## Facts

- Idaho sportsmen and environmental organizations sued the Secretary of the Interior and the Bureau of Reclamation over operation of Palisades Dam and Reservoir on the South Fork of the Snake River, part of the congressionally authorized Minidoka Irrigation Project.
- The Bureau had managed Palisades continuously since completion in 1956 and coordinated its operations within a larger system of Snake River storage and delivery facilities.
- The South Fork of the Snake River supports a prominent trout fishery, and plaintiffs alleged that low releases from Palisades harmed habitat and spawning conditions downstream.
- The Bureau generally maintained releases above roughly 1,000 cubic feet per second (cfs) but periodically reduced flows below 1,000 cfs during dry conditions to preserve reservoir storage for irrigation deliveries and contractual obligations.
- Plaintiffs sought declaratory and injunctive relief, asserting NEPA required an environmental impact statement (EIS) before the Bureau reduced flows below a specified minimum (ultimately 1,000 cfs).
- After an extensive evidentiary hearing, the parties submitted the case on the merits on the hearing record; the district court entered judgment for the Bureau, and plaintiffs appealed.

## Issues

1. Whether periodic reductions in releases from Palisades Dam below 1,000 cfs constitute a “major Federal action” under NEPA requiring preparation of an EIS.
2. If so, whether those reductions “significantly affect” the human environment so as to trigger NEPA’s EIS requirement.

## Decision

- The Ninth Circuit affirmed the judgment for the Bureau and intervening irrigation entities.
- The court held that periodic flow adjustments, including reductions below 1,000 cfs, were not a “major Federal action” within NEPA’s meaning.
- Because the threshold “major Federal action” requirement was not met, the court did not reach whether low flows significantly affected the environment.

## Legal Principles

- NEPA’s EIS requirement applies only to “major Federal action”; absent such action, NEPA does not require an EIS even if environmental effects are alleged.
- Routine, periodic operational decisions within an ongoing, long-established, congressionally authorized federal water project may be treated as implementation of existing authority rather than a new major federal action.
- Where the challenged conduct is continuing project operation rather than a new proposal or discrete federal undertaking, NEPA may not compel renewed EIS review solely due to operational adjustments.

## Conclusion

The Ninth Circuit concluded that the Bureau’s periodic reductions in Palisades Dam releases below 1,000 cfs were part of longstanding project operations and not a “major Federal action,” so NEPA did not require an EIS for those flow adjustments.


Upper Snake River Chapter of Trout Unlimited v. Hodel, 921 F.2d 232 (9th Cir. 1990)