Pete McBride spends a lot of time chasing water. Growing up on a Colorado cattle ranch, he chased irrigation water. Today he chases rivers—because he loves river trips— and he fears people are not aware of freshwater and the watersheds that feed them. He has worked in over 70 countries, been deported from one, followed four rivers source to sea, had an accidental standoff with an Amazonian electric eel, and kissed a flannelmouth sucker fish.

As I step forward into my darkest fears, I hear next to me the last sound I’d expect—giggling.  I am chest deep in inky, swamp water. Somewhere ahead of me is dry land I hope, but it is nowhere in sight. Each foot forward, I expect something to bite, zap, or attack me—a lurking viper,…