For the second time in a decade, federal courts are disagreeing with an official biological opinion that groundwater pumping in the Sierra Vista area won't jeopardize two endangered species living along the San Pedro River.
An environmental group that filed suit said Tuesday the new ruling makes it clear that the area's leaders can't protect the river from pumping's impacts without scaling back U.S. Army operations at Fort Huachuca.
U.S. Fish and Wildlife Service and Army officials would not comment on the ruling. It overturns their 2007 biological opinion on how pumping for the fort would affect the river.
But a U.S. Geological Survey official, Bruce Gungle, a hydrologist and chief of the survey's San Pedro project, acknowledged Tuesday there isn't much more the region can do to conserve water to protect the river, although other measures such as a long-discussed, very expensive plan to import Central Arizona Project water could help.
The San Pedro is the last major free-flowing Southwestern desert river.
In Friday's ruling, U.S. District Judge A. Wallace Tashima said:
• The biological opinion "committed legal error" by failing to analyze the effects of the fort's actions on whether the endangered Southwestern willow flycatcher and the Huachuca water umbel will recover from their imperiled status.
• The Wildlife Service's opinion relied, in violation of the law, on "uncertain and unspecified" measures to ease the pumping. The opinion mentioned 26 water-related measures, but the judge said it is difficult to determine which of those are actually planned, and that nearly one-third of the projects aren't financed.
• The Army's reliance on this 2007 opinion was "arbitrary and capricious," and the Army violated its duty under the Endangered Species Act to ensure its operations don't jeopardize the species.
The ruling responded to a suit brought by the Center for Biological Diversity and the Maricopa Audubon Society. In 2002, in response to an earlier suit filed by the center, another judge tossed out an earlier Wildlife Service biological opinion, forcing the 2007 rewrite.
The Sierra Vista area pumps about 6,100 acre-feet more water than is replenished by rainfall and other means, studies have shown.
The ruling's significance should be "that it is finally clear that they can't come up with enough mitigation measures to preserve the river with the fort's current troop strength," said Robin Silver, the Center for Biological Diversity's conservation chairman. "In order to save the river, they need to reduce the number of missions at Fort Huachuca."
Fort Huachuca had about 6,225 employees at the start of this year, according to the Star 200 survey.
As for the court ruling, "we haven't had a chance to fully review the decision yet," Fort Huachuca spokeswoman Tanja Linton said Tuesday. "Once we've had an opportunity to do that, we will provide a comment."
The government hasn't decided whether to appeal the ruling, and the Wildlife Service has no reaction "until we've studied and digested it and gotten advice from our attorneys," said Steve Spangle, its field supervisor in Arizona.
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Contact reporter Tony Davis at email@example.com or 806-7746.