National Public Radio: So often, we take water for granted. We turn on the faucet and there it is. We assume it's our right in America to have water. And yet, water is a resource. It's not always where we need it, or there when we need it. Rivers don't follow political boundaries - they flow through states and over international borders. And there are endless demands for water: for agriculture, drinking, plumbing, manufacturing, to name just a few. And then there's the ecosystem that depends on water getting downstream....