Hundreds of people marched through the rain in Halifax on Saturday to oppose a proposed artificial intelligence data centre in southern Cape Breton, in one of seven coordinated rallies held across Nova Scotia on the same day.

Demonstrators gathered outside Province House at noon, filling a block of Hollis Street before marching through the downtown core. The Canadian Press put the Halifax crowd at nearly 1,000 people. Rallies were also held in Kentville, Port Hawkesbury, Truro, Bridgewater, Westville and Sydney, with about 200 people in Kentville, roughly 150 in Port Hawkesbury and dozens in Truro, according to CBC News.

The protesters are calling for a moratorium on all large-scale AI data centre proposals in the province. Their target is a plan by EverWind Fuels to lease a facility at Point Tupper to Anthropic, the United States AI company behind the chatbot Claude. EverWind announced the plan last month and has described the 10-billion-dollar project as the largest private investment in provincial history.

Anthropic has signed a 20-year lease on the 18,600-square-metre facility, which it would use to power Claude. The first phase would draw 95 megawatts of electricity when it comes online in 2027, rising to 420 megawatts after a planned expansion in 2028.

Water and power sit at the centre of the dispute. Cooling water for the centre would come from Landrie Lake, which also supplies the town of Port Hawkesbury, at an average of 100,000 litres a day in the first phase and 500,000 litres a day in the next. EverWind says the system will be closed-loop, with fluid recycled or disposed of off-site rather than released into local waterways, and that it will cover the cost of all electricity infrastructure without raising customer power rates.

Speaking at the Halifax protest, Rowan Swain of the Ecology Action Centre said the province was being promised a future in which corporate profits came first. “Nova Scotians deserve better than this,” he said. “There are options for this province that can grow our economy without sacrificing the health of our communities and our environment and our fresh water.”

In Kentville, protester Sadie Beaton raised concerns that Mi’kmaw consent had not been given, and said she was demonstrating to ensure the responsibilities of the Peace and Friendship Treaties were upheld. In Port Hawkesbury, organiser Benjamin Lauzon called on Premier Tim Houston to convene an emergency session of the legislature so the project could be debated openly. “The MLAs have a duty to bring the public’s concerns to the legislative assembly,” he said. “Right now, it’s not a decision for him alone to make.”

EverWind says it intends to draw electricity from the provincial grid until onshore wind turbines are built. It holds approvals for the wind farms but has not yet started construction. The company’s director of engagement, Mark Stewart, said earlier this week that measures must be in place to develop the project responsibly and in line with federal guidelines and provincial expectations. EverWind did not respond to a request for comment about the protest.

The province said in a statement that it accepts and expects Nova Scotians to have questions about the data centre, and that the potential for a 10-billion-dollar investment was something to be open-minded about. “Our government has been clear that a data centre can only proceed if they can meet and exceed provincial and federal guidelines, which include protecting water, the environment, and power rates and capacity,” it said. Environment Minister Timothy Halman has said the project requires industrial approval rather than an environmental impact assessment.

A petition on Change.org against AI data centres in the province has collected nearly 28,000 signatures. Organisers say the seven rallies were only the start of a campaign to force a pause on large-scale data centre approvals until the province sets clear rules on water, power and environmental review.