AWHC: Time to re-consider a bridge?

As regular readers will know, we’re not exactly big fans of another road-based harbour crossing being a priority. We believe that after Skypath, the next crossing should be a rapid-transit-only crossing, providing those travelling to and from the North Shore with a complete and attractive alternative to the current bridge. It could be designed to leave space so that a future road crossing could be built if still needed.

Instead, the current most likely outcome is that we’ll spend $4-6 billion on a tunnel and massive interchanges at each end. And yet, because of changes they’ll make to how the existing bridge is used, it’s likely the extra crossing won’t even provide any additional capacity to the road network. About the best we’ll get is some bus lanes – AT and the NZTA have been suggesting that light rail could possibly go over the existing bridge, but my understanding based on conversations with various staff is that this is unlikely to be a realistic option.

So if we’re going to build a road crossing that doesn’t actually do much, perhaps it’s time to reconsider a cheaper bridge option. According to the last study by NZTA in 2010, a bridge option would be around $1.4 billion cheaper. That level of saving is nothing to be sneezed at, after all the entire cost of the Waterview tunnels project is $1.4 billion!

A bridge would also be considerably cheaper to operate and maintain – about $4m per year vs $20m per year (in 2010 $). Again $16m a year, every year, is significant. That’s roughly how much public subsidy is paid each year to top up fare revenue on the North Shore bus network.

The main reason for selecting a tunnel rather than a bridge was the result of public feedback around 5 years ago on the council’s Auckland Plan, and I’d say most of that feedback took place without considering the huge cost impact of their decision. One of the main reasons for this is the view it would obviously represent a dramatic visual change, which many people would be fearful of.

But would a bridge option be all that bad? Bridges all over the world can be some of the most stunning and iconic features of cities. Designed well they are more than just function.

Below are some of the renders from the NZTA study, so take a look for yourself. We were reminded of these when leafing through some of the obscure old reports so I wonder if most people even knew this was an option?

AWHC Bridge option 3

We quite like the design, the triangular cable towers are vaguely reminiscent of volcanic cones or perhaps sails on the harbour. In any case they have a monumental look. Cable stayed bridges are quite popular these days, as they are strong, stable and self-supporting during construction, which makes them fast and cheap to build. Of course there would be other types of bridges that could work: a grand suspension bridge like the famous Golden Gate, another steel arch bridge, a very simple concrete girder or maybe something wild and unusual.

AWHC Bridge option 1

Thinking about this, we think there are some other potential benefits of a second bridge, beyond the big construction cost saving and the cheaper operations and maintenance over time.

Firstly, it would be easy to provide road and rail on the same bridge, something that is difficult and expensive to do in a tunnel. We know that Auckland Transport are currently looking at rapid transit options to the North Shore. Given they are considering light rail across the isthmus and the airport, it wouldn’t be a stretch to imagine that they would consider it here too? And why not, light rail only takes up as much room as a traffic lane each way, and it can handle almost any grade you would want on a motorway bridge. So for the minimal cost of adding two lanes for light rail to the six lanes of motorway you could literally double the people carrying capacity of the crossing. It would also tie in nicely with the current plans for the isthmus which would see light rail along Fanshawe St to Wynyard.

There is also the possibility that you don’t need to add much at all. The NZTA designs below show a box section holding up the road deck. With a little tweaking to the design it could probably be big enough to run a rail line through each way. A rail deck inside the bridge structure is pretty common in bridges around the world, perhaps a double deck bridge is an efficient solution for Auckland?

97883a04-577a-48d6-a2de-921cfa7ec105

Secondly, a new bridge would give a nice and more direct walking and cycling link, as we can see in the picture below. While we agree the Skypath is an excellent value retrofit and should proceed asap, having separate walking and cycling links on a more direct alignment would be even better in the long term. We would obviously expect walking and cycling connections to be a little wider than shown in the image below though.

AWHC Bridge option 2

Thirdly, bridges avoid a lot of the problems that tunnels can have with things like vehicle fires, water leaks and dangerous goods spills. Melbourne has had a pair of under-river tunnels since the early 2000s and it has experienced all three kinds of incidents, with many lives lost in one bad fire down in the tunnel.

2nd Harbour Bridge top view

So, could a relatively cheap and efficient new bridge with a mix of traffic lanes, light rail, walking and cycling be the right answer for the North Shore? Such a crossing might come in under $3 billion, less than half some of the recent estimates for doing motorway and rail in tunnels. But there might be some further savings to be had too. In the renders below we can see that the bridge itself is a fairly slender and graceful structure. But the real impact, and much of the cost, of the harbour crossing plans come from the connections either side, including what amounts to a new Spaghetti Junction in St Mary’s Bay complete with three additional tunnels under Victoria Park and a similar tangle of ramps and reclamation at Northcote Point though to Akoranga.

2nd Harbour Bridge top view - VP

If the crazy plan to dump six lanes of bridge traffic onto Cook St was dropped, they could drop the duplicate Victoria Park tunnel and a mess of associated ramps and structures approaching it. The existing Victoria Park tunnel could be reconfigured into one lane each way to Cook St by adding a central fire wall, instead of building a second one next to it to get three lanes each way to the middle of town. This would improve connectivity to midtown while providing a reasonable, rather than insane, amount of vehicular capacity. Not only would this save the city from drowning in traffic that has nowhere to go from Cook St, it would also save a further half billion or so from the cost and reduce the amount of structures and reclamation on the waterfront.

A second advantage of new bridge with light rail would be the ability to drop the proposed busway additions on the old bridge. That sounds crazy coming from this blog, but you have to ask why you would need both a busway and railway next to each other when rail alone can do the job well. If you dig through the plans you can see NZTA have designed an elaborate series of busway lanes and flyovers either side of the harbour bridge, in addition to the rail designation (clearly they didn’t put much faith in rail ever actually happening). Dropping the busway links in favour of light rail only would likewise cut out a lot of concrete, and hundreds of millions of costs.

