Workers dumped rock and sandbags into breaches in the city's Industrial Canal throughout the night and were expected to complete the repair Sunday, said Mitch Frazier, a spokesman for the corps.
The storm surge created by Rita eroded repairs made after Hurricane Katrina and sent water surging back into the already devastated Ninth Ward. Once the breach is closed, engineers now believe the area could be dry in a week, Frazier said.
Federal officials had said Saturday it would take two to three weeks to pump out the water delivered by Rita.
But CBS News correspondent Sharyn Alfonsi
Despite that the still flooded Ninth Ward is void of residents, the sun was shining there Sunday morning, Alfonsi reports.
"It looks like the weather is improving," said Frazier. "That's good news."
The Corps of Engineers trucked rocks and airlifted giant sandbags to plug one of the ruptured levees, but the corps' commander on the ground was leery about how stable the makeshift repairs to the city's fragile flood-control system would prove.
"It's so dependent on the weather," said Col. Richard Wagenaar, the corps' district chief in New Orleans.
On Saturday, Mayor Ray Nagin renewed his delayed plans to allow some residents to return to the drier parts of the city. He said he thought the dry districts would eventually support a population of between 250,000 and 300,000.
Nagin said he wanted residents of the Algiers neighborhood, which has electricity and water, to start returning as early as Monday or Tuesday, followed by people in other ZIP codes.
"We're talking about people who are mobile. We're not asking people to come back who have a lot of kids, a lot of senior citizens," he said. "That's going to be the reality of New Orleans moving forward."
Even after the latest hurricane crisis eases, and downtown businesses along with French Quarter topless bars reopen, life in New Orleans will be far from normal. Among the somber distinctions: For months to come this will be an almost childless city.
Dozens of schools were irreparably damaged by Hurricane Katrina, and only a handful are expected to open before January. Few day-care centers will be available for preschoolers, and health experts warn that children are at extra risk of contamination if they come back before the city is thoroughly cleaned of the foul floodwater's residue.