Making sandwiches all day seems like a peaceful enough job. In the background I can hear many different hums and beeps: the radio, chopping, boiling, refrigeration, customers and so on. None of this bothers me in the slightest. There is one sound that stands out above all else: the ceaseless drip of our kitchen faucets.

Out of curiosity and frustration, I put a large measuring cup under the drip and left it for a half-hour. Then, with much multiplying and division, I came out with this: 7117.5 gallons of water are wasted from that one tap each year. This needs to stop, and I'm going to do it.