On Wednesday, Victorian Auditor-General Peter Frost will table his report on how effectively the government and road authorities responded.

It is expected the report will say that many of the commission's recommendations have not been implemented, including introducing variable time-of-day charging on toll roads, looking at tolling existing roads, increasing clearways, cutting the cost of off-peak public transport fares and removing incentives for state government employees to drive to work. The Napthine government is strongly pushing the multibillion-dollar east-west link as a congestion silver bullet. But many argue, including the former government, that it is impossible to build enough roads to end congestion. Even the former government's response to the 2006 report by VCEC conceded this, noting: ''Experience from around the world demonstrates that is not possible to 'build' our way out of congestion and that the benefits of new, high-cost infrastructure projects may be transitory.''

In other words, build a road and vehicles will come in even greater numbers than before. The improved traffic flow generated by the $1.39 billion upgrade of the M1 Monash/West Gate freeway is already evaporating less than three years after major works were completed; and the M80 Ring Road is already undergoing a $2.25 billion upgrade just a decade after completion. New roads cost billions and their benefits are short-lived, which is why governments attempt to get maximum use out of existing transport infrastructure - by better connections and getting people to travel to work outside peak hours. The most obvious technique for achieving this on roads is tolling, whether it is a cordon around the central business district, such as in London, or some other form of road charging using GPS technology. Some transport experts believe congestion charging is inevitable. Infrastructure Australia boss Sir Rod Eddington has been calling for a ''mature'' discussion on road pricing in Australia since 2008, and Transurban chief executive Scott Charlton told an infrastructure conference in Melbourne recently the public's attitude to road charging was changing. But adding tolls to existing roads is something neither major party has been prepared to even flirt with for fear of a voter backlash.

The Napthine government is strongly pushing the multibillion-dollar east-west link as a congestion silver bullet. But many argue, including the former government, that it is impossible to build enough roads to end congestion. When ConnectEast boss Dennis Cliche said recently the EastLink toll road operator wanted to buy the Eastern Freeway and toll it, Roads Minister Terry Mulder responded with ''Tell him he's dreaming.'' Labor's former roads minister Tim Pallas says congestion charges are inequitable. ''The transport-rich areas actually don't have to pay to use the facilities they have got and the transport-poor areas have to pay when they use their motor vehicles and enter those transport rich areas and it really just perpetuates disadvantage.'' The RACV, Victoria's peak motoring body, is willing to countenance road pricing provided other charges, including fuel taxes, are overhauled. Melbourne does have a congestion levy - a tax on car parking spaces in the CBD that will net the state government $47 million this year - but it is more a revenue stream than a traffic management tool.

Charlton argues a wider tolling system on Melbourne roads should be introduced to fund infrastructure, manage demand and promote public transport alternatives. He says roads are the last utility that does not charge according to how much you use it. He also says up to 40 per cent of travel in the afternoon peak is discretionary. But Transurban has shown little appetite for one congestion-busting policy that could shift some of that discretionary afternoon travel - reduced off-peak tolls, recommended in VCEC's 2006 report. Transurban could set variable tolls on CityLink. It does so in the United States. A network of 76 information signs inform drivers of real-time toll rates so they can make informed decisions on whether to enter tolled lanes. But VicRoads says there is no provision for off-peak tolls for CityLink in the current concession agreements with toll road operators, and any change ''would likely require compensation from the state''.

Statistics back Pallas' assertion that those in the outer suburbs are forced to drive, and to drive further, for employment. The 2011 census found people living in the outer eastern municipality of Cardinia, for example, commute a median distance of 25 kilometres to get to work, the longest in Melbourne. Selina Gilmour lives in Balnarring and works in Balwyn, where she runs a small business with her husband. She spends at least 2½ hours a day driving to and from work, - a trip of more than 80 kilometres each way. It's a commute she hates but is willing to accept to live by the sea on the Mornington Peninsula. The Mornington Peninsula has the highest percentage of residents that drive to work of all municipalities in Melbourne - 89 per cent, according to recent analysis of the 2011 census by the Department of Transport. The proportion of car commuters even increased marginally between 2006 and 2011, a period in which public transport use increased significantly. But Gilmour says that public transport is not a viable alternative for her. It would mean a drive to Bittern railway station on the Stony Point line - an irregular diesel service - then another train into the city and finally a bus out to Balwyn. ''There's no way I'd catch the train. It's so not worth it, it would take me hours to get to work,'' she says.

