After an impromptu tour of the L train tunnel last month and three weeks of consultations with engineering professors from Columbia and Cornell Universities, Gov. Andrew Cuomo ordered the MTA to cancel the impending 15-month shutdown of the L train tunnel between Brooklyn and Manhattan. Instead, the scope of the necessary repairs will seemingly be reduced, and per Cuomo’s orders, the remaining work will proceed on a 15-20 month schedule that maintains regular weekday L train service and relies on single-tracking (and 20-minute headways) during nights and throughout the weekend.
It’s a drastic shift in scheduling and scope, and while tentatively welcomed by Brooklyn residents on the precipice of a 15-month transit nightmare, it threw years of careful planning by the MTA and NYC DOT as well as tireless work by advocates fighting for a transit-first redesign of New York City streets into disarray, all just three months before the shutdown was to begin. At its core, the move is quintessential King Cuomo. Sounding very Trumpian, Cuomo, who ended his press conference by saying, “No, I am not in charge of the MTA,” spent over an hour on Thursday touting his “panel of the best experts we could find” and came up with a plan in three weeks that remains underdeveloped and untested. At best, it will kick the can down the road; at worst, it will fail, costing precious time and even more money. No matter what, everyone involved with the L train shutdown I’ve spoken with today agreed that at some point in the near future, whether it be 10 or 20 or 30 years down the road, the MTA will have to rebuild the L train’s 14th Street tunnel.
Cuomo’s plan isn’t well developed. The MTA had published hundreds, if not thousands, of pages of studies, presentations, reports and analysis regarding the L train shutdown. The governor has hosted one rambling, long press conference and issued a thousand-word press release on his new plan. The governor who has spent years sucking up the oxygen in the room claiming he doesn’t control the MTA swooped in at the last minute to unilaterally impose new plans on the MTA. He did this without consulting anyone involved in planning the work or the community groups on the ground working to ensure a mitigation as smooth as possible. This is Cuomo, in control, with only his own ideas and no one else’s guiding him.
We don’t know when the work will start in earnest, what the cost will be, how it’s being scoped, or what mitigation is required. We don’t know what’s to become of plans for a 14th St. transitway, bike lanes throughout Manhattan or a bus bridge over the Williamsburg Bridge, all of which had significant value to a transit-oriented future for NYC in their own rights. We know outlines and aspirations, and I’ll try to distill them down in this post, raising questions at the end. There’s more to be said over the next few days as I arrange my thoughts on this topic, but it’s fair to say Cuomo, without any community outreach and no warning to the MTA Board, changed the conversation in one fell swoop today. Whether it’s for the better remains to be seen.
What is Governor Cuomo’s new plan to repair the L train tunnel?
At a high level, Cuomo’s plans appear simple because the details haven’t been fleshed out yet, and the main thrust of the work involves the ducts. The bulk of the work necessitating a full-time shutdown of the L train focused around the so-called bench wall that carries cables through the tunnel and serves as an emergency exit pathway. Because of saltwater intrusion, the MTA planned to chip out and rebuild the entirety of four bench walls in the two tunnels. Instead, under the new approach, the MTA will use a rack wall to run new cabling and other required systems through the Canarsie Tunnel above ground level. This is generally how cables are fed through tunnels in other cities, and the bench wall remains a relic of the early days of NYC subway construction.
Mary Boyce, Dean of Engineering at Columbia University and one of Cuomo’s experts, spoke at length about the plan to “rack” cables on the side of the tunnel while abandoning old cables in the benchwall and leaving the benchwall in place unless structurally unsound.
We are recommending that the cables be wrapped. So the majority of the cables, the power cables, the communications cables, control cables that power the train, the pump, the fans, that these be wrapped along the walls on one side. This leaves the other walls free for egress and access. We’ve looked at many challenges with actually doing this and different ways to actually wrap these cables, and we have found that it does indeed seem to be possible. We will also place the negative return on the track bed. So what this is essentially doing is decoupling the cable system from the benchwall. These are two different functions. We are able to execute all of the functions of the cables without them being in the benchwalls. So we do not give up or sacrifice any functionality of the system.