There are some further benefits of value engineering out the spurious ramps and links. With less linkages you need to reclaim less harbour and build fewer flyovers, but you’d also get to detune some of the worst bits we already have. Do the crossing right and St Marys Bay could be turned from eleven lanes of motorway into a six lane waterfront boulevard through to Fanshawe St and Cook St. It might have more in common with Tamaki Drive than Spaghetti Junction.

So what about it Auckland? Would we be happy with a new bridge if it meant traffic, rail and people could be accommodated together while saving billions of dollars and reducing the impacts on the waterfront areas? Is there a “lean and mean” road solution that could be funded and built earlier while also giving people the rapid transit crossing they want?

To finish we just have to ask, why was this option dropped so readily? Given the potential to save billions and get better outcomes shouldn’t we at least have a thorough discussion?

NZTA and a Rail Harbour Crossing

The issue of another road crossing of the harbour has been one we’ve discussed for quite some time. It’s a project that many Aucklanders like to think makes sense but that when you look deeply at the details it’s not so clear it’s a good idea. Without going over everything again – you can read some of our old posts on the subject – the project is hugely expensive and yet doesn’t actually appear to provide that much benefit.

In fact the impact seems to range from actually make some key things worse – to at best not actually changing all that much. It is expected that any road tunnel would plug in directly to the Central Motorway Junction and therefore only be used by those travelling through the city or to the connections with Grafton Gully or West Auckland. That would leave the existing Harbour Bridge as a giant off-ramp.

In fact it is actually likely to undermine many of the goals the council have been striving to achieve such as increased use of public transport and a more people friendly city centre. Both will be much more difficult to achieve if a firehose of traffic is turned on to the CBD.

Westconnex

From Sydney but appropriate here too

If spending $4-6 billion to undermine your city’s goals seems stupid, equally so is the more likely alternative version from the NZTA.

One thing that is widely accepted is the need to improve the rapid transit options across the harbour. The Northern Busway is fantastic however it’s missing any priority across the bridge despite buses carrying around 40% of the people going over it AM peak. They would use AWHC to finally dedicate some space on the bridge for PT but the actual number of vehicle lanes across the harbour will be about the same as they are now. In that case we end up spending a huge amount of money to add no vehicle capacity and just to add some bus lanes. It begs the question of why bother, why not just leave the bridge as is and build a better and cheaper dedicated PT crossing.

Because of the need to improve rapid transit options we’ve long advocated for a rail first option to be considered. This doesn’t mean we can’t build road tunnels in the future should they be needed but along with Skypath, rail tunnels more cheaply, directly and immediately address the modes missing across the harbour.

Skypath Consent - From Westhaven

And we’re not the only ones. The Campaign for Better Transport have created a petition calling for a rail only option to be considered. It’s managed to pick up a good amount of media coverage and forced some interesting statements from the NZTA and the mayor. Reading between the lines and combined with what we’ve heard it highlights a concerning situation.

First up from the North Shore times

But NZTA Auckland regional director Ernst Zollner says Pitches is “misleading” people.

Rail hasn’t been ruled-out, he says.

Although harbour crossing route protection work is underway, NZTA doesn’t know precisely when it will be needed or what form it will take, Zollner says.

Previous proposed plans include twin vehicle tunnels future-proofed for rail.

….

An Auckland Transport spokesman says a public transport study anticipating future growth will be completed mid next year.

The agency which manages local roading connected to NZTA’s motorway network, says it’s investigating how public transport options would integrate into future connections.

Auckland Mayor Len Brown says central government has committed to starting a second harbour crossing within seven years.

Rail will either be part of the second crossing or complementary to it, Brown says.

Another proposal would see harbour bridge lanes repurposed to carry light rail to and from the North Shore.

The NZTA are intending to lodge designation documents for the crossing this year. That means there is no way they can be intending to include rail options within their plans. This matches with what we’ve heard elsewhere that they intend on building their road tunnels and leave the rail options to AT/council to sort out as a separate project. Despite what the mayor or AT say there is no way they’ll be able to justify spending huge sums of money on a rail crossing to the shore if we’ve just spent $4-6 billion on a road crossing.

The second piece is from the Central Leader

“At that point in time they either will build the capability for rail within the tunnels or as correlative part of it,” Brown said.

But the New Zealand Transport Agency (NZTA) which constructs state highways says no decisions have been made.

Auckland regional director Ernst Zollner said NZTA and local agency Auckland Transport were currently working to protect a future route for an additional harbour crossing.

“While we don’t yet know when it will be required, and precisely what form it will take, in a rapidly growing region it’s essential that we protect and keep our future options open,” he said.

The northern busway serving the suburbs north of the bridge had been a huge success, and one of the benefits of a second crossing would be to continue it across the harbour.

“(It) could then also be used for rail or other innovative public transport options in future,” Zollner said.

Again this all but confirms there is no intention to build rail as part of the next harbour crossing. At best it is happening as an afterthought and only once we’ve sunk billions into some road tunnels and massively upgrading the motorways either side – something the NZTA are being very quiet about. I suspect the only reason they’ll even consider having light rail on the bridge is that after they’ve built the road tunnels they’ll revoke the state highway designation and hang the bridge asking with its expensive maintenance costs over to AT.

The AWHC appears to be a classic case of the same gung-ho roads first approach that has left Auckland in such a mess for so many decades. So let’s build a great PT crossing first and then see if we still need more traffic lanes across the harbour.

Will the proposed Waitemata Harbour Crossing be good for drivers?

