This is the sixth in a series of posts based on the Campaign for Better Transport’s submission to the Puhoi to Warkworth Board of Inquiry. The full presentation is over at

In this post we take a look at what alternatives to the NZ Transport Agency’s $760m Puhoi to North Warkworth toll road have been considered.

Operation Lifesaver

It should come as no surprise to regular readers that our preferred solution is Operation Lifesaver, which is a bypass of Warkworth and upgrades of the existing route.

Design, construction and cost estimates for this were based on the NZTA’s own cost estimates.  Right up until 2008, the NZTA’s preferred option was to upgrade the existing alignment.  Luke Christensen discovered that the 2008 NLTP had $3.6m set aside for investigations into a Schedewys Hill deviation, of which $500k was actually spent.

Originally the scope of Operation Lifesaver included improvements to the Warkworth to Wellsford section of the highway, but the key improvements for the Puhoi  to Warkworth section are:

  • A bypass of Warkworth
  • Pohuehue Viaduct widening and safety improvements
  • Schedewys Hill
  • Safety upgrades

A bypass of Warkworth could be built largely within the northern part of the proposed designation:

Warkworth Bypass. NZTA proposed designation shown in red.
Warkworth Bypass. NZTA proposed designation shown in red.

Construction of the Warkworth bypass would avoid the significant environmental damage that will occur south of Perry Road if the toll road proceeds. The blue line is a new link road, and its exact position would need to be determined in consultation with residents. (Significant growth is planned for the southern part of Warkworth around Valerie Close, which is the side road north of Perry Rd on the map.)

The green line is the Matakana link road.  Without this link road, congestion at Warkworth will get significantly worse as all traffic to or from Matakana or Snells beach is forced through the Hill Street intersection.  NZTA’s proposed toll road does not include this link road.

The cost of this bypass would be similar to the 7 Km Mangatawhiri Bypass, which involved over 2,000m of culverts and ended up costing $43m all up.

Pohuehue Viaduct widening and a deviation of Schedeways Hill was covered in a 2010 response to an OIA request made by the CBT.

  • The preferred option for the Pohuehue Viaduct in 2006 was to widen it to two southbound lanes and one northbound lane, as well as upgrade the edge protection to a barrier that complies with NZTA’s standards. This was costed at $4.7m in 2006 and had a BCR of 3.2
  • Three options were investigated in 2002 for a deviation at Schedeways Hill, ranging in cost from $25.8m to $70m, with BCRs of 1.3 or 1.4.  All of these options involved a direct alignment that would cut through the ridge. (No word on the outcome of the $500k spent in 2008.)
  • In the same OIA response, a passing lane just south of Warkworth was also investigated and costed at $2.9m with a BCR of 2.1. The NZTA say this option was taken through to scheme assessment stage but was terminated following opposition from the then Rodney district council.

So all up the cost of these changes comes to $120.6m, but to be on the safe side we could double the estimate to $240m, and it would still be $520m cheaper than the NZTA’s toll road option.

To recap, this is a better alternative because:

  • Environmental impacts are minimised. There is no risk of damage to the Puhoi estuary from sediment flows, and hundreds of kauri trees will be saved.  Land owners south of Perry Road get to keep their farms intact and can continue to live in their houses.
  • At least half a billion dollars can be saved, meaning either less petrol and RUC taxes, or spending the money on more worthwhile projects such as safety upgrades in the Dome Valley or further north.
  • Construction traffic will be far less than that predicted for NZTA’s toll road
  • Work can be staged and will most likely be completed before NZTA’s forecast completion date for the toll road of 2021.
  • All users of the corridor benefit from SH1 alignment and safety upgrades. Remember at the completion of the toll road, traffic volumes on the existing SH1 will be similar, if not more, than they are today.

NZTA’s Response

In their rebuttal evidence, this is what the NZTA had to say on the Puhoi to Warkworth components of OperationLifesaver:

My assessment of the CBT options from a design and construction perspective is that they have not been adequately scoped and CBT has not considered appropriately the practical difficulties of their construction (and hence their cost).

By way of example, the route through Schedewys Hill is narrow and winding. Introducing a central median barrier would require additional road width for the barrier and an appropriate central median. Similarly, a side protection barrier would require additional shoulder width in front of the barrier in order to provide for traffic to pass stopped/ broken down vehicles. Creating this extra carriageway width would be extremely expensive and difficult to achieve, with the likelihood that extensive retaining wall construction and slope protection works would be needed in geologically unstable terrain. Additionally, the difficulties of achieving such construction in a safe manner, for both the construction workforce and motorists, would be immense. As a consequence, the cost of implementing these suggested works would in my opinion be many times that suggested in the CBT document.

