Chlorine leak at Ottawa-area water park highlights chemical dangers at swimming pools

In a hot summer like this one, swimming pools and water parks are favoured refuges from the heat.

So a spate of spills of potentially deadly chlorine, used as a pool disinfectant, has got to be worrying for families looking for a cool place to relax.

The latest incident occurred this week at the Calypso Waterpark near Ottawa, where 13 children were hospitalized by a chlorine leak at its wave pool Tuesday.

The Ottawa Citizen reported the park's public relations firm issued a statement Wednesday saying the incident was triggered by a 15-minute maintenance shutdown of the pool's filtration system without shutting down its chlorine pumps. That caused a buildup of chlorine, which turned into a gas when it reached the pool when the system was restarted.

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The affected children were hospitalized after apparently inhaling the gas, which triggered vomiting, choking and foaming at the mouth, the Citizen said.

"Calypso Theme Waterpark team extends its deepest apologies for the incident that occurred in the early afternoon yesterday," the park's statement read.

Public health official Nicole Laplante told the Citizen that the pool's water was tested after the incident and found to be within acceptable limits.

Calypso's statement said the affected children were all in an area of the pool where several outlets from the water-filtration system were located.

"It took our breath away," Nick Beaudoin, who was in the pool with his nephews, aged six and eight, told the Citizen "We just started choking on clear air. I grabbed them both under my arms and tried to cover their mouths."

Calypso apparently was already under investigation by the Ontario Technical Standards and Safety Authority, which oversees amusement parks, after an accident on its waterslide that sent two men to hospital last month.

"Since then we've had a number of other complaints come in," authority spokesman Wilson Lee, told the Citizen. "We're now reviewing Calypso's operating history a bit more thoroughly."

The agency's jurisdiction doesn't cover safety standards at the wave pool, Lee said.

"That's not to say it won't be factored in," he said. "If we're reviewing Calypso's operating procedures, we will be taking a broad perspective and that could certainly be a consideration. But it's not something we're specifically looking at."

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The incident at Calypso follows a chlorine spill at Calgary's Trico Recreation Centre last month that forced evacuation of the building and sent one person to hospital.

Fire Chief Don Howard told CBC News staff were doing routine maintenance early in the morning when they noticed a leak.

"They were draining out their Jacuzzi tub that's in there, the hot tub," Howard said. "They started getting high chlorine readings, there is chlorine mixed in with the pools to start with."

Six employees were forced out of the building and one was taken to hospital for observation. There were no members of the public in the rec centre at that time.

A July 12 chlorine spill at a public pool in St. Catharines, Ont., which sent 12 people to hospital, has triggered a potential class-action law suit, the St. Catharines Standard reported.

A law firm has filed suit against the city and the firm that supplied the pool chemicals on behalf of a St. Catharines resident and his daughter who were injured by the spill.

The suit alleged a service technician poured chlorine into a tank containing muratic acid, creating a cloud of toxic gas that affected up to 200 people.

In northern British Columbia, 70 people, including 40 young competitive swimmers attending a regional meet, were sent to hospital after chlorine gas flooded into the Williams Lake rec centre's pool area last February.

Local hospital spokeswoman Allison Ruault told the Vancouver Sun most victims had their eyes flushed with water and took showers to get rid of the chlorine.

"There was a lot of people as well that required oxygen," Ruault said.

Officials traced the leak to a failed vacuum regulator in the 30-year-old pool's automated chlorination system, CBC News reported.