So she drives along Peninsula Link, the city's newest arterial road, along the length of EastLink and halfway down the Eastern Freeway to Bulleen Road. Peninsula Link has shaved 10 to 15 minutes off her commute, Gilmour says, although she is shocked at how busy it is just weeks after opening. ''It's like they need an extra third lane.'' Gilmour's 80-kilometre cross-city commute costs her some 15 hours in time and $200 in petrol each week, as well as the cost of servicing her car three or four times a year. But many Melburnians do not endure a commute as arduous and expensive as hers. About one in four live and work in the same local area, according to a 2011 report by the federal Department of Infrastructure and Transport. Transport planners view living and working in the same neighbourhood as a good thing because it cuts travel times and means job opportunities are not concentrated in the city centre.

However, in a sprawling city such as Melbourne, living and working in the same municipality does not always mean drivers won't be stuck in traffic. In the booming city of Whittlesea on Melbourne's northern outskirts, 52 per cent of residents work in the municipality or a neighbouring one. Primary school teacher Darren Peters lives in Doreen and works in Mill Park, a journey of about 13 kilometres that takes him 40 minutes. Just 2½ years ago the drive took him 20 minutes, Peters says, but in that time Whittlesea's population has grown by about 15,000. ''It's a lot of stolen time and it's very frustrating,'' says Peters, who is also a spokesman for South Morang Mernda Rail Alliance, a community group pushing for the South Morang railway line to be extended to Mernda. Yet, despite his public transport advocacy, Peters admits he gave up on Whittlesea's buses a long time ago. They are even slower and less reliable than driving, he says. Whittlesea's main north-south arterial, Plenty Road, has recently been duplicated at a cost of almost $22 million, giving residents of Doreen and Mernda two lanes in each direction where before there was one.

But Peters says the project's main effect has been to push the traffic bottleneck further south. VicRoads is already investigating building a third lane along part of Plenty Road. Navigation company TomTom released a congestion report this week that placed Melbourne fourth on the list of Australian and New Zealand cities, behind Sydney, Perth and Auckland. In the study, cities were indexed using travel times during non-congested periods, compared with travel in peak times, and the difference was expressed as a percentage increase in travel time. Melbourne scored 28 per cent. But this simple method for measuring congestion was rejected by VCEC in its 2006 report.

''One problem with defining congestion in terms of free-flowing traffic is that it does not guide policymakers towards an appropriate policy response to address congestion,'' it said. ''Expanding the road network to the point where all traffic moves at 'free flow' speeds, for example, would incur costs far in excess of the benefits.'' Graham Currie, professor of public transport at Monash University, says some congestion is good - it signals a healthy economy. But spending too much time stuck in traffic can be bad for people's mental wellbeing, as well as costing the economy, he says. However, the old method of fixing congestion - building a new road - is finished in big cities such as Melbourne, he says. ''The conventional way forward in the past has always been what we call 'predict and provide'. You predict future congestion, therefore you provide more road space. And that's been the way we've always gone.'' But Currie says there is a growing international consensus among transport experts that you can't keep on doing that.

VicRoads has begun or completed at least a dozen major road upgrades since the release of VCEC's congestion report in 2006. But as traffic continues to grow - and it has by 16 per cent in the past decade - the authority has also begun to give priority to trams, buses and even bicycles on some roads as a way of moving more people without widening roads to fit more vehicles. Meanwhile, traffic volumes continue to rise at a rapid rate on Melbourne's freeways and tollways. VicRoads traffic data shows average speeds on Melbourne's busiest road, the M1, vary from 20km/h to 60km/h in the morning peak - a modest speed for a major arterial that has just been widened at a cost of $1.39 billion. The upgrade improved flows by between 5 per cent and 20 per cent, VicRoads says. Loading But Graham Currie says all the upgrades to Melbourne's main road have ultimately generated more traffic, creating congestion that has eventually wiped out the initial time savings.

''Whenever we increase road space we increase traffic. We are not fundamentally solving the problem of congestion,'' he says.