In July 2010, Expedition Blue Planet explored the headwaters of the Colorado River to investigate how this mighty river is overallocated from the moment its waters touch the ground up in the Rocky Mountains, where the continental divide rises like spine and demarcates the Mississippi watershed that lies to the East from the Colorado watershed that falls to the West. Today we find that this iconic river still means life for the 20 million people that live in its basin, just as it did for the Native Americans, just as it did for the settlers who drove West and claimed it as their own. But the truth is, the minute it touches the ground we've allocated every drop and too often we're not even judicious in how we use it. In this short film, we speak to key voices in the headwaters region and chart the path of the river's flow to investigate water use and management issues in the American West. Here, it's all about what's downstream.