MONTREAL—A day after an 18-month-old toddler drowned in a residential pool in Laval’s Ste-Rose district—Quebec’s 41 drowning so far in 2012, a near record pace—concerns about swimming safety are growing louder.

A swimming instructor, Regent LaCoursiere, says he has taught three million children to swim during his 60 years in the pool.

While parents should install fences and other physical barriers around pools, LaCoursiere feels that swimming instructions should start when children are much younger, as early as six weeks.

“You need to supervise them at all times. Even if you’ve got a gate around your pool and even if you’ve got a lifejacket, you can hit your head,” said LaCoursiere.

“Something can happen. You need to watch them at all times. You can’t take your eyes off them for one minute.”

LaCoursiere recommends flotation devices to help children when they first start swimming.