While you were sleeping, the MTA has terror-proofed its subway tunnels and bridges, according to a report in The Post. Transit reporter Tom Namako spills the beans on a $250-million plan to shore up the ten subway tunnels that pass under the East River.
Since 2004, agency contractors have been lining subway tubes — especially the 10 that run under the East River — with high-impact-bearing metal that would prevent collapse or massive flooding in the case of a terrorist attack, multiple sources said. And in the more shallow tunnels that aren’t fully dug into rock, like the F line that connects 63rd Street to Roosevelt Island, workers dropped massive slabs of rock and concrete on the riverbed to prevent disaster, the sources said.
The MTA’s security makeover isn’t limited to tunnels. The agency’s seven bridges are being “hardened” with plates and “collars” on cables that can resist a blast, sources said. The agency originally planned to use a lightweight, blast-resistant material to ring the tunnels — but sources said that various types of materials have been used.
One of more complicated tasks was determining which parts of the aged tunnels were bored deep into rock and which parts come close to the surface. “That presents several issues. With some tunnels, there’s a point where they come out to the surface and there’s different vulnerability there than with tunnels in bedrock,” one source said.
The work, was deemed 93 percent completed in January, has come in at $22 million over budget. “A lot has been done in regards to hardening, and that work continues to move forward,” MTA spokesman Kevin Ortiz said to The Post.
Namako’s report follows an earlier revelation that the Port Authority has spent $600 million to to ring PATH tunnels in steel. Reported The Post, “Defense contractors — toiling in the cloak of darkness — are installing reinforced metal plates along the interior walls of the tunnels, and massive flood-prevention gates are being erected at either end of the two main lines that run from the World Trade Center and the West Village to Jersey City, sources said. The flood gates are designed to close off one or more tubes should water come surging in. That would protect other parts of the PATH system and its riders, which number about 250,000 a day.”
The PATH project, funded in part by the Department of Homeland Security and some stimulus dollars, carries a higher price tag than the MTA’s own security initiatives, but it has come in at nearly $300 million under budget. “The safety of our customers is the Port Authority’s highest priority, which is why we have spent over $5 billion since 9/11 upgrading the security systems at our facilities,” PATH COO Ernesto Butcher said. “Hardening our PATH rail tunnels is one example of that effort.”
8 comments
Are there any pictures of what these tunnels look like on the bed of the river or is the water too dark & murky? I’ve always been really curious about them.
That’s a good question, and I’m honestly not sure if those photos exists. The MTA is very careful from a security standpoint of the tunnels. People can’t access them freely and I doubt they’re keen on allowing photographers into them.
I doubt there’s much to see. Most of the tunnels are completely under the riverbed.
While the $300 million dollar under budget figure is nice. In percentage terms the $22M over budget figure isn’t that enormous. I mean it’s not great. But considering how other things work, it’s not bad.
The majority of NYCT’s 14 subaqueous tunnels lie below the river bed with sufficient cover between the top of the crown (as tops of tunnels are called) and the river bottom. Because they lie mostly within mud, silt, and sedimentary deposits, they were built using the shield driven method, i.e. sandhogs working within shielded tubes under compressed air pressure, with an open face to actually perform the excavation. This is a very simplified description; the specific methods varied for each tunnel due to geologic conditions and depth, as well as instances where larger obstructions such as glacial till and rock were encountered, which were surmounted by mining and blasting. Following excavation and initial support, cast iron rings were installed, and finally encased in concrete. The Pennsylvania RR tunnels under the Hudson and East Rivers, as well as all of the region’s underwater vehicular tunnels were constructed in this manner. So were the PATH tunnels, although in many areas the cast iron rings were not encased, thus making the current hardening project all the more critically important. Because of the great risks involved, shield driven tunnels built under compressed air are no longer considered to be a viable method for most rail tunnel construction today – the modern Tunnel Boring Machine and its specific variants for differing geologic conditions have mostly eliminated the need for compressed air tunneling.
Three sets of the subaqueous NYCT tunnels were actually prefabricated on shore, with a combination of steel and concrete, floated over to their respective locations and then sunken into prepared trenches, with connections made at the shore ends to establish links to the land tunnels. The modern description of this type is the immersed tunnel method. Again, this is a simplified description; two of the tunnels built as part of the early IRT were done this way and were pioneering structures for their time; the third, more recent (relatively speaking) is actually the last subaqueous subway tunnel built in NYC. The immersed tunnel method is widely used around the world today.
Although I am going to refrain from saying more, this information is readily available in the public domain and is described in greater detail in most of the better books on subway history and construction that are out there, including information on the individual tunnel names, types, length, and other particular details, along with construction photos. Many of the better subway history websites have the same information as well. A few of the books that were published to coincide with the subway centennial in 2004 contain great photos of the subaqueous tunnels while they were under construction.
“A $250-million plan to shore up the ten subway tunnels that pass under the East River. The work, was deemed 93 percent completed in January, has come in at $22 million over budget.”
That’s just 8.8% over budget and actually finished? Damn, can we hire those folks to do the rest of the capital plan?
I’m not a big fan of terror paranoia, but this seems pretty sensible and may even extend the life of these tunnels. Just don’t let the police harass subway enthusiasts.