Tennessee Valley Authority v. Hill, 437 U.S. 153 (1978) (U.S. Supreme Court)
Tennessee Valley Authority v. Hill is a landmark Supreme Court decision at the intersection of environmental protection, statutory interpretation, and separation of powers.
Does § 7 of the Endangered Species Act require a federal court to enjoin completion and operation of a nearly finished federal project that would likely eradicate an endangered species and destroy its critical habitat, notwithstanding significant sunk costs and ongoing congressional appropriations for the project?
ESA § 7 imposes a mandatory, affirmative duty on every federal agency to "insure" that any action authorized, funded, or carried out by the agency is not likely to jeopardize the continued existence of any endangered species or result in the destruction or modification of its designated critical habitat. This duty admits of no ad hoc cost-benefit balancing by agencies or courts, and courts must enforce the statute as written. Appropriations measures and committee reports do not amend or repeal substantive law absent a clear and express statement from Congress. When an ongoing or imminent agency action violates § 7, injunctive relief is the appropriate remedy to give effect to Congress's directive.
Yes. The ESA requires halting the Tellico Dam project because its completion and operation would jeopardize the snail darter and destroy its critical habitat. The statute affords endangered species priority over competing project interests "whatever the cost," and neither equitable balancing nor continued appropriations can override this clear congressional command. The Supreme Court affirmed the Sixth Circuit's injunction.
TVA v. Hill is foundational in environmental law and statutory interpretation. It cements the primacy of clear statutory text over equitable balancing and agency pragmatism, especially when Congress has spoken in uncompromising terms. The decision also reinforces the separation of powers by insisting that appropriations cannot silently amend substantive law and that courts must enforce Congress's priorities, even in the face of considerable economic and political pressure. Doctrinally, the case sets the baseline understanding of ESA § 7: federal agencies must avoid jeopardy and critical habitat destruction, and courts will enforce that mandate through injunctions when necessary. Institutionally, the ruling prompted the 1978 amendments to the ESA creating the Endangered Species Committee (the so-called "God Squad") to allow limited exemptions in extraordinary circumstances. Although Congress later enacted a specific rider permitting completion of the Tellico Dam and the snail darter was ultimately recovered and delisted decades later, TVA v. Hill remains the leading example of courts giving full effect to a strong environmental statute.