Scoop up a handful of sand from the Columbia River’s edge and you’re holding something ancient — quartz ground from mountain granite over hundreds of millions of years, carried more than a thousand miles to this estuary. The grains are small enough to sift through your fingers in seconds.
Yet this humble material sits at the center of an escalating conflict. The Columbia’s federally maintained shipping channel moves $31 billion in cargo annually. And the Indigenous peoples whose cultures, treaty rights, and food systems have depended on this river for millennia say the sand being systematically removed is taking something far harder to measure with it.
A river built on sand — and what that means
Long before cargo ships, the Columbia’s sediment was doing quiet, essential work. Each spring, snowmelt swelled the river into its annual freshet, carrying sand, silt, and clay across a 146-mile estuary. Particles settled into marshes, sandbars, and braided channels — habitat so rich it once supported between 10 and 16 million salmon and steelhead returning from the ocean each year.
Sediment also built civilizations. Chinookan peoples developed one of North America’s densest populations along the lower Columbia, their culture inseparable from the river’s shifting landscape. Canoe design reflected every variation in the waterway: 60-foot ocean-going vessels for the powerful mouth, and 10-to-14-foot wapato-gathering boats for the shallow marshes near present-day Portland.
“The sediments and the soils are the foundation of humanity,” said Roger Amerman, a geologist, artist, elder, and citizen of the Choctaw Nation of Oklahoma who specializes in Columbia Plateau tribal histories. “Not just our culture, but all cultures.” Remove or poison that foundation, he added, and “we’re impoverished, in every kind of way.”
Engineering an imperial river: 160 years of reshaping the Columbia
The early United States viewed the Columbia’s sand differently — as an obstacle. By the 1860s, the Army Corps of Engineers had begun dredging a 107-mile shipping channel and installing what would eventually total 233 wing dams, structures designed to narrow the river and accelerate its current, scouring loose sediment from the bed.
The channel has been deepened steadily ever since. From 17 feet in 1869, it now reaches 43 feet — nearly three times the river’s natural depth — to accommodate modern cargo vessels whose hulls sometimes clear the riverbed by just 2 feet.
Federal hydropower dams compounded the damage between the 1930s and 1970s. Bonneville Dam and The Dalles Dam blocked sediment transport from upstream and severed fish migration routes. The Dalles Dam, completed in 1957, drowned Celilo Falls — one of the oldest continuously inhabited sites in North America — within a single afternoon. Tribal leaders frame each subsequent channel deepening as a continuation of colonial dispossession, the river reshaped to serve steel ships at the expense of peoples who built their entire world around it.
What disappears when the sand goes
Between 6 and 9 million cubic yards of sediment are vacuumed from the riverbed each year. Over the past century, 70 percent of the river’s marshes have been eliminated, and more than one-third of its salmon and steelhead populations are now extinct.
Dredging kills directly. Juvenile lamprey, sturgeon, crustaceans, and salmon can be sucked into dredge pipes moving sand at roughly 15 feet per second. Research on Canada’s Fraser River found approximately 26,000 juvenile salmon killed in a single day of dredging in spring 1974. Lamprey returns tell part of the story: once numbering in the millions, fewer than 20,000 now return to Bonneville Dam annually, according to the Columbia River Inter-Tribal Fish Commission.
Dredging also stirs up legacy contaminants. A 2007 study led by the National Marine Fisheries Service found that juvenile Chinook salmon from the Columbia’s mouth carried the highest PCB concentrations recorded in any Oregon or Washington estuary.
Upstream, a different crisis: sediment trapped behind the dams
Behind Bonneville and The Dalles dams, a mirror-image problem is unfolding. Cold tributaries deliver glacial sand and silt into warm, slow reservoir pools, creating shallow, sun-heated deltas that can exceed the lethal threshold of 68 degrees. Eleven years ago, hot water killed approximately 250,000 endangered adult sockeye — nearly an entire run — as they attempted to return to their Idaho spawning grounds. Tribal leaders have repeatedly asked the Corps to dredge these tributary mouths to cool the water. Those requests have gone unmet.
The result is a double bind: too much sediment accumulates behind the dams while too little reaches the estuary to rebuild the marshes and sandbars that salmon, lamprey, and sturgeon depend on downstream.
The Corps’ $578 million plan — and why tribes aren’t convinced
The Corps’ response is a 20-year, $578.7 million plan proposing to spray dredged material across thousands of acres of shallow water and shoreline in the lower river. Tribal leaders and state fish and wildlife officials are skeptical — dredged sand is coarse and nutrient-poor, and invasive species rapidly colonize disturbed ground, undermining restoration before it takes hold.
The consultation process has drawn sharp criticism. Grand Ronde council member Kathleen George said her tribe was not meaningfully included in planning. About half of the 106 proposed disposal sites have not been surveyed for cultural resources. The Chinook Indian Nation — whose unceded homelands span much of the estuary — is not consulted at all, having lost federal recognition 18 months after it was granted in 2001.
Rethinking what a river is for
In a 2024 public letter, Cowlitz Indian Tribe Chairman William B. Iyall called for a “paradigm shift” — questioning whether a 43-foot channel is ecologically or culturally viable, and proposing alternatives: reduced dredging, more freight moved by rail, ships with shallower drafts. Portland district officials acknowledged any such change would require an act of Congress.
Kathleen George put it plainly: “We are prioritizing other values on the back of our river.”
The Corps digs 210 million cubic yards of sediment from waterways nationally every year. No federal law sets a maximum channel depth, and no long-term national dredging plan exists. The Columbia’s story — a river deepened incrementally, its living foundation quietly removed, its original peoples excluded from decisions about its future — is not unique. The question it poses is whether commerce and ecology must always conflict, or whether the terms of that negotiation have simply never been fair.