Bridges covered in greenery, 25 kilometres of cycling and walking paths and better noise standards will form part of the proposed $15.8 billion North East Link, plans unveiled by the Andrews Government have revealed.

Labor has promised to build Melbourne's 26-kilometre "missing road link", connecting the Eastern Freeway and the M80 Ring Road, if it is re-elected in November.

It has now unveiled the designs for the project, which will feature twin three-lane tunnels and lowered roads in some sections, which the Government said would minimise the visual impact and create more open spaces along the route.

The proposed M80 interchange for the North East Link. ( Supplied: Victoria Police )

The tunnels, which will now be 5.3km long, will have ventilation structures positioned as far away from homes as possible, the Government said.

The road will be built with a noise standard of 63 decibels, making it one of the quietest motorways in the state.

The designs also include bridges of green space over sections of the road link, as well as extensive cycling and walking paths.

An artist impression of an upgraded section of the Eastern Freeway. ( Supplied: Victorian Government )

Roads Minister Luke Donnellan said the Government had taken community feedback into consideration during the design process.

"There's been changes in relation to new land bridges around the trenched road around Watsonia, new noise standards, more noise walls, new upgraded cycling and walking paths," he said.

"And the tunnel is now 5.3km long, so it comes up at Yallambie, which is varied from where it was previously.

"So this is very much about listening the concerns of locals … and actually accommodating those."

An artist impression of the green bridges over the lowered road at Watsonia. ( Supplied: Victorian Government )

The Opposition has said while it supports the idea of the road project it would instead revive the scrapped East West Link if it wins November's state election.

It said without that project, traffic from the North East Link would simply add to the congestion at the city end of the Eastern Freeway.

Mr Donnellan said the Government would put the project out to market within 100 days if it is re-elected, so construction can start in 2020.

Along with connecting to the Ring Road, there will be new lanes added to the existing Eastern Freeway.

There will also be a dedicated busway, with express lanes for bus services from Doncaster towards the city.

The Government has previously said it is too early to say what the toll prices for the road would be.