The girl - who was reportedly on a school trip at the time - suffered serious injuries when she plunged from the Splash Canyon ride into the 5ft deep water.
She was airlifted to Birmingham Children’s hospital yesterday morning but died shortly after her arrival.
Fellow visitors to the park say they heard crying and screaming coming from the main entrance to the ride, before paramedics arrived on the scene.
“We saw the park golf buggy thing coming down and the guy was shouting, ‘clear the way, clear the way,” Fiona Fletcher, who was at a nearby attraction when the incident unfolded, told BBC.
“By the time we got off the carousel, maybe a minute or two, there were fire engines, ambulances, police cars. ‘the air ambulance was over our heads. It was so fast.’
The park director George Bryan has since told of the staff’s “shock and devastation” at the girl’s death.
“Our thoughts are with her family and friends at this tremendously difficult time,” he said.
Reps took to Twitter to announce that the theme park would be closed tomorrow as a “mark of respect to the family.”
Four people died after the Thunder River Rapids ride malfunctioned at Dreamworld in October last year.
This article originally appeared on New Idea.