As Minnesota’s celebrated boating season ramps up this month, one Edina family’s loss has propelled them to lead a small but sweeping change to the state’s big boating industry.

In the next year, thousands of boaters will have to install carbon monoxide detectors in their craft due to a new state law — the first of its kind in the nation — making them mandatory.

The legislation is called Sophia’s Law for 7-year-old Sophia Baechler, who died last October on Lake Minnetonka when carbon monoxide leaked from a hole in the boat’s exhaust pipe.

“I’m so heartbroken that we lost our daughter; I miss her so very much each and every day,” said her father, Ben Baechler. “I hope some good can come out of this tragedy.”

The bill passed in April after the family came up with the idea, lobbied for it and gave emotional testimony about the tragic day a few months before on the state’s most popular boating lake.

The law mandates that any motorboat with an “enclosed accommodation area” — which includes sleeping areas, galleys with sinks, and toilet compartments — must have a hard-wired, marine-certified carbon monoxide detector by next May 1.

Sophia Baechler, 7, died in 2015 from carbon monoxide poisoning on Lake Minnetonka.

“It’s a small investment to make when it can save your life,” said Sen. Melisa Franzen, DFL-Edina, one of the bill’s chief authors, adding that no one testified against the bill.

“We think this is a significant step to make sure boaters are safer,” she said. “Unfortunately it took a tragedy to bring that awareness.”

While some new boats already come with the detectors, owners of older boats will have to retrofit them. Portable or home carbon monoxide detectors won’t meet the rule.

Minnesota, which ranks No. 1 in the nation for most boats per capita, has more than 540,000 motorboats, according to the state Department of Natural Resources (DNR). The agency doesn’t track how many have enclosed accommodation spaces, but Stan Linnell, the DNR boating and water safety manager, estimates that about 8,000 boats will need carbon monoxide detectors under the new law. Those boaters also must post three warning stickers about carbon monoxide poisoning.

Other motorboats that have “an enclosed occupancy space” — smaller areas into which a person might enter — won’t be required to have detectors but will still have to have the stickers. The DNR estimates that will affect about 45,000 boats, and will mail the stickers and distribute them at licensing centers before they’re required May 1, 2017.

Boaters who don’t follow the rules will get a warning, then a citation. The law requires that all boating safety courses include the dangers of carbon monoxide poisoning, which DNR classes already do.

“If you’re not paying attention to it, it can kill you,” Linnell said of carbon monoxide.

Boat manufacturers seem to support the new mandate. The American Boat and Yacht Council, which develops widely used safety standards, is requiring carbon monoxide detectors on new boats with enclosed accommodation spaces starting in August.

“It could be a good step forward for safety,” said David Dickerson of the National Marine Manufacturers Association.

A hidden danger

Death by carbon monoxide poisoning on boats is fairly rare, but it’s a hidden danger given that the toxic gas is odorless and invisible. According to the DNR, there have been three such deaths in Minnesota over nine years. In 2013, two men fishing on Lake of the Woods died from carbon monoxide caused by a faulty exhaust system.

Then last year, Sophia died.

“It’s just a senseless loss of life,” Ben Baechler said. “These deaths are 100 percent preventable.”

Carbon monoxide poisoning can happen when the gas builds up from an idling motor, generator or faulty motor exhaust system. Symptoms include headaches, dizziness, weakness, nausea, vomiting, chest pain and confusion.

In 2006, a woman was found unconscious on Minnetonka’s Cruiser’s Cove, where boats tie up. In 2013, a girl got sick after tubing about 20 feet behind her family’s boat. Both lived.

That’s why the Baechlers and some legislators pushed for detectors in all boats, not just enclosed ones.

Know the law • Owners of motorboats with an “enclosed accommodation compartment,” which includes sleeping areas, galleys with sinks and toilet compartments, must install a hard-wired marine-certified carbon monoxide detector, and also post carbon monoxide warning labels at the stern, steering station and enclosed area, by next May 1. • Owners of motorboats with an “enclosed occupancy compartment” — any structural space intended for a person to enter — must post carbon monoxide warning labels at the stern, steering station and enclosed area by next May 1. • All state-approved boating safety courses must include details about carbon monoxide poisoning.

“All boaters are vulnerable to carbon monoxide,” Ben Baechler said. “Once you realize something is wrong, it may be too late. The key is, we need to detect it early.”

Deadly day on the lake

The DNR advises boaters not to leave motors idling or generators running while anchored or docked, not to sit on the rear swim deck while the motor is running, and to stay back at least 20 feet when water skiing or tubing. Motors and exhaust systems should be maintained each year, especially in the fall when animals can chew through pipes.

That’s what happened with the Baechlers, as they enjoyed a rare 80-degree October day on crowded Lake Minnetonka.

A muskrat had chewed through the exhaust pipe, creating a hole underneath a mattress area in the 1984 Carver 28-foot cruiser. The gas had leaked into the boat, affecting everyone on it. Sophia went below deck to rest after complaining about a headache. Seven minutes later, her father found her lifeless.

Her parents, both doctors, gave her CPR and met responders at Wayzata Bay. But Sophia was pronounced dead at the hospital of accidental carbon monoxide poisoning. The family had been on the boat for 35 minutes.

Still grieving their loss, the Baechler family is spreading awareness to prevent a similar tragedy. The new law is a “great start,” Ben Baechler said, and they hope it will be considered nationally.

“We’re confident this law will save lives,” he said, “and it will help remember Sophia. … In the Land of 10,000 Lakes, Minnesota is and should continue to lead the way in boating safety because it’s such a way of life.”

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