There are many reasons to be concerned about the plan to add more road lanes across Auckland’s Waitemata Harbour: from the extreme cost of building such big tunnels and interchanges [$5-$6 billion and four times as much as just building rail tunnels], to the undesirable flooding of city streets and North Shore local roads with even more cars, to the increase in air pollution and carbon emission this will create, the loss of valuable city land to expanded on and off ramps and parking structures, to the impact on the harbour of exhaust stacks and a supersized motorway on the Shore, to the pressure this will put on the rest of the motorway system particularly through the narrow throat of Spaghetti Junction. It is both the most expensive and least efficient way to add capacity across this route, and if resilience is the aim then the double-down on reliance the motorway system rather works against this. This one project will simply crowd out any other changes we could make of scale in Auckland or the country for years; yet it changes almost nothing; it simply enables more vehicles to travel across a short point in the middle of the city, yet this is by no means an obviously good thing: The list of unwanted outcomes from the current proposal is so extensive that the benefits had better be so extraordinary and so absolutely certain in order to balance them all.

But perhaps there is no greater reason to not do it than that it simply won’t improve things for drivers.

Really? How can this be? As well the obvious problem with this project that it will add super capacity for a short stretch of the motorway network and therefore just shifts any bottleneck to the next constriction, particularly the extremely difficult to expand CMJ or Spaghetti Junction, there’s also a bigger structural problem with building more roads to fight traffic congestion. It can’t work. We all have experienced being stuck in traffic on a motorway and sat there wishing if only the authorities had just built an extra lane all would be sweet, well it would, wouldn’t it? However the evidence from all round the world shows that while that may help for a little while it never lasts, especially in a thriving city and especially if these extension starve the alternatives of funding, condemning ever more people to vehicle trips on our roads. Soon we’re stuck again wishing for another few billions worth of extra lanes all over again.

I-10 Katy Freeway

Here’s how it works; each new lane or route simply incentivises new vehicle journeys that weren’t made before; a well known phenomenon called induced demand. Road building is also traffic building, the more we invest in roads the more traffic and driving we get, and not just on the new road; everywhere. Traffic congestion is, of course, simply too much traffic, too much driving. Take for example the I-10 in Houston, the Katy Freeway. In that famously auto-dependent city they freely spent Federal money and local taxes disproportionately on just one way to try to beat traffic congestion, the supply side: ever more tarmac [Houstonians can boast the greatest spend per capita on freeways in the US]. The I-10 which began at six to eight lanes has just had its latest ‘upgrade’ to no fewer than 26 lanes! That ought to be more than enough in a flat city with multiple routes and only half the population Los Angeles. So what happened? According to recent analysis it has made driving this route significantly worse.

Traveling out I-10 is now 33% worse – almost 18 more minutes of your time – than it was before we spent $2.8 billion to subsidize land speculation and encourage more driving.

But hang on, those trips must need to be made, right, or people wouldn’t make them. Well in the absence of direct pricing it is hard to know exactly how valuable these new trips are. So first they really ought to price routes like the I-10 properly to reduce unnecessary journeys clogging up the valuable ones, like the truckies and trades [it is partially tolled now]. But the real problem in cities like Houston is the absence of any useful alternatives to driving [an earlier extension of I-10 took out an existing rail line!]. Providing those alternatives is how congestion is best dealt with. Not completely solved of course, that can only happen by collapse of the city economy like in Detroit, and no-one wants that solution. But traffic congestion can be made both manageable and, for many, no longer an issue, by providing them with attractive alternative options. And in turn this frees up the roads sufficiently for those who have to or prefer to drive. Especially when this is done in conjunction with direct price signals- road pricing; tolls or network or cordon charges.

Houston may be forever too far gone down this hopeless road but that doesn’t mean we have to follow it. Here is a description of the same problem in Sydney, with the solution:

Most people will take whichever transport option is fastest. They don’t care about the mode. If public transport is quicker they’ll catch a train or a bus, freeing up road space. If driving is quicker, they’ll jump in their car, adding to road congestion. In this way, public transport speeds determine road speeds. The upshot is that increasing public transport speeds is one of the best options available to governments and communities wanting to reduce road traffic congestion.

This is called the Nash Equilibrium [I would rather say better than faster; there are a number of variables including speed that inform our choices];

This relationship is one of the key mechanisms that make city systems tick. It is basic microeconomics, people shifting between two different options until there is no advantage in shifting and equilibrium is found. We can see this relationship in data sets that make comparisons between international cities. Cities with faster public transport speeds generally have faster road speeds.

Which brings us to the Waitemata Harbour. It currently has 13 general traffic lanes across two bridges, one walking and cycling lane on the upper harbour bridge, and some ferry services generally not competing with these crossings. The Harbour Bridge carries increasing numbers of buses from the hugely successful Northern Busway, the very success of which exactly proves the theory of the equilibrium described by Dr Ziebots above. In the morning peak the buses carry around 40% of the people without even a single dedicated lane on the bridge itself. And it is all the people using the busway that allow the traffic lanes to move at all. In fact NZTA argue that one of the main reasons for building a new crossing is the numbers and the size of the buses now using the current one.

The Upper Harbour Bridge is about become significantly busier because of the multiple billions being spent on the Waterview connection between SH20 and SH16, the widening of SH16, and the bigger interchange between SH81 and SH1 on the Shore. These huge motorway expansions will generate more traffic of course, but also will provide an alternative to driving across the lower Harbour Bridge.

What is missing anywhere between the North Shore and the city is a Rapid Transit alternative to these road lanes. Like Sydney always has had.

