A nearly century-old water main burst in the Hollywood Hills in the predawn hours Wednesday, cracking sidewalks and pavement and submerging cars as at least 100,000 gallons of water spewed into a residential neighborhood.
Much of the flooding had subsided by mid-morning, but customers near the break in the 6400 block of Dix Street went without water until just before 9 p.m. when repairs were completed, according to Los Angeles Department of Water and Power spokeswoman Kim Hughes.
City crews are expected to repair the damaged roadway on Thursday.
One-fifth of Los Angeles' water mains were installed before 1931 but account for close to half the pipes that are most prone to cause damaging leaks, an analysis by the Los Angeles Times has found. Those deteriorating pipes pose a major financial problem for the L.A. Department of Water and Power and city leaders.
The cast-iron pipe that broke Wednesday morning was installed in 1926 and hadn't had a leak in the last 10 years, said Marty Adams, the DWP's water systems manager.
DWP engineers assign a letter grade to pipes to prioritize for replacement. About 6% of the system have grades of D and F, denoting the most urgent need. The pipe that broke Wednesday had a grade of C.
Resident Chris Mora said Wednesday morning the deluge was more violent early in the morning. He held his 10-month-old son, Sebastian, while surveying the damage before him.
"I woke up at 2 in the morning and thought there was a sound of rain," he said.
The Los Angeles Fire Department was on the scene at 4:48 a.m., said Capt. Jaime Moore. Several vehicles were submerged in a parking lot that sits below street level.
Miller Lee rushed to Hollywood Hills after he saw the apartments his father owns on the news. The street was flooded, and his family's complex looked to bear the brunt of the destruction.
At least eight people live in the four units damaged by the flood, Lee said. Four cars were submerged in the lot between the two complexes, and he worried there was more destruction inside the garages yet to be discovered.
Lee said his family stored classic cars, including a 1954 Triumph convertible, antique Italian furniture and pricey Persian rugs in the garages.
"I'm devastated," Lee said, standing in the now-drained parking area. "I feel bad for our tenants."
One of those tenants is Austin Wood, who said he woke up early Wednesday to a police officer pounding on his front door. He discovered the parking lot filled with water and his Buick LeSabre submerged in a murky pool.
His roommate Nick Brightwell said there was a storage unit under the apartment where he'd just stored family mementos.
"Perfect timing on that," he said.
The DWP's Adams said the extent of damage to the pipe and its specific cause weren't immediately clear.
Los Angeles' system of water pipes has averaged nearly 1,200 leaks a year since 2010, according to The Times' analysis of DWP data.
Water main leaks and breaks occur on average about three times a day across the city, DWP officials said last year.
Several Hollywood neighborhoods were among those with the largest number of leaks. There were 48 pipe leaks from Jan. 1, 2010, to Nov. 29, 2014, in the Hollywood Hills.
An 82-year-old cast-iron main nearby in the 2000 block of Ivar Avenue ruptured eight months ago.
Pipe age, water pressure, soil quality and leak history are several factors that contribute to water main breaks.
Adams said Wednesday's break was "unfortunate but not a disaster" as the leak was relatively localized.
"The unfortunate part was that any customers were impacted," he said. "But this is an indication of what's going on in an aging city."
Los Angeles Times staff writer Ben Poston and Matt Hamilton contributed to this article.