10 States File Amicus Brief in Agua Caliente Groundwater Lawsuit

In early August 2017, the State of Nevada was joined by the states of Arizona, Arkansas, Idaho, Nebraska, North Dakota, South Dakota, Texas, Wisconsin, and Wyoming in filing an amicus curiae brief in Coachella Valley Water District, et al. v. Agua Caliente Band of Cahuilla Indians and Desert Water Agency, et al. v. Agua Caliente Band of Cahuilla Indians.

The states filed the amicus brief in order to protect their sovereign interest in their respective water rights. They note that state and federal courts have disparate conclusions about the extent of the Winters doctrine stating, “The split of authority could not be wider or more fractured.” State courts have ruled that Winters does not apply to groundwater or that it applies only in very limited circumstances, while the federal appellate court has ruled that “state water rights are preempted by federal reserved rights.” The states advocate for the U.S. Supreme Court to grant certiorari in order to resolve this conflict. They seek a definitive answer about whether the implied federal reserved water rights under Winters always preempts state regulation of groundwater in light of Congress’ practice of deferring to state water law and the U.S. Supreme Court’s history of taking a “narrow construction” of the reserved water rights doctrine. The amicus brief followed an appellate court decision in favor of the Agua Caliente Band of Cahuilla Indians (“Agua Caliente” or “tribe”) and appeal by Coachella Valley Water District (“CVWD”) and Desert Water Agency (“DWA”) to the U.S. Supreme Court.

The Appeals Court Decision

On March 7, 2017, the United States Court of Appeals for the Ninth Circuit issued a decision affirming the district court decision. The appellate court divided its analysis into three parts:

  1. Addresses “whether the United States intended to reserve water when it created the Tribe’s reservation”
  1. Addresses “whether the reserved rights doctrine encompasses groundwater”
  1. Addresses whether the tribe’s other water sources—including its correlative rights under state law and its water under the Whitewater River Decree—or its historic lack of drilling for groundwater impact the court’s evaluation of the other two points.

In addressing the first question, the court stated, “Without water, the underlying purpose—to establish a home and support an agrarian society—would be entirely defeated. Put differently, the primary purpose underlying the establishment of the reservation was to create a home for the Tribe, and water was necessarily implicated in that purpose.” The court, therefore, concluded that the United States did implicitly reserve water when it established the tribe’s reservation.

In addressing the second question, the court relies on a key limitation of the reserved water rights doctrine: appurtenance. The reserved water rights doctrine specifies that the water reserved for the federally reserved land must be appurtenant to the land. The court maintains that appurtenance requires the reserved water rights to be tied to the reservation, but it is not limited to surface water, and that many areas of the west have access only to groundwater. The court concludes, “…surface water in the Coachella Valley is minimal or entirely lacking for most of the year. Thus, survival is conditioned on access to water—and a reservation without an adequate source of surface water must be able to access groundwater.…The creation of the Agua Caliente Reservation therefore carried with it an implied right to use water from the Coachella Valley aquifer.”

The third question focuses on points made by CVWD and DWA to support their argument that the tribe does not need a federal reserved water right. Attorneys for the agencies argued that the tribe has correlative state water rights, has not drilled for groundwater on the reservation, and receives surface water under the Whitewater River Decree. The court rejected these points stating, “First, state water rights are preempted by federal reserved rights…Second, the fact that the Tribe did not historically access groundwater does not destroy its right to groundwater now…And third, the [previous case law] does not ask if water is currently needed to sustain the reservation; it asks whether water was envisioned as necessary for the reservation’s purpose at the time the reservation was created.”

Petitioning the U.S. Supreme Court

CVWD and DWA each filed a petition for writ of certiorari in early July 2017. DWA asks the U.S. Supreme Court to answer three questions that directly address the decision rendered by the appellate court:

  1. Whether the appellate court correctly interpreted the Supreme Court decision in United States v. New Mexico (1978) when it determined that a federal reserved right exists if the purpose of the reservation envisions the use of water
  1. Whether the Winters doctrine applies to groundwater
  1. Whether the tribe’s claim of a federal reserved right is necessary given that it has access to groundwater under state law.

CVWD points out conflict in existing case law. The Wyoming Supreme Court has ruled that Winters does not apply to groundwater, while the Arizona Supreme Court has ruled that it can apply to groundwater under certain limited circumstances. CVWD argues that the appellate court contradicts both state court positions by holding that Winters fully preempts state law and applies to groundwater regardless of state-law protections, and asks a singular question:

“Whether, when, and to what extent the federal reserved right doctrine recognized in [Winters] preempts state law regulation of groundwater.”

Additional Background

The case began in May 2013 when the tribe filed a lawsuit against CVWD and DWA arguing that its federal reserved water rights under the Winters doctrine extends to groundwater. The Winters doctrine applies the concept of federal reserved water rights to Indian reservations—so when the federal government reserved the land for the tribe, it also reserved sufficient water rights to meet the purpose of that land. The tribe also argued that it has an aboriginal right of occupancy, which would deem its water rights to be the most senior in the valley, and claimed that CVWD has been impairing the quality of the groundwater in the basin by recharging raw Colorado River water in an attempt to mitigate overdraft conditions. The parties stipulated to breaking the case into three phases to address three different substantive issues. Phase I addresses the question of whether federal reservation of water rights extends to groundwater and whether the tribe has an aboriginal right of occupancy. Phase II will address whether the tribe owns “pore space” in the groundwater basin underneath reservation lands and whether a right to a quantity of groundwater encompasses a right to a certain quality of groundwater. Phase III will attempt to quantify any identified groundwater rights.

U.S. District Court Judge Jesus G. Bernal issued an order in Phase 1 in March 2015 concluding that the tribe’s federal reserved water right may extend to groundwater, but also stated that the aboriginal right of occupancy had been long extinguished. In February 2016, Judge Bernal issued a summary judgement rejecting the agencies’ defenses against the tribe’s request for a declaration of federally reserved water rights. CVWD and DWA appealed the district court decision.  (For more on the March 2015 court order, see “U.S. District Court Issues Order in Phase I of Agua Caliente Case,” Journal of Water May 2015. For more on the February 2016 summary judgement, see “U.S. District Court Judge Issues Summary Judgement in Agua Caliente Groundwater Suit,” Journal of Water March 2016).


Written by Marta L. Weismann