The introduction of light rail as part of an integrated public transport network in Canberra could lead to a doubling of the number of commuters who leave their cars at home.
Australian National University climate change and land use expert Will Steffen told Tuesday's light rail deliberative forum that cities including Perth and Portland, Oregon had reaped health and environmental benefits from better public transport options as more people moved to rail and trams.
He said as many as 100 cities in the US were adopting light rail to improve public transport and land use, and Canberra would probably have the same increase in patronage as the full tram network was developed.
Bureau of Statistics data from March 2012 showed 7.4 per cent of ACT residents used public transport to get to work or study.
"There is a much bigger mode shift from car transport to public when you go from a bus system to a tram or light rail system," Professor Steffen said.
"I don't see why Canberra would be any different from other cities. I think as the network develops you will see more people use it – that's obvious but you can't build a whole network overnight."
More than 40 business and community leaders gathered for the forum on Tuesday, organised by the ACT government agency charged with developing light rail in Canberra.
Professor Steffen backed the planned 13-stop line from the city to Gungahlin as a wise choice for the network's first stage, due to its potential to remove cars from the road and decrease congestion through effective traffic management.
"You would expect to see mode shift pretty quickly from people who travel in for work or study, like in the public service or at ANU."
Looking towards further development, the former Department of Climate Change science adviser and climate commissioner said trams that could travel about 100km/h could be used to link ACT town centres.
Lines in the rural communities surrounding the Danish capital Copenhagen could serve as a guide for an expanded network, Professor Steffen said.
"You can get big systems, with the same vehicle or train acting as a tram in denser areas like down Northbourne Avenue with more stops and travelling at 50 or 60km/h.
"When it goes out on a longer stretch, it could go much faster."
He said the existing ACTION bus network needed to be effectively integrated with light rail, due to become operational by 2019 or 2020 after three years of construction.
"One of the problems with buses is they sometimes weave around. That's good for providing a sort of social service for people who don't have cars.
"People who have to go to work need direct and rapid services and then they don't have parking problems in the city."
University of Canberra urban planning authority Barbara Norman told the meeting light rail could bring health and environmental benefits to the capital.
She called for a community facility such as a town hall to be built at the Gungahlin end of the light rail line to encourage patronage and engagement.
Professor Norman said maintaining Canberra's approach of integrating social and public housing through the "salt and pepper" system was essential to the city's future, and called for better use of community facilities such as gardens and bike paths.