Despite doubts expressed by many residents, New Orleans officials again insisted in a news conference Sunday morning that the city's drainage pumps worked as designed in the sudden floods that inundated much of the city Saturday afternoon.

Such flash flooding is a fact of life in the bowl-shaped city, Deputy Mayor Ryan Berni said, and one that could become more prevalent with climate change. He said Saturday's storm, depending on where you live, could be classified as a 10-year storm or a 100-year storm, and it was the second major storm in 15 days.

"Anytime you have multiple inches of rain in a short period of time, you're going to have street flooding in some areas," he said. "Part of living here is living with that threat."

Berni also warned that heavy rains expected over the next few days, in particular Monday afternoon, could pose the threat of more flooding, especially because the ground is already so saturated with water that it can't absorb much more.

Berni said he understood that residents were "frustrated" with the flooding, but emphasized that "all 24 Sewerage & Water Board pumping stations were operational and active throughout the event yesterday."

Nonetheless, he said the administration will conduct an "after-action report" -- a full written review -- "for folks who are wondering, just to make sure that everything was done as perfectly as possible in these events."

In response to a reporter's question about how long it took to clear some areas of standing water, Berni said: "We have no information that suggests that the pumps weren't working as designed." But he added: "We're going back over to make sure there weren't any minor issues."

He noted that water often continues to pool in lower-lying areas as it sluices away from higher elevations, which can lead those watching water levels to believe pumps aren't doing their job.

"Where I live, the water rose (after the rain stopped) before it went down," Berni said. 

In Saturday's rains, some of the lowest-lying areas also happened to get the most rain. Mid-City, for instance, often referred to as the bottom of the bowl in the city's topography, got more than 7 inches of rain in just three hours.

Berni also said some residents were under the mistaken impression that the pumps at the lakefront on the Orleans, London Avenue and 17th Street outfall canals should have been in use Saturday. That equipment is designed to be used only in hurricanes, he said, when storm surge can push water into the canals as it did to devastating effect in Hurricane Katrina.

In that scenario, gates at the mouths of the canals are closed and the water is pumped out. "They are not intended to be used in rainfall events like the one we had," Berni said.

At this juncture, the Landrieu administration has no plans to seek a federal emergency declaration, Berni said but that could change depending on how much damage is catalogued. He said fire and police officials have been conducting a "windshield survey" on Sunday, assessing damage by driving around town and observing it.

Sanitation crews will pick up debris, such as sodden carpet and drywall, if residents leave it on the curb, Berni said. 

Mayor Mitch Landrieu was not at the news conference, which took place in front of City Hall Sunday morning. Berni was accompanied by Cedric Grant, executive director of the Sewerage & Water Board, and Aaron Miller, the city's homeland security director. 

Later Sunday, Berni told The Advocate that Landrieu left town Friday for Aspen, Colorado, to attend a conference on public safety and security. The mayor will be back in New Orleans on Monday morning, Berni said, adding that Landrieu has been "in constant communication" with his top aides.

City officials also said Sunday that dozens if not hundreds of stranded vehicles continue to make some intersections in New Orleans impassable, warning that some vehicles may be “courtesy towed” if residents are unable to move them.

Owners of vehicles stuck in the middle of roadways or intersections are asked to move them to the side of the road or a parking lane “immediately,” officials said in a news release.

In order to reopen traffic, the Department of Public Works and New Orleans police may “courtesy tow” vehicles to the side of the road. Any vehicles abandoned on interstates or major roadway ramps may be towed to the city’s impound lot. Residents will not be charged to retrieve their vehicles, according to the news release.

With more rain expected today, residents will be allowed to park on neutral grounds to keep intersections and streetcar tracks clear, the news release said.

All vehicles must be removed by midnight Sunday so that RTA and other services can operate on Monday morning, officials said.

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