“I happened to be home with a high school girlfriend who, of all things, was a drinking water expert,” says this week's guest on "Story in the Public Square," Dr. Mona Hanna-Attisha. The friend asked if the pediatrician had heard about Flint's “new” water. She had. She had heard the reassurances of public officials that it was safe.Except it wasn’t. And she did research to prove it, and then set out to tell the world about it.