Andrew Fender, chairman of the Transport for Greater Manchester Committee, has written to leaders of local authorities in the region urging them to back the high speed rail project.
Current proposals for the national high speed Y-shaped rail network linking London to Birmingham, then branching out to Manchester and Leeds, are being considered by the government.
Transport for Greater Manchester said the HS2 project would allow at least 14 additional services to the North West every hour, on longer trains, travelling up to 250 miles an hour, carrying up to 1,100 passengers.
Fender said: "High speed rail is not simply about quicker connections to the south and the economic benefits that this would bring.
"It would also take a significant amount of demand off our regional network which, in turn, would reinvigorate local services which provide essential connections that underpin the northern economy.
"How many of us could cope without the M6 now? Because high speed rail has exactly the same economic significance as the motorway network that we all now take for granted every day.
"This is a once-in-a-lifetime opportunity to build for our future and we don't want to miss it."
Fender is asking every local authority in the North West to pass formal resolutions in support and respond positively to the government's consultation before its deadline on 29 July.
Construction consultancy Davis Langdon was appointed by the Government's advisory body HS2 in June to produce a cost and risk model for the project.
In his letter, Fender adds: "It has been the long term view of politicians both nationally and locally that there is a real need to rebalance the economy outside of the South East. As the second largest economy outside of the South East, the North West is amongst those regions best placed to meet this challenge.
"High Speed Rail 2 is a key opportunity that would really benefit the North West economy as it would release capacity along the extremely busy West Coast mainline and therefore allow businesses to access new and diversified markets.
"High Speed Rail 2 would be pivotal in the process of closing the £30bn productivity gap between our region and the South East."
A briefing pack, full of supporting facts, accompanied Fender's letter.
He added: "We simply cannot afford for the significance of High Speed Rail to be lost among parochial arguments. Just as support and bold decision-making gave us the M6 and the M60, high speed rail will be fundamental to the success of the regional and national economy.
"I am writing to every council in the region: to make sure our voice is heard loud and clear and to make sure that the chance to close a £30bn gap is not lost."