Travel times on one of Sydney's worst commuter road journeys will be slashed and the Baird government will consider a new vehicle tunnel beneath Military Road under plans set to be announced in Tuesday's state budget.
The measures affecting Pittwater, Spit and Military roads could provide relief to long-suffering motorists and potentially increase public transport use.
It is understood the government will reveal plans for an above-ground ''rapid bus transit'' system between Mona Vale and central Sydney.
Bus services between Spit Junction and Wynyard can vary from the timetable by up to 20 minutes and morning peak traffic can crawl along the Manly-Military-Spit roads arterial at an infuriating 18km/h.
It is also understood the government will fund a feasibility study into building a vehicle tunnel that would allow commuters to avoid the bumper-to-bumper grind.
Premier Mike Baird signalled on Wednesday that measures to relieve the thickened traffic artery, which passes through his electorate of Manly, were overdue.
''[The northern suburbs] have been ignored for too long … I'm happy to argue with anyone and everyone that we need these funds in our community. They will make a big difference,” he told the Mosman Daily.
Bus rapid transit systems feature frequent services and exclusive roadway or priority over other modes of transport.
A Transport for NSW pre-feasibility study in 2012 examined five options between Mona Vale and the city. They included a two-lane bus tunnel from Spit Junction to the Warringah freeway, establishing 24-hour bus lanes and widening the Spit Bridge to six lanes.
Bus lanes could flow along the kerb or down the median. Depending on the option chosen, on-street parking could be removed and roadways widened.
The study also canvassed an east-west option between Chatswood and Dee Why.
It concluded bus rapid transit measures were feasible but prioritising buses by removing general traffic lanes would lead to longer trips for other vehicles.
It is understood the government will proceed with an above-ground solution. However Mr Baird reportedly said he was ''committed to the tunnel; that remains a key objective''.
''A tunnel will deliver the most benefit in terms of travel time,'' he said. ''It will return Military Road to community use rather than transit use. It will help to take the congestion away, and that is desperately needed.''
It is unclear if the government will investigate the use of a tunnel by both cars and buses.
The announcement of a second rail crossing across the harbour has also raised the prospect that a northern beaches rail line could be back on the agenda.
Documents obtained by Fairfax Media in January using freedom of information laws show officials working on the next extensions to the city's train system saw a northern beaches line as one of the first priorities after another harbour crossing is built.
North Sydney Council has described the government's rapid bus study as ''inadequate'' because it did not consider other transport modes, including heavy and light rail.
Mayor Jilly Gibson said an above-ground bus transit system would ''create a clearway right through our villages, through Neutral Bay and Cremorne, and it would effectively kill off those villages''.
Manly mayor Jean Hay said a rail line to that suburb would bring higher densities, and would not have local support. Her council supports a bus rapid transit system, built down the middle of the road, adding ''[the road] is like a car park at the moment. It will make a huge difference as far as moving people.''