Since 1942 the Grand Coulee Dam on the Columbia River in Washington has blocked adult chinook and sockeye salmon from returning from the ocean. Stephen Saks Photography / Alamy

The Columbia River Treaty, which was negotiated in the 1950s and signed in 1964, aimed to generate hydropower and protect cities like Portland, Oregon, from flooding by building five high-head hydropower dams. But they didn’t provide for fish passage, and small bands of Native people in the U.S. and Canada weren’t consulted, though they stood to lose a fishery central to their nutrition, economy, religion and culture. Some 2,300 settlers as well as Indians were flooded out of fertile valleys in Canada that now fill and empty like bathtubs by dams built to regulate downstream river flow and light distant cities.

The salmon have been absent here for 72 years — for roughly three human and 15 salmon generations. Is that long enough to seem unchangeable?

“While we’ve protected Portland from flooding, people forget we’ve permanently flooded upriver,” said D.R. Michel, executive director of the Upper Columbia United Tribes (UCUT), a coalition of Northwest tribes. Michel said the reservoirs, which can fluctuate up to 40 feet, have permanently displaced thousands of people,

“We’ve swung so far to the other side, where everything is about bottom lines and profit. It’s just a short-sighted way of looking at things,” he added.

“As a society, we really need to talk about the cost of things,” said John Sirois, a former chairman of the Colville Confederated Tribes who now works for UCUT. “Who’s really being hurt so I can have cheap power and be protected from floods?”

One might think salmon don’t have a prayer to hurdle Grand Coulee or the additional high-head dams (with no fish ladders) that were built after it.

And yet it’s been a summer of prayer up and down the river. In August alone, there were 17 interfaith vigils conducted between Astoria, Oregon, where the Columbia is nine miles wide at its mouth, to Canal Flats, British Columbia, some 1,243 river miles away in the Canadian Rockies, where it bubbles out of the ground.

A common hope expressed at the vigils was that the U.S. and Canada will modify the Columbia River Treaty by adding ecosystem-based function. This is a fancy way to say that dams should be re-engineered for salmon to pass and that water levels be managed to help with migration and to preserve the nests, known as redds, that salmon build in gravelly shallows.

The first chance either party could terminate or change the treaty is in 2024, with 10 years’ notice. That 10 years began this month, and since December, both the Bonneville Power Administration and Corps of Engineers and the British Columbia provincial government — the U.S. and Canadian entities involved — have endorsed adding ecosystem-based function. The endorsements came with a variety of caveats — mainly getting salmon past Grand Coulee Dam, which is often thought to be impossible or prohibitively expensive.

“I was a bit surprised,” said Matt Wynne, vice chairman of the Spokane Tribe and current chair of UCUT. But, he said, tribes had begun talking to the Corps of Engineers and BPA about returning salmon stocks as early as 2008.

Wynne, Michel and others say tribes are not relying solely on an opaque, decade-long process through the treaty, but also seek leverage via the federal Power Act and provisions of individual dam relicensing agreements.

When it came to the treaty, Wynne said the corps and BPA suggested the 15 river tribes in the far-flung Columbia River Basin, which reaches from the Canadian Rockies to Nevada via the tributary Snake River, first make a unified statement. It may have seemed reasonable enough, but Wynne and others knew how often the disparate tribes disagreed. To him, it seemed a cynical ploy to pin failure on the tribes.

This time, Wynne said, “The tribes said, ‘We’ve got to protect the river — we’ve got to protect the resource,’ and we came up with a common views document.”