The CBT document also advocates the SHl upgrade alternatives as being able to be delivered much sooner than the Project. However, the options for such works would need appropriate assessment, particularly in respect of a Warkworth bypass and any realignment at Schedewys Hill. The Transport Agency would need to obtain a new and/or widened designation and appropriate resource consent. Construction, particularly of the ‘on line’ works, would be extremely disruptive to existing traffic flows, would require multiple phase-traffic management measures and would result in a very inefficient (ie slow and costly) construction methodology and programme. From experience, I would anticipate that the necessary time period from inception of the assessment process, through to completion of the works could easily be of the order of 6-7 years.

Upon completion of the proposed upgrades,SHl would continue to suffer many of the issues currently associated with its operation, and its ability to address future traffic growth and assist economic development would be little changed. It would remain the only through route between Puhoi and Warkworth and, as such, the resilience of the State highway network to major natural events or accidents would be unchanged.

Having considered the above, it is my opinion that the CBT SHl upgrade proposals overall, as an alternative to the Project, are ill conceived and do not represent a viable option. Moreover, CBT’s assessments of the likely cost of such works are at best questionable, and I would expect actual costs to be many multiples of the CBT estimates. This expenditure would then need to be considered in light of the extent to which these upgrades meet the Project objectives. In this respect, it is my view that the overall performance of the SHl upgrades as proposed by CBT, is significantly inferior to that achieved by the Project.

At no point do the NZTA define what is meant by “overall performance”. NZTA have not carried out a benefit cost analysis for any option, including their own, let alone one that does not involve a four lane RoNS motorway standard. As discussed above, NZTA could get a very accurate handle on costs if they wanted to – they would just need to bring the costings that they have already done up to date.

The argument that construction will be disruptive to existing traffic flows understates NZTA’s recent successes.  The inline upgrade of the Newmarket viaduct, one of New Zealand’s busiest motorway sections, was achieved while being kept open, for the most part, to traffic.

Below the fold, I provide a bit of legal context to the consideration of alternatives.

Legal Context

In the Board of Inquiry context, the relevant section of the Resource Management Act is Section 171:

  • 171 (1) (b) – whether adequate consideration has been given to alternative sites, routes, or methods of undertaking the work
  • 171 (1) (c) – whether the work and designation are reasonably necessary for achieving the objectives of the requiring authority for which the designation is sought

It is clear in the legislation that the “work and designation” is quite separate to the objectives of the requiring authority (NZTA). Here is what the NZTA have supplied as their objectives for the Puhoi – North Warkworth toll road:

  •  Increase long-term corridor capacity, improve route quality and safety (eg gradient, alignment, overtaking), improve freight movement and provide resilience in the wider State highway network through the addition of a 4 lane route;
  • Increase travel time consistency and decrease travel times to and from the north end of the Johnstone’s Hill tunnels and the north end of Warkworth;
  • Alleviate congestion at Warkworth by providing a Warkworth bypass for through traffic; and
  • Ensure the Warkworth to Wellsford section of the Pūhoi to Wellsford Project is not compromised.

I’ve highlighted “through the addition of a 4 lane route” to show that the NZTA have embedded the work and designation into the objectives. Presumably they have done this so the NZTA can cite case law that establishes the Board is not to pass judgement on the merits or otherwise of the objectives.

The CBT’s argument to the Board is that the work and designation should be separate to the objectives in terms of the RMA, and therefore the Board should be free to enquire whether alternatives have been adequately considered.

Furthermore, it should be pretty clear from recent posts that the objective of alleviating congestion at Warkworth won’t be met by the project.  NZTA’s original modelling suggested that the Hill Street intersection will get considerably worse.

So is a four lane toll road reasonably necessary to achieve the NZTA’s objectives?

The chart below gives an indication of the volume of traffic in comparison with other State Highways and arterials.

Comparative traffic volumes
Comparative traffic volumes

You can see that SH1 south of Warkworth has just about the lowest traffic volume of any road compared. In a previous post, I’ve already pointed out that trips “further north” amount to just 5,930 veh/day, both directions. Total volume to all destinations on the toll road is likely to be only 6,000 veh / day when tolling and other factors are allowed for.

Given that a four lane motorway can typically handle volumes of 1,800 vehicles per hour per lane, this gives a capacity for the four lane toll road of 7,200 vehicles per hour.  The scale of the toll road clearly is not warranted now, or at any time in the foreseeable future.

In their opening address, NZTA argue that:

Case law has established that a court’s (or a Board’s in this case) review of whether there has been adequate assessment of alternatives is limited. In essence, it is whether the Transport Agency has acted arbitrarily or given only cursory consideration to alternatives.

A particular requiring authority is not required to demonstrate that it has selected the best of all available alternatives. To do so would be straying into matters of policy which fall outside the Board’s jurisdiction.

