It was one of those summer afternoons that Georgia is known for, so hot that staying cool is the only task. To many, swimming pools and area lakes offer some relief from the blazing sun.

But on Sunday, waters 40 miles apart claimed two lives, providing another reminder of the need for water safety, investigators in two metro counties said. The circumstances in each presumed drowning were very different, but the results were deadly.

"You can drown in the shallow water of a bathtub," Chief Jason Shivers with the Forsyth County fire department said. It's an old adage, but still a reminder of the danger of water, Shivers said.

Shortly after 3 p.m. Sunday, a 7-year-old boy was found on the bottom an apartment complex swimming pool in southern Forsyth County. Deputies said the water was three to five feet deep.

Stephon Alston's father had stepped away from the pool to dry his face off in the restroom, according to investigators. When his father returned, he spotted Stephon's swimsuit in the pool, but the boy didn't resurface.

Stephon's father pulled him from the pool, and bystanders began CPR until deputies and firefighters arrived. But the life-saving efforts were too late.

Stephon was Forsyth County's first apparent drowning victim of the summer in a private swimming pool, Shivers said.

Less than two hours earlier, a 55-year-old Cobb County man disappeared while using a paddle board on Lake Acworth, according to police in the north Cobb city.

"He was with a friend, and the friend thought he was a good swimmer," Capt. Mark Cheatham with Acworth police told the AJC.

Thomas King, of Marietta, and a friend had rented equipment for their lake outing, but King was not wearing a life preserver when he went under, Cheatham said. Emergency responders were called around 1:40 p.m. Sunday to South Shore Park on Ragsdale Road. About 30 minutes later, Cobb County firefighters pulled King's body from the water.

A dam separates Lake Acworth from the larger Lake Allatoona, where two other people have drowned since late May, according to date obtained from the Georgia Department of Natural Resources. Last year, seven people drowned in Lake Allatoona, compared to 49 drownings reported in lakes statewide, according to the DNR.

Every incident, investigators say, is another reminder of the need for safety when planning to enjoy the water. Even the best swimmer should wear a life preserver, according to police and firefighters who are generally the first to respond to drowning reports.

"Complacency can be deadly," Cheatham said.

Ten people drowned in 2011 in Lake Lanier. This summer, the lake has had been the site of two deadly boating incidents that killed three children. Late last week, Rodrigo Bernal-Trejo, 44, of Cumming, died while on an outing with family at West Bank Park, another apparent drowning victim, Shivers said.

"He had family on the shoreline, but he was swimming alone," Shivers said.

Swimming alone is unsafe even for experienced swimmers, Shivers said, who can still be overcome by fatigue or cramps. If alcohol is involved, the potential for trouble grows, Shiver said. Many people are over-confidant in their swimming abilities, he said.

"It's not like riding a bicycle," Shivers said. "It's a skill set you need to maintain."

More information on swimming safety is available from the DNR website.