If you heard a big "boom" and felt your house or apartment shake around 11:15 tonight (Thursday), you weren't alone. The whole block felt the blast, which was the result of frayed wires under Dean Street between Franklin and Bedford. Explosions like this are actually fairly common, as one of the FDNY guys on the scene informed me. The mains that hold the wires, which sit just below street level, accumulate water, salt, and other street refuse over the years, and eventually this gunk can short-circuit the powerful currents, causing a building-rattling explosion and blasting manhole covers several stories into the air. The one that blew this evening hit a parked car, but thankfully didn't injure any people.
Three fire engines were on the scene within a few minutes to tape off the sidewalks in front of houses that lost power as firemen checked the residences for any potential danger from live current or leaking gases (CO2 is the major potential danger from something like this, as I learned). Plenty of uniformed guys were on hand to calm locals while the fully-geared-up gents checked out the situation. Apparently, this happened a few years back, so most people weren't too freaked out, and things quieted down in a hurry. No danger was found, so the FDNY headed home, with Con Ed promising to come out and fix things up within the hour.