BOSTON (WHDH) - Flickering lights and smoke billowing from a manhole in Boston’s Back Bay led to a series of explosions Tuesday that knocked out power in the area and left behind a foul odor, according to witnesses.
“A lot of the smoke you can still smell it in the building actually,” said Alexis Comeau, who manages a building in the area.
Eversource said a cable failure caused smoke to build up underground and eventually burst. Though the explosions caused a scare for residents, Eversource said a recent innovation helped diffuse the damage.
7 Investigates got an exclusive look at the city’s new manhole covers last year. The covers are designed with hooks and a lip that allows them to lift up to release pressure, then safely drop back down. A demonstration showed the cover rise only a few inches, so hot air can rush out.
“The cover released the energy and stayed right in place,” said Doug Foley, an Eversource worker. “Without a latch, with a right amount of energy, that cover could come dislodged and come off the casting.”
7 Investigates also got an exclusive look underground when Eversource crews showed chambers packed with electrical wiring that power businesses, streetlights, and homes. Over time, crews say weather and wear can break down those cables and the lines can short out. When that happens, the air in the chambers heats up and expands, and pressure builds up to a point where something has to give.
Residents said although they were rattled by the explosion, they’re grateful no one was hurt.
“I’m glad everyone’s okay,” said Helaine Gulergun, a business owner. “We’re all very lucky.”
Eversource said they have replaced 98 percent of the manhole covers in Boston, and nearly two-thirds of their covers in all of Massachusetts. The company said winter weather was most likely what contributed to this cable short.
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