NEW ORLEANS -- Louisiana's governor declared a state of emergency in New Orleans on Thursday as the city's malfunctioning water-pumping system and the threat of more rain left some neighborhoods at greater risk of flooding.

The city scrambled to repair fire-damaged equipment at a power plant and shore up its drainage system, less than a week after a flash flood from torrential rain overwhelmed the city's pumping system and inundated many neighborhoods.

Gov. John Bel Edwards described his emergency declaration as a precautionary measure. He and Mayor Mitch Landrieu tried to calm the jangled nerves of residents still angry about the city's response to last weekend's flooding.

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"Obviously this is a serious situation, but it's not something to be panicked about," Edwards said at a City Hall news conference.

Floods that swamped New Orleans last weekend have cost several officials their jobs. As of Wednesday night, two officials in charge of the pumping and drainage systems were out, and Landrieu asked for more resignations, CBS News' DeMarco Morgan reported.

"When you have credibility issues around anything, whether it's a big or small contributor to a major event, you have to do that," Landrieu said.

Rain clouds gather over the New Orleans skyline in New Orleans, on Thu., Aug. 10, 2017. AP

Landrieu urged residents of some waterlogged neighborhoods to prepare for another possible round of flooding by moving vehicles to higher ground. All of the city's public schools were closed Thursday and were scheduled to be closed again on Friday.

Jamie Hill, a resident of the Mid-City neighborhood that has flooded twice in the past month, was clearing mud, sand, grass and other debris from the storm drain near her home. Her car flooded in an earlier downpour a few weeks ago. She said she's learned her lesson and now moves her car anytime it rains.

"I'm doing what I can, not that it will really matter if the pumps aren't working," she said.

New Orleans' municipal pumping system is supposed to move water out of the low-lying city. Having the system crippled in August could not come at a worse time for New Orleans, since the Gulf Coast is in the middle of hurricane season.

But officials feared that even a common thunderstorm would test the system's reduced capacity.

"With great prayer and a lot of hard work, hopefully we'll be OK," the mayor said.

Landrieu's office said in a news release early Thursday the city has lost service to one of its turbines, which powers most of the pumping stations that service the East Bank of New Orleans. Landrieu said that means the system's capacity to drain storm water from the streets has been diminished.

"It was an internal fire within the turbine itself, and it was a critical part," Landrieu said.

The mayor said the city is bringing in generators to back up the system and hoped to have them installed within 48 hours. Earlier, Landrieu said the power available early Thursday wouldn't be adequate to protect the city from another massive rainfall.

National Weather Service meteorologist Phil Grigsby said scattered thunderstorms and showers were in the daily forecast for the region through the weekend and into next week. But he called that a "fairly normal (weather) pattern" for south Louisiana in August.

"We can get a quick band of 1 to 2 inches of rain in an hour. Normally (the pumps) can handle that," Grigsby said. "But with the reduced capacity, it's something we have to keep an eye on."

Earlier this week, city officials and spokespeople had said repeatedly that all 24 pumping stations were working at full capacity. But after the system failed to keep up with a storm that dropped 9.4 inches of rain in three hours, the truth about the state of the water pumps began to emerge.

As heavy rains on Saturday created flooding scenes reminiscent of Hurricane Katrina, 20 of the city's 121 drainage pumps were out of commission, CBS News' Morgan reported.

One pump station operated at just 52 percent capacity.

"It is unacceptable that the public was not only uninformed, but misinformed as to our drainage system functionality during the flood," councilmember LaToya Cantrell said in a statement Wednesday.

Cedric Grant, one of Landrieu's top deputies and the head of the Sewerage & Water Board, told the city council Tuesday that he would retire at the end of hurricane season, which lasts through November.

Public Works Director Mark Jernigan submitted his resignation shortly after the council meeting, when he was asked whether his agency had done enough to clean the catch basins that feed the drainage system.

New Orleans is now looking for outside companies to take charge of the Sewerage and Water Board and look at the issues the agency had with pumps over the weekend, CBS affiliate WWL-TV reports.