Oleg Shneper, manager of the Extended Stay America hotel in the Cincinnati suburb of Blue Ash, said occupancy was down about 10 percent already.
His hotel usually gets business travelers and a lot of people visiting nearby Kings Island amusement park in Mason.
"People have called to say they can't get here because the rain is keeping them from getting out of airports," he said. "We're also definitely not seeing as much family traffic."
Farther south, the storm victims included a man and a woman discovered late Thursday in a home in the hard-hit town of Braithwaite, south of New Orleans; a man killed in a restaurant fire; two men killed in separate car accidents, a woman whose car was hit by a tree and a man who fell from a tree.
In Louisiana alone, the storm cut power to 901,000 homes and businesses, or about 47 percent of the state, but that had decreased to 617,000.
More than 15,000 utility workers began restoring power to customers in Louisiana and Mississippi, but officials said it would be a couple of days before power was fully restored.
Crews intentionally breached a levee that was strained by Isaac's floodwaters in southeast Louisiana's Plaquemines Parish, which is outside the federal levee system. Parish President Billy Nungesser said the work was slow-going. Workers were only able to reach one spot, he said, and 10 to 12 cuts were planned. The levee is cut as the tide goes out, he said, then patched while the tide comes back.
In Mississippi's Bay St. Louis, Allen Barrilleaux, spent Friday morning draining water from the engine of his flooded truck not far from a river.
He had planned to ride out the storm with his wife, a friend, and 5-week-old son in their house, which is on stilts, but called for help Wednesday when the water came closer and large pine trees from a nearby mill swirled in the water. They were evacuated by boat.
Watching for ant beds as he walked around his green Chevy, Barrilleaux said hurricanes are part of life here, but disasters can hit anywhere.
"Life's cruel," Barrilleaux said, gripping a wrench with a greasy hand. Then he smiled.
"We're like that big old ant hill and a guy with a lawnmower just keeps mowing us down."
Plaisance reported from Lafitte. Contributing to this report were Associated Press writers Kasie Hunt in Lafitte; Brian Schwaner and Janet McConnaughey in New Orleans; Melinda Deslatte in Baton Rouge; Kevin McGill in Houma; and Holbrook Mohr in Bay St. Louis, Miss.
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