A small town on northwestern Ontario’s border with the U.S. is quietly preparing for a worst-case scenario. It’s one that could mean a dramatic change for the community’s water supply.

Fort Frances, home to about 7,500 people, sits where Rainy Lake empties into the Rainy River and flows north into Lake of the Woods. Fort Frances’ drinking water comes from Rainy Lake, which is bisected by the Canada-U.S. border — and vulnerable to the whims of either country’s leadership. So is the town’s economy, which relies on fishing and tourism, as well as the rhythms of a border community built around the water.

Now, tensions between the U.S. and Canada threaten those rhythms. This spring, U.S. President Donald Trump took aim at a moratorium on mining in Rainy River’s watershed, and its waters that flow past Fort Frances and numerous First Nations communities around it. Last month, tensions ratcheted up, as Trump signed an order renaming Lake Ontario to “Lake America” amid an escalating trade dispute.

The watershed that surrounds Fort Frances is called Rainy-Lake of the Woods, and it straddles both sides of the border west of Lake Superior. About 450,000 hectares of protected forest, rivers and interconnected lakes on the U.S. side is known as the Boundary Waters Canoe Area Wilderness, or colloquially, the Boundary Waters. In 2023, the Biden administration protected roughly 91,000 hectares of Superior National Forest just outside the Boundary Waters from mining for 20 years, citing the risk such development posed to the surrounding waters.

Mined copper-sulfide ore is processed to extract metals used in electrical wiring, electronics and rechargeable batteries. But when that ore is exposed to air and water, it can add sulfuric acid and heavy metals into nearby waters. When dissolved in water, that sulfuric acid breaks down into sulfate, which is toxic to wild rice, a plant central to Anishinaabe diet and culture — Minnesota has regulated sulfate in wild rice waters since 1973 for that reason. Sulfate also feeds the bacteria that convert otherwise harmless inorganic mercury into methylmercury, a neurotoxin that accumulates in fish and, through them, the people who eat them. 

But in April 2026, U.S. Congress reversed the protection for the stretch of Superior National Forest outside the Boundary Waters. The Senate voted 50 to 49 to lift the Biden administration’s moratorium that stood in the way of the Twin Metals mine, a project targeting copper, nickel and other metals, majority-owned by the Chilean mining conglomerate Antofagasta. 

President Trump signed the resolution into law in April.

In a statement to other media, Kathy Graul, director of public affairs and communications for Twin Metals Minnesota, said, “Any proposed project in this region, including Twin Metals, must undergo a yearslong, multi-agency regulatory review before earning permits to begin construction of a mine. The [Senate ruling] restores this process, and projects must prove they can meet the stringent environmental standards that have long been in place in Minnesota before moving forward.”

Back over the Canadian border, Fort Frances’ water treatment plant can handle natural fluctuations in the source water — but it wasn’t designed to handle the kind of contamination mining activity could potentially introduce, Travis Rob, the town’s manager of infrastructure and growth, told The Narwhal. Addressing that risk would mean either a costly overhaul of the plant’s treatment processes, or securing an entirely new water source, which would be “neither easy nor cheap,” Rob said. “This is what has me so concerned about the proposed mining activities.” 

He and his team have talked at length about what changes to watch for in the water that feeds the treatment plant and when the town would need to act, he said. But the stakes extend beyond Fort Frances itself. Couchiching First Nation and others also receive drinking water from the town’s treatment plant, Rob said. 

In August, Minnesota Governor Tim Walz issued a reprieve of sorts, signing an executive order directing state agencies to stop issuing leases or permits for copper, nickel and other non-iron ore mines on the U.S. side of the watershed, and to review all existing mineral leases in the area, including Twin Metals’. 

While this might hold up Twin Metals’ plans in part, the order is not immune to legal challenges from mining companies — or future actions of the Trump administration.

A smalltown mayor and First Nation’s chief seek support amid Trump’s mining push

The proposed Twin Metals mine sits at the headwaters of the Rainy-Lake of the Woods watershed.

The project has held leases in the area since the 1960s, under different owners proposing to mine copper, nickel, cobalt and platinum group metals from a deposit up to 1,300 metres below the surface, processing roughly 20,000 tons of ore a day for more than 25 years. 

According to the company, about half the waste rock, or tailings, would be stored underground; the rest would be dried out and kept above ground. Twin Metals says its processing “will remove most of the sulfide minerals,” meaning its tailings won’t result in acid drainage, and that the mine won’t discharge water used for that processing. Friends of the Boundary Waters Wilderness, an advocacy groups opposed to the project, has argued the risk  of acid drainage from the project’s tailings remains based on other mines, and exploration work in the watershed.

That same watershed carries north past Fort Frances, through Treaty 3 territory, the traditional lands of 28 Anishinaabe First Nations in northwestern Ontario and southeastern Manitoba, and eventually to Hudson Bay.

Gakijiwanong Anishinaabe Nation — formerly Lac La Croix First Nation — condemned the reversal in an April statement, according to NWONewswatch, saying neither it nor affected U.S. tribes were given the chance to testify before Congress voted.

Chief Carrie Atatise-Norwegian of Gakijiwanong Anishinaabe Nation, whose territory borders both the Boundary Waters and Quetico Provincial Park, has framed the stakes even more starkly. “This decision threatens the lives of our people, water resources and our ancestral lands,” she told CBC in April, after the U.S. Congress lifted the moratorium. “As stewards of our lands, [we] will be asserting, exercising and protecting our rights, jurisdiction and sovereignty as a nation.”

