More than 40% of water pipes in the city of Los Angeles are graded C or worse, a Times analysis of the L.A. Department of Water and Power's pipe inventory data reveals.
More than 118,000 of the city's roughly 275,000 pipes received a C or lower grade based on their likelihood to fail and the potential consequences of a break, according to the data, which The Times obtained through a public records request.
Since 2010, the DWP has reported more than 5,200 leaks in water mains that have taken about 110,000 man-hours to repair, The Times analysis found. The average age of the leaky pipes was 73. Nearly two-thirds of the leaking pipes were installed before 1950.
Systemwide, the average pipe age is 58, according to the data.
The average life expectancy of water mains, which make up the vast majority of pipes in the DWP system, is 100 years.
The new information about the decrepit state of the city's water infrastructure comes amid increasing water conservation efforts as the state is seeking to cope with an unrelenting drought and as Angelenos express growing concern over recent major water pipe breaks that have flooded roadways, damaged property and snarled traffic.
"The data confirms what most Angelenos know – which is that we need to invest more in the maintenance and upkeep and repair and replacement of our infrastructure," said Councilman Paul Krekorian.
H. David Nahai, former head of the DWP, said the passage this week of Proposition 1, a bond measure that will fund water projects, will inject new money into the system that can be spent on infrastructure. But he said the bond alone won't solve the agency's aging infrastructure problem. At some point, he said, ratepayers will simply have to pay more to update and repair old, broken pipes.
"Nobody likes rate increases … but they are necessary," Nahai said. "The department needs to make this case to the public."
Councilman Bob Blumenfield said he couldn't say whether he would support increasing water rates without knowing more details, including how that would affect ratepayers in the hottest parts of the San Fernando Valley.
"I am loath to see any sort of increase, but I'm also a pragmatist and a realist," he said.
Leaks are common in pipe systems across the state and nation, and the agency said the number of water main leaks and breaks last year decreased 37% from 2006.
Pipe leaks were reported across the city, but some areas saw more than others, The Times analysis found. For example, neighborhoods in and around Hollywood Hills had more than 500 combined -- about 10% of all the leaks in the city.
More than 5% of DWP's water mains have already reached or passed their expected useful life, The Times analysis found.