Gothamist
A non-profit newsroom, powered by WNYC.
Gothamist
Listen Live
News
2nd Ave Subway Tunnel Boring Machine: A Closer Look!
By
John Del Signore
Published Apr 12, 2010
Modified Apr 12, 2010
Share
FacebookTwitterRedditEmail
Never miss a story
Email address
By submitting your information, you're agreeing to receive communications from New York Public Radio in accordance with our Terms .
By
John Del Signore
Published Apr 12, 2010
Modified Apr 12, 2010
Share
FacebookTwitterRedditEmail
We rely on your support to make local news available to all
Make your contribution now and help Gothamist thrive in 2026. Donate today
Gothamist is funded by sponsors and member donations
Last week we reported that our favorite piece of sandhog hardware, the massive Tunnel Boring Machine [TBM], would soon be put to work digging the Second Avenue subway. Well, the stories are true! Here's a look at the TBM cutter head that will be delivered to the Upper East Side in pieces over the next three weeks. The TBM blade head is 22 feet in diameter and with all its back-up equipment, excavation material haulage system and removal equipment, it will be over 300 feet long and weigh 485 tons, according to a community letter obtained by the Upper Green Side. The MTA says it's so big they'll need to close down part of Second Avenue during delivery, so get your earplugs ready, locals:
All lowering of the TBM and back-up components will take place at the deck opening between 92nd and 91st Streets. A large crane will be located south of this deck opening to perform the lowering operations. Due to the size of the machinery and DOT oversize load restrictions, the delivery of this equipment will need to occur at night between the hours of 11:00 p.m. and 6:00 a.m., on weekdays only.
Lifting the equipment off the trucks and lowering into the launch Box will require up to three lanes of Second Avenue to be closed to traffic for two weeks (April 12 through April 23) and one lane for one week (April 26 through April 30) between the hours of 11:00 pm and 6:00 am. In addition, all lanes will be shut down during the actual pick of the equipment for safety reasons.
Speaking of the Second Avenue subway project, did you know that in the late '60s/early '70s the MTA seriously considered routing the elusive subway line as far east as Avenue C? Second Avenue Sagas recalls the MTA once planned to divert the line east at 17th Street toward Stuyvesant Square (near Stuyvesant Town), under 15th, 14th and 13th Streets to Avenue A, south to Essex Street along East Broadway and across Chatham Square. This Avenue A extension would have cost an additional $57 million. Then the MTA planned an additional loop to Avenue C, between 14th and Houston Streets, for an extra $55 million. By 1974, these plans had gotten so expensive the whole project was shelved.
Below, more on this particular TBM (which has quite an illustrious history!), plus a gorgeous photo of what the entire TBM rig looks like once it's down in the hole with all the "trailing gear" attached.

The TBM "Trailing gear" is a long set of equipment attached to the TBMs, seen here on the 7 line extension. (Courtesy NYC Transit's Twitter)
A spokesperson for the MTA tells us, "The Second Ave Subway TBM was originally manufactured by Robbins about 30 years ago. It is a main gripper, hard-rock machine that has been used on at least 4 other projects and it has been reconditioned to be 'like new.' Schiavone rebuilt the machine in their Newark, N.J., yard where it was assembled and tested, and it has now been disassembled for shipment to the site where it will be reassembled again in the Launch Box.
"The last project that the TBM was used on was the Fall River CSO Project in Fall River, Mass. It was first used to dig the 63rd Street Tunnel in the late '70s. The cutterhead for the TBM has a diameter of 22 ft."
Tagged
digging tunnels
second avenue subway
tbm
tunnel boring machine
John Del Signore
Originally from the Albany area, John Del Signore has called NYC home since 1995. In addition to his thousands of meticulously-crafted bespoke blog posts for Gothamist, his writing has also been published in The Awl, Deadspin, The Nervous Breakdown, and performed at The Brick Theater in Brooklyn.
Read more
Gothamist is funded by sponsors and member donations
Gothamist is funded by sponsors and member donations
MORE news
2 pedestrians killed in Bronx crash after driver ran red light, police say
The NYPD said the investigation is continuing and no one had been arrested Saturday.
By
Brittany Kriegstein
and
Ann Givens
Published Oct 10, 2026
Rain could put a damper on NYC’s long weekend. Here’s when it will clear.
Remnants of Hurricane Isaias could bring more than an inch of rain, gusty winds and even a thunderstorm Sunday before conditions improve Monday.
By
Brittany Kriegstein
News
Rain could put a damper on NYC’s long weekend. Here’s when it will clear.
Remnants of Hurricane Isaias could bring more than an inch of rain, gusty winds and even a thunderstorm Sunday before conditions improve Monday.
By
Brittany Kriegstein
Holy civics! NYC schools' own comic books in the spotlight at Comic Con
By
Jessica Gould
What we know about the ICE shooting in NYC
By
Karen Yi
DSA to Mamdani: Fire NYPD commissioner if ICE doesn't leave NYC
By
Elizabeth Kim
,
Brigid Bergin
and
Ben Feuerherd
Never miss a story
Catch up on the most important headlines with a roundup of essential NYC stories, delivered to your inbox daily.
Sign upEmail address
By submitting your information, you're agreeing to receive communications from New York Public Radio in accordance with our Terms .