The wealth of documents the Ministry of Transport has published on its website in relation to the review of the CBD Rail Link project provide a unique insight into the process that has gone on throughout the review process. If only the development of all business cases (yes, I’m looking at you Puhoi-Wellsford) were able to be so openly analysed.

Much of the information is very technical, and while outside of the immediate teams involved in the review process I may have read more about this project than most people, at times the technical aspects of it can confuse me. Modelling systems like ART2, ART3, APT, the differences between them, the assumptions made in modelling that accompanied the 2005 RLTS versus the 2010 RLTS all seem pretty complicated – but it would seem that it is these very technical issues that sit behind the different outputs of the review undertaken by the Ministry of Transport and the review undertaken by Auckland Council.

One particularly important element of the whole review process was perhaps the most technical part of it: the analysis of the traffic modelling itself. Two very interesting papers to read, that form part of this review process were a February 11 Memo from the Ministry of Transport – outlining their concerns about many of the ‘assumptions’ in the business case; and then a March 2 reply to that memo from APB&B: the group of consultants that put together the original business case.

The MoT memo raises a number of concerns about some of the inputs into the traffic modelling that was undertaken in the business case. These concerns are summarised below:Reading through the Memo is more detail, it would appear as though APB&B’s assumptions in the project’s original business case were sourced from a variety of areas that did not completely match the assumptions of the 2010 Regional Land Transport Strategy.

  • The 2010 RLTS predicted a lower level of congestion in 2041 than the 2005 RLTS did: I assume largely because the 2010 RLTS was more visionary and included the completion of a lot more projects.
  • The 2010 RLTS assumed a real price of $16 a day for parking in 2041 (inflation adjusted), which APB&B thought was unrealistically low – so they used the 2005 RLTS assumption of $30 a day.
  • The two diagrams below compare the 2005 RLTS ‘bus lane map’ (on the left) with the 2010 RLTS ‘bus lane map’. The reality of what can be implemented by 2041 probably sits somewhere between the two: but MoT insisted that the 2010 RLTS assumption be used.

Changes to these assumptions seem to have contributed to the MoT’s work showing that the rail tunnel would be much less popular than anticipated by the business case: pretty obvious if MoT are saying that the streets would be less congested, parking would be cheaper and there would be more bus lanes. Whether those are realistic assumptions is what deserves further analysis – and that’s what APB&B stressed in their response to the points raised by MoT:This reinforces my key criticism of MoT’s review: that they’ve never considered whether the CBD can actually handle all those extra cars and buses. This ‘street network constraint’ was clearly in the mind of APB&B when they put together the business case input assumptions – so while they may not have been consistent with the requirements of the 2010 RLTS, I think they’re logical and justified.

In terms of parking charges, as was outlined above another key difference between MoT’s work and the original business case is whether a charge of $16 or $30 a day for 2041 (in real terms) is more realistic. Of course nobody knows the answer to this question for sure, but APB&B put up some pretty compelling arguments for using the higher figure: APB&B also note how illogical it would be for parking charges to effectively remain at their current levels for the next 30 years:Once again it seems that APB&B made some very logical and sensible decisions when choosing their assumptions. One does wonder why the modelling behind the 2010 RLTS was done with such silly assumptions.

The difference in opinion between bus lane networks surprisingly has a relatively low impact on patronage levels for the rail network. Perhaps more than anything else, that highlights the overly narrow focus of the way the project’s benefits have been calculated: largely as a “how do we get more people into the CBD” issue rather than a “what impact will this have on travel patterns right across the region” issue.

The final document produced by MoT as part of the ‘technical stream’ of the business case review highlights the various parts of the assessment of traditional transport benefits which have led to such a wide difference opening up between the original business case and their review:As you can see, the big differences do not relate to the first row – the “model outputs”, but rather to how those model outputs responded to the ‘application’ of various other factors like capacity constraints, congestion assumptions and annualisation factors. My understanding is that the parties generally accepted the annualisation issue was a technical error in the original business case, but in regards to the other two matters, there seems to still be ground for lively debate over which is more realistic.

