Flood risk management, hydropower generation and salmon runs will suffer if the United States and Canada don’t renew a key provision of the treaty that guides how they manage the Columbia River. That key component, part of a stop-gap agreement the two countries reached late last year, expires July 31, 2027. If a new treaty doesn’t come into force by then or the two sides can’t agree on another set of interim measures, Canada will no longer have to hold back more than 1 trillion gallons of water it stores for the U.S. each spring to prevent flooding in the lower Columbia River and maximize hydropower production year-round. The two countries have been working on a new Columbia River Treaty since 2018. President Donald Trump paused negotiations earlier this month, a routine step at the beginning of a new administration, experts say. What’s not normal, they say, is the backdrop for the pause — a dramatic trade war and diplomatic clash between the two countries.

“Things that we counted on — that the United States would be a friend and ally to Canada — are now no longer true,” said Adrian Dix, British Columbia’s energy minister. Mutually profitable? The 1,243-mile-long river springs from Columbia Lake in southeastern British Columbia and flows into the Pacific Ocean near Astoria, Ore. Over the course of the 20th century dams transformed the once-wild Columbia into a machine that prevents previously inevitable seasonal flooding while also generating hundreds of millions of dollars in hydropower each year and allowing ships carrying billions of dollars in goods to travel from the ocean as far inland as Idaho. The U.S. and Canada have fine-tuned that machine since the Columbia River Treaty came into force in 1964. Under the treaty, Canada and the United States share the river’s benefits.

Canada helps regulate the flow of water through a system of dams and reservoirs, and the U.S. sends back payment for half of the extra power that can be generated from that re-timed water. In recent years, the payments ranged from roughly $100 million to $300 million each year, but that amount will decline under the 2024 interim measures. Without a new agreement, worst-case scenarios could include increased flooding along the lower Columbia River in communities like Vancouver; river and reservoir conditions that threaten salmon runs; and costly disruptions to hydropower production, farm irrigation and commercial navigation. “Either country alone could build dams and do stuff for flood control and power production and whatever else they want to do, but they could only get so much,” said Richard Paisley, director of the Global Transboundary International Waters Governance Initiative at the University of British Columbia. “But it’s only when they decided to cooperate and run together and synchronize their operations that both sides could do better.” That, in turn, he said, has generated something more valuable than any other commodity: certainty.

And certainty is the foundation of every dollar the Columbia River drives. That’s true for the $31 billion in goods shipped on the deep water channel each year; for the $3 billion in crops watered with nearly 1 trillion gallons of water in the Columbia Basin Project each year; and for the ever-growing residential, commercial and industrial power fueled by hydropower. All of those depend on the river to be managed just as it is now. They turn that relative consistency into the foundation of the region’s economy. Tens of thousands of jobs rely on the system. And it all stands to be disrupted to varying degrees. The State Department, which is leading the negotiations for the U.S., declined to answer questions. The U.S. Army Corps of Engineers and Bureau of Reclamation, which together run the Columbia River federal dam system, also declined to comment, as did the Bonneville Power Administration, which markets the power generated by the federal system. The Columbian spoke with 10 officials and experts from both sides of the border; four declined to be quoted. Diplomatic dominoes Although the two countries reached an agreement in principle late last year, Canadian officials fear the Trump administration will depart from it.

“We’ve come to an agreement. The only question is, will that agreement get caught up in the currently erratic politics of the American government?” Dix said. While Trump has singled out the Columbia River Treaty in talks with Canada, his threats to annex the country and the impact of his trade war policies on both countries’ economies are particularly worrying to Dix. Experts and officials on both sides of the border also fear negotiations won’t succeed in time. During his first term, Trump was slow to appoint key figures, and that’s shaping up to be the case again. Without those officials in place, negotiations can’t continue. If the key flood-management provision expires Aug. 1, 2027, the Columbia River would shift to a “called upon” storage regime. From 1946 until 2024, Canada assured the U.S. about 3 trillion gallons of flood risk management storage each year.

