The Occupational Health and Safety Administration office in Tampa, Fla., is investigating the death of 21-year-old Justin Inversso, who was working as a lifeguard at Adventure Island when he was struck by lightning in September.

Inversso was escorting patrons off the 700-foot-high Key West Rapids ride at the waterpark because of an oncoming storm when lightning hit the structure.

He was standing in 2- to 3 feet of water at the time of the lightning strike, according to a report in the Tampa Tribune.

Co-workers administered CPR, but he died at a local hospital.

Busch Gardens and Adventure Island President Jim Dean said in a statement that the incident was the first of its kind since the waterpark opened in 1980.