Barbara L. Cantrell of Amesville and her husband William were in a minivan heading home just before midnight when they encountered high water, The Columbus Dispatch reported.
Lt. Darrell Cogar of the Athens County Sheriff's Office said the couple first waited to see if the water would go down then, after Barbara Cantrell felt water at her feet, tried to back up the van but it wouldn't start.
The couple climbed out of the vehicle and tried to make it to higher ground when Barbara Cantrell, who was using a walker because of recent hip surgery, slipped and fell, Cogar said.
She was swept away after her husband lost his grip on her.
William Cantrell, who was not hurt, called police from a home, and the Athens County dive team found his wife's body about 6:45 a.m. about a half-mile from the vehicle.
Athens County was one of many counties in Ohio under a flash flood watch into Saturday morning.
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