Colorado’s Yampa River is one of the last-free flowing rivers in the West and its water has long been eyed by the oil shale industry and by water agencies looking for new sources to tap to feed communities and farms hundreds of miles away. But recently Shell Oil shelved an application to divert water from the Yampa for mining, and a powerful Front Range water utility has put its interest in the Yampa on hold. This has environmentalists looking to seize the moment and drum up support to protect the river.