Another giant document that Matt L got in an OIA request to NZTA and passed onto me is all about what’s called the “North Harbour Strategic Study”. Basically it just seems like NZTA trying to find a way to justify spending a huge chunk of money on building more motorways, but before we get onto that let’s take a look more broadly. This is the general area the study looked at:
In essence, the focus is largely on the interchanges of State Highway 1 with SH18 (Upper Harbour Highway) and the Albany Expressway/Greville Road.
A big debate on this blog over time has been the issue of whether it is politicians or the “transport experts” who are largely to blame for the auto-dependent decisions that we have been making over time, and continue to make. I know quite a few engineers get rather grumpy when bloggers on this site (and I think I’m particularly guilty of this) blame them, rather than the politicians. What I want to highlight through this post – using this North Harbour Strategic Study as an example, is how engineers and planners ‘frame’ the argument and present to the politicians something that looks like a compelling case – even when in reality approving large-scale expenditure on a project like what’s proposed in the study would actually go against most of the high level objectives Auckland’s trying to achieve.
To summarise: from time to time the corridor gets congested and because congestion in an unspeakable evil it’s necessary to widen the motorway and add more capacity. You almost know how this is going to turn out already. Though to give at least some credit where it’s due, at least the full problem definition makes some reference to public transport and to the severance effect SH18 currently has:
Somewhat strange that delays for buses using the Northern Busway after the proper busway peters out at Constellation isn’t also identified as a significant part of the problem. Though reading on a bit further, improving public transport through the study area is highlighted as a key objective for the project:
Different options for “solving” these “problems” are then put into various packages, with each package containing a number of different infrastructure interventions and often building on previous packages.
I think there’s been a slight error in the formatting of the list above. The difference between package 4 and 4a comes down to whether or not the SH1/SH17 interchange is fully grade separated, with 4a including the grade separation. Somewhat incredibly, none of the packages include a full busway upgrade along State Highway 1 between Constellation and Albany – even though this would seem to be the absolutely most necessary and no brainer transport upgrade needed in this whole area.
Unsurprisingly, package 3 is the most expensive option – as it involves a whole heap of flyovers and grade separation. Of course it also generates the greatest amount of benefits, so comes out with a cost-benefit ratio of 2.0: just on the cusp between a “medium” and “low” according to NZTA’s assessment methodology.
Packages 3 and 4a, with the main difference between the two seeming to be access to Paul Matthews Drive, are concluded to be the two preferred options to take forward into the future.
The small text is a bit tricky to read but the it seems the basic approach is a full motorway-to-motorway interchange plus west-facing on and off-ramps from a realigned Paul Matthews Road. Paul Matthews Road then ducks under SH18 to connect with the existing Constellation Drive. Also of note is mention of extending the Northern Busway as just a possible future project.
It seems the basic approach here is just to whack a couple of additional giant flyovers above the existing interchange to remove any conflicting movements from traffic heading to or from the Albany Expresway.
Reading through all the details of large projects like this, and seeing cost-benefit ratios that seem relatively good – it’s easy to find yourself seduced into thinking that this is a worthwhile project. You can see how the actual decision-makers would be going “well it does seem to fix a congestion point, it does seem reasonably good value for money…” and so forth. But really when you take a step back and think about it:
- It’s not far off half a billion dollars to build a tiny bit of additional motorway and a couple of fancy interchanges
- All those flyovers and interchanges are probably going to be massively ugly and further create severance between different parts of the study area
- The project can’t even bring itself to recommend improved bus shoulder lanes, let alone an extension to the Northern Busway that might actually reduce traffic pressure on State Highway 1
- While there is quite a lot of discussion in the report about PT connections to the west via SH18, they are highlighted as really only being suitable “some point in the future”. So the same old “yeah we’ll do PT one day but let’s build all these roads first” ideology
I’m not quite sure where this study has ended up or whether this project is still a priority for NZTA. While I can see how annoying it must be to have just that last little bit of the Western Ring Route not quite at motorway standard (once the Waterview tunnel is built), that seems a fairly small problem to require a half billion dollar solution. Plus without a decent PT component, this would be another half billion dollars further entrenching Auckland’s car dependency.