A broken water pump and an electrical problem with a chemical dispenser apparently combined to push too much chlorine into the wave pool at a Sacramento water park, sending 20 people to the hospital, a county official said Tuesday.
At least 15 of the people who suffered burning lungs or irritated eyes in the incident Monday afternoon have been released from five area hospitals. The conditions of the other five people could not be determined.
The Raging Waters park reopened Tuesday, but the 500,000-gallon "Breaker Beach" wave pool stayed shut while inspectors investigated.
A county worker found preliminary evidence that two problems combined to cause the chemical exposure, said Colleen Maitoza, a supervisor with Sacramento County's environmental management department.
One of the two pumps that circulate water through the filtration system for the pool broke down Monday, reducing the flow, she said. Normally, that failure would cut off a dispenser that adds a liquid chlorine compound to the pool, but the chlorine pump kept pushing more of the caustic chemical into the system, she said.
"It's not clear if that was a wiring problem," she said. The chlorine pump was plugged in with an extension cord and it was unclear if the outlet to which it was connected had a safety mechanism connected with the water pumps, she said.
Joe Pinell, a spokesman for the park, confirmed there had been a malfunction and said the wave pool would remain closed during the investigation. The company deeply regrets the incident, he said.
"Our No. 1 priority is the safety of our guests," Pinell said in a prepared statement. He would not comment on the county inspection.
John Rogers, chief of Sacramento County's Environmental Health Division, said a routine July 21 inspection found two minor problems with the wave pool but none with the chemical system. The county office oversees health and safety at public pools, including the operation and maintenance of equipment.
The California Division of Occupational Safety and Health, known as Cal/OSHA, opened two investigations of the park. One focused on public safety and the other on safety of employees.
Three park employees and nine children were among those transported to the hospital Monday.
A review of Cal/OSHA records showed one minor violation in the past 10 years at the Raging Waters location in Sacramento, for lacking written materials on how to prevent heat-related illnesses.
Another Raging Waters park in San Dimas had two violations in 10 years, both involving posting of required notices on equipment. A third park in San Jose showed no violations.