The NZTA has announced its preferred route to build a motorway from Puhoi to Warkworth which is part of the Puhoi to Wellsford Road of National significance. The route makes a few changes to what was announced about a year ago and said to be due to them having refined the engineering and environmental issues along feedback from locals from consultation. Hidden in the information is news that they plan to start building the motorway in 2014 with a completion date for this section of 2019. Reading through the announcement and various bits of information it raised a lot of questions but first, here is the new alignment aldong with the key changes:

We have already seen that the previous alignment would require some absolutely massive earth works along with multiple viaducts and I don’t think that this has changed much. The first question I have comes from the yellow box at the bottom of the image where they quote that Auckland, Hamilton and Tauranga generate 36% of the countries GDP. The problem with that is Auckland alone currently generates 37% of the countries GDP so getting basic facts like that wrong is not a good start. Here is the key part of the media release:

As the main road link for the freight industry, the new route will better connect Northland to the markets of Auckland and the central North Island to stimulate economic growth in Northland and the Upper North Island.

NZTA State Highways Manager for Auckland and Northland, Tommy Parker, says the agency’s traffic modelling shows that the average number of vehicles travelling between Puhoi and Warkworth each day is expected to increase from an average of 19,700 in 2012 to Puhoi and Warkworth to 31,300 per day in 2026.

“Drivers will make significant time savings on an Auckland-Whangarei journey in 2026 when the Puhoi to Warkworth section of the RoNS is operating, and these time savings are expected to be greater for heavy vehicles carrying freight.

“A divided motorway with a central median barrier will also greatly improve safety, eliminating the kind of head-on collisions which have claimed four lives on this stretch of highway since 2006.”

It seems that with this project you really need to read between the lines because what they aren’t saying is often just as important as what they do say. They claim that 31k vehicles will use the route by 2026 but the key thing here is that it is across both routes, not just the motorway. I also wonder if that increase in vehicles is based on the same growth projections used in other projects and still get used despite traffic volumes being static or even reducing over the last 7 years.

They claim that there will be significant time savings for vehicles but the key thing here is that the benefit is only for drivers coming from further north, that is because the only connection to Warkworth will be on the northern side of town. That time saving benefit was estimated in the past to only be about 5 minutes and those that live in the town will have to drive North to get to the motorway before heading South again which means for many that there will be little to no time saving benefits over what they have now.

There are quite a few other things that could have a big impact on this road.  The NZTA have said that they haven’t made a decision yet on whether it should be tolled. Their experience with the existing motorway from Orewa to Puhoi  is that even though that piece of road has greater time savings than this new section is expected to deliver, about 30% of traffic still uses the old free route. Using that ratio as an example it would mean that we would still see about 10,000 vehicles per day using the existing route and the motorway would carry about the same amount of traffic as the existing road does today. I believe that would mean it is carrying less traffic than any other motorway in Auckland and less than most arterials.

They have also said that at this stage they won’t be building an interchange at Puhoi which would have interesting outcomes.

  • The residents on Puhoi and Mahurangi West would no longer have direct access to the motorway. They would instead be forced to use the free road which takes longer and is more dangerous.  I wonder if that has been taken into account in the BCR.
  • As there is a big impact on vehicle numbers if the road is tolled, no interchange at Puhoi means that the NZTA either have to toll the whole motorway from Orewa to Warkworth or remove the existing toll. If they take the latter option they should include the remaining debt that the toll is currently paying into account as that would still need to be paid and so it should be added to the costs for the project.
  • The NZTA is going to get this consented via a board of inquiry like they did with Waterview, and you can be sure that the locals of Puhoi and Mahurangi West will want ramps built. Given the mitigation that was required for that Waterview with things like vent stack locations, I suspect the locals will have a good chance of winning but that raises another question. Part of me thinks that the reason for not including ramps at that location is that the NZTA know their time savings estimates are bogus so are going to try and force as many people as possible to use the motorway as that would make the old route much longer once again.

So what about the financial and economic aspects of the project, this is what the NZTA has to say:

  • Estimated costs for the Puhoi-Wellsford project are $760m for Puhoi-Warkworth and in the order of $1b for the Warkworth-Wellsford section
  • The Puhoi-Warkworth section has a BCR of 1.5 and the overall Puhoi-Wellsford project has a BCR of 1.0

From memory $760m is a little cheaper than when the route was announced last year but still bloody expensive for how many people will use it daily. The total cost of the project has increased though from $1.65b to 1.76B. The more interesting thing is the Benefit Cost Ratio (BCR), it isn’t clear if this includes things like wider economic benefits or what discount rates have been used, one thing we can be sure of is that they will be the best case scenario. Taking these numbers at face value they suggest the section to Warkworth is marginally ok but that the section from Warkworth to Wellsford has a BCR of only 0.6. This once again highlights one of the biggest problems with the RoNS, to get some of the bad and uneconomic parts built, they are lumping them in with other projects to bring their scores up. The NZTA hasn’t actually released that much information so I think an OIA request will probably be in order to get a copy of the latest business case.

