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A tribe wins rights to contested groundwater in court

A major federal court decision acknowledges that tribes have priority rights to groundwater — and could limit how much other users can take.


On the surface, Southern California’s Coachella Valley seems like a cushy, vibrant paradise. A short jaunt from Los Angeles, it’s known for its hot springs, golf courses and uber-hip music festival. But the popular retreat for celebrities, politicians and wealthy jetsetters is something of a mirage — at least where water is concerned. It’s a desert that receives a paltry three to five inches of rain a year.

To live here, people have always relied on groundwater, whether in historical Native American settlements or the modern resort city of Palm Springs. Surging population growth and tourism in recent decades have only increased demand. Local utilities now supply water to roughly 400,000 full-time residents, 121 golf courses, and 66,000 acres of dates, lemons, and other crops, and it’s taxing the aquifer. A recent NASA study found that the aquifer underlying the Coachella Valley has dropped by around 62 feet since 1960, despite programs that pipe Colorado River water underground to offset the depletions.

The Coachella Valley, California

A groundwater recharge facility for the Coachella Valley adds water imported from the Colorado River to the valley’s main aquifer and prevents the land from sinking and damaging the surrounding infrastructure.
Brent Stirton/Getty Images

The Agua Caliente Band of Cahuilla Indians, who have called the valley home for centuries, have been anxious about the state of the water supply for years. In 2013, the tribe sued the Coachella Valley Water District and Desert Water Agency to halt groundwater pumping. And last month, the U.S. 9th Circuit Court of Appeals delivered a major victory to the tribe. The court said the tribe has legal rights to the groundwater — a decision that could restrict housing and resort development and set a precedent for water disputes between tribes and utilities across the West.

The 9th Circuit’s ruling is a big deal,” says Monte Mills, co-director of University of Montana’s Indian law clinic and one of 11 professors who penned a brief supporting the tribe’s claims. It’s the first time a federal appellate court has unequivocally recognized that tribes’ water rights extend to groundwater.

Tribal water rights stem from a 1908 U.S. Supreme Court ruling, Winters v. United States, which established that tribes’ rights to water are tied to the dates their reservations were created. Generally speaking, that means their water rights pre-date almost all other legal water claims. And in the Western system of allocating water, old rights mean power, since those who hold them are entitled to water before anyone with more recent claims. In the Coachella Valley, the tribe asserting its water rights, which date to 1876, could mean shorter supplies for everyone else.

The Agua Caliente have been raising concerns about the condition of the aquifer underlying the Coachella Valley for at least two decades,” says Steve Moore, co-counsel for the tribe, and an attorney with the Boulder, Colorado-based Native American Rights Fund. The matter ripened to the point that the tribe decided that their concerns were being ignored by the water districts and it was time to assert their rights in court.”

The Agua Caliente tribe isn’t concerned only about the quantity of water underground. The tribe also argues that the water districts’ system of replenishing the aquifer with Colorado River water, degrades water quality since the river water is saltier than the aquifer. Now, a federal district court will decide on potential water-quality protections for the aquifer, such as treating the river water before piping it underground. Then it will determine just how much groundwater the tribe is legally entitled to.

The water providers have questioned the tribe’s motivation, since it lacks any infrastructure to pump and transport groundwater, and hasn’t disclosed how it might use its share of water. A statement from the Desert Water Agency suggested the tribe could sell the water back to the utilities and drive up rates paid by consumers; the Coachella water district writes that the tribe’s claims could force customers to reduce water use, and potentially even lead to building moratoriums.

Heather Engel, a spokeswoman for the Coachella Valley Water District, adds that treating river water is unnecessary. While it’s true that the river water is saltier than the groundwater, Engel says, it also has lower traces of cancer-causing arsenic and chromium-6, which occur naturally in the groundwater but need to be treated when they exceed federal standards. Overall, the levels of these impurities are low. The district calls its drinking water “nearly pristine,” and minimally treats the groundwater before piping it to homes and businesses.

The two water districts have estimated that river water treatment or alternatives, such as building a new aqueduct to import water from a different source to replenish the aquifer, could cost up to $1.5 billion. That’s prohibitively expensive, Engel says. The utilities are now asking the U.S. Supreme Court to review the case, a final effort to reverse the decision.

Beyond the valley, tribes and water managers are paying attention. A ruling like this is good for the tribes,” says Dan Decker, tribal attorney for the Confederated Salish and Kootenai Tribes. Those western Montana tribes are finalizing a complex water-rights compact with the state and federal government to quantify their surface and groundwater rights, including gaining legal standing for wells drilled without permits on the reservation. Decker says the court’s decision bolsters the tribes’ case.

Water providers, however, are anxious. Should tribes make new claims to groundwater, they would get priority when courts calculate how much groundwater a basin’s users can draw. That process, known as “adjudication,” has been used to rein in groundwater mining that has often enabled development in the arid West. (Historically, groundwater has been much more loosely regulated than surface water.) Ultimately, the ruling could mean some utilities have to curtail or even halt groundwater pumping, leaving them scrambling for supplies.

Date palms in Coachella Valley, photographed by Dorothea Lange, 1937
Water providers in basins that have already completed the adjudication process, including 22 in California, would likely be spared such shakeups. But the Coachella Valley is one of the many basins in California and the West that have never gone through adjudication.

A lot of tribes around the country rely on groundwater and need to have access to quality groundwater in sufficient quantities for their reservations’ livelihoods and economic security,” Moore says. He adds that the ruling is also a boon to tribes’ sovereignty — the right to self-government — by acknowledging their right to manage natural resources connected to their reservations. “It reinforces for a lot of tribes what they have already believed.”

Joshua Zaffos is a HCN correspondent in Fort Collins, Colorado. Follow him @jzaffos.