ACT’s candidate for the Northcote byelection, Stephen Berry, may not have won but caused quite a bit of discussion with his rather crazy motorway plan that we first discussed a few weeks ago. It would have cut a gigantic swathe through the green spaces of the electorate that he supposedly wanted to represent. Simon Wilson also covers the proposal in quite a bit of detail here.
In terms of its likely cost, environmental and social impact, the project is obviously a non-starter. Putting those issues aside though, it probably would be reasonably effective in drawing traffic away from State Highway 1. Assuming it was also somehow linked into State Highway 20, it would also ease some pressure on spaghetti junction, although SH16 from Pt Chevalier into town might become unbearably congested. So, billions of dollars and a path of destruction across the North Shore and inner west, but at least it would “make a difference”.
This got me thinking once again about NZTA’s actual current proposal for an additional roading link across the Waitemata Harbour. We have discussed this project many times over the past few years, with the general flavour of those posts being along the lines of this being the stupidest project ever. The map below shows what’s proposed:
In a nutshell, through-traffic (i.e. vehicles not travelling to Shelly Beach Road or the city) would use the new tunnel and the existing harbour bridge would effectively become a huge off-ramp. The two motorways would merge by Esmonde Road in the north.
While the impact of this proposal (especially if it’s a tunnel) would obviously be nowhere near the scale of Stephen Berry’s proposal, the effects are still massive. Just look at all that required reclamation around the Onewa Road interchange (all maps from here):
And check out the maze of cut and cover tunnels underneath Victoria Park. Almost certainly that’s going to impact on the amazing trees that go around the edge of that awesome inner-city park:
Even without the separate rail tunnel, we are looking at a project that in 2010 was estimated to cost around $5.3 billion (the rail tunnels were estimated at a comparatively cheap $1.6 billion). Just as an aside, I’m pretty sure in 2010 City Rail Link’s cost was projected to be less than $2 billion, so I’d hate to think what an updated cost estimate for the harbour crossing project might be. The cost also doesn’t include any widening of SH1 north of Esmonde Rd. That is likely to be needed as far as at least Constellation Dr and could add up to an extra billion dollars.
So NZTA’s plans are for something that will be enormously destructive and hugely expensive. But, amazingly, that’s not the worst of it. The actual worst things about this project are:
- The huge increase in traffic on local streets from the project, especially those linking with the on and off ramps and in the city centre, where we are trying to reduce traffic numbers to create a more liveable city.
- The fact that the project actually doesn’t even help reduce congestion.
Starting first with the traffic on local streets, even NZTA’s own specialist report makes a fairly brutal conclusion:
Some of the increases in local road traffic volumes are pretty massive. Just look at what it does to Cook Street, for example:
The alternative to flooding the city with even more cars would be to reduce the number of lanes on the harbour bridge, such as using the space for bus lanes. So essentially spending billions for a couple of bus lanes when we could use that same money to create a crossing and an entire rapid transit network for the North Shore.
Turning next to what impact the project actually has on congestion, the results of modelling undertaken as part of ATAP in 2016 were pretty dismal. The multi-billion dollar hugely destructive new motorway link actually ended up being just as congested as the Harbour Bridge would be without the project, while the central motorway junction ended up much more congested! Therefore the only real beneficiaries would be those driving between the North Shore and the City Centre – hardly the trips we would want to encourage to move from PT to car!
So let’s summarise this. NZTA’s official project:
- Creates huge environmental destruction through massive reclamation around Northcote Point and would essentially destroy part of Victoria Park, at least during construction.
- Undermines everything Auckland is trying to achieve in its city centre by encouraging more car trips into this constrained space.
- Was estimated to cost $5.3 billion in 2010, noting that other large projects have nearly doubled in cost since 2010.
- Doesn’t actually reduce congestion for those travelling past the city centre.
There’s one bit of salt for the wound. The 2010 version of the crossing showed rail tunnels separate from the motorway ones, the latest thinking is to combine them, as shown in the second diagram. The problem though, as I understand it, is no consideration has been given as to how the rail lines in those tunnels would then connect to the city or if that connection ties in with how Auckland’s rapid transit network is evolving. So while the NZTA will claim the benefit of including a rail crossing in their evaluations, it’s not necessarily a rail crossing we may be able to take advantage of, at least not easily.
Stephen Berry’s harbour crossing idea may be crazy. But NZTA’s official one, that they have spent well over a decade and many millions of dollars working on, isn’t much better at all.