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.
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:
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.
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.
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.
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.