Saturday, March 27, 2010

The Starter Tunnels

The MTA sent their staff photographer Patrick Cashin underground on Friday to capture a set of images of the on-going work that is taking place inside the Second Avenue subway TBM launch box.

Here are a few of his images, courtesy of the MTA.

Patrick J. Cashin/MTA - 3/26/10

An Update - 4/2/10
The MTA just provided me with a high-resolution copy of this image. Left-click on the image to see an amazingly detailed view of the inside the TBM launch box.

The photographer is standing on the floor of the launch box - about 60 feet below street level - and his camera is pointed south.

The two holes that you see are the starter tunnels for the new Second Avenue subway line. These two tunnels will be blasted to a depth of about 40-50 feet and then the tunnel boring machine will be set up to bore the actual tunnels down to 63rd Street.

If you look closely at the right and left walls you can see where the bedrock ends and the concrete secant walls of the launch box begin. All of the bedrock that was present at the south end of the launch box was removed using controlled blasting over the past few months.

After the tunneling is finished (in June 2011, according to the current schedule) they will turn this cavern into the new 96th Street station.

Patrick J. Cashin/MTA - 3/26/10

The photographer here is standing (approx.) under 92nd Street. (The open hole in the image is in front of Delizia's Ristorante & Pizzeria at 92nd Street and Second Avenue.)

It looks like the workers here are preparing for the next blast by drilling holes in the rock for the explosives. (The blast on 3/26 took place at 7:50 PM.)

If you look at the top of this picture you see the road decking that covers Second Avenue between 92nd and 95th Streets. You can also see some of the utility lines (water, gas, electric, telephone, etc.) that have been suspended from the decking.

Patrick J. Cashin/MTA - 3/26/10

Patrick J. Cashin/MTA - 3/26/10

Patrick J. Cashin/MTA - 3/26/10

In this image the photographer has turned himself around so that he's facing north.

The 36" round steel struts that are shown in this image, and the one below, act to counter the forces that the ground and buildings (outside the box) exert on the walls.

The wall at the far end of the launch box is just south of 95th Street - 3 city block away!

Patrick J. Cashin/MTA - 3/26/10

When you look at these pictures you begin to realize just how much work has taken place on this project over the past 3 years.

Every last shovelful of dirt, rock and muck in this enormous hole has been brought to the surface by these workers and hauled away by truck.

About a dozen additional images taken by Mr. Cashin are available on the MTA's Official Facebook page.


About a week ago the MTA mailed out letters to a number of tenants on Second Avenue with the news that they would need to temporarily relocate due to work that needed to be performed to reinforce the integrity of their building, in advance of upcoming work.

This story was first broken by the real estate magazine, The Real Deal, in their piece "UES Residents Ousted Due to Second Avenue Subway Construction" on Monday, March 22nd.

By Tuesday morning, the NY Post, The Daily News, and amNY ran articles on the story, and most of the local TV stations were working on pieces for the evening news. (I was contacted by two of the TV stations.)

Note: Links to a few of these news articles and videos can be found at the end of this posting.

Interested viewers can find a copy of the letter that the MTA sent to residents at 1873 Second Avenue below:

Letter from MTA Capital Construction to a tenant at 1873 Second Avenue - 3/19/10

Various media sources reported that the affected apartments are located at 1873 Second Avenue and the five walk-ups between 1821 and 1829 Second Avenue, as shown in the diagram below.

Courtesy New York Post
"2nd Ave. Subway dig sends tenants packin' " - 3/24/10

94th Street, near the SE corner - looking NW

This image shows the west side of Second Avenue between 94th and 95th Streets. The affected buildings, from 1821 - 1829 Second Avenue, are outlined in blue.

btw. 1827 and 1829 Second Avenue - looking straight up

If you look closely at this image you can see some of the instruments that have been mounted on this building by the MTA's contractors - including a number of retroreflectors. These instruments allow the contractors to monitor the stability of the building in real-time.

Further information on how retroreflectors are used on this project can be found on my earlier posting "Retroreflectors Everywhere".

97th Street & Second Avenue - looking SW

This is the affected building at 1873 Second Avenue - which also has numerous instruments mounted on its facade and on the north and south walls.

The good news out of all this is that the affected tenants will live rent free during the period that they are relocated.

Also, if the MTA wants to make this as painless as possible they could offer accommodation to the affected people at The Marmara Manhattan Hotel (which is a long-term stay hotel) located at the corner of 94th Street and Second Avenue.


btw. 92nd & 93rd Streets - looking NE

This image and the one that follows show the vertical conveyor that is still under construction on the east side of 2nd Avenue between 92nd & 93rd Streets.

