The New Orleans City Council questioned Sewerage and Water Board Director Ghassan Korban at a Tuesday hearing to figure out what went wrong on May 12, when a boil water advisory was issued in a huge swath of uptown New Orleans. But after an hour of presentations and questions, the meeting ended without a clear consensus about what could have been done differently.
The boil water advisory was triggered by an Entergy New Orleans outage at a key Sewerage and Water Board pumping facility in the Carrollton neighborhood. The outage came after severe weather, including a tornado, although the outage occurred hours after the weather cleared out of the city.
Council members focused on how the Sewerage and Water Board and Entergy New Orleans could have communicated better. But Korban was skeptical it would have made a difference.
Council members also questioned whether the Sewerage and Water Board failed to adequately prepare for the possibility of an Entergy outage, given a confluence of factors: lower-than-normal water pressure due to construction, the temporary shutdown of a Sewerage and Water Board water tower and the fact that Entergy was working on the electric grid across the city in the wake of the bad weather.
The Carrollton Power Plant cleans and distributes tap water to the entire east bank of New Orleans. It sucks in water from the Mississippi River, purifies it and then pumps it out to homes and businesses.
When these pumps fail, water pressure falls. If water pressure falls too far, even for a short period of time, it is possible that the water can be contaminated. In these situations, the city will issue a boil water advisory until the water can be adequately tested to make sure no contamination occurred.
The Carrollton plant outage occurred at 6:13pm, well after the harsh weather had passed. The outage took two out of the four operating water pumps offline. Twenty minutes after the outage began, the water pressure dipped below 20 pounds per square inch, or psi, which is the threshold that triggers a water boil advisory. The water pressure climbed back up above 20 psi just 9 minutes later. The water boil advisory was lifted on May 14.
The Entergy power outage may not have been enough to trigger a boil water advisory on its own, Korban said on Tuesday. There were other factors that made the situation more urgent, including current repairs on a Sewerage and Water Board water tower.
The Sewerage and Water Board recently built two water towers at the Carrollton plant to avoid this very situation. The towers came online in 2018 and 2019. If the electric powered pumps go offline, the towers can maintain water pressure for approximately 40 minutes, acting as additional, short-term pumps.
But one of the two water towers was down for scheduled repairs on May 12.
“Because only one was online, we had half the time that we typically enjoy to allow us to react and adjust and stand up pumps,” Korban said.
Korban said the water tower repairs also caused the city’s water pressure to drop more than the agency anticipated, meaning there was even less time than usual to react to the power outage before the water pressure dipped below 20 psi.
Some council members questioned why the Sewerage and Water Board wasn’t doing more to prepare for a potential Entergy outage, given the lower than usual baseline water pressure and the fact that outages and repairs were occurring all around the Carrollton plant.
The Carrollton plant was not running two of its available water distribution pumps at the time of the outage. And a power generating turbine, which provides backup electricity in case of an Entergy failure, was off.
Ghassan defended those decisions, saying that while “hindsight is 20/20,” he didn’t make preparations for an Entergy outage because he had no reason to believe that they would be facing an Entergy outage. He said that when Entergy is doing repairs that could affect Sewerage and Water Board facilities, they are typically notified.
“This was a surprise to everybody,” Korban said. “And there was no anticipation for an outage, for a cutoff, otherwise they would have communicated with us. So it was one of those things where the circumstance just didn’t work to anybody’s advantage.”
The Carrollton Water Plant currently houses six active drinking water pumps. The plant usually has another two pumps, but Sewerage and Water Board communications director Courtney Barnes said that they are currently being refurbished with a federal Hazard Mitigation Grant.
‘We did not anticipate this happening’
Due to the system’s age, the six pumps use varying types of electricity. Two pumps run on 60-hertz electricity — the kind that comes from Entergy. One pump runs on 25 Hz electricity, which is an older and now nearly obsolete form of electricity. Another two pumps can run on either 25 Hz or 60 Hz electricity. And there is also one steam powered pump.
The 25 Hz pumps are powered by Sewerage and Water Board turbines that produce that specialized type of electricity. Turbine 6, which produces 60 Hz power, is supposed to act as a backup in case of an Entergy outage.
When the Entergy outage occurred, only four out of six of the pumps were running. Sewerage and Water Board communications director Courtney Barnes told The Lens that it is simple standard operating procedure to have only some of the pumps on. The Lens asked Barnes why the other two pumps weren’t turned on, given the lower than usual water pressure and higher than usual threat of an outage.
“One thing that’s important to remember is we did not anticipate this happening. This is not something we were prepared for to happen.”
Exactly 20 minutes after the May 12 outage, the water pressure dipped below 20 psi, triggering a water boil advisory. The Sewerage and Water Board attempted to switch on Turbine 6, according to Barnes, but it didn’t get turned on in time. It takes roughly 25 to 30 minutes to get the turbine online, interim general superintendent of the Sewerage and Water Board, Ron Spooner, said on Tuesday.
The water pressure rose above 20 psi again after 9 minutes, according to Korban’s presentation, after the Sewerage and Water Board brought one additional pump online and increased pump speed at another.
Several council members suggested that better communication between Entergy and the Sewerage and Water Board could have avoided the boil advisory. But Korban questioned how that would have helped.
Entergy New Orleans wasn’t aware that the outage was going to happen. The Sewerage and Water Board informed Entergy of the outage just four minutes after it occurred, and an Entergy official told the City Council on Tuesday that the company immediately sent a team out to fix it. It then took roughly two hours for Entergy to turn the power back on — much longer than the 20 minutes it took for the water pressure to dip below 20 psi.
Korban said that problems like this, which result from a confluence of different unfortunate factors, are still to be expected as the city tries to overhaul century old water and sewerage systems.
“I wish we could say this is the last time it will happen,” Korban said.
He said this instance demonstrated a need to continue investing in hardening and improving these systems.