Whether § 7 of the Endangered Species Act applied to TVA's completion and operation of the nearly completed Tellico Dam.
Holding
Yes. Operation of the dam would violate § 7 because it would jeopardize the snail darter's continued existence and destroy or modify its designated critical habitat.
Reasoning
Section 7 expressly required every federal agency to take the action necessary to ensure that actions it authorized, funded, or carried out did not jeopardize an endangered species or destroy or modify its critical habitat. Closing Tellico Dam's gates was plainly an agency action being carried out under federal authorization and funding. Because the Secretary had validly determined that the reservoir would destroy the snail darter's only known habitat, TVA's proposed operation directly conflicted with the statute's command.
The Court treated the Secretary of the Interior's listing of the snail darter and designation of its critical habitat as controlling premises. TVA had not challenged those administrative determinations, and the record supported the conclusion that impoundment would eradicate the known population or destroy the habitat essential to its survival.
The ESA's structure and legislative history confirmed the text. Congress deliberately removed qualifying language from earlier drafts that would have required agencies to protect species only when practicable or consistent with their primary missions. That omission showed a conscious choice to give endangered species priority over agencies' competing project objectives.
Congress enacted the ESA to halt and reverse extinction, recognizing that the value of species and genetic diversity was incalculable. Courts therefore could not weigh a known dollar loss from stopping a project against the asserted value of preserving a species. Congress, not the judiciary, made that policy judgment when it enacted the statute.
The statute contained limited, express hardship exemptions, but none applied to federal agencies or to Tellico. The absence of a relevant exemption reinforced the conclusion that courts could not create one for projects that were expensive, longstanding, or nearly complete.