Today the Auckland and the North Shore are linked by the existing Harbour Bridge and regular ferry services.  From 2017, a seamless motorway from Manukau to Albany – the Western Ring Route – will provide additional capacity for cars and trucks, reducing pressure on the Harbour Bridge. For pedestrians and cyclists the Skypath project continues through the resource consent phase.

On this page we take a closer look at what is currently being planned, and what the alternatives might look like.


Waitemata Harbour Crossing Study

In 2008, the Government run New Zealand Transport Agency (NZTA) commissioned the “Waitemata Harbour Crossing Study” to evaluate short-listed options for an additional harbour crossing.  These three options were:

  1. A ‘passenger only’ tunnel (or bridge) from Esmonde Rd on the North Shore to Britomart, with general traffic remaining on the existing Harbour Bridge
  2. A combined passenger and vehicle tunnel (or bridge) from Esmonde Rd, with passengers connecting at Britomart and vehicles connecting to the motorway network at Wellington St or Newton
  3. The same as option 2, but with traffic connecting at Grafton.

These options are shown on the map taken from the study below:


The study found that for passenger transport alone, option 1 was the best option.  This option also had the least environmental impact.  However, for reasons that are not entirely clear, the final recommendation of the report was for a combined road / rail tunnel –  a variation of Option 2, even though this was estimated to be billions of dollars more expensive than option 1. The study does not discuss the impact of the new multi-billion dollar Western Ring Route motorway between Manukau and Albany, presumably because this route had not been finalised at the time of the study.

The report is discussed in more detail in this transportblog post.


Route Protection

In June of 2015, the New Zealand Transport Agency (NZTA) called for registrations of interest for work to complete route protection and to secure designations for the Additional Waitemata Harbour Crossing (AWHC).  The designation work focuses on advancing the NZTA’s preferred option of twin tunnels under the Waitemata Harbour, with three lanes of general traffic in each tunnel.  The artist impression also includes a cavity for rail in the “sump” of the tunnel, although the NZTA project page makes no mention of when rail might be built, if ever.


NZTA say a Business Case for the two motorway tunnels will be prepared for the project after the designation work is completed, not before.

This designation work is now underway, and it is likely that a Board of Inquiry process will be held later in 2016, leading to a designation decision in 2017.

None of this makes any sense.   Auckland’s CBD and the surrounding motorway networks will be flooded with single occupant cars. Air pollution and carbon emissions will increase. The landscape will be blighted by exhaust ventilation stacks 10 stories high.

There has to be a better way.


Rail to the North Shore


A rail crossing will have the capacity to carry more people at peak times than a six lane vehicle crossing.

It is reasonable to assume that the peak capacity of the proposed road tunnels will be the industry accepted standard of 1,800 vehicles per hour per lane. At peak times in Auckland, the average occupancy of a car is just 1.4 people. This equates to 2,520 people per hour per lane, assuming unobstructed flow at either end of the tunnels. At this stage, none of the six lanes will be for high occupancy vehicle, buses or light rail.

In Auckland, our new six car electric trains have a capacity of 750 people. A train service running every five minutes will therefore move 9,000 people in a single  hour – 1,500 more people per hour than three vehicle lanes.  With larger trains or increased frequencies, this figure will be higher.

But it isn’t just the capacity of the vehicle tunnels that will be a constraint.  The capacity of the surrounding motorway network will be strained as multiple lanes merge into the existing motorway network to the north and south. Bottlenecks will simply move and continue to occur. A flood of single occupant cars into the CBD will add to the vehicle congestion of the inner city as they look for a place park.


Carbon and Environment

Transport is responsible for about 25% of NZ’s total carbon emissions. While there is a lot of talk at the moment about electric cars and the possibility that they might reduce emissions, the most proven high capacity electric vehicle is a train.  By extending the reach of Auckland’s electric rail network, we can reduce carbon dioxide emissions and reduce our reliance on imported fossil fuels.

The project as it is currently proposed will also have considerable negative effects on Northcote over the period of its construction, which is likely to be at least five years. This transportblog post discusses the exhaust ventilation stacks that will be required at Northcote and at Fanshawe St, estimated to be ten stories high.


Cost and Economics

The 2008 Waitemata Harbour Crossing Study stated the indicative cost of a rail only crossing would be in the $1.2 – $1.5bn range.  The same study stated the cost of a combined road / rail tunnel would be in the $3.7bn – $4.7bn range – at least $3bn more expensive. Note these costs are for the tunnels alone.  Additional work to expand  motorway capacity beyond the start and end points of the tunnel is not included, and likewise the cost of building a rapid transit network on the North Shore is also not included.  However, three billion dollars could go a long way to establishing a rail network on the North Shore.

In 2011, the NZTA commissioned a Preliminary Business Case for their preferred tunnel option, compared to a bridge crossing. That study calculated a benefit cost ratio (BCR) of just 0.4.  This implies that for every dollar spent, just 4o cents of economic benefits would result.  The report is discussed further in this transportblog post. A further business case study is planned for the final design, but oddly this will be done after the designation decision has been made in 2017.

The Preliminary Business Case also contains a discussion on funding options, including tolling of the new crossing at levels of $4, $6 and $8 per crossing. The study concluded that “a toll on both crossings is required to make a material change in the cost of the project to the government”. The existing Harbour Bridge and any new tunnel would both have to be tolled as “the majority of traffic would opt for the toll free route restricting the amount of revenue available to service debt after paying for maintenance and operational costs.”


Better Alternatives

A cost benefit analysis for a rail only crossing has never been carried out, even though a number of options could be considered including heavy rail or light rail.

In 2011 the NZTA commissioned a study claiming that a North Shore rail project would be in the vicinity of eleven billion dollars.  The study authors claim that the entire network would have to be heavy rail underground.  This study has been thoroughly debunked in this transportblog post.

A more realistic alternative could look like this proposal, but as the campaign progresses we will investigate other options too.


We need your support to make rail to the North Shore happen. Sign the petition here.