What do two rivers in the Southeast and California have in common? Both are threatened by battles over their water.  

The Apalachicola-Chattahoochee-Flint Basin in Alabama, Georgia, and Florida tops a new list as the most endangered river in the U.S. this year, according to an annual report from the Washington, D.C.-based conservation group American Rivers. Second most endangered is the San Joaquin River in northern and central California.

"Both rivers suffer from increasing conflict among stakeholders who depend on their water," including cities, farmers, and wildlife, says Chris Williams, a senior vice president at American Rivers. "And these issues are exacerbated by population growth and climate change."

Other rivers high on the list include the Susquehanna in Maryland and Pennsylvania, the Smith