The testing of a turbine that officials were trying to bring online to help power the city's hobbled drainage system led to an electrical fire at the Sewerage & Water Board South Claiborne Avenue power plant on Wednesday.

Officials said the fire didn't cause any major injuries or further diminish the city's current pumping capacity. But it did mark the latest setback for an agency that has been reeling since it became evident that an array of internal problems likely contributed to flooding last month in several neighborhoods.

The turbine is one of five used to power the S&WB's ancient pumps, about half of which rely on 25-cycle electricity, an archaic standard that is only directly available through the utility's in-house plant. But three of the four turbines that provide 25-cycle power have been down for months, leaving the S&WB to rely on generators and converting power from Entergy — which could be unreliable in a storm — to provide power to the pumps.

Turbine 4 is one of the two largest in the system, but has been offline since 2012 for a full refurbishment that was not supposed to be complete until December. Following flooding on Aug. 5, officials had hoped to rush its repair so it could be brought back into service in time to improve conditions this hurricane season.  

Workers were testing the almost completely refurbished turbine about 11 a.m. Wednesday when a spike in voltage caused a small fire in an electrical circuit breaker, said Paul Rainwater, a member of the S&WB's interim management team.

Employees at the plant were the first to fight the blaze using fire extinguishers, Rainwater said. New Orleans firefighters then arrived about 11:05 a.m. and soon brought the blaze under control.

Rainwater declined to discuss how much longer Turbine No. 4 may remain down following Wednesday's fire. He said the city has already asked a firm to begin working on any necessary repairs to the damaged electrical equipment.

However, Rainwater said officials were confident the turbine itself wasn't damaged.

One person fell during the emergency but refused treatment by paramedics, Rainwater said.

After the August flood, it was discovered that several S&WB pumps weren't working and staffing shortages had left some pump stations without operators during the storm. Questions were also raised about whether power rationing because of the offline turbines kept some pumps from being turned on until after the storm.

Mayor Mitch Landrieu's administration has been scrambling to fix the beleaguered agency, which has included replacing its leadership with an interim management team that includes Rainwater.

Wednesday's fire was the second at the power plant since the Aug. 5 flood. The first fire broke out in a control panel and knocked out one of the agency's two working turbines. That turbine has since been fixed. ​

Follow Ramon Antonio Vargas on Twitter, @RVargasAdvocate.

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