The National Energy Board started hearing deputations from the public today about Enbridge's proposal to increase the capacity of oil in its Line 9 pipeline that runs through Toronto.

Line 9 has been running the same course between southern Ontario and Montreal, including north of Toronto, for about four decades, but the controversial plan to reverse the flow and increase capacity has brought new attention to the pipeline.

Lawyers for several Ontario First Nations told the board this morning that the proposal should not go ahead without direct consultations with the communities they represent.

The CBC's Genevieve Tomney said First Nations are concerned about the potential environmental impact an oil spill would have on their land.

A map shows the pipeline route through north Toronto. (NEB)

The oil company wants to increase the amount of oil it can run along the line from 240,000 barrels a day to 300,000. It also wants to reverse the flow — which currently runs east to west — to west to east in order to potentially transport bitumen from Alberta's oilsands.

The City of Toronto is expected to submit its deputations on Wednesday afternoon.

Silent protests

Several silent protesters showed up to Wednesday's hearings, which continues through to Saturday at the Metro Toronto Convention Centre, but quickly left after showing their muted opposition.

The board is a federal agency that will decide on whether the proposal can become a reality.

Despite Enbridge’s assurances, environmentalists and other concerned residents along the 639-kilometre stretch of the line suggest that the modified Line 9 would put multiple communities at risk.

Many worry that the plans to run a heavier — and what they claim to be harsher — form of oil will put too much pressure on the aging pipeline and increase the risks of leaks.

"Tarsands oil is much more dangerous to ship, it's much more dangerous if it spills,” said Adam Scott of Environmental Defence, pointing to a 2010 leak in Michigan as an example of what could happen.

“It spilled three million litres of tarsands oil into the Kalamazoo River and devastated the community nearby,” Scott said.

That incident is the largest on-land spill in the history of the U.S. and has already cost Enbridge more than $1 billion.

Graphic designer and accidental activist Gerry Dunn has been trying to stop the plans by trying to educate the public about the ins and outs of the line and proposal.

Dunn said what many do not know is that Line 9 now runs from Montreal to Sarnia, crossing rivers that lead to Lake Ontario and also runs through north Toronto. Many have said a leak could taint the drinking water supply of millions.

“Everybody has a stake in this issue and we need to get this talked about,” he said.

No affect on safety, Enbridge says

But the Alberta-based company says there's a lot of misinformation being being put out.

"It's been a hard thing to really get our story out in an independent way," Dave Lawson, Enbridge's vice-president of major projects, told The Canadian Press.

"The environmental groups … it's difficult for them to target the oilsands, but if they slow down the pipeline or stop the pipeline from moving that oil, that's shutting in the oilsands crude. We've seen a lot of that."

Enbridge argues that the change to Line 9 will not affect safety.

“We can prove that we can transport this product safely,” said Graham White with Enbridge.

The company will have to prove it to the National Energy Board in order to see its plan come to fruition.