NEW ORLEANS -- Frustration is boiling over as a new power problem forced the Sewerage and Water Board to issue another boil-water advisory Wednesday morning.

It was at least the eighth time since 2006 that a loss of power caused water pressure to drop below the safe level of 15 pounds per square inch. The Sewerage and Water Board used to brag that it only had to issue one such boil-water advisory in the 100 years before Hurricane Katrina caused major damage to their water, sewer, drainage and power systems.

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The S&WB’s self-generation of power has been a major issue since rainstorms caused significant flooding July 22 and Aug. 5 and Mayor Mitch Landrieu’s administration acknowledged that lack of power played an important part in the drainage failure. Turbines No. 3, 4 and 5 were all down for repairs during those floods and Turbine No. 1, the smallest of the S&WB’s four steam-run generators, overheated a few days later.

The one constant source of electricity that had not been lost through that drainage crisis was Turbine No. 6, a new turbine and generator supplied by the U.S. Army Corps of Engineers. It supplies backup power for drainage pump stations, but it’s the primary source of power for the S&WB’s potable water and sewer systems.

But Turbine 6 suddenly went offline Wednesday morning, causing the loss in pressure, according to the leader of Landrieu’s interim S&WB management team, Paul Rainwater.

“Obviously, Turbine 6 is a new generator,” Rainwater said. “We’re having an investigation done right now to find out what exactly happened.”

Rainwater said it took 20 minutes for backup power from Entergy to kick in and restore the water pressure, but Entergy spokeswoman Charlotte Cavell said the power utility had no problems on their end.

It’s unclear why it would take so long for the S&WB to tap into those Entergy power sources, but Rainwater said they are still working on establishing an automatic switch-over to Entergy when the self-produced power fails.

“One of the things we’re trying to address is to make sure that our redundancy systems kick on a lot quicker, or are they automatic,” he said. “Those are things that aren’t here yet and those are the things the mayor has been addressing since he’s been in office.”

Landrieu has been in office for seven and a half years and is the president of the Sewerage and Water Board.

Rainwater would not provide specific information about why they lost power from Turbine No. 6, an $18 million gas-fired combustion turbine and generator that was purchased and installed by the U.S. Army Corps of Engineers in 2012.

On Wednesday around 7 p.m., Mayor Mitch Landrieu's office reported that Turbine No. 6 was brought back online and was running off of diesel fuel. The mayor's office added that the cause of the turbine outage is still under investigation.

The Corps used $31 million that was authorized by Congress after Hurricane Katrina to get the turbine, build a new power plant building for it, install transformers and connect it to the Sewerage and Water Board’s grid.

The Corps officially turned the equipment over to the S&WB to operate and maintain in March 2016.

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Meanwhile, the S&WB is banking on a new method of keeping potable water sanitary. It is using federal Hazard Mitigation grant money to build and install two 200-foot-tall water towers at the Carrollton facility, which will allow them to supply uninterrupted water pressure for 40 minutes if power is lost. The first of those will not become available, however, until late 2018, Rainwater said.