Columbia River Channel Project, Port of Portland Channel Project Pamphlet

According to the Port of Portland, dredging three more feet in the Columbia River would not adversely affect the environment. Deepening the Columbia River channel would allow larger ships to travel further upriver, expanding international trade relations. Many people feel the dredging is unnecessary and environmentally harmful. Dredging may stir up toxic substances such as PCBs and dioxins found in Lower Columbia River sediments, shorelines may erode, and large ships may leak toxic substances into harbors.