Idaho Rivers United v. United States Army Corps of Engineers

The federal district court for the Western District of Washington granted summary judgment to the United States Corps of Engineers in a case in which environmental and conservation groups alleged that the Corps’ plan for maintaining the Snake River navigation channel violated the National Environmental Policy Act (NEPA) and the Clean Water Act. The court rejected the plaintiffs’ argument that the Corps had violated NEPA by failing to incorporate the impacts of climate change on sediment deposition in its decision-making. The court said that “[p]laintiffs’ climate change argument boils down to an assertion that the Corps should have forecasted future climate change sediment yields …, despite the speculation inherent in such an exercise,” and that NEPA did not require consideration of speculative information.