Sydney Harbour am peak

It is its [Sydney Harbour Bridge] multi-modality that makes it truly impressive, some 73% of the people entering Sydney on the Bridge from the Shore at this time are doing so on just one of the train lines and one bus lane; a fraction of the width of the whole structure. So not only does it shame our Harbour bridge aesthetically it completely kills it for efficiency too.

Auckland’s bridge was always only ever designed for road traffic, and should be left that way, the clear way forward is to add the missing Rapid Transit route as the next major additional crossing [after adding the SkyPath to the existing bridge].

In 1992 it  [Sydney Harbour Bridge] was supplemented by a pair of two lane road tunnels that up the cross harbour tally for this mode to match the number coming over by train [bridge plus tunnels = 12 traffic lanes], but that wasn’t done until the population of the city had hit 3.7 million. The high capacity systems on the bridge saved the people of Sydney and Australia from spending huge sums on additional crossings and delayed the date they were deemed necessary by many decades. But anyway, because the additional crossing is just road lanes it only adds around 10% extra capacity to the bridge. To think that the government here and NZTA are seriously proposing to spend multiple billions in building a third Harbour Crossing in Auckland with the population only at 1.5m, but not only that but they are planning to build more capacity for the least efficient mode; more traffic lanes.

The good people at NZTA of course know this, but we just seem stuck in a bad habit of road building in a similar way as Houston is, because the money for motorway building comes from central government some people believe this makes it free, in a similar way that the highways in the US are largely funded by the Federal government, unlike public transport, which is more locally funded [Known as ‘path dependency’ and is well covered in the academic literature: Imran, Pearce 2014]. This means the pressure to evaluate the effectiveness of motorways over the alternatives is much weaker. Here is a slide from an NZTA presentation proudly proclaiming how much more traffic this massive project will generate:

AWHC - Induced Demand

Of course this growth can be met by a parallel Rapid Transit system instead. The success of the Busway here and the enormous uptake of the recently improved Rail Network show that Aucklanders are the same as city dwellers everywhere and will use good Transit systems when they get the chance. And two much smaller and therefore cheaper train tunnels have much greater capacity than the proposed six traffic tunnels. Twice as much in fact: the equivalent of twelve lanes and without adding a single car to city streets. Furthermore converting the Busway to a rail system, which is entirely possible, and depending on the system may even be quick and easy, means that buses can be completely removed from bridge freeing up more capacity there for general traffic; cars and trucks:

  • Removing buses from the existing bridge would free up some capacity. 200 buses per peak hour ~= 1,000 cars ~= 60% capacity of a traffic lane. So a dedicated PT crossing provides car users with an extra lane (once you account for reverse direction). Not huge, but not negligible either.
  • Mode shift: by providing a fast and more direct alternative route you will get mode shift, providing more space to the cars that remain. So you have more vehicle capacity and less demand = a real congestion benefit.

So compared to a new road tunnel where both crossings would need to be tolled, and simply generate more competing traffic for drivers through the whole city, the dedicated PT option would seem to be better even for motorists. The better, faster, and more attractive the Rapid Transit route the freer the driving route will remain; with more people choosing the car-free option: The higher the Transit utility; the higher the driving utility.

Of course while a rail crossing will be considerably cheaper to build than a road crossing it still needs a network either side of the harbour to make it useful. Are there good options for this? In fact there are a number of very good options, all with varying advantages and disadvantages that need serious investigation. And it is important to remember by the time this project is being built the public transit networks in Auckland will be considerably more mature. The City Rail Link will have transformed the newly electrified rail network to a central role in the city, it will quickly have doubled from 2015’s 15 million annual trips to 30 million and more. The New Bus Network will be functioning and with the new integrated zonal fare system meaning people will be used to transferring across routes and modes to speed through the city. The increase in bus numbers and population will make driving in the city less functional. There will certainly many tens of thousands more people in the city without their car, many with business or other reasons to travel across to the Shore.  And importantly there will almost certainly be a new Light Rail system running from the central isthmus down Queen St and terminating downtown.

The quickest and cheapest to build will probably be to take the city Light Rail system through Wynyard Quarter and across the harbour, as outlined by Matt here. The busway can be most easily converted for this technology, as it is already designed for it. Furthermore being the only rail system that can run on streets it can also most easily include branches to Takapuna and even Milford to the east, and from Onewa up to Glenfield. This also has the advantage of balancing the existing city-side routes, unlocking a downtown terminus, not unlike the CRL does for the rail network.

What a North Shore light metro network map might look like.

What a North Shore light metro network map might look like.

Higher capacity and with the great advantage of cheaper to run driverless systems are is Light Metro like the massively successful SkyTrain in Vancouver. As described for Auckland here. However like extending our current rail system to the harbour it would require a more expensive city-side tunnel to Aotea Station for connection to city network. We know work has been done to prepare Aotea station for this possibility. Matt has also explored other variations here.

Light Metro North & Northwest

Perhaps the best answer for both the near term and the long term is to build tunnels that can take our new Light Rail vehicles for the years ahead but are also capable of being converted to the higher capacity Light Metro when the demand builds so much to justify the further investment of the city tunnel between Wynyard and Aotea Station. Bearing in mind the LR vehicles AT are planning for are high capacity [450pax ] and they can run in the cross harbour tunnels and the busway at very high frequencies. And that Light Metro systems can use track geometries much closer to LR than can conventional rail systems.

So in summary, the bane of the motorist and the commercial driver, traffic congestion, is best dealt with on the demand-side as well as the supply-side. We have spent 60 years just supplying more tarmac, and now it is time to get on with addressing the demand side: Building quality alternatives and providing clear incentives to fine-tune peoples choices.

