Why Stopping Destructive Flooding Remains So Difficult on Both Sides of the Canada–U.S. Border

For residents living along the low-lying prairie straddling the Canada–U.S. border, the fear arrives long before floodwaters do.

In Sumas and Abbotsford, the sound of flood sirens has become an all-too-familiar warning—one that signals not just rising water, but the prospect of once again rebuilding homes, livelihoods, and communities.

“There’s an invisible line between us,” said Sumas resident Stacey Dailey, referring to the international border. “But you’re still our neighbours. What’s happening there is a mirror image of what’s happening here, and it’s heartbreaking.”

That shared dread resurfaced on December 10, when heavy rainfall pushed Washington State’s Nooksack River beyond its banks, triggering the second major flood in four years to affect both sides of the border.

An Existential Threat for a Small City

While flooding has battered both communities, leaders in Sumas say the stakes are especially high for their small city.

“You might be looking at the last mayor of Sumas,” said Bruce Bosch. “People don’t want to keep going through this. We need action, and we need it now.”

According to Washington State figures, the December flood damaged nearly 3,900 homes across the region, with about 440 destroyed or sustaining major damage. Bosch estimates damage within Sumas alone at between $4 million and $5 million—a staggering figure for a city of its size.

For residents like Diane Ackerman, the emotional toll is becoming unbearable.

“I don’t want to watch a river come straight toward my house again,” she said. “I just can’t do it.”

A Cross-Border Problem Without Borders

The flooding originates largely from the Nooksack River, which flows northward and spills into the low-lying Sumas Prairie, crossing the international boundary and inundating farmland and neighbourhoods in Abbotsford.

On the Canadian side, frustration has simmered for years, with some residents accusing U.S. authorities of failing to contain the river.

But Satpal Singh Sidhu, executive of Whatcom County and a former Abbotsford resident, pushed back on that narrative.

“We need to protect our citizens,” Sidhu said. “There’s been this perception that Americans don’t care, or that things were designed to send floodwater into Abbotsford. That’s not true. We care deeply.”

No Simple Engineering Fix

Despite the urgency, officials on both sides of the border agree there is no single solution.

Bosch has proposed constructing a levee at a critical point near Everson, where the Nooksack begins to overflow toward Abbotsford. However, Sidhu warns that such a barrier could simply shift flooding downstream into other U.S. communities.

“You’re not eliminating the water,” Sidhu said. “You’re just deciding who gets flooded.”

Instead, Whatcom County and Washington State officials are studying more complex options, including setting back and strengthening dikes, widening sections of the river, and restoring natural floodplains to absorb excess water.

The Washington Department of Ecology has identified dike setbacks as a priority strategy.

“By setting a dike further away from the river, you increase its capacity and reduce the chance of flooding,” said Tom Buroker, director of the department’s northwest region.

The state has committed $4 million every two years to planning work, though officials acknowledge there is no fixed timeline for construction.

Abbotsford Weighs Its Own Defences

North of the border, Abbotsford is pursuing its own set of mitigation measures, many of which depend on funding and approvals from higher levels of government.

One proposal under consideration is installing a pump on the Sumas River, which tends to swell when floodwaters cross from Washington. During severe storms, floodgates are often closed to prevent the high Fraser River from flowing back into the prairie, trapping water behind the gates. A pump could move floodwater into the Fraser even when gates are shut.

Other options include strengthening existing dikes, constructing new ones, creating temporary floodwater storage areas, and carving new floodways to redirect water during peak events.

But Ross Siemens says planning can only go so far without firm financial commitments.

“Until we have certainty around funding, it’s very challenging to design what this actually looks like,” Siemens said.

Funding Gaps and Uncertain Timelines

In November, Housing, Infrastructure and Communities Canada announced a $6 billion national fund to support local infrastructure upgrades over the next decade. However, no specific commitments have yet been made for Abbotsford or cross-border flood mitigation.

Federal officials have said further details will be released in the future, leaving local leaders uncertain about when—or if—large-scale projects can proceed.

A Shared Risk, A Shared Responsibility

Despite political boundaries, officials and residents alike agree that the flooding crisis underscores how interconnected the region truly is.

Water does not recognize borders, and solutions in one country can have consequences in another. That reality makes coordination essential—but also slow, complex, and politically fraught.

For now, communities in Abbotsford and Sumas remain stuck in a cycle of recovery and preparation, hoping that long-discussed solutions finally materialize before the next major storm arrives.

Until then, residents on both sides of the border continue to live with the same uneasy question: not if the floods will return, but when.