LOS ANGELES (AP) -- The rupture of a nearly century-old water main that ripped a 15-foot hole through Sunset Boulevard and turned a swath of the University of California, Los Angeles into a mucky swamp points to the risks and expense many cities face with miles of water lines installed decades ago.
Much of the piping in the country dates to the first half of the previous century, with some installed even before Theodore Roosevelt was in the White House.
Age can take a toll. There are 240,000 breaks a year, according to the National Association of Water Companies. a problem compounded by stress from an increasing population and budget crunches that slow the pace of replacement.
The group says 45 percent of water pipes in the U.S. are in poor shape, and the average age of a broken water main is 47 years.
In Los Angeles, a million feet of piping has been delivering water for at least 100 years, officials say.
When taps are running and swimming pools are brimming, no one pays attention to water lines, typically invisible underground.
But with the passage of time the country has reached a point where vast amounts of piping is wearing out at about the same time, said Greg Kail of the nonprofit American Water Works Association.
“Water pipes last a long, long time but they don't last forever,” he notes. “There is a lot of pipe in the ground and there is an enormous expense, collectively, in replacing it.”
The 30-inch pipe that burst Tuesday near UCLA sent a 30-foot geyser into the air that eventually sent at least 8 million gallons of water onto campus in the midst of California's worst drought in decades. Repairs could take days.
At one point, water was gushing out of the break in the riveted steep pipe at a rate of 75,000 gallons a minute. The amount of water spilled could serve more than 52,500 Los Angeles Department of Water and Power customers for a day.
The pipe had been worked on before. While the cause of the break remained under investigation, Mike Miller, a district superintendent for the city Department of Water and Power, said the crack occurred near a connection where the 93-year-old water main joined a pipe installed in 1956.
The pipe must be dry for repair work to begin, but on Wednesday leaky valves above the break allowed water to continue seeping in. Shutting off valves and pipes creates the risk of more ruptures in the 7,200-mile system, especially on hilly areas in and around campus.
The reputation of Los Angeles for producing the next new thing in style and culture doesn't extend to its creaky infrastructure. The city is decades behind in repairs to cratered streets and sidewalks and some of its water lines have been around so long that William Mulholland could have seen them going in.
Mulholland is the father of the Los Angeles Aqueduct, completed in 1913, that brings in water from 200 miles away and spawned a development boom that birthed the nation's second most populous city.
Recent years have seen a series of pipe breaks that have prompted promises to speed up repairs and pipe replacements. There's been talk of a water rate increase to speed the work.
In 2009, several dozen breaks _ one that sent up a gusher the size of Old Faithful _ flooded streets.
There was disagreement on the cause but one independent investigation found the culprit was a city law that rationed lawn watering for conservation. With residents restricted to watering only two days a week, pressure fluctuated in the city's water system, straining aging and corroded cast iron pipes until they burst, it concluded.
Cast iron pipes make up 65 percent of the city's water distribution system.
The UCLA flood left people stranded in parking garages and sent water cascading into the school's storied basketball court, Pauley Pavilion, less than two years after a $132 million renovation.
Despite the rupture, no utility customers were without water. No injuries were reported.
UCLA officials said six facilities were damaged. The flooding hit the part of campus that is home to its athletic facilities, with the greatest danger coming in a pair of parking structures that quickly began filling with water.
More than 730 vehicles were in two subterranean garages that flooded, and about half the vehicles were totally submerged, UCLA spokesman Ricardo Vazquez said.
Many students took the flooding in stride, walking calmly across campus with their backpacks in ankle-deep water.
Post-doctoral student George Saddik stood Wednesday outside one of the garages where his SUV was parked on the bottom level.
Saddik, who had to spend the night at the home of a brother-in-law, said he was less concerned about his vehicle than about how he would commute to his home 50 miles away.
“I have insurance so I'm not sweating it,” he said.
Associated Press writers Raquel Maria Dillon, Christopher Weber, Bob Jablon, Beth Harris and Andrew Dalton contributed to this report.