The Colorado River watershed, a vital source of water for seven U.S. states and Mexico, is in historic crisis. This major river system irrigates vast agricultural lands in the West, supports cities, generates hydroelectricity and is used by 40 million people. But since the turn of the century natural runoff in the watershed has dropped by 13 percent, and the two largest reservoirs in the system haven’t been anywhere near full since 1999. Drought, overuse and climate change mean that water levels will likely remain seriously low, even despite the occasional wet period, according to Jack Schmidt from Center for Colorado River Studies. In a recent special edition of PBS Newshour, Schmidt explained why matching supply and demand is so difficult in the high-stakes political environment in which future management is now being negotiated on a state and federal level.