Rob Rattenbury: The problem with improving NZ's rail system

Regional rail to get moving. The Green Party's transport plan includes extending passenger rail services from Wellington to Whanganui. Photo / File

OPINION

As I have said before, the one thing I liked about the Labour/NZ First coalition and the support of the Green party was the common belief of all three parties in making the most of our under-developed and under-used railway system. Building railways in New Zealand has always been hugely expensive due to the topography of our mountainous country.

We could never have a rail system similar to Britain's even if our population was remotely similar.

Railways helped to open up colonial New Zealand to settlement but then many lines foundered due to the lack of planned population increase.

Railways must pay their way and this has always been an issue with the rail system in this country. The land is dotted with abandoned railways following abandoned dreams of what might have been.

If some railways had not been abandoned, but pushed through, such as the Nelson-West Coast line or the Gisborne-Whakatane line what a difference this could have made in time to those still isolated areas of New Zealand.

I find that sad but understand the issues around having a national railway network in a country that is bigger in land mass than Britain but with about eight per cent of the population.

I have read the Green Party transport policy, especially the bits about development of rail with inter-city connections around the south of the North Island, Christchurch and the Golden Triangle.

All very impressive, rapid passenger trains travelling between provincial centres would be just the ticket in lowering traffic volume on provincial highways if New Zealanders were of a mind to use the trains, even if free for the young and old.

My idea of rapid passenger travel is 160 to 250km/h at least, common in Britain, Japan and Europe among other places. This could be expensive.

The rail gauge or gap between the rails used in New Zealand, 1067 mm or narrow gauge, compared to 1435 mm or standard gauge used elsewhere in the world, could prevent the planned super-fast trains from operating here.

The maximum safe speed on New Zealand's narrow gauge railway would be 100km/h or thereabouts, but really only on the straight bits.

Looking towards Makirikiri Rd for site of new train yards near Marton. Photo / file

Our rail system is, by its very nature, quite bendy due to having to traverse river valleys, canyons, mountain ranges and swamps, back to that pesky topography issue. This is the reason the narrow gauge was first introduced in the 19th Century.

This brings up a very expensive point. New Zealand could have to re-gauge to 1435 mm to simply handle the increased speeds.

This would be hugely expensive, virtually re-laying the entire rail system, widening tunnels, buying new trains; the old ones would not fit unless modified, re-building and widening bridges, the list is endless.

The next big ticket item would be how you operate fast passenger trains on a shared network with slow goods trains. With signalling and loops this is possible but the delays to goods transit could make it non-competitive compared to road transport.

So does New Zealand either double or triple track the mainly single track system we now have in many parts of the country including the main railway route out of Wellington between Pukerua Bay and Paekakariki.

This could allow the system used in Britain, slow trains in the inside track and fast inter-city trains on the outside tracks.

It could be done of course but how would the country pay for it as well as maintain our current standard of living, pay off Covid-19 induced debt and balance the books?

The idea is highly aspirational and exciting in terms of changing the transport network of this country but again I compare New Zealand with Britain.

The UK is building high speed rail (HS2) at huge expense to cater for travel between the conurbations of London and Birmingham with Stage 1 due for completion in 2028, Stage 2 extending to Leeds, Manchester and Wigan.

The figures quoted to make this happen are eye-watering, even for the British public to digest. Trains will travel at 400km/h. The cost to date is estimated at £105 billion or NZ$206 billion.

Rob Rattenbury.

Birmingham is only 160km from London, a bit further than Palmerston North from Wellington.

Admittedly there are two stages to the project but costs are expected to climb as completion of Stage 2 is not due until near 2040.

Where does this leave the Greens' bold plan? Probably on the drawing board for many years to come, competing against the very real issues of health, education, climate change, debt servicing and all the other day-to-day budget items of running a small, wealthy but under-populated country with a terrain that does not lend itself to high-speed rail.

At least it is a plan though.