Well, what an interesting day. The review of the CBD rail tunnel project – a process that has been ongoing since December last year – finally spat out its results. And I stress the plurality of those results, because effectively we have ended up with two reviews: one from Ministry of Transport and Treasury officials, and one from Auckland Council, Auckland Transport and their various consultants. It’s somewhat strange and interesting to compare the two reviews.
This post will look at the MoT review. I will look at Auckland Council’s review in a separate post – probably within the next day or two.
I had the advantage of attending a “technical briefing” from the key Ministry of Transport officials late this afternoon, which involved some useful discussion about how the MoT review differs from the original business case, and then how the Council’s review differs from the MoT review. The differences are very complex, and have reinforced my long-held belief that transport modelling is an incredibly dangerous and confusing process, where slight changes to ‘input assumptions’ can make a huge difference to the final results. In essence it seems as though the MoT have changed some of the assumptions from what the business case used – resulting in a much lower cost-benefit ratio. Then the Council changed some assumptions to come up with a different cost-benefit ratio again.
This is the comparison that the MoT’s review made between their review and the original business case: As you can see, there’s an absolutely massive difference between the two. From my understanding, there are two main reasons behind the reduction in transport benefits:
Firstly, the business case made the decision that rail capacity would be hit in 2024, whereas the MoT review has looked at this question in a bit more detail, and says that capacity will be reached in different years on different lines. Some of MoT’s statistics on this matter are a bit hard to believe – such as their assumption that the Eastern Line will not reach capacity, even by 2041. For the Western and Southern Lines, there’s some demand that won’t be fulfilled due to overcrowding by 2041, but MoT’s numbers yet again seem illogically low:
The other big change to the assumptions is the parking charge in the CBD that has been “inputted” to the modelling. The business case used an inflation adjusted figure of $30 a day whereas the MoT review used an inflation adjusted figure of $16 (both in 2041). Once again it seems fairly illogical to assume that parking charges will stay pretty much as they are now (only adjusting for inflation) as Auckland’s CBD grows over the next 30 years and becomes increasingly dense. Of course Auckland Council could get the ball rolling by charging market rates in their parking buildings for once!
Both these changed inputs, along with some technical changes, have had a surprisingly massive effect on the economics of the project – as you can see in the first table. Indeed, MoT’s general assumption is that the rail tunnel won’t make a particularly massive difference to travel patterns into the CBD – as can be seen from the table below:
One thing that I found particularly interesting at this afternoon’s briefing with MoT, is that when I questioned whether they had assessed whether the city centre could actually handle all those bus and car passengers in 2041 – the MoT officials admitted that they hadn’t looked at this issue. Considering that currently we have around 23,000 bus passengers entering the city at peak times, it’s an interesting question to ponder whether the street network has the capacity to handle an increase to what MoT think will happen in 2041 with or without the CBD Tunnel. I can’t quite see, even with significantly enhanced bus priority measures, how we would be able to double the number of peak time bus trips to the city centre, particularly while people in cars would also (supposedly) be able to increase from 35,000 this year to around 40,000 in 2041. I just don’t see the road capacity, particularly if Auckland Council pushes ahead with its vision for making the city centre a nicer place for people.
So I must say that overall I see some major flaws in MoT’s review as it relates to traditional transportation benefits. Now this is not necessarily because MoT has done its job wrongly, but rather that their assumptions are a bit out of date – and don’t really reflect what is likely to occur in the future as Auckland’s city centre changes. They assume that the CBD can handle a doubling of buses at peak times, while still providing enough road space to handle more cars than we have at the moment. They assume that parking charges will barely change over the next 30 years and they assume – quite counter-intuitively I think – that the rail network has sufficient capacity to serve the CBD, right up until 2041 with only relatively minor problems on the Southern and Western Lines, and without any problems on the Eastern Line. Quite critically, the MoT review also doesn’t really consider the impact of changing around the bus network so that it is based around more services feeding into the rail corridor, instead assuming that the current mess of bus operations will continue.
Fortunately, the Auckland Council review considers these issues in much more detail – as well as undertaking an extremely interesting assessment of wider economic benefits. But that will be for my next post.