Right now, drivers volunteer to work weekends as overtime The new network, unveiled this week, will offer faster, more frequent buses and more late-night and evening runs, with Sunday and public holiday times extended to 10pm.

Secretary for the Transport Workers Union in the ACT Klaus Pinkus said the government's promise to deliver the network by January was not impossible, but "very optimistic".

The union has been locked in enterprise bargaining with the government for the past eighteen months and no new agreement has yet been reached with drivers, Mr Pinkus said.

"They first put the idea of more [weekend and late] services on the table about a year ago, but they haven't come up with a firm proposal until now, and even now...there's been no proposal on how it will work, just a few ideas floating around."

Changing the opt-in rule was one of those ideas put forward by ACTION, which runs bus transport in Canberra, but Mr Pinkus said it would come down to what the drivers were willing to accept. If they said no or the government "overreached" on more weekend hours, running the fleet with casual staff would be very difficult, he said, and some bus frequencies might be shaved back.

A spokesman for Transport Canberra and City Services said a mix of overtime from full-time, part-time and casual drivers currently covered weekend runs but did not say whether a change to the opt-in rule was on the cards.

"These matters are part of our ongoing discussions with staff and unions as we work together to build a better transport network for Canberra," the spokesman said.

On top of recruitment carried out earlier this year, Transport Canberra confirmed was in the market for both more drivers and more buses to get the expanded system up and running.

In the years before last, Mr Pinkus said the system had struggled to find drivers willing to volunteer their time on the weekends but now the fleet was running with a full complement and weekend hours were more easily covered.

At a senate estimates hearing this week, ACT Transport Minister Meegan Fitzharris said the decision to run extra weekend services had come out of extensive community consultation and analysis of MyWay data.

"This is what people have told us they want," she said.

Calls had been growing in both the communiy and across the aisle in the assembly for longer bus times on evening, Sundays and public holidays, to better support shift workers and those unable to drive.

Along with strong demand for weekend runs, more than 40 per cent of all patronage was on the new rapid buses, Ms Fitzharris said, prompting an expansion from four to ten routes in total.

Canberra still lags behind other cities in terms of public transport use, so the new network had been designed to get more people on board, Ms Fitzharris said.

In the next two years, the ACT's electricity sector is expected to switch over to 100 per cent renewable energy, after which time reducing car travel will become crucial to meeting the territory's carbon emissions targets.

While parents groups have raised safety concerns with the new system, which will see dedicated school buses more than halved in favour of more public routes going past schools, Ms Fitzharris said it was more "equitable".

Transport Canberra director general Duncan Edghill said there were already about 3000 students using public bus interchanges every day in the ACT.

The new network would dedicate two staff to each station around school times to help make sure they got on the bus safely, though extra staff numbers were yet to be fianalised.

Mr Edghill also revealed Transport Canberra was procuring bidders for a new MyWay card as part of an eventual move to an account-based system, which would allow commuters to tap on and off with their phones or credit cards.

While MyWay would stick around until at least the launch of light rail, which will also use the cards, he flagged something "new" and exciting was coming down the line.

Have your say on the new bus network at yoursay.act.gov.au/rapid-bus-network until August 12.