This is what MoT say about the ‘capacity constraints’ issue: While Auckland’s new electric trains will clearly add capacity to the rail network – by being longer than our current trains – I must say I find it very difficult to believe that in 30 years time we won’t have any capacity issues on the Eastern Line and we won’t have significant capacity issues on the other two lines. Post electrification we’re only going to be able to operate six car trains every 10 minutes on the three main lines, plus two trains an hour from Onehunga. That’s not a huge boost in capacity from what we’re running now.Critically, MoT’s estimates for rail patronage with the CBD Tunnel in place that inform the figures above are lower than what was estimated in the business case. This seems to have been informed by their unrealistic optimism about the capacity of the rail network without the tunnel and their unrealistic optimism about the ability of the CBD to cope with an enormous increase in buses and car.

The raw difference in numbers is detailed below:

All the sentences in brackets, outlining the limitations of the modelling, are quite interesting.

The final factor in the table earlier in this post that leads to dramatically different transport benefits is the “Application of CBD congestion assumptions”. This is another significant area of difference, resulting from the extent to which the modelling outcomes are adjusted to reflect existing levels of congestion in the CBD and the ability to get more people into the city at peak times by measures other than the CBD Tunnel. As I’ve noted many times before, this is a fundamental difference between the Auckland position and the Central Government position: Auckland understands that it’s impossible to double the number of buses into the CBD and pile 10,000 more cars in at peak times. For some reason, the Ministry of Transport doesn’t get that.

The $52 million compares to the original business case saying that additional decongestion benefits would amount to around $350 million. So that’s a pretty big chunk of the difference.

Ultimately, it seems that the key point of difference relates to the question of “when does the rail network hit capacity?” MoT’s lower estimates of rail patronage, their enormously optimistic estimates of bus patronage and their somewhat illogical assessment of rail capacity (no capacity issues on the Eastern Line in 2041 – seriously?) have resulted in the vast difference between the level of transport benefit the business case says the project will generate and the level of transport benefit the MoT’s review reckons the project will generate.

Because many of the wider economic benefits (something I’ll look at in a future post) are simply calculated as being multipliers of the transport benefits, any differences keep on being exaggerated over time as a wider variety of benefits keep getting considered. Debates over how many additional employees will locate in the CBD due to the project obviously also has an impact on the differences between the positions.

Auckland Council and Auckland Transport’s response to these issues points out many of the same concerns about MoT’s assumptions that I have noted. They say:

Well, these criticisms seem fairly obvious. If the modelling tools assume unlimited street space for additional buses and cars, of course the calculated benefits for a rail project like this are going to be significantly lower. But the fact is that the city doesn’t have unlimited street space for additional vehicles – which is one of the main points of this project: it’s the only feasible way to significantly add transport capacity to the city centre.

Could we please have a proper review of the business case that doesn’t ignore the elephant in the room – our inability to increase CBD road capacity? Oh that’s right, that’s what Auckland Council and Auckland Transport ended up doing.

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  1. Reading through some of these documents it does make me wonder, what language is being used behind closed doors at places like APB&B as well as some of the other companies involved in the various stages of this project. I imagine it would be pretty unfaltering towards the MOT and NZTA and while I’m sure this is a competitive industry I wouldn’t be at all surprised if there was decent network behind the scenes with other companies not involved that also wouldn’t be impressed with the rubbish the MOT is pushing. Considering that many of these companies also will have done work for the government in the past, would crap like this make them consider the value of even operating in the country potentially with the companies focusing on countries more reasonable taking more highly skilled job offshore?

    Also how will this impact the airport corridor study? I assume that GHD (who are doing that study) would be looking closely at this to ensure they have these bases covered. What happens then if it comes back with a glowing recommendation for rail as the government could hardly order a review on it like this considering the NZTA and MOT are both meant to be involved in it from the start.

  2. Great work Josh, dispiriting though. It is clear that Joyce’s MoT is really a propaganda ministry. He dictates the answer and the sorry officials have to find a way to back-engineer a process to get to that outcome. Best of course to bury it in technicalities. 0.4 seems to be the magic number, that’s where Puford first came in in the supressed SAHA report only to magically become 1.1 after Joyce’s yes men were set to fiddle the numbers. Interesting the symmetry of this as 0.4 is where the CRL is now made to languish. Revenge.

