Landrieu spoke to residents of the parish west of New Orleans at a community meeting Wednesday evening, The (New Orleans) Times-Picayune reported.
"When the rest of the country doesn't get funded, it's an inconvenience. It's a problem, etcetera, etcetera. When we don't get funded, we drown," she said.
St. John the Baptist, which is divided by the Mississippi River, was hit hard by Hurricane Isaac in August. Landrieu said it is time for the government to act.
"Our levees in this parish were authorized 40 years ago," she said. "They've been studied and studied. It's never been done."
Iranian woman stops the execution of son's killer
Disney's 'Jessie' to feature network's first engagement