EPB spokesperson J. ED Marston says a fault in a power line underground caused Monday’s mini-explosion outside of Chattanooga’s City Hall.

Marston says the explosion was similar to what happened in November when the city hall staff were forced to evacuate. However, he says it did not involve a transformer.  

“It is actually exactly the same thing that we experienced in November,” said Marston. “It was different power line. We went in and replaced the one that happened in November and today we're in the process of replacing the one that happened yesterday, but really it’s really the same thing. It's simply a fault in the line.”

Crews spent Monday making repairs. Marston says crews removed 60 feet of power lines and will replace them on Tuesday. 

Marston says the power line that caught fire is similar to electrical wires in a home. He says they are not easy to inspect and that they are sometimes difficult to detect a fault beforehand.

When we asked if this could happen again, Marston said, “There's a possibility that it could. We're doing maintenance there and we're doing everything we can to make sure it doesn't happen again, but I can't 100 percent guarantee that it won't.”

It's not clear what caused this. Marston says the line was waterproof so the weather is mere speculation so far, but we know it's not normal.

“It's a rare occurrence, but it is the kind of thing that can happen given a system that large enough like ours is,” he said. “The community is in no way at risk. This was a minor incident quickly contained, quickly addressed. I just can't guarantee 100 percent that there's never going to be a problem again because there will be.”