The High Court has stated that suppositious or hypothetical alternatives do not need to be considered provided there is evidence that the alternative is not merely suppositious or hypothetical.

The Transport Agency submits that its assessment of alternatives for the project was more than adequate. In particular, the Transport Agency submits that it has considered any alternative raised by submitters for which there is some evidence that the alternative is not suppositious or hypothetical. It has discounted other options in a rational and robust manner

Without providing any solid evidence in the form of a comparative benefit cost ratio, the NZTA claim that

The Transport Agency determined that an upgrade of the existing State Highway 1 would not meet the objectives of the RoNS, would have greater environmental and social effects than the preferred route, it would not provide the best value for money.

If the Board accept this argument, it is hard to see how any project put forward by the NZTA can be turned down.

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  1. I’ve highlighted “through the addition of a 4 lane route” to show that the NZTA have embedded the work and designation into the objectives. Presumably they have done this so the NZTA can cite case law that establishes the Board is not to pass judgement on the merits or otherwise of the objectives.

    But that is the objective, right? The objective of the NZTA is roads. The bigger and more expensive, the better.

    1. The point is they’ve stated a four lane road. Is that really necessary to achieve the objective? If they’d said a 16 lane road, then the Board should be able to question the necessity. Same for four lane road then.

  2. “Introducing a central median barrier would require additional road width for the barrier and an appropriate central median. Similarly, a side protection barrier would require additional shoulder width in front of the barrier in order to provide for traffic to pass stopped/ broken down vehicles. Creating this extra carriageway width would be extremely expensive and difficult to achieve, with the likelihood that extensive retaining wall construction and slope protection works would be needed in geologically unstable terrain.”

    Absolute poppycock!

    SH1 between Pukerua Bay and Paekakariki for example didn’t have a median barrier (albeit a wire one) several years ago.,174.909459&spn=0.00013,0.112267&t=m&z=14&layer=c&cbll=-41.021637,174.909459&panoid=1pMAfzWATCKn33NmLPHB1Q&cbp=12,40.86,,0,11.08

    And yet they still built it without any real shoulder for the barrier itself. Turkeys and Christmas come to mind.

    1. SH1 between Pukerua bay and Paekakariki is not a good comparison. That median wire barrier was done without widening the road, but it was done under such urgency and so quick that doing it properly was not an option. It was done urgently before there was another multiple fataility on it and NZTA cut corners. There would have been no proper design and if I recall NZTA did not want to do it as it did not meet standards. They could not widen the road either side and there was simply no other option. If I recall it was public pressure which got NZTA to proceeed. NZTA were and still are really hanging out for Transmission Gully to solve the problem of this stretch of road as “fixing” the existing road would be a major engineering challenge with the rail on one side, an unstable steep rockface behind that and the sea on the other side. Even now it has not stopped serious accidents along there, it has simply reduced the seriousness of them and stopped a few idiots.

      1. The relevant mantra at my workplace is that only the customer can call something a solution. The difference being that NZTA is empowered by its funders and allies to push transport ‘solutions’ that don’t work for the end customer group (New Zealanders) but do provide a comfortable existence for NZTA and the people getting paid behind every new project.

        1. Sam,
          NZTA’s customer is not us, the public.

          It is the MoT and the Minister of Transport and Minister of RoNS (oops, I meant Economic Development 🙂 ), period. No-one else counts or is important to be have their views considered.

  3. Yes Greg – As you rightly say NZTA is indeed the customer but I view this unjustified expenditure as a misappropriation of funds which should be put to better use. The RoNS programme may have seemed ok in the lead up the the election prior to Helen Clarks’ Government’s demise but the facts are now quite clear and National as the party of pragmatism should be leading the change of direction to embrace construction of the CRL as soon as possible. Why they persist with the stupidity of the RoNS projects and Basin Reserve flyovers is absolutely unfathomable.

    Worst of all is the enormous sums involved………………….?

  4. If the Cabinet want to spend lots of money on a quicker route – build the Wellington Airport Rail connection. This will be used by more cabinet ministers than any new road……….

  5. While we all want better public transport I fail to understand the hate for decent roads in New Zealand by some contributors to this site. New Zealands road network is as bad as its rail network. Both needs billions of dollars to make the country function properly again.
    Connecting Northland to Auckland using real roads and, fingers crossed, in the future a decent railway makes sense.

    Building a 4 lane motorway between Northland – Auckland and on to Wellington makes absolute sense.
    A country needs good infrastructure to function and NZ doesn’t have that. Making State highway 1 motorway standard on all of the North island is a definite necessity. Motorways isnt bad in the right places.