And, just like road building, investing in quality Rapid Transit will grow the demand for more of it. It will also shift land use, incentivising agglomeration economies and greater intensification around transport nodes, as well as individual habits to suit this option more. What we feed, with infrastructure investment, grows. And vitally, inducing this sort of movement instead of driving is entirely consistent with other the demands of this century; especially our country’s new commitments to reduce our carbon emissions, and the use of our own abundant and renewably generated energy.

This project is both so expensive and potentially so valuable or so damaging that it needs a fully informed public debate about the possibilities. Gone are the days that NZTA can just keep building what its used to without real analysis of all alternatives, or that a politically expedient option sails by without serious evaluation. Because it can be transformed into a truly great asset for the city and the nation on this important route from the eye-wateringly expensive and clearly dubious idea from last century that it is now.

What’s clearly missing from this picture, especially once Light Rail fills ‘The Void’, and some form of rail goes to the airport?:

CRL Outline-Train-Plan-31July2014

Body without a head: Official post CRL rail running pattern

The Original Harbour Bridge

If you follow us on Facebook or Twitter then you may have seen some of these the other day. If you haven’t, here is a collection of some great old colour photos of the Auckland Harbour Bridge and St Mary’s Bay before they both got fatter with more traffic lanes. The images come from Denis Wilford and were taken between 1960 and 1964. It always amazes me just how slender the bridge looked back then before the clip ons and also how much space there still was around St Mary’s Bay even with the road rammed through it. In 1964 the bridge had traffic of around 22,000 vehicles per day, by comparison at its peak in 2006 it carried almost 169,000 vehicles.

The Auckland Harbour Bridge from the southern end – 1964

The Auckland Harbour Bridge from the air, with Birkenhead, Devonport and Takapuna. The Hauraki Gulf beyond – 1963

The Auckland Harbour Bridge from the air, with Birkenhead beyond and the Westhaven Marina in the foreground – 1963

The Auckland Harbour Bridge from London St – 1961

The Auckland Harbour Bridge with Auckland City beyond – 1961

On the way over the Auckland Harbour Bridge, travelling north – 1960

On the way over the bridge, travelling north, looking over to Auckland City and Westhaven Marina – 1960

The motorway from downtown Auckland City to the Auckland Harbour Bridge – 1960

The motorway from downtown Auckland City to the Auckland Harbour Bridge – 1964

Notes from Sydney: Harbour Crossings

Thoughts of Sydney are inseparable from images of its harbour:

SYDNEY_5241

It’s naturally beautiful, but also much of what has been added around the harbour increases its appeal, particularly the Opera House and the Bridge:

SYDNEY_6100

The bridge is not only beautiful, and massively over-engineered, but also is an impressive multitasker; trains, buses, general traffic, pedestrians, people on bikes. All catered for.

SYDNEY_6171

Despite that when looking at the bridge its mostly covered with cars in terms of moving people the general traffic lanes are the least impressive of the three main modes, as shown below in the am peak hour:

Sydney Harbour am peak

It is its multi-modality that makes it truly impressive, some 73% of the people entering Sydney on the Bridge from the Shore at this time are doing so on just one of the train lines and one bus lane; a fraction of the width of the whole structure. So not only does it shame our Harbour bridge aesthetically it completely kills it for efficiency too.

The Bridge has always been impressively multi-modal as the first toll tariff shows, and it carried trains and trams from the start:

Sydney Harbour Bridge 1st tolls

In 1992 it was supplemented by a pair of two lane road tunnels that up the cross harbour tally for this mode to match the number coming over by train [bridge plus tunnels = 12 traffic lanes], but that wasn’t done until the population of the city had hit 3.7 million. The high capacity systems on the bridge saved the people of Sydney and Australia from spending huge sums on additional crossings and delayed the date they were deemed necessary by many decades. But anyway, because the additional crossing is just road lanes it only adds around 10% extra capacity to the bridge. To think that the government here and NZTA are seriously proposing to spend multiple billions in building a third Harbour Crossing in Auckland with the population only at 1.5m, but not only that but they are planning to build more capacity for the least efficient mode; more traffic lanes.

The evidence from Sydney shows that what we need to add next are the missing high capacity modes. And that we clearly aren’t using the existing bridge well enough. Our bridge was never designed to carry trains, but it does carry buses, and currently these could be given the opportunity to carry even more people more efficiently. And that very opportunity is just around the corner. In 2017 or maybe even next year the alternative Western Ring Route opens, described by NZTA like this:

The Western Ring Route comprises the SH20, 16 and 18 motorway corridors. When complete it will consist of 48km of high quality motorway linking Manukau, Auckland, Waitakere and North Shore Cities. It will provide a high quality alternative route to SH1 and the Auckland Harbour Bridge, and take unnecessary traffic away from Auckland’s CBD.

Excellent, always great to invest in systems that take unnecessary traffic away. And there is no better way to achieve this than to make the alternatives to driving so much quicker and more reliable with dedicated right-of-ways. Here is the perfect opportunity to achieve that, the opening of the WRR should be paralleled by the addition of bus lanes right across the Bridge in order to lift its overall capacity. And at the same time perhaps truck priority lanes on the sturdier central lanes should also be considered, so the most important roles of highways, moving people and freight efficiently, can be more certainly achieved. Although the need for that depends on exactly how much freight traffic shifts to the new route [as well as the rail line and trans-shipping via Northland’s new cranes: ‘New crane means fewer trucks on the highway’]. Outside of the temporary blip caused by the building of Puhoi to Warkworth [much which will be able to use the WRR] heavy traffic growth on the bridge looks like it is predominantly buses.

