A judge has sided with water conservationists who say a large, planned development in Sierra Vista is not sustainable because it lacks an adequate water supply.

THe ruling by Maricopa County Superior Court Judge Crane McClennen reversed a 2013 decision by the Arizona Department of Water Resources that found there is enough water in the San Pedro River to sustain 7,000 new homes and offices in Sierra Vista for at least 100 years.

The federal Bureau of Land Management and conservationists appealed the ruling, saying the Department of Water Resources decision didn't take into account a decades-old legal battle over San Pedro River water rights. They argue there is evidence that the long-term water supply will be inadequate.