised Fanshawe St boulevard. Auckland’s city waterfront could then stretch right across to it’s natural anchor at the foot of the bridge. I can see it now: rows of leafy trees, a stretch of waterside grass, cyclists whizzing along to the North Shore, kids eating ice creams as mums and dad watch the comings and goings of the marina and the harbour.
The plan for St Mary's Bay today. Fourteen lanes carrying city traffic and State Highway 1.
... and what it could look like if it only carried citybound traffic.
This all sounds very good, positively bucolic even… but truth be told we’re not really getting much value out of this yet. Five billion bucks to get some bus and cycle lanes on the bridge and tidy up the waterfront? To be frank that is the sort of thing we can do anyway at a much lesser cost, we don’t need a motorway tunnel for that. If we really want to get value out of a harbour tunnel it has to carry public transport, and I mean proper high capacity and fast rapid rail transit. Nothing else is going to move enough people to swing the numbers. Adding a rail line to the motorway tunnel could triple it’s carrying capacity at very little extra cost, if only some space could be found inside the same pair of tubes.
If we look at NZTA’s most recent proposals we are actually talking about some pretty big holes through the ground. One of the issues with boring a tunnel like this is that motorway lanes are basically rectangular in cross section, while tunnel bores are circular. It’s very much a case of fitting a square peg into a round hole. In this case the round hole will apparently need to be about 15.5m in diameter to fit in a square peg 12m wide and 4.5m tall.
The NZTA proposal for the harbour crossing. Two tubes like this would be tunnelled under the harbour.
That’s quite a lot of tunnel indeed, and in fact some of it ends up wasted. I’ve clarified the labels there because they are too hard to see, but the bottom right corner of the cross section is simply ‘cement stabilised backfill’. In other words that is just a mix of concrete and dirt poured back into the tunnel to hold the road deck up. Could we not put this space to better use?
Closer inspection of the cross section reveals the sorts of things you might expect in a tunnel: lights, fans, smoke extraction ducts. But underneath the road deck there is also a sump area to extract water, and a cable tunnel to carry pipes and wires across to the North Shore. That cable tunnel is actually pretty big, about 4m tall and 3.5m wide, could we fit a train through there? Probably not one of our new electric trains, they’re a bit too big and their overhead power lines need more height. But I do think a more compact light metro vehicle would fit in comfortably, particularly as they have a low floor height and get their power from between the rails instead of an overhead wire.
This picture shows a Bombardier ART driverless metro train to scale in that same cable tunnel, nestled in under the road deck. Instead of backfilling the empty space under the road, I’ve used it to relocate the cable tunnel to one side. This could also double as an emergency exit, or an access path to whatever emergency system they would have to install in the motorway tunnel anyway.
The same tunnel with a Bombardier ART light metro train under the road deck.
Basically, it seems with a little rejigging of the layout of our big harbour motorway tubes we could also fit through a light metro line to the North Shore. Given that it’s the same pair of bored tunnels, this rail crossing could be tacked on for minimal extra cost.
Now I must say I am no civil engineer and I couldn’t confirm if this is actually feasible, but a quick looks suggests that we very well could get both three motorway lanes and a driverless light metro track into what NTZA were proposing to build for the motorway alone. The benefits of this would be immense.
Three motorway lanes can carry about 6,000 vehicles an hour at best, which at our occupancy rates translates into about 7,500 people. The light metro systems in Vancouver and Kuala Lumpur currently carry about triple that on each track at peak times, and can theoretically move well over 30,000 people an hour each way.
Stacking metro tracks in under the road decks could easily quadruple the person carrying capacity of a harbour tunnel, and one can only imagine what that would do to the cost benefit ratio. If we must build a hugely expensive motoway tunnel under the harbour, then a shared motorway and metro tunnel could be just the thing to make the numbers stack up too.