The Liberals, meanwhile, have pledged to "end the neglect" of Oaks Estate following a campaign from local residents, promising to act on the township's heritage status, road safety, public housing, and bus services.

Labor has already promised to sign contracts for building the second stage, which is to travel over Commonwealth Avenue bridge to Woden, traversing 11 km. It has suggested the new route will cost about the same as the first 12 km line from Gungahlin to the city, which is costed at $710 million, but so far has not done detailed studies or costings.

Transport Minister Meegan Fitzharris said work would start immediately if Labor was returned. The design and scoping work would get the project to procurement stage. It will determine the stage two route alignment, develop the funding and financing model for the project, and determine the best procurement approach, she said.

Almost 210,000 Canberrans would live, work or study within 1 km of the Woden light rail corridor by 2041, she said.

"Planning for this growth will be vital to reducing congestion on our roads and providing commuters with a quick, practical and efficient alternative to driving their cars ... Light rail has been talked about for 100 years, and it's now or never. It has to start somewhere."

Labor is also promising a free two-month trial for everyone on its new rapid bus routes introduced midway through next year. The new "green rapid" would travel from Woden to the city via Manuka and Barton. The "black rapid" would travel from Belconnen to Gungahlin.

Labor has already promised a 12-month trial of free bus travel for concession card and seniors card holders between 10am and 4pm on weekdays.

While debate has continued about the extent to which light rail was forced on Labor by its parliamentary agreement with the Greens, Ms Fitzharris said Labor had promised before the 2012 election to "plan, finance and develop the first stage of a light rail network" with "construction estimated to commence in 2016". It was now delivering on that promise.

The light rail project is the central point of difference between Labor and Liberal this election. Both parties are now offering substantial changes to the bus service, with a swag of new routes and rapid services.

The Liberals are also promising a new lane on both sides of Northbourne Avenue dedicated to buses and a bike path down the middle of the avenue. The Liberals say they will carve five metres out of the centre strip of Northbourne Avenue, reducing it from 27 metres to 22 metres wide. Taking in the 1 metre wide bike lanes already on the edge of Northbourne, that would create 3.5 metres each side for the new bus lane.

Ms Fitzharris characterised the Liberals plan as "concreting the whole of Northbourne Avenue and turning it into an eight-lane highway with massive bus bays that will replace footpaths".

The Liberals will on Tuesday announce a package for Oaks Estate, a suburb on the edge of the NSW border, following a campaign by the Oaks Estate Progress Association.

The Liberals said they would work with heritage experts and residents to finalise the heritage protection for homes in the area - something sorely needed for residents - by introducing a grading system for heritage assessments.

The grading system would "provide greater clarity on the future treatment of properties at different levels of assessment" and would prioritise Oaks Estate, Liberal MLA Steve Doszpot said.

Mr Doszpot said the Liberals would also pay for new speed bumps and crossings in Oaks Estate from within existing road maintenance funding, in an attempt to curb hoon behaviour, and prioritise maintenance and facade works for neglected public housing units in the area.

The party would also urgently seek to "find a way to link Oaks Estate to the Action Bus Network".