Environmental advocates and First Nation members opposed to the expansion of the Kinder Morgan Trans Mountain Pipeline concluded a four-day long march from Victoria to Burnaby Sunday.

The Walk 4 the Salish Sea is the beginning of what organizers say will be a summer of escalating opposition to the pipeline expansion.

“This coast is precious to all of us. It’s the basis not only of First Nations culture and livelihood but important local economies,” Bobby Arbess, lead organizer of the walk, told CTV Vancouver.

“I don’t think anyone here on the coast wants to see this increased risk of an oil spill on our local waters.”

The proposed Kinder Morgan pipeline expansion will twin the existing pipeline that transports bitumen from Alberta’s oil sands to port in Burnaby, B.C to be exported to Asia. The expansion will triple pipeline’s carrying capacity from 300,000 barrels a day to 890,000.

That also means more tankers carrying it will pass through waters surrounding Victoria and the Burrard Inlet in Vancouver, an area sometimes called the Salish Sea. There is strong opposition to the pipeline in those areas because residents perceive the risk of an oil spill on the coastal environment to be too great.

“Clean water and clean land matter more than money,” Audrey Seigl, an organizer and member of the Musqueam Nation, said. “If we continue to allow the water and the land to be destroyed, we literally have nothing left to maintain our own lives.”

Federal Green Party Leader Elizabeth May also participated in the walk. She’s confident that strong opposition from First Nations and a series of legal challenges will prevent the pipeline from being built.

“We have very strong court cases…The City of Vancouver, the City of Burnaby, the Tsleil-Waututh and the Musqueam,” she said. “This is just the beginning. This pipeline will not, ever, be built.”

The Texas-based oil company, however, has said construction on the $7.4 billion project will begin in September, provided it can secure necessary financing through an IPO that closes May 31.

The federal government’s National Energy Board gave the project a green light provided it met certain conditions last May, and the B.C. provincial government granted environmental assessment approval in January.

Christy Clark’s Liberals also negotiated a 20-year revenue-sharing agreement worth about $1 billion with Kinder Morgan before the provincial election.

But for marchers, those government approvals don’t mean anything without consent from First Nations.

“First and foremost, it’s not up to the government to decide what happens on my ancestors’ land,” Seigl said

With files from CTV's Breanna Karstens-Smith.