Here is the opinion in Agua Caliente Band of Cahuilla Indians v. Coachella Valley Water District:
The Coachella Valley Water District (“CVWD”) and the Desert Water Agency (“DWA”) (collectively, the “water agencies”) bring an interlocutory appeal of the district court’s grant of partial summary judgment in favor of the Agua Caliente Band of Cahuilla Indians (the “Tribe”) and the United States. The judgment declares that the United States impliedly reserved appurtenant water sources, including groundwater, when it created the Tribe’s reservation in California’s arid Coachella Valley. We agree. In affirming, we recognize that there is no controlling federal appellate authority addressing whether the reserved rights doctrine applies to groundwater. However, because we conclude that it does, we hold that the Tribe has a reserved right to groundwater underlying its reservation as a result of the purpose for which the reservation was established.