Toronto is currently on the hook for at least $49 million for cancelling the Transit City light rail plan, says the head of the regional transportation agency tasked with implementing Toronto Mayor Rob Ford's new transit plan.

That outlay is likely to rise, said Bruce McQuaig, the CEO of Metrolinx. The city would have to pay for any penalties incurred for breaking or altering contracts secured in the previous Transit City plan, he confirmed.

"$49 million is what would be known at this point in time and then there would be additions based on how the discussions go with some of the suppliers," he told reporters Thursday.

Part of that figure includes the $8 to 9 million committed to planning the now cancelled Finch Avenue West light rail line, he said.

His comments come after Ford and Ontario Premier Dalton McGuinty announced a new transit plan to replace the Transit City project, which called for the installation of light rail lines all over the city.

$777M Bombardier deal will be changed

The city will now have to alter a $777-million contract with Bombardier. The city had originally ordered 185 LRT vehicles, and they now only need 130, according to Metrolinx.

But Bombardier may be interested in providing the city subway cars for Ford's proposed Sheppard subway extension, said McQuaig. That could just be added to the existing order for light rail vehicles.

"It's going to be a pretty complicated conversation," he said. "I just can't predict how much there might be of additional cost from the change in the light rail vehicle order at this point."

TTC Chair Karen Stintz was also unable to say exactly how much the city would have to pay for changing existing contracts.

So far, the city has committed $1.38 billion to Transit City-related contracts that may need to be altered or broken.

Questions around Sheppard line

Ford's plan would put Transit City's Eglinton light rail line entirely underground. There would also be a Scarborough LRT line that would replace the current RT line.

Those initiatives will come at a cost of $8.2 billion, which will come from the province.

At Ford's request, the province agreed to cancel the Sheppard Avenue light rail line in favour of a subway line, which the city will try to fund through public-private partnership and some funding from senior governments.

Ford offered few details of a possible public-private partnership.

"All the details will have to come out, but it will be built with private money," he told reporters Thursday, without elaborating.

McQuaig said it was "hard" for him to comment on the feasibility of the construction of the Sheppard line this early.

"The first step that needs to happen is that city needs to finalize its financial plan and their business case. Because fundamentally they need a decision by the TTC commission and city council to go ahead," he said.

When asked if he thought there was a business case for the subway extension given the current ridership on the Sheppard subway line, McQuaig said "the mayor has a vision of the kind of land use and development on the corridor that would build the ridership over time as well."