Wow - three manholes exploded dramatically yesterday afternoon. Flames shot up from manholes between East 69th Street and Second Avenue and East 70th and Third Avenue, causing traffic diversions. Luckily, no one was hurt - just totally spooked, thinking that hell was indeed underground. According to Con Ed, manholes explode when the wires' insulation overheats. Yeesh - we wonder if the manhole covers flipped up or if flames were the main problem. At any rate, Con Ed and the FDNY had to check buildings for carbon monoxide (none had alarming levels).
Check out the How Stuff Works explanation on exploding manholes - has anyone seen if Con Ed is moving towards the slotted manhole covers (they "allow the gas to be released less violently, and also give an early warning to possible explosions") - and our readers' thoughts on some manhole explosions two years ago.
Photograph from 1010WINS