It's that time of year again, as New Yorkers gather round the crackling flames to observe the ancient Yuletide tradition. That's right. We're talking about Exploding Manhole Season.
The city's creaky tangle of underground utilities is once again under siege from salty water. The result, as we've seen in the last few days, is an abundance of manhole explosions.
The phenomenon typically happens after a major winter storm, as de-icing salt seeps into the ground, corroding subterranean wires and unleashing gas, which in some cases sparks fires and blows the several-hundred-pound manholes straight into the sky.
Earlier this week, Upper East Side residents were jolted awake at 3 a.m. after a manhole fire lit up the intersection of York Avenue and East 89th Street. “We’re doing a lot of this, these things with this weather," FDNY Battalion Chief Thor Johannessen told CBS-2. "The salt that’s put on the road with the snow that affects the wiring in these manholes."
Here's a helpful graphic from Con Ed—which has 246,000 manholes and service boxes across the five boroughs—that details the process, from (1) Salt to (6) An Explosion.
Neither Con Ed nor FDNY shared details about the number of manhole fires since last week's snow storm. But between 2009 and 2018 there were nearly 4,000 fire department dispatches for manhole explosions, according to The CITY, injuring 57 people, on top of significant amount of property damage and power outages.
Torrential downpours tend to speed up this process, according to Con Ed. The utility recommends that you keep pets away from lampposts, grates, and manhole covers during this "post-storm" period, which seems like good advice for humans as well.
If you spot a smoking manhole, contact Con Ed or the FDNY as soon as possible.
