Supreme Court of the United States

Nebraska v. Wyoming

April 20, 1993507 U.S. 584

Summary

Justice O’Connor delivered the unanimous opinion of the Court in this original interstate water-rights action. The Court overruled all exceptions to the Special Master’s reports, granted Nebraska and the United States summary judgment recognizing the Inland Lakes’ December 6, 1904, priority and associated storage practices, and granted Nebraska partial summary judgment that the decree imposes no absolute ceilings on diversions by canals in the pivotal reach. It denied all other summary judgment motions. The Court distinguished enforcement of existing decree rights, which requires no showing of injury, from modification creating new rights, which requires substantial injury. It concluded that the decree did not resolve rights to excess Laramie River flows and left the Deer Creek dispute for further factual development without definitively interpreting the decree’s municipal-use exception. There were no separate opinions.

Holding

  • Scope of Nebraska’s petition.. The litigation is not confined to enforcement of previously established rights and may include requests to modify the decree.
  • Standards governing enforcement and modification.. Enforcement of an existing decree right does not require proof of injury, but a request to reweigh equities and establish new rights requires a showing of substantial injury.
  • Inland Lakes priority and storage rights.. The Inland Lakes have a December 6, 1904, priority protecting diversion of 46,000 acre-feet during October, November, and April, including necessary temporary storage in Guernsey and Glendo Reservoirs.
  • Rights to excess Laramie River waters.. The earlier decrees neither authorize Wyoming entirely to dewater the Laramie nor establish Nebraska’s right to excess Laramie flows. Injunctive relief would modify the North Platte decree and requires sufficient evidence of threatened substantial injury.
  • Summary judgment concerning Deer Creek.. Wyoming is not entitled to summary judgment concerning Deer Creek; the Court need not definitively interpret the municipal-use exception at this stage.
  • Absolute ceilings on canal diversions.. The decree does not impose absolute ceilings on diversions by canals taking water in the pivotal reach.

Docket 108 ORIG

Cited authorities

  • Rule 56(c) of the Federal Rules of Civil Procedure
  • Rule 17.2

Cited by

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