Explosion at Hoover Dam- Key findings

On the morning of Tuesday, July 19, a transformer at the Hoover Dam caught fire, causing an explosion and smoke. 

Hoover Dam, one of the nation's largest hydroelectric facilities, producing a thick cloud of black smoke and flames that were quickly extinguished.

The dam is the largest in the United States and the source for a 2,080-megawatt hydroelectric plant, enough for about 1.3 million households.

No one was hurt in the explosion near the base of the dam and there was no risk to the power grid, as power was still being generated from the powerhouse.

The cause of the fire was under investigation and officials were working to determine the extent of damage to the transformer