NEW ORLEANS – Taps in New Orleans briefly went dry Sunday after a boiler’s heating flame went out of control in the immense steam generator that powers pumps for the city’s water treatment plant.

Marcia St. Martin, executive director of the city’s Sewerage and Water Board, said the outage lasted less than 20 minutes Sunday morning. Twitter came alive with residents bemoaning the loss, and Mayor Mitch Landrieu tweeted to his followers that the city was looking into the matter.

The loss of pressure opened the way for possible contamination and water samples are being taken citywide, she said.

She said all sample collection should be complete by Sunday afternoon, and results should be available about 24 hours later. It takes that long to detect high levels of intestinal bacteria that could cause diarrhea.

Until the results are in, officials said, more than 300,000 residents on the Mississippi River’s east bank should boil water for drinking, brushing teeth and preparing food.