STOCKTON, Calif. — A father and daughter were found dead on their houseboat on July 5, according to the San Joaquin County Sheriff's Office.

The pair was identified as 57-year-old John Lebarre and 26-year-old daughter Denielle Lebarre both of Discovery Bay.

The sheriff's office said the fiance of John Lebarre made a 911 call shortly after 4 a.m. after discovering John and Denielle on their boat, anchored near Ski Beach west of Holt in the Delta.

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According to the sheriff's office, most newer models of houseboats have CO sensors and alarms to warn of CO buildup and pooling. However, older model boats like the 1971 Nautaline houseboat where the pair was discovered are not required by California law to be equipped with carbon monoxide detectors.

"The exposure is great out here with the ski boats and the teak surfing that's going on where somebody is pulling on the back of the swim deck floating behind the boat while the motor is on. And, they are getting exposed to carbon monoxide," said Deputy Brian Merritt from the sheriff's office's Boating Division stationed at Stockton's Buckley Cove.

Merritt said state law does require decals placed on boats that warn of the dangers of CO poisoning. 

Although rare, this is not the first CO deaths on a boat in San Joaquin County. Merritt said about eight or nine years ago, two other people died of CO poisoning on a boat.

He says the symptoms of CO poisoning can be deceptive.

"You may feel dizzy, light headed, but a lot of people associate that with other situations out here, the environmental side of it with the heat. They may not know its a carbon monoxide issue," said Merritt.

The exact cause of death is still pending.

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