NEW ORLEANS -- Eight of the city’s 121 pumps were not working during Saturday’s flood, a Sewerage & Water Board’s official told WWL-TV late Monday, but that had no effect on the agency’s efforts to drain the streets.

Earlier in the day, S&WB General Superintendent Joe Becker said seven were offline.

“There was simply just too much rain for the largest drainage system in the world to handle,” Becker told reporters at Pumping Station No. 1 in Central City. It was one of the stations that did operate a full capacity on Saturday.

Becker said that all 24 pumping stations were manned before, during and after the rainstorm that dumped as much as 9 inches of water in some of the lowest parts of the city.

“There were absolutely no delays in turning on the pumps at all,” Becker said. “All of the stations were staffed for all of this time.”

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Becker said an additional nine S&WB employees moved among various pumping stations throughout the day.

Neither he now the S&WB provides specifics about which pumps were out of service for Saturday's storm.

The pumps that were not working were down for "maintenance" and scattered at stations across the city, Becker said. But, he said, it is not uncommon for pumps to be offline.

"Because of the preventive maintenance work all the time, we do have pumps that are out of service at any given rain event," he said. "It's ... very unusual, very unusual for us to be able to use all 121 pumps."

About the same time Becker made his comments, Mayor Mitch Landrieu was across town preparing to begin a tour of Treme and Mid-City, which both saw heavy flooding. He announced he had ordered a report to determine if all the pumps were working properly.

“I'm just reminding everybody we're going through a $2 billion renovation of our entire sewerage and water drainage system. And we were able to get that money because we had issues. We're fixing the power plant and all of that stuff, but as far as I know, right now … all of the pumps were working,” he said. “If they weren't, we'll figure out which ones weren't and why but I don't think that's the case right now.”

Responding to concerns that water actually rose in some neighborhoods after the rain stopped, Becker said that was a side effect of water seeking its lowest point while the drainage system strained by too much rain at once struggled to catch up.

The city’s drainage system is designed to pump 1 inch in the first hour and ½ inch every hour thereafter. That translates to 3 inches in the first five hours. Some parts of the city received as much as 9 or 10 inches of water.

Becker said clogged catch basins also were to blame for any slow drainage. Last week, a City Council committee and the Department of Public Works heard from citizens across New Orleans who said they have seen no work to clear catch basins, despite claims that crews are in the streets to clean and repair them.

Stay with Eyewitness News on WWL-TV and for more on this developing story.