VicRoads' long-term plan to widen Punt Road from four lanes to six, demolishing 140 properties, has been backed in a series of expert reports that found bus and tram passengers stand to gain as much from the wider road as motorists.
Public hearings begin next week into whether to preserve the 2.5-kilometre public acquisition overlay along the eastern side of Punt Road, which has been in place since 1954.
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No need to widen Punt Road
Less traffic uses the cross city street according to a long time resident and making it wider risks making it as slow as Hoddle Street.
Punt Road residents in South Yarra and Prahran want it scrapped, arguing the overlay creates uncertainty and urban blight along the infamously congested arterial route, which is used by up to 40,000 vehicles a day.
Labor flagged plans before the 2014 election to review the "50-year-old easement hovering over 140 properties on Punt Road, from Union Street to Alexandra Avenue, [which] gives locals no control over the fate of their own homes".
VicRoads wants to retain the overlay, arguing Punt Road is the only major north-south city bypass in Melbourne's inner south-east, but cannot handle forecast traffic growth with four lanes.
It argues congestion will inevitably worsen on Punt Road if nothing is done, and will further choke the surrounding transport network, including Chapel Street and St Kilda Road, three tram routes that run east-west across the road, and bus route 246, Melbourne's ninth-busiest.
Its stance is shared by Public Transport Victoria, given VicRoads' preferred long-term aim is to put dedicated bus lanes on Punt Road.
The authorities' joint position has been affirmed in a traffic engineering assessment by GTA Consultants, which concluded Punt Road was already a drag on traffic flow in Melbourne's inner south-east, and improvements were "overdue".
"The net outcome to doing nothing will be that it will impact on the way in which people access their jobs and homes," GTA Consultants' expert witness statement to the public hearing states.
The RACV also wants a six-lane road in the future, but its general manager of public policy Brian Negus argued dedicated bus lanes were not needed.
The estimated cost of widening Punt Road is about $500 million. A property analysis for VicRoads by Urbis calculated the cost of property acquisition would be $160.2 million based on 2016 prices.
Conversely, if the overlay was scrapped and VicRoads sold the 22 Punt Road properties it owns, it would reap $52.2 million, Urbis estimates, which could be reinvested in other transport projects.
The Andrews government announced this week that a permanent clearway would be put in place on Punt Road later this year.
Ten years of traffic data shows traffic volumes declined on Punt Road between 2003 and 2013, by an average 17 per cent.
But modelling predicts it will begin to rise again with population growth, to as much as 53,000 vehicles a day in 2041 if left as four lanes. Meanwhile, tram patronage on the three routes crossing Punt Road, and on St Kilda Road and Chapel Street, is forecast to almost double.
Professor Graham Currie, chair of public transport and Monash University's faculty of engineering, said a wider Punt Road would be a poor outcome for Melbourne.
"Is Hoddle Street a good contribution to Melbourne? It's an awful place," he said. "Are we going to condemn the rest of Punt Road to be like Hoddle Street?"
Professor Currie argued grade separation at major intersections would be a better solution.
Opposition planning spokesman David Davis said the public deserved to know the full range of options before the planning panel hearings start next week, including previous studies into potential tunnelling beneath Punt Road.
He said the community would never have certainty if the public acquisition overlay was left in place.
"It leaves the community hanging, it leaves the heritage properties along this strip without certainty into the future, it means that people can't renovate," Mr Davis said.