MINNEAPOLIS (WCCO) — The Hennepin County Sheriff’s Office is investigating the death of a second-grader who died of carbon monoxide poisoning while boating.

Sophia Baechler was unresponsive when paramedics responded to the 911 call at a dock in downtown Wayzata on Sunday afternoon.

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She was rushed to Hennepin County Medical Center, where she later died.

The DNR says carbon monoxide deaths while boating in the state are rare. From 2005 to 2014, there were only three injuries and two deaths.

But for one local father, this recent tragedy is a reminder of how close he came to almost losing his daughter.

“My heart aches,” David Schuester said. “It really brought back some horrible memories.”

It was July 4, 2013, and the Schuesters were in a Maple Grove boat parade. Four-year-old Sierra was on the boats swim deck.

“She started crying and was out of it,” Schuester said. “My wife, who is a nurse, said she has got carbon monoxide poisoning.”

Sierra was rushed by ambulance to Hennepin County Medical Center, where they have a hyperbaric chamber. She was there for six hours.

“She had lethal levels of carbon monoxide in her blood,” Schuester said. “We spent Fourth of July at HCMC, scared to death.”

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Sierra recovered fully, and the Schuester’s retrofitted their boat so the engine fumes are directed into the water. Now, they always have a portable carbon monoxide detector on board.

“Boating can be dangerous,” Schuester said.

Steve Leighton, a long time member of the boating safety group Minnetonka Power Squadron, agrees. He has two carbon monoxide detectors on his boat and a warning to keep the cabin door closed.

“If you’re going downwind at 5 mph and you have a 10 mph tailwind, your fumes are coming right into your cabin,” Leighton said. “I have had my carbon monoxide detector go off when I am just cruising around the lake.”

Minnesota does not require carbon monoxide detectors on boats.

Police are still not releasing the details of exactly what led up to Baechler’s death.

And while the DNR cites three injuries and two deaths in nine years, the figures could be higher. The DNR on Tuesday acknowledged their numbers account for only cases reported directly to them.

The symptoms of carbon monoxide poisoning include headache, dizziness, weakness, vomiting, chest pain, and confusion.

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If you suspect carbon monoxide poisoning, call 911 immediately.

Esme Murphy