Today The Story begins a week-long exploration of water. We start by checking in with Charles Fishman, author of The Big Thirst. Also, when you think of Las Vegas, you might assume that making a city green in a desert would be a tale of colossal waste. There may be some truth to that, but Pat Mulroy will surprise you. She manages the city's water, and she's had a lot of success getting people to pull out their grass and dramatically cut back on water use.