An important thing that we have to address is making sure that the fire retardancy is still possible for these cables, so the cables must be jacketed and they’re jacketed with a low smoke zero-halogen fireproof material. This is a proven technology, it has been used in these newer designs and newer modern tunnel systems. It’s also used in aircraft. So what happens with these jacket cables is that, yes there’s some sort of thermoplastic or thermostat, but they have an inorganic filler so they char in the presence of heat or fire, so there’s no outgassing and they actually become even better insulated. So this is another key feature of being able to wrap these cables on the wall and not embed them in the benchwall. This also very importantly means that we can abandon all the old cables in the benchwall. We do not need to remove them and replace them, we just leave them there. So if a benchwall is still structurally sound, we do not need to destroy it, remove the cables and rebuild it. This is a very key factor, okay, because it significantly reduces demolition and construction, and we feel probably has a cost implication as well.
And what about the benchwall, which serves not only as a cabling conduit but as an emergency walkway in the event a tunnel evacuation is required? Lance Collins, Dean of Engineering at Cornell University, offered his take on this vital piece of tunnel infrastructure:
There’s benchwall, that’s going to, in some sense, be stable and remain. There’s benchwall that’s been compromised to some degree, but not significantly. That we think we can reinforce using something called ‘fiber reinforced polymer’ – so it’s essentially a mixture of epoxy and fiber to wrap around. This will last for decades, for a long period of time. It’s not a quick fix. It’s technology that’s been widely used in bridges, in buildings, so we’re simply applying it in a very different application here.
And then there’s a third category which is benchwall that really is just not structurally sound that has to ultimately be demolished and removed. Then the question becomes, how do we know what’s what and so we’re going to use a state-of-the-art ultrasound technology to evaluate the entire length of the benchwall and figure out, you know, which parts of the benchwall are in which categories and act accordingly to either leave it as it is or to reinforce it as needed, or remove it as needed. And what’s important is that the benchwall is really serving the primary purposes – it’s back to its primary purpose which is access and egress. It’s no longer serving any role with respect to the cabling, so that’s the only element we have to ensure in terms of functionality that we have retained.
To study this retained benchwall that the MTA had planned, until yesterday, to fully replace, Cuomo’s team will implement fiber optic sensors. These sensors, Collins said, “will be able to pick up small changes and deformations in the benchwall in advance of failure. So that if there were something that eventually is going to fail, we will know that in advance and be able to send in a team to go in and do whatever is necessary: reinforce that section as needed in advance of the actual failure.” The new walkway, Collins stated, will be “just fiber glass, steel,” promising a “relatively simple installation.”
Why didn’t anyone come up with this sooner?
This seems to be one of the key questions on everyone’s minds. Related is the question about Cuomo’s involvement: Why didn’t the governor address this issue years ago? Either he was asleep at the wheel or the MTA was asleep at the wheel. Either he’s imposing something upon the MTA that its in-house team does not feel will adequately address the scope of work required to repair the L train for decades (as the MTA successfully did with the Montague St. tunnel) or Cuomo is seeking quick political wins to gain positive coverage while kicking the real can down the road by a decade or two when he will, as he loves to remind audiences, be dead. I don’t yet have a good answer here, but I do know a lot of people inside the MTA are very unhappy about the governor’s approach. (For what it’s worth, John O’Grady, whom I interviewed at the Transit Museum back in 2015 retired or was pushed out of Capital Construction last week.)
What’s the actual state of the L train tunnel?
Now we’re getting into the tricky questions. For years, everything the MTA has said about the L train tunnel led to a need for a rebuild. The agency quickly wiped the L train shutdown pages from its website on Thursday, but both the Google Cache and Wayback Machine never forget. The following image highlighted the need to replace more than just the duct banks:
I’d also urge you to take a look at this video of the Canarsie Tube the MTA posted in 2016 (embedded below). Particularly, note the bench wall at the 57-second mark and the concrete between the railway ties at around the 2:59 mark. In multiple places, you can spot brackets holding up the bench wall, and those who were close to the original assessments of the Canarsie Tunnel tell me that Cuomo’s move to use polymer will result in more work and more disruptions in a few decades rather than a rebuild a la Montague which would have ensured five decades of continued use.
For his part, Cuomo promised the tunnel was now perfectly OK. “The major structural elements of the tunnel are fine. There is no structural integrity issue for the tunnel itself. So people worry, is the tunnel going to have any significant issues? No. The structure of the tunnel is fine.”