The vertical conveyor system on this project is manufactured by the Finish company Metso.

near the SE corner of 93rd Street - looking SW

92nd Street - looking NE

A picture of various wheelbarrows on the work site.


Here's a summary of the blasting that occurred at the TBM launch box location in the evening during the past week:

Monday, 3/22 - 1 blast at 8:15 p.m. and a 2nd blast at 8:50 p.m.

Tuesday 3/23 - 1 blast at 8:03 p.m.

Wednesday 3/24 - 1 blast at 8:30 p.m.

Thursday 3/25 - 1 blast at 8:05 p.m.

Friday 3/26 - 1 blast at 7:50 p.m.

On Friday 3/26/10, Community Board 8 passed along a notice (via e-mail) from the MTA regarding the blasting of the starter tunnels. Part of the text of this notice is shown below:
"Controlled blasting to excavate two starter tunnels at the south end of the Second Avenue Subway Launch Box, in preparation for the arrival of the Tunnel Boring Machine, began in early March and is scheduled to be completed by mid-April. Controlled blasting is a well established excavation technique that has been used at many of our projects in Manhattan.

You may have noticed that the blasts are slightly louder and longer in duration compared to the launch box blasts and this is due to the confined area of the starter tunnels. In addition, because of the time it takes to prepare for each blast, the blasts are occurring later in the day at approximately 8 PM. Note, blasting is permitted to take place during the approved Second Ave Subway working hours of 7 AM to 10 PM, although, every effort has been made to limit blasting to daylight hours."

For reasons that I cannot explain, this notice was circulated a few weeks after the blasting of the starter tunnels began. I could imagine that the notice is being released now because of the number of people that are calling to inquire about the starter tunnel blasting.

As a resident of the area, I must say that I was more than a little surprised with the statement that the blasts would be "slightly louder" than the blasts that occurred earlier.

I've heard many of the blasts over the past few months and the blasting that is going on now is not "slightly" louder; it is considerably louder than the earlier blasts. (Some I'm sure will say that this is an understatement on my part.)

Anyone wishing to see how loud these blasts are should watch the video that I made of the starter tunnel blast that took place on 3/19/10. (FYI - I've recently noticed that others have now posted their own videos of various 2nd Avenue subway starter tunnel blasts on the YouTube web site.)

One last point on the blasting . . .

I can't prove it, but my feeling is that the blasting that is taking place now, for the starter tunnels, is about as loud as the sound that is made when a bolt of lighting strikes very near to your building. i.e. when the sound made by the thunder comes right at the same time as the flash. The only difference is that sound of these blasts goes on for a few seconds and the sound of the thunder fades away rather fast.

The blasting is expected to be over in a few weeks and then hopefully those of us who live in the 90s will not have to hear the sound of the blasting whistle again on this project.


Here's a listing of the recent additions
to the right-hand column of The Launch Box

UES residents ousted due to Second Avenue Subway construction
The Real Deal - 3/22/10

"2nd Ave. Subway dig sends tenants packin' "
By Rebecca Harshbarger and Tom Namako
NY Post - 3/23/10

"MTA's construction of 2nd Ave. subway forcing New Yorkers from six buildings to move out"
By Nikki Dowling and Oren Yaniv
NY Daily News - 3/23/10

Living in the Upper East Side’s blast zone

2nd. Ave. Sagas - 3/23/10

"Subway work impacts apartment residents" (2:26)
By Tim Fleisher
WABC-TV/DT New York - 3/23/10

"2nd Ave Subway Construction Forcing out Tenants" (1:51)
By Adam Siff
WNBC-TV - 3/23/10

"Second Avenue Subway Problems" (2:07)
By Ti-Hua Chang - 3/23/10

"Serrano Outraged at Ongoing Disruptions to Second Avenue Residents and Businesses"
Office of Senator José M. Serrano (press release) - 3/24/10

The futureNYCSubway: 2nd Avenue Subway History
By Andrew Lynch
Vanshnookenraggen (a blog) - 3/24/10
An excellent overview of the history of the project.


A Footnote

It has occurred to me that it is not that easy to figure out how to contact me via this blog. (Until now the only way to do this was to click on the "View my complete profile" tab and then click on the "email" contact tab - or post a comment.)

To make it easier I've decided to post an e-mail address on the blog. This address is TheLaunchBoxBLOG AT (I didn't use the @ sign here in an effort to reduce the chance that this address will attract spam e-mail.)

If you wish to contact me with feedback, comments, a tips, suggestions, etc. please go ahead and drop me a note.

I give you my word that any correspondence that I receive will remain completely confidential.


1 comment:

jmp said...

The MTA can't offer space at the Marmara, because the Marmara is full. They've got a contract with Cirque du Soleil to house all of Cirque's performers while they're performing on Randall's Island.