On June 21, 2024, the United States Supreme Court issued a landmark decision in Texas v. New Mexico, No. 141, Orig, (2024), a case that has long simmered over the apportionment of water in the Rio Grande River. This ruling marks a significant chapter in the ongoing water dispute between Texas and New Mexico, both of whom are signatories to the 1938 Rio Grande Compact. This compact, which also includes Colorado, was established to equitably divide the waters of the Rio Grande River among the three states.
Under the Compact, New Mexico is mandated to deliver a specified amount of water annually to the Elephant Butte Reservoir, managed by the federal Bureau of Reclamation (Reclamation). This water is then released from the reservoir to meet the needs of Texas. However, Texas took legal action against New Mexico in 2013, alleging that excessive groundwater pumping by New Mexico was depleting the Rio Grande’s water supplies intended for Texas. This legal battle intensified when the federal government was allowed to intervene, citing its vested interest in ensuring New Mexico adhered to the Compact’s terms.
In a surprising twist in November 2022, Texas and New Mexico reached a consent decree aimed at resolving all claims in the dispute while allowing New Mexico to continue its groundwater pumping. Despite the federal government’s opposition, both states sought the Supreme Court’s approval of the decree. However, the Court declined to settle the dispute, emphasizing that the federal government still had significant interests to pursue. Approving the consent decree, the Court noted, would effectively nullify the federal government’s claims without its consent.
The Rio Grande River, originating in the San Juan Mountains of southern Colorado, traverses New Mexico before flowing into Texas and eventually reaching the Gulf of Mexico. Covering a drainage basin of over 180,000 square miles, the river is a critical water source, irrigating approximately 178,000 acres of land and providing electric power to local communities. The river’s importance was recognized as early as 1906 when the United States and Mexico entered into a treaty requiring the U.S. to deliver 60,000 acre-feet of Rio Grande water to Mexico annually. This commitment led to the construction of the Elephant Butte Dam and Reservoir in New Mexico, a cornerstone of the Rio Grande Project managed by Reclamation.
In addition to the treaty with Mexico, the federal government is bound by the Downstream Contracts, which obligate it to deliver water annually to the Elephant Butte Irrigation District in New Mexico and the El Paso County Water Improvement District No. 1 in Texas. These contracts require Reclamation to provide water to irrigate 88,000 acres in the former and 67,000 acres in the latter. The 1938 Rio Grande Compact further divided the remaining water rights among Colorado, New Mexico, and Texas, with New Mexico required to deliver water to Elephant Butte Reservoir rather than directly to the Texas state line.
Drought conditions that set in about a decade after the Compact’s signing led to increased groundwater pumping in New Mexico, impacting Reclamation’s water releases from Elephant Butte. This practice intercepted return flows that would otherwise replenish the Rio Grande riverbed, forcing Reclamation to release more water to meet its obligations. Texas’s 2013 lawsuit claimed that New Mexico’s groundwater pumping exceeded the levels anticipated in 1938, thus violating the Compact and reducing water deliveries to Texas.
The federal government, siding with Texas, argued that New Mexico’s actions interfered with Reclamation’s ability to fulfill its contracted deliveries and obligations to Mexico. Both Texas and the federal government sought an injunction to halt New Mexico’s excessive groundwater pumping. Despite a proposed consent decree between Texas and New Mexico, the federal government opposed it, leading to the Supreme Court’s involvement.
In a narrow 5-4 decision, the Supreme Court declined to approve the consent decree, allowing the federal government to continue pursuing its claims. The Court’s decision hinged on whether the federal government had valid claims under the 1938 Compact and whether the proposed consent decree would address those claims. The Court affirmed the federal government’s right to intervene, given its role as an “agent” of the Compact, which is closely tied to the Downstream Contracts and the Rio Grande Project.
This ruling underscores the complexities of interstate water compacts and the federal government’s role in ensuring compliance. As the legal battle continues, the decision highlights the ongoing challenges in managing shared water resources in an era of increasing scarcity and competing demands.