Additional Harbour Crossing back on agenda

The government has announced it is restarting the process to protect the route for an a third harbour crossing that raises a huge number of questions.

Minister of Transport, Simon Bridges, has taken steps to future-proof the route for an additional Waitemata Harbour crossing in view of the rapid growth Auckland is set to undergo in the next 20 years.

“I have asked the NZ Transport Agency to recommence work on what will be a critical transport link for Auckland and the upper North Island.

“The preferred route for the additional crossing is a tunnel east of the Auckland Harbour Bridge between the Esmonde Road interchange on the North Shore, and Victoria Park Tunnel and Central Motorway Junction in central Auckland.

“Advisors are preparing for the designation process and are putting together a business case focusing on the timing of construction and potential funding options,” Mr Bridges says.

In 2013 the Government announced its support for a tunnel in preference to a bridge.

“With increasing demands on Auckland’s transport network, the Government will continue to work closely with its local government partners to provide a resilient network and wider transport choices,” Mr Bridges says.

The NZ Transport Agency says an additional crossing is likely to cost between $4 billion and $6 billion, and is likely to be needed between 2025 and 2030. A construction start date will depend on a number of factors, including the rate of freight and traffic growth.

Mr Bridges says that the additional Waitemata Harbour crossing will work in conjunction with the existing Auckland Harbour Bridge.

The business case will look at a range of public transport options, including heavy rail. The NZ Transport Agency and Auckland Transport will be working together on this part of the project, including any necessary route protection for public transport.

“The Government knows that investment in all modes of transport will ease congestion and bring lasting benefits for Auckland and for New Zealand as a whole,” Mr Bridges says.

The NZTA last studied an additional crossing five years ago and the reports from that study are available here. The questions I have are in no particular order.

With construction depending on factors such as traffic growth, will the new business case take into account the actual traffic volumes from the last 8+ years. After almost 50 years on constant increases, traffic volumes fell after 2006 and have been so stubbornly flat that they are still less than they were in 2003. Not only did the previous business case – produced in 2010 – predict growth that hasn’t materialised but they also used a model to predict the volume for the starting year of their prediction (2008) which was well above the observed actual volumes.

Related, what will be the employment and traffic volume targets the project must achieve. After all if the City Rail Link is going to have bogus targets foist upon it then why shouldn’t the single most expensive project we’ve ever considered.

With the project costing between $4 and $6 billion how will we pay for it. To put things in perspective we currently spend about $3.4 billion on transport per year for the entire nation and that includes costs for state highways, NZTA contributions towards local roads, road policing, and of course NZTA contributions towards public transport. Within that budget we spend $1 to $1.4 billion on state highway improvements. In short an AWHC would suck up massive amounts of cash and that would impact on a huge numbers of projects from all around the country. Even if built as a PPP the ongoing payments would likely cripple our transport budgets for decades. As an example Transmission Gully which is costing around $850 million will have repayments once it opens of about $125 million a year. AWHC would be significantly more than that.

Will the business case achieve a Benefit Cost Ratio of greater than the 0.3 it did last time (Answer: presumably it will because of the changes since then to the NZTA’s Economic Evaluation Model allowing for a longer assessment period and reduced discount rate – still won’t be above 1 though)

It’s all very well talking about a horrifically expensive tunnel under the harbour but what constantly seems to be ignored is what happens on either end of the tunnel. Studies prior to the 2010 one have talked about how any new crossing would also require major expansions to the Northern Motorway to cope with the increased capacity thrown at. How much is it going to cost to duplicate SH1 to Albany and beyond? If not then we just get this situation.

What impact will the $4 billion we’ve been spending to create the Western Ring Route have on traffic and travel behaviour. At the very least we should probably be waiting till after that work is completed and traffic volumes have settled down before we do any analysis of traffic demand over the harbour.

Regardless of how much it costs or what the benefits are one fact that can’t be ignored is that this project will have major impacts on the environment it passes through. It effectively creates a new motorway out in Shoal Bay with all the red hatched parts in the images below being reclamation and the blue parts being viaducts. I wonder what the likes of the Herald’s John Roughan will say about – note:  I still don’t think he’s admitted he was wrong about the Northern Busway.

Further if some of the residents of Northcote got so upset about the idea of Skypath, I wonder what they’ll think of having a mini spaghetti junction on their doorstep. Even more so when they realise that the two square boxes on the image above where the new lanes change from tan to purple colour (to the right of the 1 symbol) are 35m high (~10 storey) ventilation stacks for the exhaust fumes inside the tunnel. There is also one on the city side next to the current Air NZ building (below).

One mini positive is that the government are at least saying the business case will consider a rail crossing however in my mind the NZTA also need to assess options that involve building a PT only crossing first. A dedicated PT crossing along with Skypath are the real missing modes across the harbour. This is especially important given the huge growth we’re seeing in bus passengers from the shore and in the morning we’re seeing up to 30-40% of people crossing on a bus – up from 18% in 2001. This growth in PT is likely to continue for some time yet, especially once the new network eventually makes PT much more useful to a wider variety of people. One risk is I suspect there are quite a few people behind the scenes that will think an acceptable solution to PT across the harbour is just to leave it on the existing bridge.

Overall route protection itself isn’t a bad thing but any suggestion that this is project is needed any time soon is fanciful thinking. There are far greater priorities in Auckland such as the CRL and significant upgrades to PT in many other areas. The government should be focusing on getting those projects consented and underway first.

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