By way of Harry Clarke's blog Kalimna, I've come across this week-old opinion piece from Professor Sinclair Davidson in The Age (also recycled in Drive.com.au), in which he poses the question "Is congestion a genuine concern, or just a Government revenue grab?"
I, like Professor Clarke, had some trouble coming to grips with what Professor Davidson meant by this:
Many of the "solutions" to congestion assume it is caused by excess demand for the road. But much congestion is caused by reduced road supply.
Where the blame lies?
But reading further it becomes pretty obvious where Sinclair reckons the problem arises:
In a 2005 US study, the Federal Highway Administration found that 60 per cent of congestion was due to the traffic authorities… The Bracks Government has introduced lower speed limits, especially around schools and in the suburbs. We're being constantly told to "Wipe off five". The inner city, already well served by public transport, has seen the construction of mega tram stops, and the King Street overpass was demolished. Small wonder travel times have increased.
This is an appalling line of argument. To deride road safety initiatives and public transport as "causes" of congestion is mischievous in the extreme. In any case, these are not things that "reduce road supply". Let's unpack a few of Davidson's claims:
- Lower speed limits in school zones generally only apply during drop-off and pick-up hours – and at those times it's not the speed limit that causes congestion, it's the sheer bloody number of parents in 4WDs jostling for prime position by the schoolyard gate.
- The "Wipe off 5" campaign is not about reducing speed limits rather it's about obeying speed limits and driving to suit the conditions:
The aim of the Wipe off 5 campaign was to dispel the myth that pushing the speed limit by 5 to 10 km/h is "safe" and highlight that even low-level speeding can have tragic consequences. Particularly for vulnerable road-users, such as cyclists and pedestrians, small differences in travelling speed can make the difference between life and death.
And as Clarke rightly points out:Speed limits will have little impact on traffic flows under congested conditions because the traffic itself is moving so slow.
hzzhzkh:3
- And it's a cute idea to blame congestion on public transport. Hmm, let's look at road space occupied per passenger: tram vs car… Game over, I think.
Hyperbolic
Professor Davidson continues:
Melbourne is forever having special events that disrupt traffic.
Utter bollocks. I just love hyperbole and exaggeration as a substitute for reasoned argument.
This, of course, highlights a neglected consideration: what are the benefits of congestion? Congestion is the by-product of a mobile population living in a city. People travelling for work, shopping, and play cause congestion. Would those who bemoan congestion want an immobile population?
A by-product? More like a direct result. And although I am not one who bemoans congestion (as a commuting cyclist it rarely has any effect on me) I do not want an immobile population or a lifeless CBD – I want a population that is mobile in a variety of ways not just one bum per car.
I don't always agree with Harry Clarke, but on this one I'm standing in his corner:
This is unsound economics and Sinclair should know better. People who travel on roads impose congestion costs on others. As has been known for at least half a century, attempts to internalise all such costs makes a community better-off in the sense that the value of the revenues gains exceeds costs to both the 'tolled-off' (those ending road use) and the 'tolled-on' (those who continue but who must pay the toll).
RMIT drive-in
It's well known that parking at RMIT University is strictly limited, actually it's "restricted to a small number of spaces for deliveries and for staff whose employment package includes a car space" [emphasis added]. As Dean (Research & Innovation) one can hardly imagine that Sinclair's package doesn't include a parking space. So I'm willing to bet that he inflicts an externality on other road users every morning as he exercises his right to park in his space at the City Campus – despite the fact of all the universities in Melbourne, RMIT University's main campus has the best access to public transport.
Professor Davidson's attitude seems to be typical of the sort of motorist who can't accept that when it comes to traffic congestion, they are a part of their own problem. One can almost see him seething behind the wheel and grumbling about all these other bastards in his way – and, of course, the Government's "revenue raising" stunts like school zone speed limits and "Wipe off 5" campaign. But he won't consider his own contribution to the situation. The fact that he's a highly qualified economist makes his views all the more incongruous and ridiculous.
The point that Harry Clarke makes is that from an economist's standpoint (and I don't presume to occupy that position) it is poor reasoning to focus only on the supply side and ignore demand:
Excess demand here is the demand for road travel less the supply of road travel opportunities. If this is excessive it could be due to either excessive demand or deficient supply. Indeed it doesn't make sense to pose things in these terms - it is analogous to the economist Alfred Marshall's difficulty of trying to work out which blade of the pair of scissors cuts a piece of paper.
I like that scissors analogy, not least of which because it helps to visualise the textbook supply-demand curve – and reminds us not to forget both sides of the supply-demand equation.
To exercise this idea on one of pedaller's examples, when the weather is wet road supply can indeed be reduced by the increased incidence of motor vehicle accidents. But demand also increases as people who might otherwise take another form of transport may tend to opt for the shelter of their private car. On that miraculous rainy day when there are no crashes, traffic congestion will still be worse simply because of the increased demand.
While Clarke is disgruntled at Davidson's sloppy economics, I'm annoyed by his plain selfish line of argument. I don't think it's a good idea to argue for a relaxation of road rules directed at safety on the spurious notion that this will increase supply of road space. His (possibly deliberate) misunderstanding of what the "Wipe off 5" campaign is about is particularly twisted: "See, the government keeps wanting us to travel slower!" - no Sinclair, the government (and might I add, other road users) only wants you to travel within the legally sanctioned speed limits.
As for major events disrupting traffic, some say that Melbourne-based politicians are in love with major events but even when the "'calendar full' sign goes up", there still isn't daily traffic disruption as a result. And to say otherwise is just pointless griping.
Alas, with such a heavy emphasis on the supply side and a peculiar neglect of demand, Professor Davidson was never going to argue for anything so demand-oriented as a congestion toll. At least not until he gets the elimination of school zone speed limits, the demolition of super tram stops, and the reinstatement of the King Street overpass – all to no avail because demand will still exceed supply.
Isn't reduced road supply one way of making people get out of their cars and onto their bikes?
'one can hardly imagine that Sinclair's package doesn't include a parking space.'
Actually, it doesn't include a parking space. Nice try.
Comments
I'm not entirely sure that Davidson's reduced-supply was entirely ridiculous, but perhaps he could have chosen better examples rather then taking the easy academic track of using somebody elses research. In Sydney, wet weather tends to have the effect of creating conditions for increased number of accidents, which effectively limit the road supply and increase traffic congestion, similarly every new bus lane marked on a pre-existing road without widening the road results in reduced road supply. There seems to be no doubt that demand for roads has increased each year, and that demand fluctuates throughout the year, eg, notable reductions during school holidays and over the Christmas period in cities.
What I was waiting for was the climax in which he advocated placing a cost on roads in order to re-establish an equilibrium position between supply and demand. Like a congestion tax or a toll on every road.