An article in Friday’s NZ Herald noted that someone called Tony Randle had taken a detailed look at the business case for the City Rail Link, and by re-analysing the numbers has come to the conclusion that a bus tunnel option (which was looked at in the business case)
Tony Randle believes a business case for Auckland’s $2.4 billion central city rail tunnel proposal under-cooked the costs to make it look more attractive than an underground bus system serving more people.
He said presumed costs of a bus tunnel considered in the business case were exaggerated…
…The $5 million business case, commissioned by KiwiRail and the former Auckland Regional Transport Authority, said a 3.5km rail tunnel from western Britomart to Mt Eden could be built for 60 per cent of the cost of a 3km bus version.
But Mr Randle said that was largely because of the “unjustified and undocumented” inclusion of a duplicate bus tunnel and nine extra busways, and a failure to provide for extra bus passengers to complement the rail project.
This assessment is pretty unusually detailed – you can read the whole thing here – so it’s worth looking at in a bit more detail. Here’s some more from the Herald article:
Mr Randle has prepared an 89-page critique of the rail project in his spare time assisted with data which he said he received from Auckland Transport only after the Ombudsman intervened.
He said the net present cost of a rail tunnel, estimated in the business case at $1.52 billion, worked out at $2.24 billion if a realistic level of bus infrastructure was added and operating cost errors rectified.
The net cost of a bus tunnel would be $1.85 billion, compared with the business case estimate of $2.64 billion.
Mr Randle said the rail tunnel had been assessed in isolation, without assuming investment for a doubling of bus passengers needed even if the trains carried a capacity of 24,900 people through it a day.
Bus patronage into central Auckland was predicted to grow from 23,180 passengers a day to 42,814 by 2041 even if a rail tunnel is built.
A more realistic bus tunnel option would be much fairer in providing a rapid transit service to more commuters across more of Auckland than any rail system.
As I said above, a bus tunnel option was looked at in the initial business case. The rough location for the tunnel is shown below: linking the Northern Busway with a pile of bus routes at its southern end: The bus tunnel’s operation was described in the Business Case’s alternatives assessment as follows:
A two-lane CBD bus tunnel would have ample capacity to accommodate the expected up to 534 bus movements per hour (two directions) assuming no crashes or breakdowns. The capacity constraint for the bus tunnel would be the operation of the bus stations as well as the level of traffic congestion on the shared road corridors beyond the tunnel. Efficient operation of the bus stations would be critical and would require active management of bus and pedestrian movements. Bus stations of this type are proven technology in New Zealand, though operating costs are high.
However a bus tunnel of this length would require safe exits in the case of fire, necessitating fire-proof separation. Each separate direction would then need to allow passing in the case of breakdowns, so would probably need to be two lanes, implying two by two-lane tunnels.
Extensive bus tunnels on the other hand are not used to date in New Zealand. In contrast to surface streets where options may exist for buses to bypass congestion, crashes or broken down buses, this may not be possible in a two-lane tunnel, so the efficient operation of the underground facilities would be susceptible to breakdowns and other incidents. In Seattle for example, a single bus breakdown has blocked southbound bus operations for 40 minutes during peak times.
One of the big issues raised in Mr Randle’s report was that he couldn’t understand why the bus tunnel had been costed at the price of two two-lane tunnels. The paragraphs above explain the reason for this pretty well I think. The real issue with a bus tunnel is what you do at the southern end of it with all those 500-odd buses an hour (things are handled fairly well at the northern end with the Northern Busway). The Business Case says that the following would be necessary: When I first read through the Business Case the bus tunnel idea had me quite intrigued – that was until I saw the map above. Constructing a full blown busway along New North Road all the way out to Mt Albert and down Great South Road all the way to the Harp of Erin, just past Greenlane. That includes a full busway through Newmarket, which seems a bit hard to envisage. Not only would these busways be incredibly expensive, their urban impacts would be pretty severe. It’s also pretty dumb to duplicate the existing rapid transit corridors to the west and south (those being the railway lines).
Along with the cost of the bus tunnel, the other main point raised by Mr Randle is the issue of what extra bus infrastructure will be needed if the rail tunnel is built. He argues that the business case says very little about how an additional 19,000 bus users will get into town at peak times above current numbers, even if the rail tunnel is built: I actually agree that the business case has a problem here. If the number of bus travellers into the city centre is going to more than double by 2041 – even with the City Rail Link – then that’s not going to work without significant extra bus infrastructure. However, I don’t necessarily think the answer is building more bus infrastructure – especially to the south and west – but rather to reconsider how we operate our bus services from these areas. After all, if we’re going to invest around $2 billion in our rail network then we’d be stupid to continue to undermine this investment by running a huge number of buses the duplicate our rail services – so obviously we’d turn many of those route (especially the long-haul ones) into feeder routes, where people would transfer onto the rail network.
So ultimately I don’t think that we would necessarily see another 19,000 bus passengers by 2041 with the City Rail Link in place. It seems to me that most additional patronage would come from the North Shore (potentially highlighting the need for North Shore rail if the city can’t cope with that many buses) and from inner parts of the isthmus, which may require routes like Dominion Road to be upgraded to light-rail if it can’t cope with the additional buses. What we don’t need are busways duplicating the inner parts of the southern and western lines – which is what Mr Randle’s document suggests: While Mr Randle’s assessment points out a flaw in the project’s business case, that it says we’re going to have nearly 20,000 more bus passengers into the CBD without highlighting how we’re going to deal with those passengers, I think ultimately his analysis falls into the same trap as the Ministry of Transport’s review of the project – they assume that bus numbers can and will increase without constraints. The Ministry of Transport preferred the surface bus option, without realising that the city’s streets don’t actually have unlimited capacity to cope with buses (or to question whether we might want 1000 buses an hour grinding along Fanshawe, Albert & Symonds Street). Mr Randle’s point is a little smarter, but once again misses the point (though so did the original business case) that the number of people on buses isn’t just a natural outcome, but something we can influence. If we want to cap the number of buses entering the city centre at peak times then we can, shifting more to feeder buses.
Ultimately a bus tunnel isn’t a sensible option because it puts more traffic onto our roads, particularly those arterials to the south of the tunnel, rather than the rail tunnel which eases pressure on the roads. A rail tunnel can unlock latent capacity throughout the entire network, enabling all that existing infrastructure to be used much more efficiently – rather than something which requires us to duplicate huge chunks of our rapid transit system.