Transformer fire at the Hoover Dam quickly extinguished; no injuries or threat to power grid, officials say

Fire from a Tuesday morning transformer explosion at the Hoover Dam was quickly extinguished, caused no injuries and is not a threat to the power grid, according to the Bureau of Reclamation's regional director for the Lower Colorado Region.

Authorities are investigating what caused the fire, the federal Bureau of Reclamation said. In videos posted on social media, a huge plume of black smoke could be seen at the dam.

At approximately 10 a.m. Tuesday morning at "the A5 transformer at Hoover Dam caught fire," according to a statement attributed to Jacklynn L. Gould, the Bureau of Reclamation's regional director for the Lower Colorado Region.

The fire was extinguished 30 minutes later by dam workers and the Hoover fire brigade, the bureau said.

The city of Boulder City, Nevada, posted on its Twitter account that the fire was extinguished before the fire department arrived.

No injuries were reported, either by dam workers or tourists visiting the nearly 90-year-old dam on the border between Nevada and Arizona.

William Herro, 13, of San Francisco, was on a viewing bridge with his parents when he saw the explosion and then heard a “big boom.”

“A ton of black smoke just exploded in the air. It looked almost like a mushroom and then a fire followed,” said Herro, who posted cellphone video of it on TikTok. “I was really surprised and I started filming.”

The postings showed the explosion occurred at a building slightly downstream from the base of the dam.

The dam, which is in the Black Canyon of the Colorado River, generates enough energy each year to serve 1.3 million people, according to its website.

Contributing: Associated Press

This article originally appeared on USA TODAY: Hoover Dam transformer explosion: No injuries; fire put out