Other than the costs, there also has been no new information the section from Warkworth to Wellsford. The indications are that they still can’t find a workable route through what is one of the most geologically unstable regions in the country. Perhaps the people working on it also know how stupid the project is and are trying to delay it as much as possible because if spending $760m on a road that currently carries only ~20,000 vehicles per day is bad, spending $1b on a road that carries less than 9,000 vehicles per day is just madness.

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  1. What’s particularly interesting is that in the NZ Herald article today Tommy Parker says most of the benefits come from bypassing Schedewys Hill and Warkworth. So why not just do that?

  2. The frustrating thing about the board of inquiry process is that they go with NZTA’s assertions about the economic benefits of the project. The only way to challenge that would be to fund an alternative analysis of economic benefits and present that to the BOI. In the Waterview case Prof Tim Hazeldine challenged the economics, but very little of what he was saying was accepted by the board.

    CBT put it to the Waterview BOI that there should at least be some kind of post implementation review of the economic case, but this was not accepted as a something the BOI should consider.

  3. Is that 19,700 figure meaning 10,000 vehicles travel all the way between Puhoi and Wellsford, and vice versa each day? What are the peak flows? Or does this figure include vehicles traveling for short sections of it? My bullshit detector is running high at the moment for this entire project.

  4. The Herald quoting Mrs Noom doesn’t help my blood pressure:

    Despite the upheaval, Mrs Noom said she believed a new motorway would be important for the development of Northland.

    “They call it the holiday highway, but it definitely isn’t,” she said.

    As a former Kerikeri resident, she was acutely aware of a need for a better road than the existing two-lane route to get goods to market.

    Mrs Noon said Northland needed to be “opened up”.

    “It’s a beautiful place north of Wellsford and they could do lots of things, but not if everything has to come through this narrow neck around here.”

    Who the fuck cares if oranges take ten minutes longer to get to the supermarket from Kerikeri? NZTA have already identified that this project won’t significantly boost Northland’s economy. And Waterview is supposed to enable SH16 as the alternative route north to Wellsford.

    1. So this project will ‘open Northland up’, via the ingenious step of not extending into Northland.

      Next up: boosting the Wairarapa economy by extending the Waikato expressway a bit closer to Hamilton.

  5. Must be an awful lot of goods being transported up there. The Herald has asked a citizen, Mrs Noon, for her opinion and then used it as though she’s an authority on economic benefit. They might’ve all have asked me!

    They just seem to build whatever they want and get back-up agreement from New Zealand’s leagues of yes men and women. There are too many sheep who don’t want to have a disagreeing opinion.

    Ben Bernanke said last year of the Fed Reserve board that if there are two people on the board with the same opinion then one of them is redundant. Why can’t boards like the BOI be like that?

  6. Any idea how much NZTA has already spent on this project? It must be starting to climb with all the consultation, geological investigation, modelling etc.

  7. One line the government keeps trotting out is that more people use the existing road per day than the rail network, it isn’t actually true but that doesn’t stop them using it. Even at a high occupancy rate that would mean about 45000 people using the road daily. By comparison by 2026 even without the CRL the rail network is projected to carry over 60,000 per day and if the CRL was opened in 2021 then the network is expected to be carrying over 80,000 per day by the same timeframe (by 2041 the rail network is expected to be carrying 130,000 per day with the CRL)

  8. All this at the same time that the govt is trotting out the ‘slash spending’ and ‘reduce the deficit’ headlines.

    Fix Schedways Hill, bypass Warkworth, straighten out Dome Valley and bypass Wellsford. All that is required really. 2 lanes all the way is not needed now or probably ever.

  9. If the strategy is to force everyone to pay $10-15 or go through Waiwera- there are going to be a lot of unhappy people up North.

  10. Whoa! Golden triangle!?

    Question: What were the timesavings from recent tunnel and bypass of Orewa? Have they had any impact on Northland’s economy? I guess it is too early to tell.

    1. The new tunnel and bypass of Orewa is better for travelling to Auckland from the North, and saves about 10 minutes. One of the benefits of that is that Orewa has redeveloped what used to be the main highway and is now quite an attractive little town.

      I agree with the points already made – bypass Warkworth and Wellsford, do something about the Dome Valley, and you’re done.

  11. At a discount rate of 7 per cent over 20 years (a common standard, I believe), an upfront capital cost is equivalent to a daily cost about 1/4000 of the total. So the section that costs $1 billion to serve 9,000 vehicles per day is equivalent to a cost of about $27 per vehicle trip.

    So the economic benefits have to be at least $27 per trip to make it worth it. To put it another way, you could, with the same money, offer every motorist on that section of road up to $27 per trip, FOREVER, and if they chose that in preference to having a new road, that would be the better way to go.