Without action, Canada would provide none. Instead, the burden of managing flood risk while trying to preserve U.S. hydropower generation capability would be shifted to the U.S. And while it’s taken for granted, the task of managing the Columbia River’s nearly 65 trillion-gallon yearly flow is not easy. That’s especially true because Canadian runoff accounts for as much as half that amount each year, and most of that comes in May, June and July. Between 15 trillion and 19 trillion gallons barrel down across the border in those months alone. To combat those flows without pre-planned Canadian storage, the U.S. will have to call on Canada to hold back water as it becomes clear it will be necessary. But that’s complicated because the two countries never agreed on the price the U.S. will pay, how drastically the U.S. will have to first disrupt its river operations and how much flood damage communities like Vancouver will have to be projected to incur before Canada will provide that called upon storage. To Barbara Cosens, a former law professor at the University of Idaho who has studied the treaty for more than 15 years, all of that leaves the U.S. vulnerable in the unlikely but possible event that these issues end up having to be settled during a year when there’s extremely heavy precipitation and risk of a serious flood.

“Those two things mean that you have to have to have good working relationships when that occurs,” she said, “and even the interim measures themselves really depend on continued good working relationships, and so that is clearly one of the wild cards we have in play now.” Impacts The potential loss of the last trillion gallons of pre-planned Canadian storage could have dramatic impacts on U.S. flood risk management, hydropower production, agricultural outputs and salmon runs. For flood control, the loss of the first 2 trillion gallons of storage earlier this year already increased flood risk along the lower Columbia in communities like Vancouver. Much of the burden of the loss of the final 1 trillion gallons would likely be shouldered by operations at the massive Grand Coulee Dam and Lake Roosevelt reservoir behind it, officials and experts say.

But that comes with consequences. If Grand Coulee is being operated more conservatively to battle floods, its operations will, by definition, be less tailored to producing power when it’s needed and prices are higher. That lack of flexibility could lower production. The Corps’ Julie Ammann, acting chief of the Columbia Basin water management division, acknowledged that in a September 2023 talk. “Changes to flow and storage project operations may have an impact on power generation,” she said. Lower levels at Lake Roosevelt also mean higher pumping costs for area irrigators during an already difficult period for them.

The potential loss of assured storage in 2027 would also affect salmon, said Joseph Bogaard of Save Our Wild Salmon. The change would increase uncertainty and, in the battle between all the competing interests looking to get their slice of the river, salmon would likely continue to come in last place. “I think it’s safe to say that salmon will continue to pay a heavy price under that sort of scenario, perhaps even heavier than it’s been under the current scenario,” Bogaard said. “There’s a lot of uncertainty.” Of course, the whole issue could be resolved if the two countries agree on another set of interim measures or manage to ratify a modernized treaty. Even barring those rosy outcomes, other factors may minimize the impacts of the potential end of assured Canadian storage in summer 2027.

Hydropower coordination between the two countries is set to continue until 2044 and that lets the U.S. know a bit about how Canada will manage the river. Corps’ models show that will lessen the impact. Cosens also noted that Canadian hydropower operations happen to sometimes align with U.S. flood control interests. “There is synergy between using those dams for flood control and using them for hydropower,” she said. Those factors, combined with the long-standing, close relationships between water managers in the two countries and the fact that former President Joe Biden kept on Trump’s lead State Department negotiator all leave Cosens hopeful.

But she fears logic alone is not enough anymore. “If you follow the logic, they should find — this Trump administration when they review the treaty — that it’s consistent with their original marching orders,” she said, pausing then adding, “whether logic applies, I don’t know.”

About the project: The Murrow News Fellowship is a state-funded journalism project managed by Washington State University. Local partners are The Columbian and The Daily News. For more information, visit news-fellowship.murrow.wsu.edu.