I went along to the NZTA open day on the Puhoi-Warkworth section of the “holiday highway” project today. There was a lot of information there, and it was definitely worthwhile making the trip. Most of my opposition to the Puhoi-Wellsford road of national (party) significance so far has been because I think it’s poor value for money and because I’m worried that it will delay essential safety upgrades to the existing state highway one road. But the more I find out about the exact details of the route of the Puhoi-Warkworth section (which is probably the easier section of the two), the more I worry about other aspects: like its environmental effects, like its potential for a cost-blowout, like its geological stability and so forth.
As I noted above, there was a lot of information available and I took along my camera to ensure was able to share some of that. While there was a series of posters with typical propaganda for the project (I noted with interest that the preferred alignment was left off the “landscape architecture” poster), perhaps the most useful thing was simply a giant map of the current preferred alignment – which includes indications of the earthworks required for construction.
The first section, shown below, starts at the current Johnstone’s Hill tunnels:
To explain the image above a bit, the existing route is shown in orange (you can see the state highway 1 symbol along it), the proposed motorway is shown as the three thick black lines, while the motorway footprint (I assume the land NZTA will need to acquire to construct the project) is outlined in red. The thin black lines on each side of the proposed motorway show the level of cut and/or fill – in essence the extent of earthworks that will be required. I’ve highlighted in blue the necessary viaduct bridge that would be required – it’s around 200m long to give a sense of scale to the diagram.
Shifting a bit northwards, you can see a bit more clearly in the diagram below the cut and fill that will need to be made to construct the motorway in this area. It seems to be basically running along a ridge (this is shown more clearly in the video). 
Shifting northwards even further the new motorway starts to move away from the existing road a bit more – to avoid Schedewys Hill I presume. 
Once again I’ve shown the viaduct in blue to make it stand out. I think this one is also around 200m long.
As might be obvious in the above map, the level of cut and/or fill in this area starts getting very very extensive – many hundreds of metres across in areas. The maps below zooms in a bit, and I’ve highlighted the extent of cut/fill to make it a bit clearer:
There are going to be some pretty massive earthworks to complete this section of the route in particular. With such huge cuts and fills, the landscape is also going to be pretty dramatically altered.
Shifting further north again we come to a particularly interesting part of the project – two massive viaducts pretty much one after the other:
You can also see them in the video:
From my calculations, each of the two viaducts will need to be around 500 metres long. That’s roughly equivalent to the Waiwera viaduct on the current Northern Gateway Road – which looks like this from below:
Two of them in a row. Wow, that’s going to be interesting.
Shifting further north again, we start to get into the area of thinking about Warthworth bypass options. Interestingly, as I was standing there staring at the big map there was a local next to me who was giving the NZTA official very much a piece of his mind why it was essential to just build the Warkworth bypass for now, and to build it as quickly as possible. Of course I couldn’t resist chipping in with “and look how nice and flat the land is compared to the rest of the route” and “if we solve 80% of the problem for 10% of the price, isn’t that a good thing?” Interestingly, the only response the NZTA official had to the Warkworth bypass idea was “but the worry then is we never get around to building the southern part”, to which I wanted to reply “yes, that’s the point” – but I held my tongue!
Looking at the indicative route on a simpler map shows how easily we could link in a Warkworth bypass:
So we basically do build the first section of the road, do a quick link in along Perry Road, with a new roundabout on State Highway 1 and we have a Warkworth bypass. Looking a bit closer, it does feel fairly simple (existing Perry Road is in red, new link route in yellow):
The link through is most definitely feasible I would think – though obviously Perry Road would need to be widened and upgraded.
There were plenty of other interesting things I found out through discussions with the various officials there. It would seem that the geological conditions between Warkworth and Wellsford are incredibly challenging, and it may be another year before NZTA can release something similar to this for that section. Furthermore, it would seem that NZTA don’t have much of an idea about whether or not to put in the Puhoi interchange, but they did note building it might be pretty environmentally destructive – and I see their point on that note.
All up, it became obvious to me that focusing on the Warkworth bypass for now is a completely no-brainer. The southern part of this project (between Perry Road and Puhoi) is exceptionally challenging, in terms of the earthworks and viaducts required to achieve a motorway standard road. The environmental effects of the project’s southern part are also pretty massive: in terms of earthworks, landscape modification, visual effects and vegetation clearance. I suspect that NZTA are going to struggle to construct this without blowing most of their budget for the whole Puhoi-Wellsford project: which will leave very little for the even more challenging section to the north.
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As an engineer, it looks like a great project! But yeah the Warkworth bypass looks like the only bit worth doing. I wonder if you netted out the benefits and costs for the Warkworth bypass, how bad the BCR would be for the rest of the route.
Do you know who the engineering consultants are for the work?
SKM are doing all the engineering and design work.