  12. I found out on Thursday morning from NZTA that as a result of the “slight” re-alignment of the route, my house, which I built 5 years ago and would have become a near neighbour to the motorway under the indicative route, will now be bulldozed because it is in the way of the preferred route. So I do have an axe to grind.
    The earth works involved in this project are going to be huge and are almost certain to push the budget way out. The newly updated website shows a number of unconnected maps which tend to mask the devastating effect that this motorway will have on the area. The Fly-over” view attached to the previous newsletter showed this much clearer and in my view, NZTA are trying to gloss over this aspect to reduce the objections to the scheme. I do agree that there is an easier and more cost-effective fix to this problem and would refer you to an article that I wrote pubished in the Herald in April last year.
    The way that NZTA and the ministry have treated affected residents is nothing short of criminal and the revised information posted in their website contains huge inaccuracies and information that I know from conversations with is not true. I am due to have a meeting with NZTA on Tues 1st so may compile a guest post after that date.

  13. One way to push traffic on to the new alignment, especially if tolled, is to make the ‘old’ route less attractive for through traffic. This is quite a common tool used overseas when a new tolled route opens – you make it harder for traffic to continue to use the existing route. Typical methods used are road narrowing through lane reduction/re-allocation, adding or changing intersection controls so the existing route no longer has priority, and lowering of speed limits. In extreme cases you actually close the old route completely to through traffic – 100% migration to the new alignment then!

    In this situation it would be very easy for the NZTA to justify lowering the speed limit on the existing route, as the current speed limit on this part of SH1 does not reflect the design speed of the road – this is a big reason why the accident rate is relatively high. Lowering the speed limit will increase the average time required to use the existing SH1, letting the NZTA claim a higher time saving than would otherwise be the case, which in turn improves the quoted BCR of the new alignment.

    In terms of ramps at Mahurangi West and Puhoi: I wouldn’t mind betting that if the road is staged into 2-3 parts then the southern most section would go from the tunnels north to a point just south of Mahurangi West Road, and would link back to the existing SH1 at that point. The next section north of here will be the most expensive, trickiest and longest section to construct. If staging does happen this would be the logical point for an interchange, at least with south facing ramps, as you would basically be constructing a ‘link-in’ section which could be converted an interchange once the next section is completed. An example of this is the old motorway terminus at Grand Drive.

  14. “Perhaps the people working on it also know how stupid the project is and are trying to delay it as much as possible because if spending $760m on a road that currently carries only ~20,000 vehicles per day is bad, spending $1b on a road that carries less than 9,000 vehicles per day is just madness.”

    Another question that the Board of Inquiry process does NOT allow the board to ask. The Board will not be able to put in question the validity of the project itself, or consider whole-scale alternatives. The Board will only be able to look at whether the negative effects can be avoided or mitigated. That worked out reasonably well on Waterview, but government can still bulldoze through stupid projects if it wants to.

    And actually, why not? If the voters are too fri****in stupid to elect them again, knowing this kind of bull**** is their style, then they deserve no better than having their taxes wasted. I weep for the moronicness of it all, but we can’t say we didn’t have fair warning of this before the last election.

    1. Yeah but nobody votes on transport policy – we know that. So I don’t buy the whole “we voted for motorways” argument.

      I think it’s stupid that there’s no formal public process to determine whether this is the best option/alignment. We just get the board of inquiry process to come along and sweep up the mess and ensure environmental effects are ‘mitigated’. No wonder we get poor planning outcomes in this country if we can’t even get involved in the planning.

  15. This is how it see this Area of Golden Triangle?
    Auckland transport network – Whangarei – Auckland route
    1. Freight service: Miss W moves bulk freight between Whangarei and Southdown/Wiri. this route at its minimum has 3 pipes 1 rail / 2 roads. at its max it has 14 pipes 2 rail / 12 road (year 2022?), LOS at its narrow point. will have BELOW stable flow on holidays (4? days per year), At its widest point it will be BELOW stable flow each work day ?7:00am-9:30am? and ?2:30pm-6:00pm?. Miss W freight route takt time is based on the route having a stable flow for 18? hours per day. giving Hours Of Service (HOS) a B.
    2. Mr W has a sprint courier service between Whangarei and Manukau, with turn around time of 51/2 hours. To do this he needs the route to have a stable flow (LOS C), giving a average speed of 80 km/h. The weakest point on this route is the same as Miss W. Mr W can operate an hourly service for 18? hours per day. lets call this HOS B?
    3. Mrs W lives in Whangarei and works in Albany 2 hour commute time. Flow is unstable for about 3? evening a year. I thinking this route provides a LOS B? and HOS A for Mrs W
    Dr W lives in Wellsford works in Manukau. (1 1/2 hour commute by car with the route LOS C). Dr W chooses to drive to Albany (63km 1 hour drive including parking and wait for bus) Dr W can start work on the Bus. Note: Dr W could have driven to Helensville, A drive of 45 minutes to catch PT. But the Frequency Of Service looks to be about D?
    Question: will RoNS improve LOS or HOS for the W people.

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