Texas v. New Mexico
Headline: Interstate water ruling lets New Mexico count evaporated Pecos River water as delivery credit when stored at Texas’s request, denying Texas’s challenge and shaping how the two states account for stored water.
Holding: The Court denied Texas’s motion, upheld the River Master, and ruled that New Mexico is entitled to delivery credit for water that evaporated while stored in New Mexico at Texas’s request.
- Allows New Mexico to get delivery credit for evaporation when Texas requested storage.
- Affirms River Master procedures when both States agreed to postpone dispute resolution.
- Affects how state water managers account for stored and lost river water.
Summary
Background
Texas and New Mexico share the Pecos River under a 1949 Compact that divides the river’s water. The Court appointed a neutral River Master and adopted a Manual in 1988 to calculate deliveries. After a 2014 tropical storm, Texas asked New Mexico to hold some flows at the Brantley Reservoir in New Mexico to prevent flooding; New Mexico agreed and said the water belonged to Texas. While stored, about 21,000 acre-feet evaporated. The States negotiated for years without agreement, the River Master postponed a final resolution with the States’ consent, and New Mexico filed a motion in 2018 seeking delivery credit for the evaporated water.
Reasoning
The Court faced a simple practical question: must New Mexico get credit when water evaporates while it is stored in New Mexico at Texas’s request? The River Master relied on §C.5 of the Manual, which says that when Texas allocation is stored in New Mexico at Texas’s request, the delivery obligation is reduced by reservoir losses. The Court agreed with the River Master: Texas requested storage, New Mexico stored the water, and §C.5 applies. The Court also rejected Texas’s timeliness objection because both States had agreed to postpone resolution while negotiating. The Court therefore denied Texas’s motion for review and affirmed the River Master’s decision awarding New Mexico credit.
Real world impact
The decision affects how the two States and water managers count stored and lost water, especially after emergency storage requests or flood-control operations. It reinforces the River Master’s role and the Manual’s rule that evaporation from storage at another State’s request can reduce delivery obligations.
Dissents or concurrances
Justice Alito agreed the timeliness objection failed but would remand for further fact-finding about the federal Bureau of Reclamation’s role, flood-control purpose, and proper accounting categories.
Ask about this case
Ask questions about the entire case, including all opinions (majority, concurrences, dissents).
What was the Court's main decision and reasoning?
How did the dissenting opinions differ from the majority?
What are the practical implications of this ruling?