The latest death happened Saturday when officials say 26-year-old Jennifer Lankford was swimming in the private lake located in Central Missouri.
Officials say Lankford and two boys she was swimming with felt an electrical current in the water. The woman swam to a nearby dock but was killed when she touched it. The boys safely made it to the shore.
Two children were killed by electricity just a few days earlier, on the 4th of July.
A 13-year-old girl and her 8-year-old brother were both electrocuted at a different dock on the lake.
According to Missouri State Police, investigators found multiple problems with electrical wires at the dock where the kids were swimming.
The electrocutions show just how important safety is when dealing with water and electricity, says Jared Trammel, Chief Ranger of Natural Resources on Beaver Lake with the US Army Corps of Engineers.
"It happens from time to time across the United States, but we haven't had any incidents on Beaver Lake," Trammel says. "We've been very fortunate."
He says seventy percent of the 1800 docks on Beaver Lake are electrified.
"Water and electricity don't mix so it's a safety concern you want to be aware of," Trammell says "Electricity in water is kind of a silent killer."
However, boat dock builders say electrified docks are perfectly safe, as long as they are wired properly. Karen Harris and her husband started building docks on Beaver Lake in 1986. She says the drownings on Lake of the Ozarks could have, and should have been prevented.
"Something was really done wrong," she says. "There was just no reason for them to get hurt no reason for them to get killed."
Harris says the Missouri lake is privately owned, and loosely regulated, unlike Beaver lake.
"The Corps of Engineers regulations are massive," she says. "But that's why we haven't had any deaths on this lake because of electrocution, because they do regulate it and they regulate it tightly."
Each private dock is inspected by a master electrician as part of the permit process, and every five years those permits must be renewed to make sure everything is still in working order.
"I have seen perch chew through electrical insulation on the lines," Harris says. "If that happens then that's feeding into the lake."
She says the key to providing power safely is a ground fault interrupter, or GFI, located on the shore. The breaker quickly cuts off power at the slightest surge.
"Lightning two miles away will flip a GFI breaker on a boat dock," Harris says. "A lot of people complain about that. 'I'm always turning that breaker back on...' but they're protecting people, beavers and fish from getting electrocuted.