The videos seem to tell a different story, and it’s not exactly clear how the MTA plans to address trackbed repair – the other major driver of a full-time shutdown. Boyce, in her comments, hedged. “The upgrades to the pump system and the rail can occur in tandem, she said. “These were planned and they can occur in tandem with the cable and benchwall work. So there’s no compromising on those upgrades. And we see a dramatic reduction in what we refer to as the non-value-added project scope. So we don’t reduce the scope, but we eliminate those parts of the scope that had no value.”
How will mitigation proceed?
Without a better sense of scope, it’s premature to know what mitigation is required or when. Most politicians and advocates have bemoaned Cuomo’s attempts at circumventing a careful process and urge the MTA to involve all community groups in presenting updated options, including guaranteeing sufficient mitigation plans. Interim MTA Chair Fernando Ferrer noted that G, M and 7 trains will still see added service (though the 7 train upgrades are due primarily to CBTC).
As I mentioned, the future of the other mitigation work is foggy. This is worth a separate post later on so I’ll come back to this.
How long will this take?
Who knows?! Cuomo kept saying his experts think the work can be completed with 15-20 months of 20-headways every night and throughout the weekend, but he wouldn’t guarantee it. “It’s a silly question to ask am I going to promise on a construction schedule for an agency,” he said. So there you have it: No promises this will be finished in the same amount of time as the planned shutdown. We don’t know how much it will cost either, other than “less than a full shutdown.”
What about those other projects?
The MTA was planning to piggyback significant work onto the L train shutdown. Without trains running constantly, the agency could build a new entrance to the 1st Ave. station at Ave. A, replete with elevators, add ADA accessibility features to other stations along the L in Manhattan, widen and rebuild staircases at Union Square, and implement badly-needed power capacity upgrades to ensure more trains could run per hour. The agency says all of these projects will continue, but it’s not clear how Cuomo’s meddling interferes with this work. Can these projects be finished without substantial disruption to the limited service? Will it take longer than 15-20 months to complete this work? And how can the agency close staircases at Union Square while operating heavily overburdened L service? These are questions Cuomo and the MTA could not answer on Thursday but must be addressed soon.
Should we trust anyone here?
Not in the least. Although the MTA earned the benefit of the doubt by rebuilding the Montague St. Tunnel and has a good track record on completing Sandy-related repairs, the agency has not been able to manage large-scale projects or implement outside-the-box thinking. The governor, meanwhile, has shown no willingness to participate in careful and deliberate community outreach processes, and despite his statement yesterday that “I educated myself to the best extent possible,” the governor has spent barely a month on the L train shutdown. His past record of meddling with transit led to cost overruns on the Second Ave. Subway and a New Tappan Zee Bridge without the transit options advocates desired (or a clear sense of costs). I could spend another 600 words writing on this topic, but there is, simply put, little reason to trust this process right now without substantially more detailed answers to a variety of questions.
This too is an open question. To step in at the last minute with a radically different approach based only on the ideas of a few consultants is very much in line with Cuomo’s governing strategy, but as I keep saying, it leaves much to be desired from a procedural perspective. I’ll try to explore this further as well.
This post is heavy on the skepticism and for good reason, and I didn’t even get to discuss Andy Byford’s apparent resigned acceptance of this approach and his near-total absence from today’s press conference. There’s just so many moving parts here.
Despite the belief that NYC DOT’s mitigation plan wasn’t going to be sufficient for Day One, the MTA and DOT had spent years collaborating on plans for a very disruptive shutdown, working to get political buy-in at every level of the community. Cuomo has shred every ounce of goodwill that may have existed for a project that we just can’t assess yet. Maybe this is the way to reform MTA thinking and MTA practices. Maybe this will work. But maybe this is Cuomo shooting for the stars (or at least 1600 Pennsylvania Avenue), and maybe we shouldn’t be rushing into vital infrastructure repairs using unproven technologies without testing them on non-critical infrastructure first. Maybe in 10 years or 15 years, we’ll be back here facing optical sensors no one at the MTA bothered to maintain and a collapsing bench wall that leads to a derailment in L train service (as happened to the G train).
Maybe we’ll get to go through this all over again when someone else is Governor. One way or another, Gov. Cuomo, in trying to be the hero, showed extreme disregard for the travails of Brooklyn and Manhattan and the communities gearing up for the L train shutdown. It might be better this way; it might be worse. We all deserve to know more about the details of the plan, how it will work, and why Cuomo waited so long (or the MTA never followed this route) in the first place. Too much time and effort went into considerable deliberations for Cuomo to impose his will at the last minute without careful planning, outreach and analysis.