Meanwhile our transport agencies should be planning the next new crossing as the missing and much more efficient Rapid Transit route. Cheaper narrower tunnels to finally bring rail to the Shore; twin tracks that have the people moving capacity of 12 motorway lanes. Here: Light Rail or super efficient driverless Light Metro are clearly both great options that should be explored:

Sydney_5172

But before all of this there are of course those two much more humble modes that can add their invigorating contribution to the utility of the Bridge, walking and cycling, Skypath:

SYDNEY_6174

The famous cycle steps on the northern side, there are around 2000 bike trips a day over the bridge [despite the steps]:

SYDNEY_6145

And there they were right at the beginning:

First Crossing of Sydney Harbour Bridge. Photo by Sam Hood.

First Crossing of Sydney Harbour Bridge. Photo by Sam Hood.

Timeframe for Additional Waitemata Harbour Crossing Announced

The NZTA have recently published information on the Additional Waitemata Harbour Crossing on their website, including all of their technical reports, which are mostly from around 2010. These reports have been available elsewhere, however most people wouldn’t know they existed so it is good that NZTA have pulled them all together on the main NZTA site.

New to me are the timeframes for the project, which the NZTA have indicated are:

YearActivity
2015The Transport Minister asked the Transport Agency to take immediate steps to further develop the project. The Transport Agency will engage professional advisers to help prepare to help future proof the route.
Mid 2016NZ Transport Agency to serve Notices of Requirement for land required.
2017 to 2018Detailed business case investigations including funding options and design. Application and hearings for resource consents.
2019 to 2022Procurement stage including contract award, detailed design, land acquisition and preparation for works.
2022Estimated start of construction.
2027 to 2030Additional Waitematā Harbour Crossing opens.

This is a much more aggressive timeline than the NZTA indicated at their recent briefing on the National Land Transport Programme, where it was suggested that the tunnel was unlikely to progress beyond the designation point for at least a decade.

The project website claims that the Auckland Plan identifies the AWHC will be required between 2025 and 2030 however, as we covered in this post, there isn’t any rational justification for this based on the Preliminary Business Case, which calculated a BCR of just 0.4.

NZTA route map

The project website mentions the “bigger picture”, emphasising that more than “55% of NZ’s freight travels through the Northland, Auckland, Waikato and Bay of Plenty regions”. As Matt covered in this post though, there really is only a tiny proportion of freight originating from Northland that is destined for points south, and vice-versa. It is quite misleading to include Northland in this statistic and it is certainly no justification for the AWHC . In any case, the website doesn’t mention the Western Ring Route, which is a continuous motorway linking Manukau and Albany and is due to be completed in phases in the next few years.

I haven’t reviewed all of the technical documents, but there are a couple of things about the transport modelling report that stand out. The emphasis in the snippet below is contained in the report – it isn’t mine:

Traffic Model Report 8.4

The transport model also has this table of car parking costs as an input assumption for the BCR, on p.42 of the report:

AWHC Carparking Cost Assumptions

I asked the NZTA what the highlighted text meant, and if the parking costs were daily or hourly rates, and they had this to say:

  • The Transport and Traffic Model Report (2010) analysis used costs that are 50th percentile costs which was appropriate for that stage of the investigation.
  • This report was one of the outputs of the Preliminary Business Case which was developed to assess the bridge and tunnel options. The focus was a fair “like for like comparison” between these two options, and as such the BCRs were tailored to the level of assessment appropriate to the decisions that were required to be made at that stage.
  • Currently, no further benefit cost analysis has been completed since 2010. Several years have passed since the benefit cost analysis was completed and we anticipate the BCR will be higher now.
  • Should a designation be secured for the Additional Waitematā Harbour Crossing, the Transport Agency will move forward with a Detailed Business Case in approximately 2017-2018. This will include further investigation to evaluate the preferred option and a detailed analysis of current costs and benefits.
  • The parking costs referred to in the report reflect average daily costs and were accurate at the time the modelling was undertaken.

So it looks like the mysterious Appendix M doesn’t actually exist, and any further analysis of costs and benefits won’t take place until the six lane tunnel for general traffic has been designated. The BCR of a rail only crossing to the North Shore, which will be billions of dollars cheaper than a road crossing primarily for single occupant cars, has not been calculated. The modelled costs of parking for the CBD seem woefully underestimated, compared to current earlybird rates of $24 a day.

This is completely the wrong way to go about a project which the Minister of Transport estimates will cost between $4 billion and $6 billion. Public consultation has been pretty much non-existent. I doubt many North Shore residents realise that if the new crossing is tolled, it is likely to be a toll on both the existing bridge and the new crossing.

There has been a complete lack of analysis of the impact of the fire-hose of single occupant cars which will flood the CBD as a result of the project, and neither has the full cost of increasing the capacity of the CMJ and approaches been considered. The NZTA already have in the scope of the designation work widening the motorway from Esmonde to Northcote, but it is likely that the motorway will have to be widened further north as well. The space required for this motorway widening work will undoubtedly take precedence over any future design for mass rapid transit.

Luke did a post last year on the environmental impacts of the toll road tunnel, including ventilation stacks for exhaust fumes that will be up to 35m (10 storeys) high on both sides of the crossing and the massive amounts of reclamation required. I’m not sure why the residents of Northcote Point haven’t formed an action group yet over the impending loss of Sulphur Beach and the marina. They seem oblivious to their neighbourhood becoming a construction site for at least five years too.

And of course the fact that the tunnels might be “future-proofed” for rail means nothing in practice. The designation process should not be going ahead without a clear understanding of what the mass transit network will look like on the North Shore.

There is no urgency for the crossing either – actual traffic volumes are well below the trend envisaged in the 2010 reports:

AHB Annual Volumes to 2014 - 2

I wrote to Auckland City Councillors and asked them to stand up for what Aucklanders actually want, rather than simply acquiesce to this ill thought-out plan. The only response I got was from Cllr George Wood, who said that “I must say that Simon Bridges is committed to the AWHC” and “people north of the Waitemata want the additional crossing. We certainly don’t want wish it to be stalled.”

