—by Alan Dulaney
A recent Ninth Circuit Court ruling shakes the basic structure of Western water regulation by introducing the concept of prior rights into groundwater law where it was never seen before.
In late November, the U.S. Supreme Court declined to hear an appeal from water management agencies near Palm Springs, California, concerning groundwater rights under the Winters Doctrine. The Winters Doctrine was established by the Supreme Court in 1908 and affirmed that tribes are entitled to sufficient water for their reservations’ purposes. But it was always applied to surface water, in keeping with the West’s bifurcation of surface and groundwater rights and laws. The Agua Caliente tribe originally sued in 2013 to establish authority over groundwater on their 31,500-acre reservation, and won. The defendants, Desert Water Agency and Coachella Valley Water District, then appealed, based on longstanding state control of water management… and lost.
The Justices let stand the ruling from the Ninth Circuit Court of Appeals, which expands the Winters Doctrine to groundwater for the first time. And not just groundwater for tribal lands and reservations, but for all federally reserved lands, such as national parks, forests, and military reservations. Arizona has a lot of federally reserved lands, tribal and otherwise, so it joined nine other states in a “friend of the court” brief seeking to preserve state authority over water. The Ninth Circuit Court ruling shakes the basic structure of Western water regulation by introducing the concept of prior rights into groundwater law where it was never seen before.
Implications fall like leaves from an autumn aspen. How much groundwater is reserved? If a pumping well impacts other wells with reserved rights, must it be shut down? What if pumping within a groundwater basin impacts groundwater chemistry (a major component of the Agua Caliente complaint)? What are the effects on recharging into an aquifer where federal entities have a prior claim? Do federally reserved rights (remember their priority) give federal entities a disproportionate share in groundwater management decisions? If prioritizing groundwater rights has never been considered under state law before — such as the case for Arizona outside of the AMAs — how is it now to be instituted, and by whom?
In 2016, I wrote about the Tribute master-planned community near Sierra Vista in Cochise County, where the BLM intervened against a favorable ADWR determination on adequate water supply based on federally reserved surface-water rights along the San Pedro. Had it been armed then with this new interpretation of priority groundwater rights, the BLM could have made a far stronger argument. It will not be long, I predict, before federal agencies and certainly tribal entities assert their newly affirmed priority groundwater rights to influence management decisions on wells and recharge. In the meantime, the courts will address the issues of groundwater quantity attached to federally reserved rights, storage space in aquifers, and water quality protections, all concepts that will need technical input.
Amidst all the confusion, one thing is clear: We’re going to need a lot more hydrologists.