The provincial election may officially be starting next Wednesday, but the unofficial local launch of the campaign was in the foyer of Mayor Jim Watson's office on Thursday afternoon.

That's where longtime Liberal MPP and Infrastructure Minister Bob Chiarelli, joined by Ottawa–South MPP John Fraser and surrounded by city councillors, announced the province would contribute $50 million to an additional southern extension of the Trillium Line during Phase 2 of the LRT project.

​Chiarelli was at pains to point out that this was not an election promise, as we weren't in an election yet.

The $50-million provincial contribution comes from money left over from the $15 billion set aside in a 2014 fund that was expressly earmarked for transit outside the Toronto area.

That means that technically, the provincial Liberals don't have to find that $50 million in new money.

But the Trillium Line extension to bring the rail line to Limebank and Earl Armstrong roads — the site of a planned community expansion complete with retail and offices, a library and a community centre, and thousands of homes — is sure to be a key local issue in the June 7 election.

Watson has already said that he will include a question about this extension in the questionnaire that he habitually sends to party leaders in elections, demanding specific answers about their plans for Ottawa.

Leaders who give evasive answers get as much media attention as those who answer in a straightforward way.

Déjà vu for Chiarelli

Thursday's announcement was surely an odd moment for Chiarelli, to be at City Hall announcing for the second time in his career a southbound train extension into the bowels of our sprawling city.

It was Chiarelli's controversial contract with Siemens to extend the rail line south that was in large part responsible for him losing the mayoral re-election campaign in 2006 to Larry O'Brien.

O'Brien cancelled the north-south line, a move that cost the city more than $30 million.

Here we are more than 10 years later and getting light rail into Riverside South will yet again hinge on an election.

There are some notable differences in the two plans, of course.

The Trillium Line could be extended into Riverside South if the Liberals win the next provincial election. (Trevor Pritchard/CBC)

Chiarelli's original vision called for the north-south line to be converted to electric rail across the Vimy Memorial Bridge into Barrhaven, whereas the Trillium Line will continue to run diesel trains and stop short of the Rideau River.

And the city has already approved and secured funding for a southern extension of the Trillium Line to Bowesville and Earl Armstrong Roads in Phase 2 of the LRT build-out, so this week's announcement is adding to an existing expansion.

Why it might work this time

But perhaps the most important difference in the two plans is that this one might be successful.

Riverside South is a booming community, with 12,000 residents currently and a plan to grow that to 55,000 in the next 15 years or so.

Congestion in and out of the south end of the city is problematic and the traffic issues are compounded because the area is poorly served by rapid transit.

People there want more travel options.

Consider that the two developers who own the bulk of the land in the area — Urbandale and Richcraft — have agreed to levy a special charge to future homeowners in Riverside South to help pay for the project.

The special charge, which is on top of the regular development charges home builders already pay, will raise $30 million, bringing the amount available for the project to $80 million.

So a future homeowner would pay an additional $3,000 or $4,000 that would be directed to this project. And clearly, the home builders think that selling buyers on that won't be a problem.

Politics of the expansion

The proposed Trillium Line extension's end point is right in the new riding of Carleton.

Although considered by pollsters to tend Tory blue, it's a brand-new seat with no big-name candidates.

Generally speaking, it's up for grabs.

Will the Progressive Conservatives want to give up the possibility of an urban seat when it holds so few in Eastern Ontario?

PC leader Doug Ford's campaign didn't yet respond for a request for comment on the southern extension of the Trillium line, but he has already said he supports Ottawa's Phase 2 of LRT.

Four years ago, his predecessor Tim Hudak told local reporters that the province "couldn't afford" the second phase of our light-rail project.

The news went over like a rock.

It probably wasn't the only thing — or even the main thing — that lost Hudak that election, but in Ottawa, it sure didn't help.

We'll hear soon whether Ford want to take that same chance.