WATCH: Horrifying moment boy is flung from three-storey water slide

A 10-year-old boy is luckily to have escaped without serious injury after he fell off a three-storey water slide and was flung on to concrete in California.

The $43 million "The Wave" water park was open for less than a day when the boy fell off the Emerald Plunge slide onto concrete.

Video has captured the moment the boy fell off the slide. Photo: Bay Area News Group

Video shows the boy getting up after the incident and walking away.

He had skidded several metres across the concrete, leaving him with scratches on his back and visibly shaken.

"I was standing there, he seemed to be shook, but seemed to be okay. Came right up and immediately went into the first aid room and was assessed by staff," Dublin Assistant City Manager Linda Smith told ABC 7.

The boy was sliding down the slide when he was suddenly flung out. Photo: Bay Area News Group

The boy's parents took him to hospital themselves and he has since been released.

The ride is undergoing checks to ensure its safe for users.

Ride rules state that users of slide must have their arms and legs crossed as they descend down the 80-degree drop.

The boy received scratches on his back from sliding across the concrete. Photo: Bay Area News Group

Kron 4 reported that the boy's legs were apart.

This isn't an isolated theme park-related incident.

Last October, four people were killed on the Thunder River Rapids ride at Dreamworld on the Gold Coast after their raft flipped.

And a 10-year-old boy was decapitated when he was thrown out of a waterslide's raft and into the safety netting in Kansas almost a year ago.

Today's top news stories - May 29