What is a River? What is in there, at the micro level? How does water move from the Earth’s surface through the ground, in and out of rivers? How much of the water on the planet is in rivers and how long is it there? This episode of What is a River is our annual episodic interview with an expert in their field. Dr Rebecca Neumann is a professor and researcher at the University of Washington in Seattle where she focuses on Hydrobiogeochemistry.