The incident happened Sunday morning, Aug. 4, in Oakdale.
An employee of the Oakdale Yacht Club, located at 520 Shore Drive, called 911 at 8:07 a.m. after observing a woman in the Connetquot River.
The woman, Catherine Andreau, age 62, of Babylon, was pulled from the water and pronounced dead at the scene, according to Suffolk County Police.
An investigation determined that Andreau, who was staying on a houseboat, jumped into the water at 1:30 a.m. to rescue her dog.
The dog was rescued and transported to a local veterinarian.
The body of Andreau was transported to the Office of the Suffolk County Medical Examiner to determine an official cause of death.
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