Protesters from the Tsleil Waututh and Squamish First Nations travelled along a ceremonial route from Ambleside Park, just west of Lions Gate Bridge, before heading through Burrard Inlet and then east towards Cates Park in Deep Cove.
Others from Vancouver Island and Washington were expected to join the paddle, which culminated with both First Nations signing a joint declaration against the pipeline project to deliver oil to tankers on B.C.'s coast.
Leah George-Wilson, a former chief of the Tsleil Waututh First Nation, said her band is concerned about increased tanker traffic.
"Not just tanker traffic, but super tankers. They'll be doubling those numbers as well. It isn't a potential of a spill, it's when a spill will happen, we've already seen spills," she said.
"Our old people have said, 'When the tide goes out, the table is set' but that currently isn't the case any longer," she added, talking about food sources on the coast. "We can eat the crabs from the beaches but we can't eat the clams or the mussels. There are fish that still go through but our inlet has been heavily impacted."
Kinder Morgan has said it wants to twin its existing Trans Mountain Pipeline that carries various oil products from Alberta to the Westridge Marine Terminal in Burnaby, where they are loaded onto tankers in Vancouver Harbour.
The proposed $5-billion expansion project would increase the 1,150-kilometre pipeline's capacity from 300,000 barrels per day to 850,000 barrels per day, requiring an increase in the size and number of tankers passing through Vancouver Harbour.
That prospect has mobilized opponents concerned about the increased possibility of environmental disaster from an oil spill on land or in the sea.
In July, more than 300 people packed a community hall in B.C. Premier Christy Clark's Vancouver Point Grey riding to voice their concerns over the proposed pipeline expansion.