Columbia and Willamette Channel Deepening Project, cont.

Channel Deepening, Toxics & Water Quality

Water Quality & Channel Deepening
Testing for Contaminants
Effect of Toxic Chemicals on Columbia River Species

Water Quality & Channel Deepening

THIS SECTION UNDER CONSTRUCTION

Testing for Contaminants

Toxic contaminants from industry, commercial ship traffic, agriculture, and other human-caused sources have accumulated in the Willamette and Columbia Rivers. In fact, so much contamination is present in Willamette River sediments that a 6-mile portion of the river is currently being designated as a Superfund site. Disturbance or disposal of contaminated dredged materials could result in biomagnification of contaminants through the food chain. When the channel is dredged, the sides collapse over time into the deep cut. This "side sloughing" can release or reveal contaminants from the shallower waters on either side of the navigation channel, where toxic particles often accumulate. Worse, in order for individual ports to benefit from the project, they must deepen their private access channels and ship berths. These areas are known to have higher concentrations of toxins than sediments in other parts of the river. These related projects were not taken into account by the Corps' review of the project's environmental impacts.

Despite the concern about the level of contamination and its effects on wildlife of the Lower Columbia River estuary, only limited testing has been done to evaluate the potential damage this project could cause. Of the 90 samples taken by the Corps, only 23 were tested for chemical contaminants during the preparation of the Environmental Impact Statement for this project. The Corps only sampled sediment to a depth of 10 inches, though it will dredge as deep as 5 feet. The screening levels used by the Corps to evaluate materials proposed for dredging and flowlane disposal are not protective of fish and wildlife in the lower Willamette and Columbia Rivers.

The Corps asserts again and again that the sediment in the Columbia navigation channel is clear and clean for open water disposal, in large part because the sand is so coarse. However, in dredging to 48 feet -- 43' plus five feet advance maintenance dredging (AMD) -- the Corps will encounter fine clays and other fine sediments that have never been uncovered. Even though these may be clean, dissolved contaminants in the water column can adhere to those fine particles when they become resuspended during dredging activities. Destined for the estuary, the sediments will become the new surface layer of the estuary floor.

Effect of Toxic Chemicals on Columbia River Species

THIS SECTION UNDER CONSTRUCTION

"[A]ctions… as a result of channel deepening could cause increased dredging activity near ports, marinas, or harbors in areas containing fine-grained or contaminated sediment. . . .It is predicted that all bald eagle pairs that occur on the Columbia River below the Portland-Vancouver area (29 pairs) will be harmed as a result of biomagnification of contaminants mobilized during the dredging of fine sediments in or around the Columbia River channel." -- U.S. Fish and Wildlife Service Biological Opinion, December 6, 1999

News/Media | Action Alerts | Programs | About Us | Getting Involved
Resources | Contact Us | Kids Page | Northwest Places | Home

133 SW 2^nd Ave., Portland, OR 97204-3526 (503) 295-0490 FAX 295-6634