Lower Mainland mayors are hopeful as they wait for the announcement in Wednesday's federal budget that they believe will be the domino that sets off a massive transit expansion here.

"We are cautiously optimistic that we'll get a substantial amount," said New Westminster Mayor Jonathan Coté, who heads a subcommittee on the TransLink mayors' council focused on funding strategies. "It will probably be one of the most substantial ever from a federal government."

Mr. Coté said indications that officials at TransLink – the transportation agency for the Lower Mainland – have had from discussions with the government is that the region will likely get somewhere between $2-billion and $3-billion, counting the money that was already given in a first phase of funding last year. The new money would be from a total transit package of about $16-billion for the country.

Story continues below advertisement

The mayors' 10-year plan for transit expansion had pegged the total bill at $7.5-billion for an extension of the Broadway subway, a new light-rail transit line in Surrey connecting the central city with Guildford and Langley, a new Pattullo Bridge, an additional SeaBus, and numerous additions to bus service.

The New Westminster mayor said it also appears likely that the federal money will cover 40 per cent of capital costs in the plan.

That is less than the 50 per cent that Prime Minister Justin Trudeau announced as the federal government's share of first-phase funding, but more than the one-third that Ottawa has typically committed in the past.

Mr. Coté said the federal dollars will open the door for the provincial parties, who are facing a May election, to declare what their potential governments would contribute.

So far, the ruling BC Liberals have said they won't make a firm commitment, beyond 33 per cent for major capital projects, until they see what the federal government is proposing.

The provincial NDP has said it would cover 40 per cent of all costs in the mayors' plan, both capital and operating.

Green Party MLA Andrew Weaver has said his party sees a one-third commitment to major capital projects as a starting point, but wants to see what the federal contribution is before saying anything more.

Story continues below advertisement

But Mr. Coté said he's hopeful that, once real federal dollars are on the table, the province will jump in to take advantage of that. The same is true for the local mayors, who have sometimes balked at coming up with tax increases to pay for a regional share.

"I don't think either wants to let this slide."

But transit money isn't the only thing people in B.C. will be watching.

The Trudeau campaign in 2015 had also promised a big jump in spending for affordable housing.

The executive director of the B.C. Non-Profit Housing Association believes that will be coming, too. Kishone Roy said early signs show that the budget will likely commit to $12-billion in housing spending over the next decade.

However, he hopes that B.C. will get more than its usual share, based on proportion of the population.

Story continues below advertisement

"The crisis in B.C. is worse than in the rest of the country. So we've asked that B.C.'s portion of the funding account for that in some way."

B.C. now accounts for about 13 per cent of Canada's total population. But Mr. Roy said he and others who work in the affordable housing and rental sectors think that B.C. should get about 18 per cent of the allocation.

The province is suffering from a huge backlog in affordable housing because its population grew much more than that of other provinces, its economy has been hot, and housing prices have risen much faster than elsewhere.

"If it's delivered strictly on the basis of population, sending $100,000 to PEI and $100,000 to B.C. isn't fair," Mr. Roy said.