Alyssa Hibben, 18, is one of 20 to 25 lifeguards on duty Monday at Pelican Harbor Aquatic Park in Bolingbrook. Each lifeguard at the park must complete a 20-hour initial training and certification process. (Chuck Berman, Chicago Tribune / June 15, 2014)

The drownings of four young children in the Chicago area over the weekend were tragic reminders that the lure of the water, while a tempting antidote to the hot months to come, can bring danger to almost any setting.

With summer upon us and temperatures this week heading into the 90s, more people will be heading to pools, ponds and beaches to cool off. But officials and experts warn that water fun comes with a risk, especially for children who don't know how to swim or are too young to learn.

The four weekend deaths, of children ages 3 to 9 took place at three very different locations — a backyard, a country club pool and a water-filled excavation site. Even though adults likely were nearby in at least two of the instances, children lost their lives.

"Most drownings, if not all of them, are preventable," said Veronica Resa, a spokeswoman for the Illinois Department of Children and Family Services. "A baby or toddler can drown in 1 inch of water in as little as 20 seconds, and they drown quietly. You won't hear them. It can be a baby pool, a bathtub ... any body of water."

Drowning was the leading cause of accidental deaths of children ages 1 to 4 in 2011, the latest year for which statistics were available, and the fifth-leading cause of unintentional injury death for all ages, according to the Centers for Disease Control and Prevention.

Three-year-old Liam Vaughn, of Rockford, was at a relative's home in Morris for a family gathering Sunday afternoon and had been playing in a large above-ground pool, according to Grundy County Coroner John Callahan.

Although the boy had been wearing "floaties" on each arm earlier in the day, he removed the flotation devices when he came out of the water to eat and did not put them back on when he re-entered the water unnoticed by adults, Callahan said.

"Even though you have other people in the pool, other children, you have several adults around the area and certainly respectable parents … it all happens within a matter of minutes," he said.

Callahan said flotation devices are a useful step in teaching children to swim, but the importance of wearing such devices is probably lost on young children who are sometimes overconfident in the water.

"A little 3-year-old probably thinks they can swim regardless," he said.

Dave Benjamin, executive director of the Great Lakes Surf Rescue Project, said one of the most important lessons his organization tries to convey during water safety training is that if a child is a nonswimmer, supervision should be in the water at arm's reach.

"If you're sitting on the beach, or you're sitting on a chair at the side of the pool … the misnomer is that children will yell for help, or splash or wave. But when they're actively drowning, they're not going to be able to do that," Benjamin said. "It may not even look like they're drowning."

The American Red Cross recommends that children start taking swimming lessons with a parent as early as 6 months of age, said Theresa Rees, territory aquatic specialist with the Red Cross of Greater Chicago, which works with city and suburban park districts and aquatic facilities to train lifeguards.

Beyond that, Rees said the Red Cross recommends that people of all ages swim only in public areas that are supervised by lifeguards.

Illinois requires lifeguards only at pools where children younger than 16 are allowed without a parent or guardian, and at all wave pools and water slides. The guards must be certified by the Red Cross, the National Pool and Water Park Lifeguard Training Program, the YMCA or other state-approved programs.

Under the state guidelines, where lifeguards are required, there must be a minimum of one lifeguard per 100 bathers or 2,000 square feet of water surface area.

It was not clear Monday whether the Royal Fox Country Club in St. Charles had lifeguards on duty when 4-year-old Paulino Delle Grazie drowned in a pool there Saturday afternoon.

St. Charles police Sgt. Mike Griesbaum referred questions about lifeguards to the club. Messages left for management were not returned Monday.

The St. Charles Police Department and DCFS are continuing to investigate the incident.

Resa said DCFS does not investigate all child drownings, but it will in the case of "an unusual death" or if there's reason to believe there was a lack of supervision.