Center for Biological Diversity

For Immediate Release, December 4, 2023


Robin Silver, (928) 310-6713,

Appeals Court Throws Out Arizona Fort’s Groundwater Pumping Credits Threatening San Pedro River

TUCSON, Ariz.— A federal appeals court today sided with conservation groups in their challenge to the U.S. Fish and Wildlife Service granting fake groundwater credits to the U.S. Army’s Fort Huachuca that fail to return water to the imperiled San Pedro River in Arizona.

“This decision is a victory for the San Pedro River and the plants and animals that depend on it,” said Robin Silver a cofounder of the Center for Biological Diversity. “The Army has known since 1970 that growth at Fort Huachuca was unsustainable and that securing enough water for the base would be problematic. Every Fort Huachuca mission except the electronic proving grounds can be accomplished elsewhere without harming our national defense.”

Today’s decision reverses a lower court ruling upholding the groundwater credits and orders the U.S. Army and Fish and Wildlife Service to reevaluate its water-savings analysis in a new biological opinion.

In September 2022 the Center for Biological Diversity, Maricopa Audubon Society and the Sierra Club filed an appeal with the 9th U.S. Circuit Court of Appeals saying the lower court’s March 2022 ruling wrongly gave the Army base credit for ending groundwater pumping in an area where it had been terminated a decade earlier. The court approved the mitigation credits based on its belief that groundwater pumping was “likely” to restart in that area, even though previous court rulings require it must be “certain to occur.”

The San Pedro River and its endangered species are in trouble because of excessive, uncontrolled groundwater pumping in the Fort Huachuca and Sierra Vista areas.

Fort Huachuca's off-post groundwater pumping is the single greatest contributor to the San Pedro River's demise. In 2013 Fort Huachuca was facing inevitable downsizing because of its inability to mitigate its excessive, unsustainable groundwater pumping. Fort Huachuca intelligence operatives convinced Fish and Wildlife officials to grant fake water credits.

The conservation groups’ appeal said Fish and Wildlife officials violated their own their water credit policy, as well as a directive to the Fort that “[t]o adequately address the overdraft of groundwater in the Upper San Pedro Basin and insure the health of the San Pedro River and the species that depend on it, some current uses of water must cease.”

Agency officials also went against their own biological opinion that conservation easements do not increase water flows in adjoining streams “unless an active water use is retired.”

In today’s decision the court held that “the government… provided little evidence and relied mostly on speculation to claim water savings. And because the government cannot claim these water savings, its no-jeopardy determination about the protected wildlife is arbitrary and capricious.”

As the last free-flowing desert river in the Southwest, the San Pedro River is home to endangered species that rely on it to survive, including southwestern willow flycatchers, Huachuca water umbel, desert pupfish, loach minnows, spikedace, yellow-billed cuckoos, Arizona eryngo and northern Mexican garter snakes.

“What a great day for the San Pedro!” said Maricopa Audubon Conservation Chair Charles Babbitt. “The appeals court has just thrown a much-needed lifeline to one of America’s truly great last places and the beautiful birds it nourishes. It’s time for Fort Huachuca to be downsized.”

Earthjustice represented the Center, Maricopa Audubon and Sierra Club in this lawsuit.

San Pedro River
The San Pedro River. Photo credit: Robin Silver, Center for Biological Diversity. Image is available for media use.

The Center for Biological Diversity is a national, nonprofit conservation organization with more than 1.7 million members and online activists dedicated to the protection of endangered species and wild places.

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