It seems likely that many more Melbourne travellers will drive cars in the foreseeable future than take public transport.

This is not necessarily the disaster that it might at first appear – improvements to the environmental and fuel efficiency of cars will make them much more environmentally friendly and offer a fair trade-off for their many advantages.

It would be a different story if Melbourne had followed the same historical development path as Manhattan.  Melbourne would then cover an area extending about 5-7km from the CBD (rather than the current 40-50km) and the great bulk of trips would be taken on foot or by public transport.  It would be infinitely more sustainable than the Melbourne we know today.

However the reality is that Melbourne is much more like greater New York than Manhattan, with extensive low density suburbs surrounding a denser core (although Melbourne’s inner city with its characteristic one and two storey terraces is a far cry from Manhattan’s ubiquitous five and six story apartment buildings).

Ironically, Melbourne’s suburbanisation was triggered around the end of the nineteenth century by the new rail and tram systems. They enabled people to choose between the very real overcrowding, pollution and danger of the inner city at that time and a larger detached house and garden on the then fringe.

The suburbs offered more space, more privacy, greener surroundings and a lifestyle that was particularly attractive to families.  Outward expansion accelerated again after WW2 when cars became more affordable and firms also began to locate in the suburbs rather than the inner city.

Public transport’s share of travel plummeted precipitously in the face of this growing competition from the car.   It now carries less than 10% of all motorised passenger trips within the metropolitan area.  Even in its area of acknowledged strength – the journey to work – public transport only accounts for 16% of all motorised commutes in Melbourne. And in any event the journey to work is now much less important – it accounts for only about one fifth of all trips.

As a consequence of low off-peak patronage, the Greenhouse Gas Intensity of rail and tram in Victoria is only around 15% better than cars per passenger km. Buses actually emit more carbon than cars.

Although owning and operating a car is expensive, it is obvious why it is overwhelmingly preferred to public transport by Melburnites.  Travellers value their time highly and are prepared to pay for convenience.  With a car, there’s no operating to a fixed schedule, no walking to a stop, no waiting at the stop, no delays and no cancellations.

It is almost always easier to use the car for the various demands of modern life, like dropping the kids off at childcare on the way to work, shopping at the supermarket, visiting mum and dad on the other side of town, commuting to work in the suburbs or going to dinner or the movies.  This is hardly surprising given that the vast majority of trip origins and destinations are dispersed across the suburbs.

A common explanation for this high level of car use is the relatively low standard of public transport in the suburbs, especially in fringe areas like the City of Casey, giving residents no choice other than to use cars.   However an examination of the City of Yarra, which includes inner city suburbs like Richmond, Collingwood, Princes Hill and Clifton Hill, shows this is a misleading argument.

The City of Yarra is about as good as it currently gets in Melbourne in terms of the level of public transport service.  It has direct access to two rail lines into the CBD and to seven reaching into the suburbs.  There are also seven tram lines.  It is right on the door step of the CBD, giving it access to a large concentration of jobs and to what is in effect a giant public transport inter-change.  Moreover, cars are handicapped by higher levels of traffic congestion than in the suburbs.

Yet notwithstanding these manifold advantages, the share of all motorised trips captured by public transport in the City of Yarra is just 21%.  The share in the adjacent City of Port Phillip, which includes the inner city suburbs of Port Melbourne and Elwood, is 16%.  Even with the highly unrealistic assumption that the conditions of the inner city could feasibly be replicated across the suburbs, this seems a very modest payoff.

Car ownership rates are also only a little lower in the inner city compared to the outer suburbs.  For example, families with children in Port Phillip earning between $26,000 and $73,000 per year own 1.6 cars on average whereas their counterparts in outer suburban Casey own 2 cars.  Much of this difference could be explained by the practical difficulties of parking even one car in the inner city.

Thus the availability of public transport, by itself, has only a limited bearing on the level of car use and car ownership.

Dramatically higher petrol prices could potentially increase public transport’s share of travel by making car use relatively more expensive (provided fares did not rise commensurately in order to help fund increased public transport capacity).  However in order to retain the advantages of private transport, it seems more likely most drivers would rationalise trips in the short term and, over time, shift to more efficient vehicles, albeit smaller and slower ones.  While the Victorian passenger fleet currently averages around 11 litres/100km, it is already possible to buy cars like the $25,000 five-seat Ford Fiesta ECOnetic diesel that uses only 3.7 litres/100km.  Further, Toyota introduced the new Australian-made Toyota Camry hybrid last month to supplement its Prius hybrid (3.9 litres/100km).

Motorists could also shift to vehicles powered by alternative fuels such as compressed natural gas.  There are already an estimated seven million vehicles in the world using this cleaner power source, including a significant number in Australia.  In the medium term it is likely motorists will also be able to use plug-in vehicles powered by electricity generated increasingly from natural gas and renewable resources.

Car manufacturers are investing heavily in anticipation of these changes – three of the world’s five largest R&D spenders are now car companies.

These adaptations would involve some compromises but align much better with the preferences of Melbourne travellers than public transport.  Most importantly, they show that the sustainability of car travel can be improved significantly without seriously compromising its advantages.  The key challenge for government at all levels then becomes to manage road traffic levels by implementing measures such as congestion pricing.

Public transport is really only a serious competitor to the car in situations where the latter’s advantages – principally time savings – are neutralised.  The key example is the city centre, where the combination of good rail and tram services on the one hand and, just as importantly, traffic congestion and high parking charges on the other, enable public transport to capture almost half of all motorised work trips to the City of Melbourne.

However while work trips to the CBD are the major market for public transport, it constitutes only a small part of the total travel task for the metropolitan area.  Moreover, 72% of Melbourne’s jobs are now located in the suburbs (more than 5 km from the centre) at very low densities.  This does not necessarily preclude a viable public transport system providing cross-suburban services, but it makes it very difficult to provide one that can compete with cars.

The cost of travelling by car will undoubtedly increase in the future and public transport is therefore likely to increase mode share (provided, as noted above, that it can contain its own costs).  However positioning public transport primarily as ‘the sustainable alternative to the car’ has led policy-makers to ignore the potential for making cars more environmentally efficient.

Policy should focus instead on improving public transport’s performance where it is most needed – for example, there is an evident need in Melbourne to improve city centre services for commuters as well as off-peak suburban services for those without access to a car.  Setting focussed targets in these areas would be more sensible than the Victorian Government’s current across-the-board target of carrying 20% of all motorised trips on public transport by 2020.

Note: this is an updated and slightly different version of an article I originally wrote for The Drum.