A 9-foot rip developed on a Napa water main Wednesday night, causing water to gush into the street and cutting off water for about 16 hours to more than a dozen customers, according to a city utilities official.

The underground 12-inch water main broke about 9 p.m. at Griggs Lane, a cul-de-sac off Laurel Street, Napa Utilities Director Joy Eldredge said. The rupture made a large sound, “like a boom,” Eldredge said, and the pressurized water quickly bubbled up through the asphalt.

City crews responded to the area and shut off water flow at about 9:40 p.m. to the broken section, cutting off water access to 14 area customers.

Eldredge said the rip likely occurred because the pipes were built in 1944. Nothing struck the water main.

“This is the nature of some of these older cast-iron pipes,” she said.

In order to fix the ripped section of pipe, crews worked throughout the night. They removed the broken pieces, installed a new 10-foot section of pipe and disinfected the area using chlorine.

As of early Thursday afternoon, workers were still flushing water through the system to ensure it is clean.

Crews turned the water back on at 1:34 p.m., Eldredge said. After that the water was sampled for testing, which can take about a day, to ensure it is once again safe to use for drinking and eating. Until the tests are complete, affected residents should boil any water as a precaution, she said, adding that they had already been notified.

In order to lighten the load on residents, the city dropped off 24 water bottles to each household. City staff were also assessing Thursday whether there were any damages caused by the ruptured water main.