Light rail will dominate next year's ACT election. Both main parties have more explaining to do

A year from now, Canberrans will decide who will represent them in the Legislative Assembly for the following four years. It will be an election unlike any since the ACT became self-governing in 1989. The Assembly is about to expand dramatically in size: from 17 members to 25, and from three electorates to five. One potential benefit will be that MLAs, representing smaller areas, will be more local in their focus; each of this city's districts will have its Assembly champions.

Yet despite the greater number of candidates and the increased localism that the new electoral system will likely encourage, one issue is set to dominate the coming election. The Canberra Liberals strongly oppose the Labor government's planned light-rail network, which is backed by the Greens, and have vowed to stop its construction if they win power. The opposition will seek to frame the 2016 election as a referendum on trams.

For at least a generation, ACT residents have debated regularly whether a rapid mass-transit system should be built in this city, and if so when and what type. Past polling on the Capital Metro project, carried out by the government and other groups, has shown Canberrans are split on the merits of building a light-rail network, at least at the moment. As expected, residents of Gungahlin and the inner north, where the first line will be built, tend to favour the project more than Canberrans who live elsewhere. Younger people tend to favour it over older voters. A consensus remains elusive.

Canberra is Australia's most car-dependent city. It's also growing more quickly than most other parts of the country. We will need transport solutions beyond more roads and more car parks. Infrastructure Australia says the costs of traffic congestion to the ACT community will soon exceed the costs of building transport alternatives.

In other words, there is a case for a rapid mass-transit system to be built in the ACT. Yet the government has not yet made it convincingly. Whether that is because Capital Metro is the wrong project, or because now is the wrong time, or because Labor and the Greens have simply failed to explain it well is for voters to decide. Chief Minister Andrew Barr has a year to sell it. A little more transparency (several reports on the project have not been made public, for no obvious reason) will no doubt help.

The Liberals, too, have a year to explain their vision; they certainly haven't to date. Saying "no" is easy but it's not an alternative for the future. The opposition has had ample time to develop a meaningful plan for this city. If it wants the privilege of governing, it must show it deserves it.

Today, The Canberra Times launches an online survey of readers on this topic. It is not an authoritative, statistically weighted poll of Canberrans' views. But it is an opportunity to take part in a discussion of this issue before we cast our votes in October 2016. We need to be sure that, come polling day, none of our questions remain unanswered.