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COLUMBIA ESTUARY - An average of 11.6 million cubic yards of sand, silt and debris is dredged from the Columbia River between its mouth and Portland annually to maintain the current shipping channel.

That volume of material could fit comfortably in 967,325 standard dump trucks. Picture a bumper-to-bumper line from Astoria to New York City and most of the way back.

In addition to annual maintenance dredging, 14.5 million cubic yards would have to be dredged to deepen the channel to 43 feet.

"Looking at the big picture, we've recognized that regardless of channel deepening, maintenance dredging will continue to occur," said Tom Byler, water policy adviser to Oregon Gov. John Kitzhaber. "A lot of the traditional places to dispose of the materials are filling up and becoming unavailable. We're reaching a point where we need to look at other disposal opportunities."

Lower Columbia River residents are searching out creative, beneficial solutions for disposing of dredged materials. And they want government to do the same.

Rather than building underwater mountains of sand that destroy crab habitat and create dangers to navigation, they say put the sand on a beach that desperately needs it.

Rather than disposing of dredged material back in the river, where it will have to be cleared again in the future, they say pile it upland, where it can be sold as a valuable construction material.

Beach nourishment and construction are two beneficial uses for dredged materials that have captured the imagination of a diverse group of Columbia River interests this summer. More applications are in the works both locally and around the country.

To understand the value of these potential solutions, first understand something of the history of dredging on this river.

Lengthy history

Humans have lived along the Columbia River for 10,000 years. But only recently - in the late 19th and 20th centuries - have they begun to significantly alter it.

"As long as there has been a navigational use of the Columbia and Willamette rivers, there have been, to one degree or another, actions taken to improve the navigation channel," said Bill Lang, director of Portland State University's Center for Columbia River History.

The U.S. Army Corps of Engineers began improving the Columbia River channel in the late 1800s. In 1914, the Corps started a deepening project to bring the channel down to 30 feet. Since then it has deepened the channel incrementally to accommodate larger, deeper-draft vessels calling on Oregon and southwest Washington ports. The channel was deepened to 40 feet, its current depth, in the 1970s.

These projects involve scooping two main types of sediment from the Columbia River. There's fine, silty material that is carried from the great, dry plateaus and farmlands upstream from the Columbia's confluence with the Snake River. Coarse sand is scraped from the volcanic Cascades by rivers swollen with snowmelt. The Columbia carries this cargo for miles, depositing it in the navigation channel, throughout the Columbia River estuary and along the coast.

Maintaining a deeper channel takes a huge annual dredging effort. Today, Corps dredges clear about 7 million cubic yards of sand a year from the current channel and an additional 4 to 5 million cubic yards from a six-mile stretch at the river's mouth.

And it all has to go somewhere.

Good examples

Portland International Airport is built on millions of cubic yards of sand dredged from the Columbia River. Major portions of the ports of Kalama, Longview and Vancouver, Wash., rest on piles of material relieved from the shipping channel.

After Mount St. Helens erupted in 1980, rivers choked with volcanic debris were dredged and the materials used to create more land. The U.S. Gypsum manufacturing plant in Rainier sits on such material.

Some of the enormous volume the Corps dredges from the river annually has gone to land creation.

Other disposal options are not so constructive.

Dale Beasley of Ilwaco has been a crabber for more than a quarter-century. He says the mountains of sand the Corps has built up underwater at a handful of disposal sites around the mouth of the Columbia River have destroyed crab habitat at an annual cost to local fishermen of nearly $250,000 per square mile. What's worse are navigational hazards that cost the lives of two fishermen one year ago, Beasley said.

The sand mounds that the Corps hoped would wash away over time have not done so in some areas, said Doris McKillip, manager of channel maintenance at the Columbia's mouth. She noted that while the fishermen's deaths were tragic, the U.S. Coast Guard "couldn't find a relationship between our disposal activities and those deaths."

In stormy weather, piles of dredged sand can amplify waves up to 80 percent, Beasley said. That means a 12-foot wave could grow to 21 feet.

"Small (disposal) sites cause navigational safety hazards, and we've got enough death traps around the river already," Beasley said. "If you try to correct it and make it so you don't have a mound, the site gets so large that it devastates so much habitat."

The Corps is looking for other options.

A deep-water site, 4 1/2 miles out to sea from the river mouth, can handle 225 million cubic yards of dredged material over its estimated 50-year life, according to the Corps' feasibility report for the channel deepening project.

The drawback to hauling the sand out to sea is that it no longer returns to the fast-eroding beaches around the river mouth.

A popular alternative is dumping the sand on Benson Beach, just over the north jetty protecting the river mouth. In a pilot project earlier this summer, the beach received a 40,000 cubic yard sand transfusion to reverse erosion. However, this beneficial use is costly. It took about an hour per trip for dredges to dump at Benson Beach, while trips to a traditional dump site only take six minutes, McKillip said.

Beasley said the increased costs reflect the realities of keeping the Columbia River clear.

"The close, cheap sites are gone," he said. "Dumping in the future is going to be more expensive ... than it has been in the past."

Farther inland, the Corps employs a relatively cost-effective method for disposing of dredged materials. It simply dumps them back into the river.

Known as flow-lane disposal, this is one of the most common ways the Corps makes dredged materials disappear, according to its draft feasibility report for the proposed channel deepening project.

In-water disposal is usually the Corps' "least-cost alternative" for getting rid of dredged materials, but not everyone agrees with how the "least cost" is measured.

Matt Van Ess, Columbia River Estuary Study Taskforce director, said the cost of re-dredging material that has been dumped back into the river should be included in the Corps' cost estimates.

"If the least-cost alternative means you're going to have to re-dredge that sediment ... (in-water disposal) is really not the 'least cost' if you look at the full life of that sediment," he said.

Arguments against in-water disposal extend beyond calling the practice inefficient.

Peter Huhtala, Columbia Riverkeeper president, said dumping material back in the water creates clouds of sediment that negatively impact aquatic life, such as salmon, sturgeon and lamprey. A small amount of fine, silty material - which is more likely to hold pesticides, dioxins and other toxic chemicals - is disturbed by dredging.

When this material is dredged, chemicals can be released into the water and enter the food chain, eventually having an impact on bald eagles and other species that hunt in the river, he said.

A mountain of sand that otherwise would have been dumped back into the river was pumped on to Ken Leahy's large property northwest of Wauna earlier this month. Leahy plans to sell this high-quality sand for use in construction to make cement. He'll pay nearly 60 cents a yard in royalties to the Oregon Common Schools Fund.

Beneficial use alternatives such as this one are getting more attention as lower Columbia River residents highlight drawbacks to traditional disposal practices.

Byler, Kitzhaber's water policy adviser, is coordinating the formation of the Columbia Solutions Group. Made up of policy leaders from Oregon and Washington state governments, ports, environmental groups and the Corps, Columbia Solutions is trying to harness the momentum this summer's beneficial use successes have created.

"This is not a silver bullet," Byler said. "But it could help us minimize the in-water disposal issues that we face."

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