St. Bernard voters overwhelmingly voted down a proposal Saturday to increase a property tax that funds flood protection — a vote that could affect Orleans and Jefferson parishes, which are part of the same regional flood protection system.

The Lake Borgne Basin Levee District, which covers St. Bernard Parish, is responsible for maintaining the southern section of a system that shields the entire east bank.*

With a parish population half of what it was before Hurricane Katrina, the 11.1-mill tax isn’t meeting expenses, according to the levee district. The proposal would have raised the tax to 18.6 mills, a 67 percent increase.

Sixty-one percent of voters rejected that increase, along with other tax increases and renewals.

The vote won’t change flood protection overnight, said Nick Cali, executive director of the levee district, but it will force his agency to make hard decisions about where to cut costs.

“On Monday morning we’re going to sit down and talk about the next step in looking for money,” Cali said.

The Lake Borgne levee district takes in about $3.7 million a year. Right now it spends about $500,000 more than that, Cali said.

The agency has $5.2 million in reserve, he said, but its expenses will jump to roughly $6 million annually when the U.S. Army Corps of Engineers hands over the rest of the $14.5 billion flood protection system.

Bob Turner, regional director of the Southeast Louisiana Flood Protection Authority-East, said the anticipated shortfall can’t be made up simply by cutting expenses.

“There will be some things that we just won’t be able to do,” he said. “Until we find more revenue, the key will be to prioritize.”

The tax funds operation and maintenance of 60 miles of levees, 33 floodgates and two navigation floodgates. Unlike the other levee districts, the Lake Borgne district also runs the parish drainage system, which includes 55 miles of drainage canals and eight pump stations.

While only St. Bernard residents voted Saturday, the issue has implications for the rest of the east bank.

Because New Orleans, St. Bernard and East Jefferson sit on the same sinking delta, storm surge invading one parish can flow into the others.  That’s why the corps designed the new system as a perimeter defense — a chain of interlocking levees and floodwalls stretching from Kenner to Caernarvon.

The Southeast Louisiana Flood Protection Authority-East was established specifically to oversee operations of the three levee districts that maintain this system. But state law prohibits taxes raised in one district from being used in another.

The more populated parishes of Orleans and Jefferson have surpluses. But St. Bernard has struggled to meet the demands of the southern end of the system.

The east bank of Orleans Parish, with a tax rate of 11.67 mills, collects about $30.5 million a year. East Jefferson’s 3.91 mills brings in about $8.8 million.*

St. Bernard’s higher millage of 11.1 garners just $3.4 million because of its much smaller population and tax base.

Correction: This story originally misstated the name of the Lake Borgne Basin Levee District. It also misstated Orleans Parish’s flood protection tax rate and how much it brings in. (July 21, 2016)