1. Workers are digging a water tunnel through bedrock deep beneath Manhattan as part of a $6 billion project that began in 1970.

2. With their round, rimmed helmets and weathered faces, the muddy workers have the look of World War I doughboys.

3. When complete, the tunnel will be able to handle the roughly one billion gallons of water a day used in New York City

4. A worker rides a rail car that is used to carry equipment and debris from the tunnel.

5. Mohammed Abbaszadeh, left, known as Mike, and Tony Selkirk in the tunnel.

6. Next Monday, workers will embark on a yearlong regimen of dynamite blasting throughout Midtown and Lower Manhattan to create nine water supply shafts designed to connect the water tunnel to mains under city streets and to provide workers access to the tunnels.

7. The portion of the tunnel running through the Bronx and down the West Side of Manhattan is complete. Many tunnel workers are now focusing on a section that heads downtown and hooks back up to East 59th Street, with a crosstown spur in Midtown.