The announcement of the Puhoi-Wellsford motorway on Wednesday detailed the cost of that road to be $1.4 billion. Here’s the relevant part of the press release:

…$1.4 billion strategic upgrade of State Highway 1 from Puhoi to Wellsford…

It would seem to me that this is the cost of the whole Puhoi-Wellsford stretch, and not just the Puhoi-Warkworth first stage. It seems as though the second stage is the more complex (or at least that’s what NZTA are saying), so perhaps it might be realistic to expect the Warkworth-Wellsford bit to be the more costly, particularly as it’s a bit longer that the Puhoi-Warkworth stretch. So let’s just say perhaps an $600 million/$800 million split for the two projects. Now how realistic is that kind of budget? Let’s have a look at the southern portion first, where I have matched up the route diagram in NZTA’s information booklet with Google Earth, to show where the proposed route alignment will go – and the rather large hills that it seems to encounter on the way: Two areas that would seem to be particularly problematic are labelled as “steep slopes”. There’s a rather tricky hairpin corner for the southern one, while for the northern one the current alignment is pretty straight but quite steep (I can’t understand why NZTA would want to shift from that current alignment there actually.)

Now while I am sure that nothing here is impossible, there would be quite significant earthworks required and perhaps even some expensive bridging or tunnelling.  Keeping in mind that the Orewa-Puhoi motorway was only 6km long and yet cost $360 million to construct, it may be a tad optimistic to suggest that a 15km motorway could be constructed to a similar standard (and across what appears to be similarly challenging terrain) for not even double the cost.

The Warkworth to Wellsford stage is even trickier, as you can see in the diagram below. The current road winds its way through the “Dome Valley”, which is very hilly terrain and is well forested. I would suspect that some serious tunnelling (or alternatively some pretty horrendous earthworks) will be necessary to bring this section of road to fruition. Which means that $800 million might really be pushing it for this stretch of road. I guess ultimately it comes down to comparing the “per-kilometre” cost of this new road against the Orewa-Puhoi one, which we know cost $360 million for around 6km – so $60 million per kilometre. Of course that included a tunnel, which might have bumped things up a bit, but I think it’s unlikely we would get away with building this 38km road through mountainous terrain without any tunnel. 38 km by $60 million per kilometre comes to a total of nearly $2.3 billion – quite a bit more than the estimated $1.4 billion that NZTA have come up with here.

That’s a pretty expensive upgrade for something that is only used by around 15,000 vehicles a day. A basic Warkworth bypass would be only 5km long, and across pretty flat land. That might cost around $100-150 million, and I suspect would achieve many of the same benefits that this super-expensive holiday highway is meant to provide. Surely that’s a more sensible option?

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  1. I have to say i thought the idea of a motorway/highway all the way to Warkworth was a waste of time and money.
    I agree about bi-passing Warkworth and Welsford and may be straightening out some of the bends from Puhoi but as you rightly pointed out recently, the only problem is mainly in holiday times and i assume Friday nights in summer.
    The media raves on about Steven Joyce’s abilities but for the life of me he does nothing to inspire confidence in me.
    Joyce’s head in the sand attitude to public transport, his deceit and down right lies about Waterview costings lead me to wonder how competent he really is. Time will tell but i will reserve my judgement about how competent he is with the transport portfolio.

  2. The benefit of a two stage project, especially in this case is that stage 1 coulkd get built without stage 2, so stage 2 may never get built. I imagine stage 1 will have a much higher BCR than stage 2.

    I still think this project isn’t the best use of money, ut the Warkworth bypass bit could be worth doing (no challenging terrain, as it caters purely for intercity traffic little induced demand). Maybe we should try and turn it to a 3 stage project, with Warkworth bypass being stage 1, and hopefully the other 2 stages see the money transferred to public transport.

  3. My thioughts entirely Nicholas. Build the Warkworth bypass and then see where things are at. Maybe a Wellsford bypass might be needed in the longer term, as SH1 goes right through the centre of town, although we are seeing some ‘defacto bypasses’ emerging, like the Wayby Valley Rd link to Mangawhai Heads.

  4. Absolutely. There is no need for the gold plated solution – there are other investments in transport that are desperately needed.

    I hope that Labour continue to give them hell over this. It’s going to be a while.

  5. George, from memory Joyce’s press release said that he was considering building the Warworth bypass first – but that thought had to go into how it should link up with the existing road. It seems as though David Shearer is pretty determined to nail Joyce over this project. Hopefully the project’s stupidity will eventually become clear to the general public.

  6. Labour have been doing a pretty poor job at nailing National for any of their transit plans – perhaps due to lack of traction in the media, but why is it that I don’t even know who Labour’s transport minister is? Is s/he as incompetent as Joyce or is s/he just as much of a road addict as Joyce so has nothing negative to say?

  7. “but why is it that I don’t even know who Labour’s transport minister is?” It is Darren Hughes (that is transport spokesperson now they are in opposition). And while he has got some visibility as Chief Whip he has been almost invisible on transport issues.

    “Is s/he as incompetent as Joyce or is s/he just as much of a road addict as Joyce so has nothing negative to say?” Dissapointingly one of the few issues where Hughes has been visible is in lobbying for Transmission Gully, a road close to his former electorate of Otaki.

