Talk about an additional harbour crossing has existed for decades. With this post I thought I’d look at some of the many proposals that have existed over the years.
Presumably the first discussions about building a new crossing happened shortly after the existing bridge opened in 1959. I also assume those first discussions ultimately became the clip-ons that were completed in 1969. Following their completion traffic volumes quickly increased and there was certainly discussion about another crossing in the mid-70s. In a series of op-eds in the Herald during 1975, Mayor Sir Dove-Myer Robinson said that a decision on a new bridge or tunnel was urgent, claiming the bridge would reach “maximum carrying capacity” by 1981/82.
Of note, at the time of his writing, the bridge was carrying about 65k vehicles per day, nearly double what it was before the clip-ons opened 6 years earlier. Likely impacted by the oil crises of the 70’s, growth slowed and by 1982 the bridge was carrying 80k per day. Had that growth continued at the same rate as prior to 1975, a 1982 estimate would be more like 100k. Either way, these clearly weren’t maximum capacities as the bridge currently carries about 171k vehicles per day.
I’m not sure if there were any formal investigations to new crossing routes but the first one I have found any records of is from 1988.
The study was for the Auckland Regional Authority and done by the Maunsell (now subsidary of AECOM), Parsons Brinckerhoff and the Ministry of Works and Development. Unfortunately I’ve only got the PT route options but they give a good idea of the thinking at the time. The notes suggest the crossing would have been used by either light rail or a guided busway like Adelaide’s O-Bahn.
There were two route options each for either a bridge or a tunnel. The tunnel would have been an immersed tube, instead of a deep bored tunnel (like Waterview). One option would be just east of the existing bridge and connect to the city through Wynyard, much like current plans, and the other would have cut through the tip of Bayswater and Stanley Point. The tunnel options seem to involve some amount of reclamation for ventilation and presumably to surface the vehicles.
For the bridge option there are also some drawings of what it may have looked like.
1997 saw a significant study undertaken for the Auckland Regional Council by Opus.
One thing it notes in its summary is
Traffic forecasts for roading options indicate that the additional cross harbour capacity provided by a four lane crossing is likely to be fully utilized not long after the year 2021.
The study looked at 14 different corridors comprising of 48 options bridge and tunnel options before narrowing down to a shortlist. Some of these were real doozies and would have had monstrous impacts on the city centre. Many were also aligned to connect to the now defunct Eastern Corridor.
All Bridge Options
All Tunnel Options
After further assessment, a shortlist of options was created. These are shown below with tunnels as dashed lines
A summary of the assessment of those options is below. As a guide to the listed cost, The RBNZ’s inflation calculator says that $100 million in 1997 is worth about $153 million now. That would put even the most expensive of the options, a tunnel from Esmonde Rd to Judges Bay, at about $2.6 billion.
You may notice mention of two public transport options which would hook into the future Northern Busway.
Like with the 1988 report, there are a few drawings of what some of the options would look like. The most notable are:
Option 3.1 carving across Devonport, having already crossed Bayswater.
Option 15 which would have put a motorway down Wynyard Point, the western side of Wynyard Quarter and a new viaduct through Victoria Park
What is not shown in this image but you can see on the map above is that route 15 also includes this above-ground route straight though Auckland Grammar.
In 1998 the options went out for public consultation and following the feedback it was decided the next crossing “would be situated in the vicinity of the present harbour bridge“. Also that whether a bridge or tunnel across the harbour, the crossing would connect directly to the Northwestern Motorway via a tunnel through Ponsonby.
Following the study above, in 2003 Transit NZ (predecessor to the NZTA) undertook another study confirm the options that would be meet the outcomes decided from the 1997/98 study. You can see the document on the wayback machine but unfortunately the graphics are low quality.
A preferred option for a bridge and tunnel scheme where selected. No definite cost was given for the options but it does note that any option would likely cost more than $3 billion ($4.3 in 2019).
The preferred tunnel would have been an immersed tube following the dotted line and connecting to the CMJ. It would not have had the tunnel connection to the Northwestern as would use the above ground connections that have since been built.
