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Know the West

The Latest: Pumping Arizona's rivers dry?


Last July, Arizona's state water board approved a large new development in Sierra Vista that would pump 3,300 acre feet of groundwater per year -- despite evidence that such pumping could decrease flow in the San Pedro River, one of the West's healthiest desert rivers. Environmentalists appealed the decision; so did the Bureau of Land Management, to protect congressionally-granted federal water rights in the river (HCN, 2/18/13, "The BLM fights for the Southwest's last free-flowing river").

In April, the water board OK'd the development again, after a judge dismissed the appeal. Opponents say they'll take the case to the state's superior court. "This case is huge, and not only for the San Pedro," said Robin Silver of the nonprofit Center for Biological Diversity. "It has precedence for any federal lands that have water rights being challenged by the malfeasance of the state." Meanwhile, a new study shows that groundwater pumping has reduced the flow of another major Arizona river, the Verde.