Does George speak for everyone on the North Shore? Does Simon Bridges? What do you think?

A Random Assortment of Charts

A random assortment of charts from data that I regularly collect but which don’t often warrant their own post.

That downward spike in fuel prices a few months ago didn’t last too long

Petrol Prices 2015-07-17

Average traffic volumes over the harbour bridge are up slightly – an increase of 0.9% over this time last year – but still below what they were a decade ago. For an explanation on why there is a new and old count see this post.

Monthly AHB - 2015-06

The road toll is creeping back up. The 12 months to the end of June were up 11% on the same time the year before. Note: back in the mid-late 1980’s it was over 800 in a year so this is an improvement but still way too many people killed and injured on our roads.

Road Toll by Month - 2015-06

Airport passenger volumes continue to increase, now over 15 million passengers a year pass through the airport. Of the 4 million international arrivals, 1.9 million are New Zealanders (I assume a similar number of departures are too).

Auckland Airport Passengers 2015-06

Wellington patronage data for June is now available and shows modest growth of 2% for the year. The strongest growth is on the rail network at just over a 4% increase in patronage.

2015-06 - WLG - Total Patronage

On the issue of rail, a year ago the Auckland rail network carried less passengers than the Wellington network however (11.4m vs 11.6m) however the huge growth in Auckland has dramatically turned the tables.

Auckland vs Wellington Rail Patronage

While still on rail, here’s the results for each month shown over a calendar year – highlighting just how much larger patronage is this year compared to previous years.

2015-06 - Monthly Patronage Calendar year

Lastly on PT, how we’re tracking against the Auckland Plan target of doubling patronage from 70 million in 2012 to 140 million in 2022 (we’re just over 78 million now). After a slow start, patronage now seems to be tracking at a similar level – albeit with a lower number – to the Auckland Plan target. If the current trend continued we’d probably end up with around 130 million trips.

2015-06 - Patronage vs Auckland Plan Target

AM peak cycling counts from 9 of ATs automated cycle counters shows numbers continue to rise.

2015-06 - AM Peak Cycle counts

Letter to NZTA

 BRITOMART JULY 15_3753
After the launch of the National Land Transport Programme in Auckland last week  I wrote the following letter to NZTA with our concerns focussed on two future projects in particular. We have already received a reply confirming engagement on the issues raised:
We are all having quite a bit of trouble taking all the transport institutions seriously over RTN designations and intentions. The failure for any action to have been taken over a route through Mangere and the Airport over the last decade, and the constant reductions of any available space for a rail ROW there, or at least one not prohibitively expensive, make all the assurances we hear increasingly hard to believe.
 
Now we are expected to have no concerns at all about a process which shows every sign of just being another massive state highway with a little pretend drawing of a train in the sump of a massive road tunnel.
 
Tommy Parker confirmed today that buses on the bridge are to be the RTN solution, ie what there is now.
 
Our view is that this puts the cart before the horse. NZTA should not be starting with a solution without any clear description of the problem. We do not see why it needs a designation over a stretch of water to analyse what may be missing across here. Although it is not the designation that is the problem, but the lack of a needs focused, creative, and open minded analysis that troubles us.
 
As to us it is clear that what is missing from the existing bridges is a real RTN route [assuming SkyPath happens]. Therefore we expect to see real exploration of what delivering rail only tunnels [or bridge] would do to shape demand here. A rail system would certainly be higher capacity than road tunnels, and, well planned, would also likely be much cheaper and stageable. Adjacent rail systems do add resilience as the TransBay Tunnels did in Loma Prieta earthquake of 1989 in San Francisco. And not do have all of the disbenefits of the massive increase in vehicle numbers throughout the whole city [congestion!] that more traffic lanes will.
 
We know than any additional road capacity here would be a total disaster for the city, which we are currently de-carring, and the CMJ which is already full, and the North Shore local roads. We also know, and NZTA almost brags about this [see below], the main outcome would be a traffic inducement on a massive scale:
 
AWHC - Induced Demand
This is ‘decide and provide’ in a bad way, a huge programme of traffic creation; $6 Billion to get people out of buses and into the driver’s seat. What ever we build across this route will be used; what an amazing opportunity to choose to shape both demand and the city in a wholly positive way.
 
However the fact that NZTA is not currently allowed to spend on rail capex, and anyway really is mainly a State Highway provider and then is not calling for any outside expertise to explore rail systems is also not encouraging:
AWHC -Route Protection scope
It is our view that both a driverless Light Metro system, or a continuation of AT’s proposed Light Rail network across the Harbour, to Takapuna and up the Busway, need to be properly explored as the next possible crossing over the harbour. As they are likely to achieve all of the aims NZTA and AT are charged with delivering for the city much more completely and at a lower cost than any additional traffic lanes and without any of the disbenefits.
 
– the economic benefits of true spatially efficient urban transport system linking the Shore to city and the isthmus RTN
– make a massive transformational shift to public transport
– real carbon and other pollution reductions of scale from a 100% electric system
– huge place benefits, including a real reduction in city car and bus numbers
– no additional massive costs on approach roads
– resilience of additional systems as well as route
 
We would like to meet with NZTA at the highest level to discuss this further.
 
We are extremely concerned that institutional momentum is building for a very very poor outcome for the city and country and are determined to improve this process.
 
We look forward to your reply,
 
kind regards
 

The Devonport-Parnell Bridge

Digging around online the other day I came across an Auckland Council Archives webpage with a series of old plans and charts on early Auckland harbour bridge and tunnel concepts. I do recommend having a poke around for fans of this sort of thing.

The one plan that really caught my eye was the one below, a 1930s concept for a suspension bridge from Devonport to Parnell.  Click this link for the full size version. 

