My first political epiphany concerned the world trade protests in 1999. I was 17 and had a feeling globalisation was a good thing – until I realised it was about money and economics, not people and culture; so in the early 2000s I joined some anti-globalisation protests in Quebec.

Several years later, I heard about kayaktivism. I’d kayaked before, and been an activist, but never married the two. My first kayak protest was in Quebec’s Saint Lawrence estuary in 2014. TransCanada wanted to build a supertanker port in a beluga whale nursery. Our mission was to kayak to a boat doing seismic testing, unfurl a banner and take a picture. It wasn’t about stopping the boat, but drawing attention to what was happening.

Later that year, though, a group of Pacific islanders took to canoes to block coal ships in Newcastle, Australia, to protest against coal’s impact on climate change; they’d seen coastal erosion and a rise in sea level on their islands. It was largely successful: they were moved on, but delayed a bulk carrier and got a lot of press. That’s when I realised that water-based action could be a great way to protest injustice. I’m now part of a collective of kayaktivists in Vancouver called the Sea Wolves.

There’s excitement when you’re getting ready to paddle across the water, but also nervousness; there’s a confrontation looming and you don’t know how it’s going to go. That day, it went smoothly and we got some powerful images, which were picked up by the Canadian press.

My most recent protest, on 28 October, was much more risky than the first. We weren’t just raising a banner: our plan was to disrupt a pipeline extension in the port of Vancouver. We wanted to use kayaks and canoes to create a “wall of resistance” against the operator, Kinder Morgan, and show the banks financing the project that there are risks associated with this kind of investment. The extension would mean a tripling of the production of tar-sands oil, one of the most C0 2 -intensive fuels on the planet. There were at least 60 people on the water and I was near the front.

Kayaktivism can be dangerous: we get close to moving supertankers. It’s like David and Goliath. Then there’s the worry about how private security will react. Security companies are not held as accountable as police, and there was even nervousness about how the police would respond. We had medics on the water, in case anyone got tired or injured, and a couple of motorboats for safety.

I hoped everyone would keep a level head. Before we paddled off, we were welcomed on to Tsleil-waututh First Nation territory, and there was a briefing where we acknowledged we might be putting ourselves in an arrestable position. In the water, everyone grouped together before crossing the bay.

As we approached the construction barge, we noticed they had placed buoys in a circle around it. Someone in a Kinder Morgan security boat kept shouting, “You’re moving to a construction zone. This is private property.” The voice was becoming more irate, creating tension. We noticed police watching, but we ignored the warning and carried on. I was live-streaming the protest for Greenpeace as the kayaktivists made their way to the barge and circled it. All work on board stopped and the kayaks stayed where they were.

After about six hours on the water, I started paddling back to shore. But the police intervened with some of the kayakers who remained close to the barge. They pulled each kayaker, with their kayak, on to a police boat and charged them with criminal mischief. But we were able to disrupt Kinder Morgan’s work that day and send the message that people would stand against this project.

This is just the beginning of on-the-water resistance. The days can be long, and there’s a lot of setting up and tearing down gear, battling the elements. It’s exhausting, but incredibly rewarding. There’s something profound about being on the frontline. You have a real link to what you’re trying to protect. On the water, you look at the coastline and the mountains, you see seals and bald eagles, crabs and starfish: everything we know is being put at risk.

• As told to Alex Hannaford.

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