    Perhaps he has culled the ministry successful down to true believers and RUF lackeys but you’ve got wonder about their self respect doing this….

    And really let’s see a ‘Do Minimum’ for Puford….

  3. people go on about how much this project would cost. but over the same period (2012-2021), how much is being spent on new motorway capex in the Auckland region? how do they justfify all that spending? mith more biased modelling, i presume?

  4. Good work Josh,

    The other key aspect to all this is that even if there was more car/bus capacity into the city (as SJ and MoT now want AT want to investigate further) its the LAST thing Auckland would want to encourage. Reason it goes against all the other initiatives slowly gaining momentum to bring the pedestrian vitality back into CBD. Its a universal concept proven world wide (we are not a unique human species down in NZ) that urban environments of successful thriving CBD’s are heavily pedestrian focused with rail (and or light rail) the backbone in getting those pedestrians there. Buses certainly have there place in feeding PT towards CBD and must integrate with rail, but a heavy bus presence in the CBD is a detraction, add the ubiquitous car and consequent many dire car park buildings to accommodate them and you are peeing into the wind if one thinks a few shared spaces will change Auckland into the pedestrian urban utopia we are all striving for – it has to be dealt with at a bigger “structural” level and that’s where the rail loop is instrumental in bringing about a vibrantly human city – then the plaza’s and shared spaces etc can capitalize on.

    1. I think what the council need to do is sit down and work with AT to determine the maximum number of vehicles that they we can have in the CBD after taking into consideration things like the city centre master plan, spatial plan etc. Once they have some solid information on just many buses and cars the CBD roads can actually support it will greatly help in refining these numbers and would most likely see the MOT’s figures blown out of the water.

  5. Just to continue the absurd discontinuities with Puford. MoT and NZTA would have us believe that this road, between two existing ones, will transform Northland’s economy by shaving some 10 mins off a 3 to 4 hour trip. Well by that argument imagine what taking that same amount of time off a 40 or 30 min commute to the country’s premier business hub will do? Slashing travel time by a third or a quarter, well if Puford did that it might be worth building…. Either time savings are valuable or they are not, and by proportion the CRL delivers in ways that none of Joyce’s crazy pet projects can even begin to approach. Apples with apples please. Crook.

  6. The original APB&B business case for the rail tunnel (Nov. 2010) emphasises pedestrian safety and amenity again and again, and points out that this is inconsistent with both high bus volumes and high voumes of general traffic, in lines with all modern urban thinking outside NZ. The MOT review doesn’t mention pedestrians, amenity or safety at all.
    This omission is very revealing as to the difference of perspectives or “technical frame” as organisational psychologists call it. In other words, for MOT / Treasury it’s all about vehicle movement, for APB&B it’s t least partly about creating a more attractive and safer destination.
    (Even so you would have thought that MOT would have said SOMETHING about pedestrian safety, but apparently not.)
    What this reveals is that APB&B “frame” the problem in urbanist terms while Treasury / MOT “frame” it in essentially rural-state-highway terms that privilege vehicle movement, as if the Isthmus of Tamaki and the Auckland CBD were an obstacle to the state highway network in exactly the same fashion as some hill near Taihape that needs a cutting put through it.
    That might not be quite literally true, but it is true enough that they don’t pick up on the significance of the pedestrian argument. They say “oh that’s interesting” and turn the page and forget about it.
    Likewise if we were getting the cops to solve the problem, they might be looking for somebody to arrest for causing the obstruction, and might recommend all kinds of strict enforcement policies to keep unwanted people out of the CBD.
    If what you’ve got in your hand is a hammer, the problem looks like a nail.
    The significance of such (generally non-self-aware) technical framings cannot be overstated at the bureaucratic level, even if they are by no means the whole, political story.

  7. PS I should add that what you then do in a case like this get some kind of facilitator in to sort things out in a context where it is made explicit that people are coming at this from different angles. It’s a bit like the old Edward De Bono what colour is your hat idea. What you don’t want is more endless arguments about decimal points and people talking past each other.

