Alberta Premier Rachel Notley has pledged $1.53 billion toward Calgary's Green Line LRT project, which she calls "the most ambitious LRT project in Calgary's history."

The Green Line would be a massive public transit line that would stretch 46 kilometres across 28 stations from 16th Avenue North to Seton in the city's southeast.

"This is really a big day for Calgary," Notley said Wednesday in downtown Calgary.

She presented the funding with Mayor Naheed Nenshi and Finance Minister Joe Ceci at 10th Avenue and Macleod Trail S.E., where work is being done to prepare for Green Line construction.

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The Green Line is being built in stages. This first segment, expected to begin in 2020, was previously promised

The federal government previously committed $1.53 billion to this first stage, which runs from 16th Avenue North to 126th Avenue S.E. Work is expected to begin in early 2020.

On Wednesday, the province signed an agreement with the City of Calgary that secures both promised investments, Notley said.

The first segment is scheduled to open in 2026, and is expected to cost $4.65 billion for capital construction, according to the city's website.

Environment, community, jobs

The funding comes through Alberta's Climate Leadership Plan, she said. Revenue from the carbon levy is being used through that plan to fund projects that reduce greenhouse gas emissions.

This project will improve transit services, which will in turn put more people on trains instead of cars, Notley said.

"The Green Line is the biggest transit project in the history of Calgary. It will transform the way Calgarians move around the city. It will generate enormous social and economic benefits for generations to come," Notley said.

"It's good for the economy, it's good for the community, it's great for the environment and it is great for everyone in Calgary."

She also estimated the construction would generate thousands of jobs and spark private development along the line.

Premier Rachel Notley says the Green Line agreement will secure the federal funding, as well. (Monty Kruger/CBC)

Nenshi said the Green Line, when complete, will double Calgary's current light-rail network and move more than 60,000 people daily.

"Now that this agreement is signed, it means we can move forward," the mayor said.

"We can push forward on getting this project out to market, we can push forward on creating 20,000 direct and indirect jobs in Calgary — something that's absolutely critical in terms of economic stimulus."

In a tweet after the funding announcement, United Conservative Party Leader Jason Kenney expressed his support for the project and suggested it would go ahead under a conservative government.

Just now, <a href="https://twitter.com/nenshi?ref_src=twsrc%5Etfw">@nenshi</a> on the Calgary Green Line: "This project is getting built." <br><br>Agreed! —@jkenney

In the past, he has questioned the source of funding for the Climate Leadership projects.

"I reject the premise that the carbon tax is funding those projects," Kenney recently told CBC.

"That is just a political accounting gimmick. There is one general revenue fund for the Province of Alberta that all revenues go into, including carbon tax revenues."

Mayor Naheed Nenshi and Premier Rachel Notley announced the province will give $1.53 billion to the first segment of the Green Line, bringing outside funding to $3 billion in total. (Monty Kruger/CBC)

He promised to cut the tax if elected in this year's provincial election. Notley, in turn, said that if the carbon levy were cancelled, the Green Line would be cancelled.

According to the province's fixed-date election legislation, the next election must be held sometime between March 1 and May 31, 2019.

At the Green Line announcement, Notley said contract language can be tightened to secure funding, should there be a change in government.

However, she said that if Kenney were elected and wanted to change the funding, he could by passing legislation.

"If they cancel the Climate Leadership Plan … the many, many programs that are funded out of it will disappear," Notley said, before gesturing to the nearby transit construction.

"And what we will end up with is a hole in this part of Calgary as a testament to that kind of 'forward-thinking.'"

'Train has left the station'

Nenshi noted preparatory construction had already begun and the procurement process would get underway immediately.

"This project's getting built. There are holes in the ground, there will be more holes in the ground," Nenshi told reporters.

"So of course the legislature could do anything. They could dissolve the City of Calgary tomorrow if they really wanted to.… But in reality, this train has left the station."