The Columbia River begins in the Rocky Mountains of southeastern British Columbia, then flows north before making a sharp turn south to the U.S. and finally west to the ocean. It is the fourth largest river in North America by discharge. Only the Mackenzie, the St. Lawrence and the mighty Mississippi are larger. Like rivers around the world that curve and snake across the straight lines of political borders, any industrial use of the Columbia had to be negotiated by the two countries it flowed through.

On a rainy day in September 1964, leaders, including Prime Minister Lester Pearson and President Lyndon Johnson, met at the Peace Arch between Surrey, B.C., and Blaine, Wash., to ratify the CRT. The two leaders extolled the treaty’s benefits — hydroelectricity, the revenue generated — and what it meant for bilateral relations. “It is another illustration of friendship … and the way two countries can and should work together,” said Pearson. Johnson described the success of the Canada-U.S. relationship as depending on four pillars — peace, freedom, respect and cooperation — that could serve as a model to other nations.

If hydropower is what we often hear about the Columbia River Treaty, it’s flood prevention that is usually cited as its initial justification. Before the treaty dams, flooding along the river was a seasonal problem and occasionally brought devastation to low-lying communities. One of the worst floods occurred on May 30, 1948, when the Columbia burst through a dike and decimated Vanport, Ore., the second largest city in the state. A reporter for the Portland Oregonian described waves of water surging into the city like ocean breakers, some six feet high. Residents used rafts and rowboats to rescue those trapped. In the end, 18,000 people were left homeless, at least 15 people lost their lives, and the damages were over $100 million. The destruction was felt not only in Oregon but also along the Columbia River in Washington state and B.C. It was the “Worst Disaster in 54 Years,” blared a New York Times headline at the time.

The Columbia River Treaty really contemplated two things — flood control and hydroelectricity. And in this respect, it accomplished a great deal, preventing billions of dollars in property damage, and creating billions more in B.C. revenue through hydroelectricity — both generated in B.C. and the share the province received from the United States. According to the authors Robert Sandford, Deborah Harford and Jon O’Riordan in their book, The Columbia River Treaty: A Primer, in terms of its narrowly stated goals the Columbia River Treaty was “an enormous success.”

But while its utilitarian aims benefited many, the treaty also left a trail of damage and pain that, under renewed negotiations, was being addressed, even though its past still largely remains unknown to many in B.C. and across the country.

South of Revelstoke, the Columbia calms and broadens into an expanse of water known as Upper Arrow Lake. It’s surrounded by green mountains with clearcut areas that look like patchy sheep in mid-shear, and on a warm summer day its sandy shore is a magnet for locals. Teenagers perch on logs, sipping drinks and listening to music; a group of young boys excavates sand with mini dump trucks; and a couple poses for a selfie at the tip of a rocky point. But beneath the lake’s wind-dappled surface lies evidence of a troubling history.

In 1968, when the Hugh Keenleyside Dam was built upstream from Castlegar, B.C., it raised water levels in the Upper and Lower Arrow lakes by 12 metres, submerging more than 10,000 hectares of arable land. Farming families surrendered their life’s work, and many watched as their houses were burnt to ashes by the public utility, BC Hydro, a practice required to clear the land before the flooding. Photos archived by the Arrow Lakes Historical Society show wooden houses wrapped in flames in the towns of Renata, Edgewood and Twelve Mile.

Any collective plan to bring the salmon back must rectify past prejudices; for instance, when the Columbia River Treaty was negotiated in the 1960s, First Nations were not consulted. “We were given no consideration whatsoever,” Teneese explains, adding that “it was like we didn’t even exist.” In 2018, when the federal government began to renegotiate the treaty with the U.S., it left the Syilx, Ktunaxa and Secwépemc out of the talks. The sense of betrayal, especially given the historical context, was palpable. Grand Chief Stewart Phillip, then chair of the Syilx Okanagan Nation, described it as “shocking” and an “act of absolute treachery.” In the end, their anger was heard: they were included as observers to the treaty negotiations, a first in Canadian history. As Grand Chief Phillip put it, this was “courageous” and would help “ensure any new treaty addresses the mistakes of the past.”

The agreement in principle, reached after 19 rounds of negotiations, includes cash payments to B.C. of almost $38 million a year for storing water to prevent floods in the U.S. and an additional $17 million a year for other benefits the U.S. gets from controlled waters, like navigation, recreation and irrigation. The Canadian entitlement — the share of extra power B.C. gets from U.S. dams and then sells for a profit — would shrink, dropping by nearly 40 per cent of its former level in the first year, as the Americans are now less reliant on power from Canadian dams. B.C. makes a lot of money from the Canadian entitlement: between $100 million and 300 million a year. So the reduction would sting, but overall, B.C. would gain much more control over how it operates its section of the Columbia River.

That dream would have been greatly helped by the agreement in principle. But then, a new Trump presidency dawned. On a 2025 call with former prime minister Justin Trudeau, Trump questioned the validity of a 1908 treaty that demarcated the international border. His commerce secretary, Howard Lutnick, followed up with a call to Dominic LeBlanc, Canada’s minister of international trade, in which Lutnick reportedly relayed that the U.S. wanted to blow up more agreements — such as those governing the Great Lakes and other water-sharing conventions. Trump is a dangerous and unpredictable figure, and his fluctuating tariffs bear this out, so his fusillade of threats can’t be taken as idle. Yet looking at the Columbia River Treaty and how it’s structured offers some perspective on how to approach this volatile neighbour.

In a virtual information session about the Columbia River Treaty hosted last year, B.C.’s energy minister, Adrian Dix, took the long view. First, he said, it’s not unusual for a new U.S. administration to review current international engagements. Second, the Columbia negotiations were not formally suspended but rather paused. What’s different about this administration, he acknowledged, are the president’s threats to Canada’s sovereignty and economy, which should be taken seriously. It’s possible that the U.S. (or even Canada) could unilaterally terminate the treaty, he said. But even then, under the binding terms of the treaty, this wouldn’t take effect for another 10 years, at which point the Americans would have held their 2028 and 2032 presidential elections. An unsaid implication: much can change in 10 years. “There is a lot of noise,” Dix said, adding that the long-term signal had both countries working together for mutual benefit.

At the time of writing, the negotiations are still paused; regardless, the work to bring the salmon home forges on.