Key supreme court cases
winters v. united states (1906)
This Supreme Court ruling formally conceptualized the notion of federal reserved water rights. Specifically, the Supreme Court held that the purpose of the Fort Belknap Native American reservation in Montana, assimilating Native Americans into an agrarian society, would be utterly useless without water. Consequently, the Court maintained Congress must have intended to reserve water along with land when the federal Indian reservation was created. This logic came to be known as the implied Winters doctrine but was thought only to apply in the context of Indian reservations [See, e.g., Frank J. Trelease, “Federal Re-served Water Rights Since PLLRC, 54 Denver U. L. Rev. 473, 475 (1977).]
Arizona v. California (1963)
Here, the Court held that the Winters doctrine applied to all federally reserved public lands, including national parks, recreation areas, forests, and wildlife refuges.
Cappaert v. United States (1976)
The Supreme Court constrained the scope of federal reserved water rights, holding that they only applied to the minimum quantity of water needed.
United States v. New Mexico (1978)
Federal reserved water rights were even further limited in that they were held to apply only to the minimum quantity of water needed to fulfill the primary purposes of a federal land reservation.