NEW ORLEANS -- The Sewerage & Water Board’s leaders didn’t spend much time at today’s board meeting dwelling on the boil-water advisory that was lifted.

Instead, a lot of time was spent discussing how to avoid such disruptions in the future. And what it could cost won’t be cheap.

Paul Rainwater, a member of the S&WB’s interim management team, explained that one of the massive turbines -- essentially a large generator -- that supplies power to the water-purification system went offline Wednesday morning.

The root cause of the outage, which spurred the sixth citywide boil-water advisory since 2010, remains unknown.

“The power outage was the result of a natural gas control valve malfunction. The cause of that is under investigation,” Rainwater told the board. “We’re investigating why steam pumps A and B did not keep water pressure above the 15 psi.”

That sparked a lengthy discussion about how the S&WB can ensure reliable power going forward: should the board buy electricity from Entergy or build its own new power plant?

The latter measure could be cost-prohibitive, Mayor Mitch Landrieu, who serves as president of the S&WB, told the board.

“If you have to build a new power plant, it's the equivalent, for the most part of building a new Superdome,” he said. “It's going to be one of the biggest expenditures that's been made.”

He added that Entergy would charge about $100 million to build a new substation to supply power to the S&WB plant.

Board member Alan Arnold argued that the problem of maintaining reliable power is nothing new.

“Three years ago I said power is a real problem,” he said. “There are solutions out there. Why didn't our staff bring those solutions to the board for a robust solutions then?”

The S&WB’s interim management team is expected to submit a list of short-, medium- and long-term solutions Oct. 15.

The bottom line remains that a more reliable sewer and water system will likely require additional property taxes or assessments, the board agreed.