Perhaps the most perilous threats around sandbars at inlets and beachfronts across the Lowcountry are not even visible — rip currents, quick-changing tide patterns, perpetually shifting the landscape.

And yet, weekend after weekend, holiday after holiday, these sandbars remain among the most popular places to anchor boats.

The allure?

"I think people see them as great places to go out in the water and be perfectly safe, and that's not the case," said Tom Gill, a spokesman for the U.S. Lifesaving Association.

Swimmers will get out of  their boats and wade through knee-high water while the sandbar, slowly but surely, disappears beneath the surface as the tide rises.

"The whole dynamic atmosphere of the area can be extremely dangerous when people are not prepared for what's coming next," he said.

Shifting tides

Nearly every summer, news reports of beach-goers here and elsewhere who get stranded or are swept out to sea after swimming in these well-visited areas tend to spur dialogue around sandbar safety.

Most recently here, the body of 11-year-old Khandi Whitley, who was visiting from North Carolina, was recovered late last month near the Limehouse Bridge on the Stono River after authorities said she was pulled from a sandbar by a strong current.

Others who had been aboard the boat Khandi was on tried to toss life preservers to the girl before she went under. After about a 16-hour search, which comprised nine marine units, her body was found in the middle of the river north of the bridge, authorities said.

That same day, July 23, authorities were summoned to a similar situation on Sullivan's Island.

A 10-year-old on a paddle board near Station 29 had been pulled from a sandbar and into the ocean as the tide was going out. The girl's father was able to reach her in time, and the two washed up on a sandbar beyond the breakers, where they were rescued by authorities on jet skis.

"(Swimmers and boaters) definitely need to be aware of their surroundings, especially if you swim out to a sandbar," said Nikki Bowie, safety program manager for Charleston County Park and Recreation Commission. "If they do get caught, the big thing is they think (rip currents) pull you under, and they don't ... relax and let the current pull you, because it will dissipate."

Each year, more than 100 people across the United States die from rip currents, according to a recent report from The New York Times.

Notably, in the summer of 2009, local authorities responded to a rash of water rescues across Lowcountry beaches.

The body of one Goose Creek woman, Tara McAllister, 39, washed up on the shore of Folly Beach in early July of that year. She had gone for a swim and never returned. The Charleston County Coroner's Office later ruled she drowned.

Days later, a woman in her 20s named Anna Finkelstein, who was visiting from New York City, disappeared after venturing out to a sandbar on Sullivan's Island and becoming trapped in a rip current. A friend with whom she was swimming managed to escape and swam for help before Finkelstein was pulled out to sea.

The same week, at least three other swimmers had to be rescued, also at Sullivan's.

Cases like these highlight the importance of educating those venturing into the water on how to best protect themselves against threats such as rip currents that can snake along sandbars, officials said.

Rip currents aside, Gill also said other "inherent risks" present around sandbars include shifting tide patterns and, naturally, the ever-changing nature of the sandbars themselves.

The underlying concern?

"It's made of sand," said Gill. "It's not something that's going to exist forever. It can break down over a month, over a week, over a day. It's not a constant."

Tracking emergency response

It's hard to know just how often emergency officials respond to incidents on sandbars across the Lowcountry, although authorities say it's relatively common.

Lt. Eric Lunde, who is Coast Guard Sector Charleston Command Center chief, said in an email that the Coast Guard does not maintain publicly available statistics regarding sandbar rescues. However, he added, “the USCG receives reports of missing swimmers frequently.”

State and local authorities typically take the lead in these cases, according to the Coast Guard, which can include the assistance of non-law enforcement groups such as lifeguards from the Charleston County Park and Recreation Commission. Lifeguards with CCPRC are certified emergency medical responders, according to the commission.

The lifeguards — employed seasonally and stationed at Folly Beach County Park, the area around the Edwin S. Taylor Folly Beach Fishing Pier, Kiawah's Beachwalker Park and the Isle of Palms County Park — are responsible for roughly 1½ miles of beach on three barrier islands, according to the PRC website.

To put that number in perspective, there are roughly 35 miles of beach across Charleston County, according to Bowie.

"If you’re not in the areas where lifeguards are, definitely check the area out first," Bowie said. "(Sandbars) are an area where families like to go (because) it looks so calm, and it's low tide, you can walk out and it's easy."

She cautioned:

"But the tides come in, and those people get in trouble."

Reach Michael Majchrowicz at 843-607-1052. Follow him on Twitter @mjmajchrowicz.

Michael Majchrowicz is a reporter covering crime and public safety. He previously wrote about courts for the Daily Hampshire Gazette in Northampton, Massachusetts. A Hoosier native, he graduated from Indiana University with a degree in journalism.