Columbia River Channel Improvement Project: Final Supplemental Integrated Feasibility Report and Environmental Impact Statement

The Columbia River Channel Improvements Project was originally presented in the Final Integrated Feasibility Report for Channel Improvements and Environmental Impact Statement, dated August 1999. In December 1999, Congress authorized the deepening of the Columbia and Lower Willamette Rivers Federal Navigation Channel to 43 feet Section 101b13 of the Water Resource Development Act of 1999. The authorized plan modifies the existing federal navigation project for the Columbia and Willamette Rivers and provides for construction of ecosystem restoration features. The purposes of this Final Supplemental Integrated Feasibility Report and Environmental Impact Statement Final SEIS are to document additional information, environmental analyses, and project modifications resulting from consultation of the project under Section 7 of the Endangered Species Act to update the disposal plan to update the project economics and to comply with National Environmental Policy Act NEPA requirements and with the Washington State Environmental Policy Act SEPA. Several additional ecosystem restoration features and evaluation actions are proposed for implementation to benefit the recovery of listed salmonids and other fish and wildlife resources, to avoid impacts to marine resources by ocean disposal of channel material, and to retain sand in the estuary. Creating these restoration features will use sand that would have been disposed of in the Deep Water Site. Under the revised plan, the need for ocean disposal is delayed for at least 20 years following construction. Construction volumes were updated using 2001-2002 hydrographic survey data.