Where to with transport in our capital cities?

Then there's the issue of cost. Melbourne Metro is estimated to cost $11 billion (nominal) for 9 km of tunnels and five new stations. The Melbourne suburban rail loop promised at the last election is estimated to cost $50 billion for 90 km of tracks and 15 stations. Finding funding for infrastructure on the scale necessary to significantly change mode share would be a huge challenge.

What should we do?

Let me emphasise that we must build more public transport in our cities to meet the absolute growth in patronage. We should recognise, though, that past, present and promised improvements like the Melbourne Metro and the promised suburban rail loop won't have much effect on mode shift. They'll mostly benefit those travellers who choose to use, or must use, public transport i.e. mostly city-centre workers and students.

However policy-makers should back away from framing public transport as primarily a substitute for driving. They should recognise that the urban population's long-standing and evident preference for on-demand point-to-point travel shows no sign of waning. They should acknowledge Australia's particular urban history; the benefits that capital city residents see in private travel can't be wished away ("How Ya Gonna Keep 'em Down on the Farm After They've Seen Paree?").

They should instead give greater attention to making point-to-point travel more efficient and less socially costly. That means requiring private vehicles to be significantly cleaner, smaller, slower, safer, quieter and more considerate of other users of the city than has been the case to date. The demand for road space must be moderated by more efficient pricing; we don't leave other scarce resources unpriced (including public transport!), so it's ridiculous that we don't price driving efficiently. All of these actions can be implemented by regulation with vastly lower capital costs than current policies require.

In the longer run, advances in autonomous vehicle technology might offer ways to use road space more efficiently, especially for the three quarters of all trips that aren't for work purposes. In the immediate future, though, technological improvements in small footprint vehicles like slow two-wheelers (electric bicycles/scooters) offer a promising way to provide most of the benefits of on-demand point-to-travel while minimising downsides like pollution and congestion.

The key to boosting take-up of small-footprint vehicles is to provide a safe network of segregated routes that, relative to driving, provides substantially faster, more convenient (easier parking!), and less expensive travel. Such a network would necessarily require taking road space away from cars as well as constructing purpose-built infrastructure, but the substantial social benefits should handsomely exceed the costs.

The key challenge for policy-makers isn't to eliminate the evident desire for on-demand point-to-point travel. Rather, it's to "tame" the car, find better ways of providing flexible travel, and improve public transport, especially mass transit servicing locations of concentrated activity.