Tunnel Boring Completed on No. 7 Subway Extension

With a loud rumble and several splashes, a giant boring machine finished the last bit of tunnel for the No. 7 subway extension at about 4:15 this afternoon.

A pair of tunnel boring machines started drilling the tunnel underground in Chelsea last June and ended Thursday, underneath the Port Authority bus terminal at 8th avenue and 41st Street.

Mayor Michael Bloomberg and MTA Chairman Jay Walder were on hand to witness the wall crashing down, as well as a smattering of construction workers, known as sandhogs, who've been working on the tunnel. They gathered in the underground cavern -- one side had a large orange circle painted on it marking the outline of what will become the westbound tunnel.

A little after 4 p.m., the low rumbling of the tunnel boring machine could be heard from the other side of the wall. The rumbling grew louder as pieces of rock fell off into dusty piles below. Then, a large rock shaped like a pizza slice -- about ten feet wide -- fell off of the circle, revealing the giant drum rotating behind it. More pieces crumbled. The crowd cheered.

Bloomberg told reporters before the event that the final drilling didn't mark the end of the project but the "end of the beginning." 

"It will bring us one step closer to the moment about three years from now when the No. 7 train will stop at Times Square and then continue on to the new 34th Street station on the Far West Side," he said. 

The city is paying for the $2.1 billion project by issuing bonds. It will pay the bonds back with some of the real estate taxes it gains from new development on the Far West Side that wouldn't have taken place without better transit.

That financial role made Bloomberg the master of ceremonies at the event, as he was at two other events in the past 18 months. An associate says the mayor's been eager to show real estate developers that the subway extension will become a reality soon. The point of the project is to spur construction of office buildings on Manhattan's Far West Side. London attempted something similar in the 1990s by extending the Jubilee Line in order to turn Canary Wharf into more of a business district.

Bloomberg also got the right to name the two tunnel boring machines when they set off on the 4,500-foot journey last summer. He named them Emma and Georgina after his two daughters. It wasn't quite clear which one did the honors on Thursday. The other machine completed the eastbound tunnel earlier this year.

The MTA, however, will be responsible for funding the added line once the extension goes into service, which is expected to be by the end of 2013.

MTA Chairman Jay Walder said the increased cost will be "incremental" and wasn't of much concern to the agency, despite its ongoing financial troubles.