ADELAIDE is rattling towards a pretty difficult T-junction. We either follow the major eastern seaboard cities and introduce toll roads with all their faults and benefits, or we continue to potter along with no tolls on an ageing and crowded road network.
Traffic congestion in Adelaide and the major arterial roads is going to get worse. 
For example, in 2011 there were 7.2 vehicles for every 10 people in Australia. By 2030, just 14 years away, that ratio will be 9.7 vehicles for every 10 people - almost one for every Australian.
In 2005, road congestion cost Australia $9.4 billion. By 2020 - six years away - congestion will cost $20.4 billion.
These costs are your costs. It might be the cost of delivering food to supermarkets, getting livestock or grain to market, or the time it takes you to get to and from work, for your plumber to arrive or the new carpet to be delivered.
The introduction of toll roads would help make Adelaide's transport system - and specifically, the road network - more efficient.
It wouldn't solve everything, but it would help.
You only need to see the tunnels, bridges and flyovers that have revolutionised traffic flow in Melbourne and Sydney to appreciate the benefits of toll roads and the work private investors would be prepared to carry out if they could tap into toll road revenue in SA.
A survey by accountants Ernst and Young into the NSW toll road system found that their total economic benefit to the NSW economy was $22.7 billion.
By 2020, the system will increase the gross state product in NSW by $3.4 billion, based on private consumption, real investment and overseas trade.
Ernst and Young found toll roads reduced travel time by 19 per cent, lowered vehicle operating costs by 20 per cent and cut accidents by 41 per cent, with the inevitable cut in deaths, injury and medical and loss work costs.
The environmental value of cutting gas emissions and noise is worth $1.1 billion.
It is hard to see how, on a per capita basis, similar gains would not be made in SA.
In a perfect world I would be a hostile opponent of toll roads. They are intrusive, expensive and confusing. Even with automatic E-tickets they are a costly nuisance. They are little more than a new tax on motorists, and in turn the broader community.
They tend to hit hardest those who can least afford them and discriminate against people in outlying suburbs.
But as a society struggling with budget pressures, it is time we had a sensible debate on their merits and faults.
Until now, both major political parties have wiped their hands of toll roads. Of course they are a political tar baby - touch them and you invite trouble. Any party that advocated toll roads would be all but unelectable.
But how long can this childish denial go on when the potential benefits are so apparent?
The Department of Transport says $152 million a year would be generated if the Southern and Northern Expressways, the Port Road Expressway and the South Road Superway were made toll roads. This would increase to $310 million by 2030.
One day toll roads must come. And when they do some of Adelaide worst motoring hot spots will be eradicated by tunnels, bridges and flyovers, built largely by private enterprise and paid for by the drivers who most often use them.
Toll roads are not the ideal solution to Adelaide's worsening traffic problems but they offer a way forward.
It's time SA had a serious debate about them.What do you think?