Why is it that whenever anyone asks about the funding of roads they end up getting a report that reads like 1960s' science fiction?
Kevin Rudd didn't expect it when he asked the Henry tax review to examine roads. It found that fuel tax was on the way out. New developments in technology mean increasing numbers of cars don't use fuel. Henry suggested ''telematics'', where each vehicle reported its trips to a central computer that charged its owners per kilometre driven.
Four years on Tony Abbott has been ambushed by the same suggestion. He asked the Productivity Commission to inquire into the financing of public infrastructure. He wants more of the funds to come from the private sector. Instead the commission's draft report released on Thursday found that private financing was ''not a magic pudding'' and recommended a trial of telematics. Abbott backed away quickly. Telematics was ''not something this government is considering''.
But it keeps being suggested because it's the right answer. When Abbott's ''Son-of-Henry'' tax review gets under way shortly it will probably suggest it as well. And it's far from the only confronting common sense suggestion in the draft report.
Its starting point is that we probably don't need as many new freeways and toll roads (and rail lines and desalination plants) as we think we do. It says we should first work out what we want to achieve (such as moving cars quickly) and then work out the cheapest means of achieving it. It might be congestion taxes or priority lanes for cars with three or more passengers.
It points to the national broadband network as a classic example of what not to do. Rudd developed a solution without first identifying the nature of the problem and considering whether there were cheaper ways of solving it. When none of the companies bidding to build the NBN handed in acceptable tenders Rudd decided to build a grander one with government funds at 10 times the cost. At every turn Rudd blocked attempts to compare costs and benefits.
If governments decide they should build something, ultimately the private sector won't be much help. It's not where the money comes from. In the end it can come from only four sources, according to the commission: user charges; user-specific taxes; general taxes; and (rarely) philanthropy.
Private sector funds have to come from somewhere, and to the extent that they are borrowed at high interest rates they will be more expensive than public funds.
Governments love public-private partnerships (PPPs). Victoria has 23 of them. But they are a sleight of hand.
''There is a perception that they offer a way to increase the provision of public infrastructure without drawing on a government's purse, thereby circumventing budgetary and borrowing constraints,'' the commission says.
In reality the money has to come from somewhere, either from charges or tax, but shifted in time in an effort to enable governments to keep their AAA credit ratings.
''There are benefits to maintaining a AAA credit rating,'' the commission says. ''However, there may be situations where public financing of infrastructure would be more efficient and welfare enhancing than either obtaining private financing or not providing the infrastructure.
''In these circumstances, it is in the community's interest for governments to weigh up all considerations and not just focus on credit rating concerns.''
The commission believes governments have plenty of scope to borrow more for worthwhile projects even if their credit ratings slip, and believes they probably wouldn't slip any more than if they had signed up for a PPP. Ratings agencies see through them.
And the commission has little time for the related fad of ''recycling''. Joe Hockey talks about it as a magic ingredient of this year's federal budget. Victoria's Michael O'Brien wants to do it with the Port of Melbourne. NSW is the pioneer, funding roads then selling them and funding more roads with the proceeds.
''It involves two decisions that should be considered independently,'' the commission says. ''First, whether a government-owned asset should be sold; and second, whether the government should procure new infrastructure.''
The commission has no doubt that ports and electricity generators should be sold. But it believes the arguments stand on their own. They are to do with who would best manage the assets rather than whether the proceeds should be plundered.
Asked to endorse the fashionable view that high labour costs and restrictive practices are pushing up the cost of big projects, the commission largely refuses.
''There is no single culprit,'' it says. ''Labour costs have risen steeply, particularly for (largely non-unionised) engineering design and consulting services, but so too have material input prices. For the construction industry as a whole the labour share of total costs has not changed appreciably over the past two decades.''
It's an uncommonly calm and uncommonly forward-looking assessment of the way Abbott and the states can go about building the things we need. All the more so because it's not what he expected.
Peter Martin is economics editor of The Age.
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