I really think you need to write this up for the Herald as a comment Josh. Just do the low hanging, high-benefit bypass. 900 words,
Engineers’ wet dreams? It looks as if they’ve given themselves the opportunity of doing everything that the majority of engineers like doing: playing with very big toys; stuffing up the environment in all possible ways; and paying themselves vast consultancy fees while doing it. And because a provincial National party minister, dreaming of the day when he can drive his big car from his Silverdale McMansion to his Omaha bach in half an hour or something, wants a parliamentary seat, they don’t really have to justify it to anyone else. And so much more fun than just recommending the instant demolition of an old hotel because it will last all that much longer. How very deeply depressing.
Doing the bypass only would mean the major accident cost savings from the southern part are missed, and this cost saving is probably larger than the time and vehicle operating cost savings?
The most dangerous section is through Dome Valley, which it seems is being put off further and further.
I think that a Schedewys Hill bypass is probably necessary if you were going to keep the existing road for an extended period of time. I think that’s the most dangerous section between Puhoi and Warkworth.
The Schedewys Hill bypass has been investigated by NZTA, and was costed at $64 million. See
http://www.parliament.nz/en-NZ/PB/Business/QWA/6/4/1/QWA_10165_2010-10165-2010-David-Shearer-to-the-Minister-of-Transport.htm
and note the PDF table downloadable on the right hand side.
Concur, and for once to everyone. In my Transit days there is no way that a project like this would have seen the light of day. The Warkworth bypass is another matter, of course.
Two other things:
* this project looks like being the Auckland equivalent of Transmission Gully, which has many of the same engineering and economic issues.
* the country which the railway goes through, to the west, is every bit as challenging, and would face almost as many issues if anyone tried to upgrade it.
Rod Oram very good on this in today Sunday Star Times: http://www.stuff.co.nz/sunday-star-times/business/4366408/Going-down-the-wrong-road
I read somewhere recently that this section alone would cost about $900 million leaving only about $600 million to do the remaining distance which is longer and has more trick terrain. seems to me certain that this will blow the budget yet if a PT project came in by even $1 over budget it would get a grilling from the minister. In fact I remember reading that there was something like $20-50 worth of other improvements that could be done to the Auckland rail network at the same time as electrification, while they weren’t essential they would have greatly added to the capacity and flexibility of the network but they had to be cut because the minister/government didn’t want anything else spent on rail.
i live in wyllie road in warkworth it takes me 30 – 40 minits to get to auckland so why do we need this road we dont and people in warkworth dont so take your road and put it up your ass
Admin – thanks for posting these pics. Interesting that the NZTA hasn’t published these diagrams (the ones that you have taken pictures of above) on their website.
You get the feeling Warkworth-Wellsford will never get built. Maybe they could levy the property developers of north Warkworth who stand to make a fortune.
“Engineers’ wet dreams? It looks as if they’ve given themselves the opportunity of doing everything that the majority of engineers like doing: playing with very big toys; stuffing up the environment in all possible ways; and paying themselves vast consultancy fees while doing it. And because a provincial National party minister, dreaming of the day when he can drive his big car from his Silverdale McMansion to his Omaha bach in half an hour or something, wants a parliamentary seat, they don’t really have to justify it to anyone else. And so much more fun than just recommending the instant demolition of an old hotel because it will last all that much longer. How very deeply depressing.”
Engineer-bash much? Yes, some of us (myself included) love big projects. But that doesn’t mean we support this (I’d much rather build large railway tunnels and bridges and cycleways that don’t leave you stranded when they need to cross arterials). Also, you make it sound as if the engineers/NZTA “sold” this to Steven Joyce. In fact HE pushed them to do it. HE is crowing that all this is from a standing start, and that the motorway had not been considered in the past. Blame where blame is due, mate.
Matt L – in 2009, the motorways funding ran 150 MILLION over budget. In 2010, it ran 100 million over budget. So not only does Mr Joyce fund them with massive increases in the NLTPs, he then allows them to exceed that ridiculous budget at sizes unheard of…
That Perry Rd bypass is not going through some very fine vineyards is it? There are some excellent Bordeaux reds coming out of that region. Has the impact of the loss of vineyards been factored in?
Whilst the southern part of this horror is fraught with engineering problems the northern part where it winds through the west of Warkworth and then down through a pristine valley to join SH1 is literally going to be built on the misery of innocent people whose only sin is that they tried to build something nice in the country. Many people are having their homes taken off them, still others are being forced to accept risk in this hare-brained scheme by having this road rampaging through the countryside within a few hundred metres of their homes. Where land is required the RTA can, under the Public Works Act (PWA) pay the unfortunate ones market value for their properties. All those “close neighbours (quaint phrase that) of the motorway, whose lifetsyles will be forever compromised and whose property values are diminished at least until well after this road is built and the engineers have finished faffing about, get nothing – except perhaps a form of house arrest for the next 7-10 years!
The process which the PWA mandates allows the wishes of the many to ride roughshod over the rights of the few – with no compensation given to the unfortunate few. So – all those who think that this road is a wonderful complement to the Warkworth area – would you please put your hands in your pockets and pay what is only morally right – compensation to those who are unfortunate enough to be in the way of this engineer’s “wet dream”.