Saul Young / AP

The scene at German Creek Marina in Bean Station, Tenn., on Wednesday after several children were shocked while swimming.

When Kevin Ritz read about the children who died after being shocked by electricity while swimming in lakes in Missouri and Tennessee on Wednesday, he thought about his 8-year-old son, Lucas, and the dozens of others who have died this way.

“Everyone goes, ‘How can that happen?’” Ritz said.

In 1999, Ritz’s children were swimming in the Multnomah Channel of the Willamette River in Oregon when suddenly, Lucas let out a gasp and apparently became unconscious. His life jacket flipped him over so that his face was out of the water. As his wife jumped in the water to save their son, she felt paralyzed, a feeling she attributed to fear. His other son later reported that he, too, felt numb and tingly.

Law enforcement officers told Ritz that his son had drowned, but Ritz pushed them to investigate further. His son’s face, he said, hadn’t been submerged and he had been wearing a life jacket.

“With my digital voltmeter, I went to the area where Lucas had been, put the negative lead to a ground, dropped the positive lead into the water, and immediately got AC voltage,” he wrote in an essay about his son’s death. “I notified the Sheriff’s Department, reporting what I had found and that I wanted to get someone to confirm my test. They agreed to send out some deputies while I called in an electrician. He arrived later that morning, tracing the electricity to a powerboat that was in the area where the kids had been swimming.”

Children electrocuted while swimming in lakes

In the throes of grief, Ritz, now a marine electrician, started agitating for safer marinas. It infuriated him, for example, that electrical outlets at marinas were not held to the same standards as outlets in bathrooms.

“The European market has had ground fault protection in their marinas – the power coming into the marina at the docks – for over 25 years,” Ritz told msnbc.com. “How come we can’t have that?”

The obstacles are many, however. Ritz said that a marina manager near where he lives wanted to upgrade some of the marina’s electrical system but learned that, by law, he would also have to upgrade the whole system – a pricey proposition.

Herb Hall, president of Sierra Boat Co., a Lake Tahoe marina specializing in classic and wooden motorboats, said having good electrical systems on the docks is discussed at an annual marina conference, but that some marinas “unfortunately aren’t successful and don’t have the money to maintain things.”

“On an annual basis, you need to be inspecting out on your docks,” Hall said. “Most marinas have floating docks. You have flexible connections going out on the docks that are moving all the time, and those chafe and wear and separate.”

2nd boy dies after shock incident in Tenn. lake

Ritz works with David Rifkin to keep a list of those who have died from what they call electric shock drowning. Their list is anecdotal, because that cause of death is impossible to determine in an autopsy, Ritz said.

Rifkin counts more than 50 people who have died in that manner since the mid-1980s, but he said the actual number is likely many times that.

“Most of the time when these things happen and there’s no reason to believe it’s electrical in nature, it’s listed as a drowning,” Rifkin said. “We’re thinking the numbers could be one hundred-fold.”

Rifkin’s list does not include those that occurred Wednesday – he said he does not yet have enough information to include them.

But the deaths on the Fourth resemble the others on the list, in that all occurred in freshwater. Alexandra Anderson, 13, and her 10-year-old brother, Brayden, were swimming in Lake of the Ozarks, a freshwater lake in Missouri. Noah Winstead, 10, and his friend Nathan Lynam, 11, died after being shocked in Cherokee Lake in Tennessee.

Rifkin has no documented cases of deaths in saltwater. He says that’s because of the high voltage gradient that would have to be present.

“When these things happen, I'm often called in to find the electrical fault,” Ritz said. “I spend a good portion of my life educating first responders and law enforcement on this issue in hopes that lives will be saved.”

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