The Government has proposed contributing an estimated $3.8 billion over 30 years to fix the capital's transport woes.
It plans to meet this cost out of the National Land Transport Fund.
The project includes an extra Mt Victoria tunnel, but Transport Minister Phil Twyford said rapid transit would be prioritised.
Also included is a dual public transport spine through the central city on the Golden Mike and Waterfront Quays, Raul network improvements, and bus priority on Thornton Quay and Hutt Rd.
The Government will contribute 60 per cent of the estimated cost of the entire project, with the other 40 per cent expected to come from Wellington City Council and Greater Wellington Regional Council.
The project, which will roll out over 20 years, will include some form of rapid transit, but what form that will take has not been decided.
Without further investment in the city's transport system, it's estimated travel times by car and public transport could be up to 25 per cent longer by 2026 and the cost of congestion to the economy up as much as 50 per cent.
More than 2000 people and 50 stakeholder groups took part in consultation for LGWM.