Sewerage and Water board says Entergy problem, then internal issues led to pressure drop

Series of failures led to boil water advisory

Dave Cohen, WWL First News early edition
November 19, 2018 - 10:32 am
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The head of the New Orleans Sewerage and Water Board is calling on Entergy to harden its system after a power loss that started a series of events that resulted in a water pressure drop and boil water advisory in New Orleans.

Executive Director Ghassan Korban said an Entergy pole "was compromised" and the power went out to one pumping site.

When the S&WB attempted to power other pumps after the Entergy power loss, a breaker tripped shutting down additional pumps.

He explained that the new water tower designed to prevent pressure losses in these circumstances did its job, but crews took too long to resolve the problem.

Korban explained that it took S&WB about 30 minutes to get pumping restored, and the water tower can only provide 20 minutes of relief.

The boil water advisory for all of the Eastbank of New Orleans was issued Saturday and lifted Sunday.

Korban said he was meeting with Entergy today to discuss the issues.

He explained that they have been discussing Entergy building a new power substation to better provide electricity to S&WB.

(Click play below and turn up the volume on the video to watch and listen to the news conference.)

Officials released the following information on the series of events that led to the boil water advisory:

Mayor Cantrell, SWBNO Chronicles Events Leading to NOLA East Bank Boil Water Advisory Issued on Nov.17

The Sewerage and Water Board (SWBNO) has investigated the series of events that led to the boil water advisory on Saturday, Nov. 17 resulting in the issuance of the precautionary boil water advisory.

This narrative is part of an ongoing effort by SWBNO to increase transparency and accurate accounting of its operations to its customers and the public.

The Carrollton Water Plant on Claiborne Avenue has eight pumps that distribute potable water to the East Bank of the City of New Orleans. There are no booster pumps or intermediate pumps in the system, so water must rely on the power of the pumps to travel from Carrollton to the furthest point in our service area, such as Venetian Isles, and everywhere in between. SWBNO runs four water pumps at all times with four reserve pumps on standby in case an issue arises.

At 4:17 a.m., Carrollton Water Plant pump B (steam pump), Panola Station pump #2 (60 Hz), Claiborne Station pump #4 (25 Hz) and Claiborne Station pump #2 (60 Hz) were operating normally. Additionally, Claiborne Station pump #3 was operating on standby.

At 4:18 a.m., an Entergy pole was compromised near the Carrolton Water Plant in the 8700 block of S. Claiborne Avenue which caused a loss of power to Panola Station pump #2 due to an Entergy Feeder being out of service. Following this loss of power, the Carrollton Water Tower began stabilizing the system.

At 4:24 a.m., Claiborne Station pump #3 (60 Hz) was brought on line. Shortly thereafter, SWB officials contacted Entergy to understand the status of the situation and length of time for power to be restored.

At 6:19 a.m., the 60 cycle main breaker at the Claiborne Station tripped causing SWB to lose two pumps.Following this loss of power, the Carrollton Water Tower stabilized the system for about 20 minutes.

At approximately 6:42 a.m., the water tower was depleted before an additional pump was brought on line causing a drop in system pressure at various locations across the East Bank of New Orleans. The lowest system pressure reported was 7 psi. Prior to depletion, SWBNO officials attempted to bring Claiborne Station pump #1. However, due to operator error, the pump was unable to come on line.

Approximately 2-3 minutes after the system pressure dropped below 20 psi, Claiborne Station pump #1 was brought on line and the main breaker was corrected bringing Claiborne pumps #2 & #3 on line.

At approximately 6:50 a.m., this system restored pressure above 20 psi.

Last week, the SWBNO brought into service one of two large water towers. It was able to stabilize water pressure in the distribution system, giving SWBNO staff approximately 20 extra minutes to make adjustments.

The second water tower is scheduled to be completed in spring 2019.

Consistent with LDH’s requirement and out of an abundance of caution, SWBNO staff contacted LDH on Saturday, Nov. 17, 2018, and issued a precautionary boil water advisory for the East Bank of New Orleans.

SWBNO chemists began testing water quality samples around 4 p.m. on Saturday, November 17, 2018. The samples were incubated to determine whether there was a presence of harmful bacteria in the water.

After water quality samples found the drinking water to be safe, and after again conferring with LDH, SWBNO lifted the boil water advisories for all areas of the City shortly before noon on Sunday, Nov. 18.

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