NEW ORLEANS — The New Orleans Sewerage and Water Board was operating several of its key pumping stations at about half power after an intense rainfall that likely would have produced some street flooding even under the best of conditions Saturday.
General Superintendent Ron Spooner said that the loss of the troubled and aged Turbine 4, while Turbine 5 had recently been taken down for repairs, left the Sewerage and Water Board with a problem.
“Once T4 went offline, there’s not enough power to distribute to all of the 25Hz pumps as needed so we managed that power to the best of our ability, and, with the breaking weather, it took longer than normal to get the water off of the street,” he said to a media gathering Monday afternoon.
Turbine 4, which was built in 1915 and Turbine 5 supply critical power to the current drainage system and without those two power sources, Spooner said the S&WB had to manage the power with frequency converters and EMDs.
EMDs are the Electro-Motive Diesel generators installed as backups in 2018 after turbine failure led to major citywide flooding in August 2017.
Spooner laid out essentially three scenarios for the city to handle drainage in the event of intense fall or hurricane events.
- Currently, T4 has been taken apart as they search for the problem that took it offline. Once they do that they can go about getting parts and estimating a timeline. While T4 and T5 are down, any heavy rainfall would need to be handled as it was Saturday, with power being managed at different pumping stations with only about half the pumping capacity of normal.
- T5 has been down since very late October and is expected back on in about 5 to 10 days. Once it is back on, they will be back to the situation they went into this weekend with, having a major turbine available plus the frequency converters and EMDs.
- When Turbine 4 and 5 are back online they would have those two power systems and the backup redundancy available. However, both turbines are old and have had issues.
- An energy substation is expected to be ready for peak hurricane season (usually August and September) in 2025. There will also be a backup power plant coming. Until that time though, one of the three above options will be the likely scenario.
Spooner did say that Saturday’s issues did not affect drainage and pumping in New Orleans East or Algiers, whose systems work with power supplied by Entergy.
“We do know this is an aging system,” he said. “We’re headed in the right direction and transitioning.”