  8. Hughes has been a bit overloaded with being Shadow Leader of the House, Chief Opposition Whip and Trasport Spokesperson. I think he has basically delegated Auckland transport stuff to David Shearer, who I think will be more visible this year.

  9. If there had been a little more forward thinking, SH16 should really have been the candidate for upgrading, rather than the Northern Motorway. Putting a 4 lane motorway generally along the current SH16 alignment from Westgate through to Wellsford would have far cheaper as it would mostly traverse flat(tish) farmland, rather than the hilly bush clad hills nearer the East Coast.

    It would have been a smarter option as well, as this would have created a true western bypass, and would have got an immense amount of Northland through traffic (especially trucks) off the AHB.

    The Northern Motorway could have ended at Albany, and we wouldn’t have had to build ALPURT at all, especially the expensive B2 section, let alone contemplate a motorway northwards from there. Indeed the AHB and Northern Motorway wouldn’t probably even be SH1 under this scenario, as SH1 could be re-routed around either the Northwestern motorway or eventually the WRR beginning at Manukau.

  10. Yes even though we are a motorway mad country we don’t even really do them well, by-passing inter-regional traffic away from CBDs is pretty standard practice…

  11. Do many people use Kahikitea Flat road and then SH16 to avoid the holiday traffic? Maybe Kahikitea Flat road should be turned into a state highway, then it can be given small upgrades and advertised as an alternate route. Yet another great way to save a billion dollars.

  12. I think some people do Luke, although generally it’s the road from near Silverdale that links with SH16 that’s used to avoid the worst of the congestion.

    The ironic thing is that with NZTA focusing their attention on this 38km white elephant, we’re actually seeing progress on Warkworth bypass – which is all that’s really needed – being delayed, because NZTA’s too busy wasting their time on $2 billion motorways.

    Maybe that’s the best angle to attack this holiday highway from, that Joyce is actually delaying the small project because he’s too focused on something huge and unnecessary. Like he’s delaying solving a problem that merely needs a small hammer, by taking 9 years to build a giant massive fucking slegehammer.

  13. We didn’t lose the opportunity 50 years ago, (though I agree if it had been done back then it would have been a lot easier and better for Auckland as a whole). It was more in the 1990’s, when ALPURT was approved. Up until that time the Northern Motorway went to Albany, which would have been a logical end point near the MUL. SH1 northwards from that point would have been a regional road serving Silverdale and Orewa.

    Once we started extending the Northern motorway massively northwards by building ALPURT, especially the B2 section, we basically forced any future road connection upgrades to Northland to be via the Eastern corridor (at or near the current SH1) as we now have already spent so much on this route it is not worth starting again somewhere else. The problem with this corridor is eventually you hit the difficult hilly sections from Orewa north that are very expensive and environmentally problematic to push a 100km/h design speed 4 lane median divided road through.

    If, back in the 90’s, a decision was made to upgrade SH16 and the same amount of money was spent as has been so far to build ALPURT, SH16 would be a motorway well north of Helensville by now. It also could have been built initially as a cheaper two lane grade separated limited access expressway, which could have been upgraded as needed (and I don’t believe it would have been needed for many years as a lot of traffic would have still elected to use SH1).

    This would have given way better route security as well (you could easily get a big landslip, or some other problem such as an Aramoana style armed offenders incident in the vicinity of Puhoi which could shut down both the existing SH1 and the new motorway if there are located close to each other).

  14. I must say I have always found the SH16 alternative route quite windy, although I understand there are some projects underway (or at least planned) to straighten some of the nastier bits.

  15. Extended motorways are fun, going all the way north. At least, they can be within the realms of imagination.
    However there is a difference between when you can apply that imagination to reality, and when you are just dreaming.
    Travelling between Auckland and Dargaville (where I live) only becomes problematic during peak holiday traffic times, which surprising, happen in the holidays, and the other congested areas (being Warkworth and Wellsford) are typically the only real all-year congested areas.
    Realistically, a bypass of these two towns is all that is needed.
    Then perhaps they could consider promoting rail travel. I seriously would opt for taking a train places, rather than taking my car. On one set of rails – how many times does a train get held up in congestion?

    Anyway. If they are so hell-bent on building a Northland Motorway, wouldn’t it be most cost-effective to just build a road that travels by, or at least (in cases like Dome Valley, or wherever else they have challenging terrain) near the current one?
    The Waikato Expressway is like that, isn’t it?
    After all, it’s not like you’ll need to cross over onto a lane heading the opposite direction if you already have two lanes..
    And hypothetically, what if they wanted to extend the thing further north, towards Whangarei? There is absolutely no way you can build something like that through the Brynderwyns.
    Currently traffic flow there isn’t a problem, and I can’t imagine it would become a problem anytime soon.

    I say build the bypasses first. Then, if a motorway or expressway MUST be built, then they can incorporate those bypass roads into their design.

    And that Joyce guy I’ve seen on the news a few times (I don’t really pay attention much, it’s dad that watches the news) and he creeps me out anyways.

    Shouldn’t we focus on shifting the population’s mentality to transports, such as trains?
    I’m pretty sure they don’t cost as much, and don’t take up as much room.
    And who wouldn’t want to enjoy the country, as you ride on by?
    When you’re driving, you can’t really do that..

  16. Rail costs are comparative to motorways, more so in fact but the capacity is unrivalled (up to 10 times roads), that is why the rest of the first world that is serious about their economies are investing heavily in it…

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