Opinion ID: 3038513
Heading Depth: 5
Heading Rank: 2

Heading: Potential Direct Sediment Loss from the

Text: Channel Deepening Project Similarly, the 2003 FSEIS took a hard look at the effects of removing sediment from channel deepening, and concluded that such practice would not diminish sediment availability in the littoral cell. Further undermining NWEA’s concerns, between the 1999 Final Integrated Feasibility Report and Environmental Impact Statement and the 2003 FSEIS, the Corps altered the proposed project, reducing both the volume of proposed dredging as well as the amount of material from channel deepening slated for ocean disposal. As reflected in the 2003 FSEIS, the Corps concluded that, as altered, the channel deepening project simply would not remove enough sediment to make an environmental difference. Construction and 20 years of maintenance of the proposed 43-foot navigation channel would remove an estimated 70 mcy of sand from the Columbia River and place it in upland disposal sites. Approximately 40 mcy of dredged sand would be disposed of back along the navigation channel or in ecosystem restoration sites in the estuary. Critically, the analysis reveals that the volume of sand removed by dredging would not reduce the available sand supply in the riverbed. The FSEIS concludes: [T]he removal of sand from the river will not alter sediment transport to the estuary (Exhibit J). The volume to be dredged over the life of the project is only a tiny fraction of the total volume of sand in the riverbed. In addition, transport potential, rather than sand supply, is the limiting factor in sediment supply to the estuary. 10088 NORTHWEST ENVIRONMENTAL ADVOCATES v. NMFS SER 295. Ultimately, by considering the disposal of material dredged from both the MCR and the navigation channel, the Corps took a hard look at the effects of directly removing sediment from the littoral cell through operation of the channel deepening project.