By May, Atatise-Norwegian was in Washington, D.C. In Minnesota Senator Tina Smith’s office, she signed a memorandum of understanding with the chairs of three U.S. tribal nations: Red Lake, Grand Portage and Bois Forte. They agreed to present a unified cross-border position on protecting the Boundary Waters and treaty-protected homelands, according to Red Lake Nation News. Atatise-Norwegian did not respond to The Narwhal’s request for an interview. 

The concerns of Gakijiwanong Anishinaabe Nation are shared by many Treaty 3 nations in Ontario. “This is not just a local issue, it is a transboundary concern that directly affects our waters, our environment and our way of life,” Ogichidaa (Grand Chief) Francis Kavanaugh of Grand Council Treaty 3, which represents 28 First Nations across northwestern Ontario and southeastern Manitoba, said in an April statement.

The day after the U.S. Senate voted to lift the moratorium, Fort Frances Mayor Hallikas emailed the office of Marcus Powlowski, the Liberal MP for Thunder Bay-Rainy River, urging him to speak out, and to reach out to Minnesota politicians directly. Hallikas said he also raised the issue with provincial politicians a few weeks later at the Northwestern Ontario Municipal Association’s conference in Thunder Bay, but was told it was a federal issue.

In May, the Rainy River District Municipal Association, of which Fort Frances is a member, wrote to Ontario Premier Doug Ford, aligning itself with Grand Council Treaty 3’s opposition to the mine. The letter states that sulfide-ore copper mining could cause “irreversible harm to water quality, wildlife, public health and a sustainable outdoor recreation-based economy.” It calls on “all levels of Canadian government” to engage with the U.S. and Minnesota on the issue.

“Any decision that could put [these waters] at risk is not solely a Minnesota matter,” Hallikas wrote in an email to The Narwhal. “It is an international and downstream concern that directly affects peoples in northwestern Ontario.”

He drew parallels to Grassy Narrows First Nation, where industrial mercury contamination, which can cause issues like tremors, cognitive effects and neuromuscular disorders, is one of the most consequential environmental health crises in Canadian history. 

“Northwestern Ontario understands the devastating consequences of mercury contamination,” he wrote. “That history demands vigilance, transparency and precaution.”

A binational board with no enforcement power, watching and waiting

In 1909, Canada and the U.S. signed the Boundary Waters Treaty, governing cross-border water disputes and creating the International Joint Commission to oversee exactly this kind of issue.

Merrell-Ann Phare, one of three Canadian commissioners, said the commission has no enforcement authority and no regulatory authority over water quality. Its role is to resolve disputes between nations, not enforce laws.

“We take great care to stay out of the domestic issues that are happening,” Phare said, so the commissions can preserve its neutrality for the moment a request to mediate comes in.

Only governments in Ottawa and Washington can jointly trigger that kind of review, known as a reference, under the treaty. Provinces, states and municipalities have no standing to request one directly, though Indigenous nations can be named partners.

The Ktunaxa Nation is a partner to a case in B.C.’s Elk Valley, where coal-mining pollution flows downstream into Montana and Idaho, causing unnaturally high selenium levels that have led to deformities in fish. It’s a problem the nation had raised for more than a decade before Ottawa and Washington formally asked the commission to step in, in March 2024.

That in itself is a point of concern for Johann Strube, an environmental sociologist who has studied water governance in northwestern Ontario, speaking in a personal capacity rather than as a spokesperson for Grand Council Treaty 3, where he is a natural resources policy analyst. The joint commission, he said, “was founded to advance the settler-colonial interests of Canada and the United States and explicitly excluded Indigenous nations from decision-making.”

The structure of the commission, Strube said, “still doesn’t involve Indigenous nations as nation-to-nation partners.”

Megan Garner is the Canadian co-chair of the International Rainy-Lake of the Woods Watershed Board, the regional organization that operates under the International Joint Commission.

She said the board is “aware of the termination of the mineral leasing moratorium … and is watching this issue closely.” The board is determining next steps, she said, and is committed to “balanced and representative input.” 

Garner later confirmed that, as of Aug. 19, the board “has not been in touch” with the Rainy River District Municipal Association or Gakijiwanong Anishinaabe Nation, and “has not requested input or information from any outside parties” on the mining issue, despite being aware, through its advisory groups, of a range of local perspectives.

A spokesperson for Global Affairs Canada, John Babcock, said, “Canada continues to work closely with the United States through existing bilateral mechanisms, including those established under the Boundary Waters Treaty, in support of our shared stewardship of transboundary waters.” He said they would continue to do this “as we take up the environmental challenges of the 21st century.”

Asked whether Canada had raised any new concerns with the U.S. administration specifically about the 2026 reversal, Babcock said in an emailed statement that the department continues “to monitor the ongoing developments in the region and to advocate that any increased mining activity be properly assessed and managed,” and that “the joint stewardship of the environment is a cornerstone of Canada-U.S. relations.”

Babcock did not respond to a follow-up question on whether or not Canada has requested the International Joint Commission review the issue of mine pollution leaching into the Rainy-Lake of the Woods watershed.

Canada’s caution here, Strube said, may have less to do with the technical question of jurisdiction than with the state of U.S.-Canada relations more broadly. Whether the Trump administration would feel bound by a 116-year-old water treaty, Strube said, is an open question.

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