Municipal, provincial and federal politicians officially broke ground for the $2.6-billion project to extend the Spadina leg of the TTC’s 1 Yonge - University - Spadina subway to Vaughan yesterday.

The groundbreaking ceremony, in a field beside Downsview Station, officially marks the start of work on the first phase of the project. In the first phase, contractors will build a new link between the Wilson subway yards and the extended line, so that trains on the northern end of the line can operate to and from the yards.

All three levels of government are sharing the $2.6-billion cost of extending the subway northwest from Downsview to York University and the Vaughan Corporate Centre.

The federal government has contributed $679 million — $5.5 million to connect the Wilson yards with the subway. Ontario is funding $870 million of the project. The City of Toronto and the Region of York together are paying for a third of the project — $526 million from the City and $352 million from the Region.

According to the National Post, Toronto Mayor David Miller thinks the next subway expansion should come with the “downtown relief line”, instead of extending the Yonge leg of the subway to Richmond Hill.

(”If the core doesn’t work, the region doesn’t work,” the Mayor said. The proposed downtown relief line would connect downtown Toronto with stations on the eastern and western parts of the 2 Bloor - Danforth subway.)