Fixing New York's Water System: Extreme Plumbing

The five-year, $22 million diving project is underway today, and that means six lucky divers are presently 700 feet beneath the NYC surface, trying to find where one of the bigger leaks is hiding. They're living in a 24-foot pressurized tube that includes "showers, a television and a Nerf basketball hoop," and they're breathing air that is 97.5% helium and 2.5% oxygen.

Why helium? Well, since these lucky ducks will be in a pressurized environment for an extended period of time, they need to employ what's known as "saturation diving." Long story short, this technique allows the divers to go 700 feet down, and return to their living quarters without having to worry about repeated decompression sessions.

When they're on break, the divers can have whatever meals they like, although helium tends to dull human taste buds. Tabasco sauce is their best friend, apparently, along with jalapenos and salsa.

The other day, one of the divers, A. W. McAfee, moved about as gracefully as anyone could in that much water, slowly fixing a monkey wrench onto a screw wedged in a block of concrete, then taking a mallet to whack it free. As Mr. McAfee did this again and again, a camera on his helmet broadcast his slow ballet and heavy breathing in near-darkness to a video feed far above in a brick building, where his bosses sat, riveted, searching for clues.