  8. Have OIAed the MoT to see who they actually consulted about their review. I can’t imagine they have done too much similar work themselves, and their is much more experience in the international consultancies than MoT.
    As for treasury….
    Also re- the bus lane network. Have they actually costed that? Shows buslanes along all motorway corridors.
    If these are bus shoulder lanes we know they make negligible difference, hence they shouldnt count against rail benefits. If they are fully seperated bus-lanes know they cost 100’s of millions of dollars, probably billions if they do a proper job for the whole of SH20/SH16.
    Either way there are some bad assumptions made here.

  9. I take a different view. Who do we trust? Public servants who have never given us a reason to doubt their professionalism, who’se everyday business is either revewiwing business cases or providing transport advice, or consultants who have been specifically commissioned to make the rail loop business case stake up? You accuse the government of having a predetermined outcome. But the rail link is in the national infrastructure plan and I never heard any transport minitry, transport agency, or Treasury person say the rail loop was a bad idea beforehand. I challenge you to prove otherwise. Actually these agencies didnt say the tunnel was a bad idea, they said the costs exceed the nemefits at this point in time. THey were the ones who said protect the route. I would suggest we turn our attention to the fxxkwits in the council and their transport arm who put a loose and flawed business case to the government. Some questions. Why were there so many errors in a $5m business case. Why didnt all the consultants pick these up? PWC was paid handsomely to peer review, were they asleep at the wheel? Why didnt council consult with governement in the preparation of the case? Why did the council change it mind mid wat through and post this new policy case with different figures so late in the day? Was anyone in charge for managing this train wreck? Lets get this back on track but not being led ;pca; pfficials who clearly are not up to the job.

    1. It’s not a matter of which expert to trust. That’s only relevant when there’s no possible way of knowing why they come to different outcomes. We can see exactly why they come to different positions (detailed in above post and other posts) so we have the opportunity to examine which set of assumptions is more plausible.

      That said, definitely the business case wasn’t perfect and I can’t understand why there wasn’t more discussion between MoT/Treasury and AC/AT before publishing the business case. That could have avoided a lot of this mess playing out in public.

    2. Errr? Really? On what do you base the ‘never given any reason to doubt their professionalism’ idea? MoT and NZTA give us every reason to believe they are riven with an institutionalised pro-road bias and the details of both this document and the RoNS BCRs amplify that view. They are under pressure from a minister whose prejudices are well known and working under a culture that is constantly telling them that they are worthless and expendable. So no pressure there then to please the boss?

      Perhaps they believe it, see Chris Harris above, but perhaps they also want to keep their jobs…..

  10. Would those be the same public servants who produced the business cases for the RoNS, had them peer reviewed by SAHA international who in the case of P2W found inaccuracies which meant the BCR changed from 0.7-1.2 down to 0.4, the Waikato expressway went from 1.1 to 0.5 and the WNC went from 0.9-1.04 down to 0.6 (funny how P2W and WNC were just ranges rather than a set number indicating that they new the result was crap). After that they tried to bury the report and it only came to light after it was effectively leaked out. Those same officials then went on tweaking the numbers on some of these till they got the result they wanted which was what they are now using to justify.

    Also at least in the case of P2W the business case was produced before they had even worked out where the road would go and how much it would cost. Their costings used to based the result agains basically resulted from them saying Alpurt cost X amount so we will just multiply that by that by the distance even though the terrain they are going through is trickier and therefore more costly. To date they haven’t even announced that they have been able to find a route from Warkworth through to Wellsford because of how tricky the terrain is. Are they also the same public servants who claim the time savings from Puhoi to Warkworth mean that cars would have to travel at 140kph to achieve them (based on real world timings of how long the current route actually takes).

    Sorry but those international companies have big reputations to maintain and comparing them to unnamed officials accountable only to a minister who had already publicly expressed his dislike of the project I know who I would back.

  11. In a country where perhaps 95% of transport is via roads, how can the Ministry of TRANSPORT, review a transport project assuming no road capacity constraints? Have they never considered road capacity in a project before?

    Either the MoT is employing people unqualified to do their job (perhaps all the good staff are too busy on RoNS?) or this is a political review and not an impartial review by civil servants.

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