Rocky Mountain Power says electrical lines sparked an underground explosion that blew two man hole covers in downtown Salt Lake City on Monday.
The power problems happened at an underground power vault where power lines meet at the intersection of 300 South and 200 East.
"Repair crews determined that a power line connection, or splice, in the underground vault failed," an RMP spokesman stated in a news release Tuesday.
The intersection was closed to cars and foot traffic for about two hours and re-opened shortly after 5 p.m.
A total of 45 businesses and homes in the downtown area lost power Monday afternoon but crews restored power before 5 p.m.
A quick electric arc heated the air in the underground vault and the pressure caused the manhole covers to pop up, the release states. There was smoke from charred insulation, but no sustained fire.
Repairs to the vault will happen in the next few days possibly at night, but should not cause any outages.
Missy Baber, owner of Misc. Boutique said one of her employees saw the man hole covers lift off the ground. A customer who evacuated in the middle of his purchase came back on Tuesday to finalize the sale and say that the covers lifted off the ground with green smoke drifting out as cars and people drove through the intersection.
On Monday, Susy Hadley, co-owner of The Tavernacle piano bar at 201 E. Broadway, said she was at the bar with about four other people when she felt something like an earthquake.
"The lights flickered like we had a power surge, then the building kind of shook and we heard a loud thud," she said. "There was this crazy green smoke coming out of the manhole."
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