Marsh v. Oregon Natural Resources Council
Headline: Elk Creek dam ruling lets construction continue by reversing the appeals court and upholding the federal agency’s decision not to require a second environmental study, easing near-term progress on the project.
Holding: The Court held that a judge should overturn the agency’s decision not to prepare a supplemental environmental study only if the decision was arbitrary or without reasonable basis, and it found the agency’s choice reasonable here.
- Allows Elk Creek dam construction to continue without another federal study.
- Makes courts defer to agency technical judgments on new scientific information.
- Requires agencies to take a hard look but not to supplement for every new report.
Summary
Background
Four Oregon conservation and fishing groups sued to stop construction of a large dam on Elk Creek in the Rogue River Basin, arguing the federal builders had not fully studied cumulative impacts, had omitted a "worst case" analysis, and should prepare a new study after new scientific reports surfaced. The Corps of Engineers completed an Environmental Impact Statement in 1980, began construction after later funding, and the dam is now partly built; the challengers pointed to a February 1985 memorandum from state fish scientists and a 1982 soil survey as new information.
Reasoning
The central question was whether that newly produced information required a supplemental environmental study before construction could continue. The Court explained that agencies must prepare supplements when significant new information would affect the still-pending parts of a project, but courts should defer to agency expertise and overturn such agency decisions only if they are arbitrary or without reasonable basis. Here the Corps carefully reviewed the new documents, hired independent experts, and issued a Supplemental Information Report explaining why the new reports did not show significant, reliable new impacts.
Real world impact
Because the Court found the Corps’ review reasonable, construction may continue without another federal study for now, affecting local fishing, wildlife habitat, and project schedules. The ruling also clarifies that judges should give weight to technical agency judgments when experts dispute scientific data, while still requiring agencies to take a ‘‘hard look’’ at new evidence.
Dissents or concurrances
At the appeals level one judge dissented, arguing the Corps’ judgments were reasonable and did not require another study; the Supreme Court agreed with that view.
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