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The City of New Orleans

Tropical Storm Cristobal Updates


Jun 05
4:31 PM
Tropical Storm Cristobal

Update on SWBNO preparations for Tropical Storm Cristobal

During preparations for the arrival of Tropical Storm Cristobal, the Sewerage and Water Board of New Orleans (SWBNO) Operations staff reported this afternoon, Friday, May 5, that an Electro-Motive Diesel (EMD) generator was in need of repair. The work is complicated enough that it cannot be completed before the arrival of the storm and therefore has been designated out of service.

While not a major loss of power, it is additional information that SWBNO learned since Executive Director Ghassan Korban spoke to the media Friday morning.

“We are capable of producing enough 25 Hz power to run New Orleans’ drainage system, but any loss of a power supply is a loss of redundancy and a concern for our operations,” Korban said.

Five EMDs were installed after the Aug. 5, 2017 flood event as backup power sources for the drainage system. Each are capable of producing 2.5 megawatts (MW) of the unusual 25 Hz electricity needed to run the city’s oldest pumps. With the loss of the 25 MW Turbine 5 in December, SWBNO moved the EMDs from backup to primary power sources.

The combination of the four operational EMDs, four operational turbine generators, four frequency changers, and Entergy power can produce more than 60 MW of power. The drainage system requires about 52 MW of power to run the greatest combination of its drainage pumps.

“We are very concerned that another major loss on the scale of T5 would force us to ration our power supply and choose which pumps around the city we could run at the same time,” Korban said. “We are in much better shape than we were in 2017, but the drainage system remains fragile until major investments in its future can be made.”

All 99 drainage pumps are operational and available. Three constant-duty pumps are out-of-service, but these are smaller units used to regulate groundwater in canals and are not large enough to be critical during a flood fight.

It is also important to emphasize that our drainage system is old and can be vulnerable to storm-related challenges. Tropical storms and hurricanes are inherently chaotic. Our staff is well-trained and prepared to respond as circumstances change and such challenges arise. The real issue is that we live below sea level, and while our drainage system can hold and move a considerable amount of water in real time, it has its limits. TS Cristobal is forecasted to be a heavy rain event with bands producing significant downpours. Residents should prepare for likely street flooding and pooling in low-lying areas. All underpasses should also be avoided because they are prone to flooding.