The drought has Californians feeling the pressure to conserve water, but some century-old pipes may be thwarting these efforts. The government’s bank account is also running dry trying to fix it.
Leaking water pipes lose an estimated ten percent of the bay’s potable water every year.
Many of the system’s pipes have aged well beyond their expected retirement, causing an average of three breaks every day in the entire Bay Area and tens of millions of gallons of water lost. Local water companies have beefed up their proactive replacement efforts, but with 5000 thousand miles of pipes from the north bay to San Jose, it’s tough to keep up.
The Investigative Unit
Old City, Old Pipes
San Francisco has many historical buildings- and that means historical pipes. Out of the 1,200 miles of pipe running under its streets, about 20 percent of that is over a century old.
JB Alegiani’s 120-year-old San Francisco house had a leak earlier this month from the water main that dates back to 1883. He didn’t have full water pressure for several days while crews fixed it.
“Here in San Francisco, we definitely have an aging infrastructure,” Alegiani said. “And now that we have a drought and it’s the new normal, we’re going to have to really change our policies as to how we look at water.”
According to the city’s public utilities company (PUC), leaks like that at Alegiani’s house cause the loss of 3 to 8 million gallons of San Francisco water every day. That’s a rate of 4 to 8 percent of the 70 million gallons of water San Franciscans use each day.
NBC Bay Area followed a repair crew for a day as they fixed leak after leak.
At one point, crews dug out a broken cast-iron water main first installed in 1863- pipe first put in the ground during the Civil War.
“Some of those pipes are in pretty good shape, but a lot of them are brittle,” said Katie Miller, who oversees water distribution at San Francisco PUC.
Miller says the PUC replaces 15 miles of pipes each year at a cost of $40 million. Miller says this rate will have to get more aggressive soon.
“If we don’t invest, it will cost us a lot more in the long run,” Miller said. “Even though we have 100 to 120 breaks a year, it’s far lower than a lot of other cities.”
Across the bay, East Bay Municipal Utilities District oversees the delivery of water to 1.3 million customers in 28 different cities. The system has 4,200 miles of pipe, more than three times the amount in San Francisco. Last year alone, East Bay MUD had 800 breaks.
“One of our goals is to keep that leak rate stable,” Xavier Irias, Director of Engineering and Construction, told the Investigative Unit. “With an aging population of pipe, that means we really need to keep on the pipeline replacement.”
The pipes are made with different materials, depending when they were installed.
According to Irias, the oldest pipes in the system are made of cast-iron and were installed in the 1800s. Now, some 150 years later, they cause the most leaks of any type in East Bay MUD’s system.
“Half of the leaks are cast-iron even though it is only about one third of the total population of pipes. That’s partly just because it’s older. It’s prone to corrosion,” Irias said.
However, the newer pipes have problems too. In the 1950s and 1960s, the East Bay switched to asbestos cement.
“The cast-iron, while it may be breaking, it’s older, but the [asbestos cement] doesn’t seem to last nearly as long as cast-iron,” Irias told the Investigative Unit. “We do anticipate those leak rates are going to go up with time and actually that’s what we’ve seen in the last few years as we started taking a really close look at [asbestos cement].”
San Jose’s pipe system is younger but still prone to leaks. The area’s largest provider, San Jose Water Company, had 182 breaks last year. On average, the broken pipes were 55-years-old.
East Bay MUD has a team of six leak investigators whose only job is to proactively uncover leaks using new technology. The teams use sound-sensitive machines to precisely detect where unseen leaks start underground in order to replace them sooner and minimize water loss.
Irias says the drought seems to be causing even more leaks that can be hard to detect. He says a drought can cause the earth to contract and that can cause abnormal stress on the water delivery pipes.
“As that soil dries, it shrinks. So if there was a pipe, that maybe without the drought, would have failed in the next couple of years, the drought just gives it that extra nudge and it breaks early,” he said.
The sound-sensitive technology can help discover those leaks deep underground.
East Bay MUD currently replaces about 10 miles of pipe per year, up from seven miles per year several years ago. But officials admit they need to start replacing 40 miles per year just to keep up. It costs about $2.4 million a mile to replace water deliver pipes.
Replace Sooner, Pay Less Later
Post-doctorate researchers at UC Berkeley’s Water Resource Center, Jennifer Stokes and Tommy Hendrickson, have been looking for ways to make water systems more energy efficient.
They found that cities can save more money in the long run if they spend on pipe replacement sooner.
“If you were able to maintain lower leak rates, it was going to be more cost effective to dramatically increase your pipe replacement rate than to keep up with these 100-200 a year replacement levels we see across California,” Dr. Hendrickson said. “Eventually somebody is going to have it pay for it.”
“Some of these infrastructure systems are massive,” said Dr. Jennifer Stokes. “It takes a long time to put them in place, and if we go into it without a lot of planning we could find ourselves in a really tough situation in 10 or 20 or 30 years.”
Increasing the replacement rates in cities across the country could cost as much as a trillion dollars in taxes and higher water rates.
“If we don’t start that investment process now we could be in big trouble,” said Dr. Hendrickson.
California congressman, Jared Huffman, is proposing legislation this year to force congress to spend more money on this problem now.
“We’re going to have to try to get to get ahead of this,” said Congressman Huffman, who represents Marin County and serves on the US House Transportation and Infrastructure Committee. “If we don’t update and modernize that infrastructure, we’re going to see massive failures.”