The preferred bridge option would see the motorway cut under Northcote Point leading to a bridge 500m west of the existing bridge before connecting back around Pt Erin where the route would dive into a bored tunnel under Ponsonby. An artists impression of the bridge of which is below.
For those interested, the document includes some smaller images of the bridge options for either side of the existing bridge showing some very utilitarian structures.
With the planned redevelopment of Wynyard Quarter it was decided another study was needed to reassess crossing options. This study was primarily undertaken by SKM (since acquired by Jacobs).
Like with the 1997 study, they started with a long list of potential options. This time the number of them had expanded to 159 and included heavy rail linking into Britomart. The image below is a more recent high-level graphical representation of those options – bridges and tunnels on the same alignment were considered separate options.
This was then whittled down to a shortlist of three alignments,each of which had a few variations within them.
This was further refined and Option 2C, using bored tunnels, became the recommended option. A feature of this, that continues in the proposals to this day is that the Harbour Bridge would effectively become one big off-ramp to the western side of the city with the new crossing only being for traffic bypassing the city or heading down Grafton Gully.
The 2008 study lead into a more detailed business case by PWC and various other assessments that took place in 2010. That work estimated a road bridge would cost about $3.9 billion with a Benefit Cost Ratio of 0.6, a road tunnel about $5.9 billion with a BCR of 0.4 and a rail tunnel $1.6 billion (no BCR stated). Given what we’ve seen happen to the costs of other projects since then, most notably the City Rail Link, those costs are likely a lot higher now.
Some of the drawings of the bridge versions of that are below.
Since 2010 work on another crossing has focused on protecting the route but there has been little information in public on just what this entails. We do know that another look at alternative routes, likely similar to what happened in 2008, occurred in 2016 and 2017 as part of the route protection assessments. It was also decided during the Auckland Plan process that a tunnel would be the preferred solution. This has often felt as if it’s more about no one wanting to make a decision on a structure that would so dramatically change the skyline than anything else.
Another change in recent years has been a focus on combining the road and rail tunnels into a single crossing instead of having them separate. At first I think this was more about finding ways to get a quicker and cheaper rail crossing built as the original plan was to repeat the mistakes of the past and build a new road crossing but leave any rail crossing for a separate project.
But the most recent information released by the NZTA suggests some thinking on the makeup and timing of projects may have flipped. A PT crossing is now accepted as being needed sooner than a road crossing but the highway engineers seem to want to keep the tunnels combined as it likely now the only chance they’ll now get to also get a road crossing. That information came from some new modelling showing that building a road crossing was a waste of money as it undermines Aucklands strategies and actually makes congestion worse. It suggested the best outcome came from building a light rail only crossing.
2009 – ANZAC Bridge concept
In 2009 a group of private companies suggested a new bridge to be built by 2015 to commemorate the ANZAC centenary. It would follow a similar alignment to option 2C from 2008. What was interesting about this proposal is they planned it to replace the existing bridge rather than add it as an additional crossing. They would pay for at least part of it through redeveloping the land used by the motorway through St Mary’s Bay and along the eastern edge of Northcote Point south of Onewa Rd – an idea that seemed improbable.
What have we learnt
Unsurprisingly the general route concepts that came up 30 years ago are the same ones that come up today, albeit with minor tweaks. This is not surprising given Auckland’s geography hasn’t changed during that time.
One thing that is clear though is discussion about a new crossing has been a great make-work scheme for consultants with major repeats of the same work coming out every decade or so. Since 2013 alone the NZTA has spent about $25 million on investigating another crossing and $55 million on property purchases. I wonder how many more millions have been racked up over the previous decades investigating the idea.
What’s also clear is that predictions about the existing bridge running out of capacity or there being an issue with the clip-ons, thus requiring a new crossing are often woefully inaccurate. Related to this, perhaps the single biggest thing that has reduced the need for another crossing has been the advent of the Northern Busway which has meant a lot more people can cross the bridge at peak times.
I think we’ll hear calls for a new road crossing continue to pop up over the coming decades and we’ll probably see these evaluation processes continue to occur.