Invisible danger – shock drowning

But, there's a hidden danger that lurks under the surface of freshwater lakes, called electric shock drowning.

Electric shock drowning happens when power boats and boat houses leak electricity into fresh water, thereby electrocuting swimmers.

The Canadian Safe Boating Council says there are a number of deaths from electric shock drowning each year.

The council's director Michael Vollmer says a lot of the cases of death from electric shock drowning are not reported because the cause of death is typically considered drowning.

He says "somebody will be swimming along and then all of a sudden they'll just stop swimming and sink to the bottom."

"You look at that and you say, 'Oh, they drowned'," says Vollmer.

"Well, the reason they sank to the bottom is because their heart stopped beating."

Brian Patterson, president of the Ontario Safety League, said people need to know that house wiring is not the same as boat wiring.

"Having uncle Joe or cousin Bob wiring up your boathouse when they are not electricians and can't really certify what they're doing, they may do their best job, but their best jobs could be deadly," Patterson said.

He said such deaths can be prevented by placing leakage interrupters — which are not mandatory — on boats.