ACC 015 - 7853-004, proposed bridge layout 1930s

Look at that: tall towers with graceful parabolas of cable holding up a long spanning slender deck. Boy I do love a good suspension bridge! And check the engineers stamp in the bottom right corner. None other than J.J. Bradfield himself, designer of both the Sydney Harbour Bridge and the connected City Circle underground rail system.

With 175 feet (54m) clearance above the water this would have had more room under it than our existing bridge, however it would have ended up on the wrong side of the modern container port. If they had built this perhaps the port would have been forced to move out by now.

The four lanes and two tram tracks sounds like just what we need today, if you could squeeze in a footpath and cycleway. Having said that, you can presume the trams would have been ripped out and the bridge converted to a six lanes all for traffic like so many bridges from that era.

I also wonder what would have become of the motorway system without the harbour bridge to Northcote Point, presumably spaghetti junction would have ended up further east and Parnell would be sliced in half by a motorway. Would we lament the swathe carved through Devonport and Bayswater the way we lament the long gone villas of Newton gully and the lost beaches at St Marys Bay, or would we simply forget like we have the City of Cork Beach? Perhaps the Eastern Motorway would have been built, perhaps instead of the Southern?

In any case, the shape of our city would have been considerably different. A reminder that new transport infrastructure shapes our future city as much as it responds to our existing one.

…and doesn’t it make our actual bridge look like an ugly bugger in comparison?

Breaking down Harbour Bridge volumes

I regularly keep track of a number of statistics about transport and one of those is traffic volumes from the NZTA. Recently I noticed an anomaly with the figures for the Auckland Harbour Bridge. Previously volumes were reported as:

  • Centre Span
  • Left Clip-On
  • Right Clip-On

The monthly data for March and the annual data for 2014 (released in March) was different, instead reporting just Northbound and Southbound traffic volumes – the annual data also included the clip-ons but not the centre span. That in itself isn’t such an issue however the total traffic volumes were quite different, even for previous months/years. An example of the difference is shown in the chart below of annual traffic volumes. You’ll also notice that the volumes are up slightly – although they are still less than they were in 2005 and in percentage terms is low considering Rapid Transit services like the busway are growing by double digit figures. The chart also includes the traffic volume predictions found in the most recent business case for another road harbour crossing.

AHB Annual Volumes to 2014

So seeking an answer for discrepancy I asked the NZTA why the figures were different. The answer is below.

The original site was a National Telemetry Site with loop detectors on the two clip-on sides and an infra-red detector over the four centre lanes. This equipment used on the centre span could not determine directionality and loops could not be used due to the steel deck (the clip-on counters are on the concrete deck north of the main span).

The Auckland Motorway Alliance (AMA) established a count site just north of the bridge some years ago to collect directional data, but it was noticed that the AMA counts and the Telemetry site counts were drifting apart. The problem was with the centre span equipment, which was missing more vehicles as time went by. Therefore, it has been decided that the data from the centre span counter was too unreliable to use.

The Telemetry site was life expired anyway, so the AMA site will become the new Telemetry site. I am told that the clip-on counters are still providing reliable data, so there is no need to decommission them.

That seems a pretty reasonable explanation however as the monthly data released so far only extends back to March 2014 I asked if any further data was available. What I received back surprised me. I did receive some extra monthly data but far more interestingly I also got two years of hourly data by direction – from 1 January 2013 to 31 December 2014. Below are some of the insights we gained from that.

First up results by the day of the week. I was quite surprised to see that traffic builds up over the course of the week with an average difference between a Monday and a Friday of over 15,000 vehicles per day. The busiest single day over that two year period was December 19, 2014 when over 200,000 vehicles crossed.

AHB Traffic by Day

Breaking that down further by time the table below shows that while Fridays have the highest overall volumes, the strongest peaks occur earlier in the week which I can only guess is due to a lot of people rushing to get home whereas on a Friday the peak is smoothed a little, perhaps from people leaving work earlier or staying at work longer socialising. You can also notice that the late night/early morning volumes over the bridge are much higher than other days of the week from people ou

AHB Traffic by Time and Day

Click to enlarge

Showing traffic volumes over the course of the average weekday we get the chart below. I was quite surprised to see that the afternoon peak was stronger than the morning peak.

AHB Traffic by Hour

The data allows us to break that down further including by direction

AHB Traffic by Hour by Direction

While volumes peak in the morning and afternoon I was interested to see how things compare on a per lane basis as the moveable barrier on the bridge means that in the peak direction there is an extra lane available. It is often stated that a single motorway lane can move about 2,000 vehicles per hour. As you can see the volumes on the Harbour bridge fall short of that and peak at around 1,700 per lane. It’s also interesting that at times when the bridge is in a 5-3 configuration that lane volumes are similar.

Note: I’ve estimated the times that the barrier is moved as I’m not 100% certain.

Lane Capacities

I suspect it will be very hard for the bridge to hit any maximum capacity as it is limited by the motorways either side of it. That is also one of the major flaws of any plans to build and additional harbour crossing. You’d have duplicate or at least widen much of SH1 to either cope with the volumes or allow the connections to be used to their potential.

Lastly it’s worth considering the role that buses now play in the Harbour Bridge. Over the two hour morning peak (7-9am) around 200 buses cross the bridge southbound yet they carry around 9,000 passengers which is well more than the bridge carries in an a single morning peak hour. That points to one of the big benefits of PT investment, it’s capacity abilities. By having a strong, congestion free route it allows us to take the edge off volumes and move many more people at a time they want to travel. Imagine the impact there would be if tomorrow all the PT users who currently cross the bridge by bus instead tried to do so by car.

Overall fascinating data so thanks to the NZTA for providing it.