With summertime in full swing and sweltering heatwaves across the country, safety experts are reminding Canadians to remain safe in the water.

Mid-July is often one of the deadliest times of the year for drownings in Canada, and several recent deaths have underscored the importance of being cautious while swimming.

A 17-year-old boy is presumed dead after he disappeared Wednesday while swimming with friends in southern Manitoba, and an 18-year-old male drowned in the resort village of Port Stanley, Ont. on Thursday afternoon when the wind picked up and swimming conditions became challenging.

Drownings in Canada have remained tragically common in recent years, with 308 drownings in 2014 and 313 in 2015, according to the most recent report.

“People are flocking to the waterways to enjoy them, but tragically, they’re not using caution they need to and understanding the dangers that are still present,” said Carl Shier of the Lifesaving Society of Manitoba.

Cases of drowning among children have become less common in recent years, a fact that is often linked to increased water safety awareness. But baby boomers aged 50 to 64 and those 65 and older remain at heightened risk of drowning, possibly due to the popularity of boating.

Regardless, young people have the highest number of drownings year after year. Between 2009 and 2013, an average of 44 young people between 20 and 24 drowned each year.

Experts say that youth swimmers -- particularly young males -- are more likely to mix alcohol with swimming, and they also more commonly venture into the water after dark.

“All those things combined always put young people, and predominately males, as the highest category group for drowning,” Shier said.

More than 80 per cent of all Canadian drownings in the sample period occurred among men.

From a provincial perspective, Ontario had the most unintentional water-related deaths in 2014 and 2015, followed by B.C. and then Quebec, according to the Canadian Drowning Report.

Swimmers looking to stay safe on the water are advised to wear a lifejacket while boating, return to shore at dusk and never go swimming alone.

With a report from CTV’s Manitoba Bureau Chief Jill Macyshon