    New Zealand stopped investing in its infrastructure in the early 60ies and its really only the last 10 years we have started to do something about it. That applies to both rail and road.

    Build a big 4 lane motorway all the way to Northland and while at it build a real motorway between Auckland-Wellington and Auckland-Tauranga. Connect New Zealand. these projects are national projects that we need done. just as we need much better public transport in Auckland.

    We usually mention Europe, Vancouver etc on this site. Id think that youd find that Europe and British Columbia all have built great motorways to complement their rail networks. The ring routes round cities such as Copenhagen are great. the danes built motorways across their entire country, extremely expensive bridges, man made island etc its not just about rail, its about better transport and motorways are a key part of that.

    1. Very good points Sean. Europe is criss crossed with a superb motorway system that includes all the countries and cities often quoted here. Denmark, Nederlands, Switzerland and even the Czech Republic and Romania have motorways better than NZ.

      As roads are used by private, public, and trade transport it makes sense that the urgent priority should be the investment in road projects, after that has been solved then we can turn our thoughts to rail.

      I do not want to listen to any arguments that road is last century technology or that rail is the green alternative because both those statements are wrong. Intercity rail in NZ is fossil fuel powered and roads can and will accommodate the cars of the future, be they electric, hydrogen, or synthetic liquid fuels driven.

      So lets not get negative about the RONS, the only worry should be how we pay for all the infrastructure investment, not if it is needed or not.

      1. Despite the vast population of Europe there is a point at which road building there even becomes a foolish waste of money, see below. And here there are only 4.5million people who just cannot afford to waste precious resources on on projects than cannot be justified under proper analysis. You may well ‘feel’ that four lane roads are great, but so what?, when examined rationally, as Cam has in this series of posts, it is clear that this this is an appalling waste of money for a small economy with much more pressing calls on its limited cash, starting with a properly scaled intervention around Warkworth and upgrade for the existing route.

        ‘the only worry should be how we pay’…. Exactly; it’s so easy to say that you want more stuff, but we cannot have limitless amounts of investment in this or any other sector.

        And Sean: We have motorways, that’s all we been building, this, after all, is a duplicate road, it most certainly is time to invest more cleverly on this route, and invest equally cleverly elsewhere.

      2. So you think that we should build roads first then once we are done build pt? Great, it’s worked so well in Auckland, lets do it Nationally.

        Honestly what does someone have to hear to believe that building roads should happen before anything else regardless of value for money?

    2. Sean, you wrote “Making State highway 1 motorway standard on all of the North island is a definite necessity” – well no actually. Part of what Cameron has shown is that the road North of Warkworth is just not that busy- not even busy for a 2 lane road.
      The population a motorway to Whangarei would serve is maybe 100,000 people, and it would require a further 100km of motorway. Where in Europe do they build 4 lane motorways for 100km to serve 100,000 people?
      NZTA has tools to calculate whether it is worth building a road or not- they simply are ignoring them in this case.
      I don’t think this blog is anti-roads- just anti stupid roads. They would also be anti stupid railways.

    3. Sean, I dont think anyone is debating the need for new investment in infrastructure or in particular the need to spend money on new roads. Instead the debate is about value and as I am sure you would agree, ensuring that public money is spent on infrastructure that delivers the greatest value.

  6. Hello Sean
    I think what people are asking is has NZTA changed its Objective

    “The NZ Transport Agency is a Crown entity established under the Land Transport Management Act
    2003. The objective of the Agency is to undertake its functions in a way that contributes to an
    affordable, integrated, safe, responsive and sustainable land transport system”

    Note the word objective means “A thing aimed at or sought: goal – based on facts rather than feeling or opinions”
    If the goal is to build a big 4 lane motorway, then it NZTA needs to prove based on facts it is affordable, integrated, responsive and sustainable.
    Or it needs to change its objective to “the objective is to build safe 4 lane motorways” and remove the word affordable, responsive and sustainable.
    Is this what you’re asking for?

  7. Thanks Cameron, and others in CBT, for your hard work. It really takes a lot of energy and courage to do what you are doing.

  8. I simply don’t understand their economic development argument. Unless they are thinking like Keynes idea of burying money in a field and selling the right to dig it up again to stimulate GDP. I thought all that crap was discredited by the late 1960’s.

  9. BTW I think you are on the right track by proposing a shorter alternative that would deliver most of the benefits at a fraction of the cost. I vote for the blue option.

  10. All this is very well, but here in the Far North what we need are reliable, robust roads which don’t get closed when there is a storm. We want roads that are less subject to slips, roads that are less liable to washouts (and drainage is the answer), roads that will take the heavy traffic that the timber industry require. And when there is a road closure there must be decent alternative routes. The absence of a “Holiday Highway” may cause some delay now and then, but first things first, please. See my little website

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