In drought, a city's über-plumbers plug leaks
Meet George Kunkel Jr., Philadelphia's king of leaky pipes.
We're not talking daily drips here, or even the toilet that won't stop running. Mr. Kunkel is after the real thing: Rosie the Riveter-era water mains that have finally cracked under the pressure of time.
During this drought, Kunkel's mission has taken him to one of the city's seedier neighborhoods. Just outside Bo's Tire Repair, Kunkel has donned a set of headphones that seem to be coming out of a hydrant. He is hearing what sounds like a bathtub draining, but is actually water being forced out of a broken pipe. "It's a leak all right," he says.
Unfortunately, this is just one missing drop in the bucket. The City of Brotherly Love, with possibly the oldest water system in the nation, cannot account for about 85 million gallons of water a day, or about 30 percent of what the city sucks up from the Delaware and Schuylkill Rivers. In fact, almost every major city in the East is faced with this problem: US water systems lose about 15 percent of the 40 billion gallons of water per day that flow through the municipal pipelines, estimates the United States Geological Survey.
"Leakage is one of the major problems for the US water supply," says Earl Spangenberg, a professor at the University of Wisconsin at Stevens Point and an authority on water issues. "Almost every metro area has this kind of problem. What determines the extent of the problem is the age of the distribution network and the fact that cracks and leaks happen in any system."
In the past, many municipal water systems didn't worry about leaks. They reasoned that it was more expensive to send a crew out to find cracks and pinholes than to lose some water. "When it rains, they quit worrying about it," says Tim Brown, a consultant at Heath Consultants in Houston. "For some it's only during a drought that they look for leaks: We call it the 'hydro-illogic' cycle."
Mr. Brown says municipal water systems should check their math. He estimates that it costs about $150 per mile of main to find a leak. If a system is losing 20 percent of its water, it may be costing as much as $100,000 per year in water that could be sold.
When a water company does find leaks, Brown says, more than half the time the leak is on the service line leading from the main to the residential user. In some water systems, repair of that leak is up to the homeowner. In fact, in Philadelphia, homeowners are given 10 days to stop such a leak, or their water service may eventually be shut off. Repairing the line can cost thousands of dollars.
"We often get a call from the resident who says, 'There must be some mistake here,' " Kunkel says. "They are truly shocked when they find out there is no mistake."
Kunkel says that water suppliers are now starting to question if they should spend more money maintaining those service lines since they represent about 55 to 60 percent of the leaks. This may entail offering insurance to homeowners. "We are looking into channeling our funds more strategically," he says.
Although these leaks are important, Kunkel is also trying to stop much larger deluges with some success. Ten years ago, the city could not account for 130 million gallons of water per day, or almost 50 percent of what it used. "We're making headway," says Kunkel, whose official title is "chief, load control center."
Kunkel, a trim man, looks more like an accountant than a plumber. But trained as an engineer, the sandy-haired manager is adept at using everything from giant clamps, which act as Band-Aids on pipes, to the most sophisticated electronic equipment like hydrophones which can locate a water leak under the street.
To find the leaks, Kunkel studies water patterns the same way that Wall Street analysts study stock charts. Normally, residents start their day with a shower, which together causes a sharp spike in water demand. By 7 a.m., however, use drops until 8 p.m., when dishwashers push it back up again. In the early-morning hours, demand is a trickle.
But that is not true in this section of 1,600 houses in West Philadelphia an area of abandoned houses, a nonworking trolley line, and heavy truck traffic. Using a meter, he knows that water usage in the residential area is 400,000 gallons a day, all day. His teams have already found some leaks, but so far, they haven't amounted to much.
The problem could be in the age and quality of the water mains. The Philadelphia water system was begun in the late 1700s, when hollowed-out trees carried water from a reservoir. Needless to say, they leaked, and by the 1830s, the city had replaced them with cast iron. However, half of the water mains in the city still date back to between 1870 and 1920. They were laid when Philadelphia was growing quickly as a manufacturing center. Today, "they are the worst offenders," says Kunkel.
Other factors are at work, too. Water mains fail because of the vibration of traffic and quick changes in temperature. More than 50 percent of failures take place from December to February.
Sometimes, it's not just the pipes. For example, the city of Bethlehem, Pa., has been losing about 30 percent of its water since 1948. The city has performed water audits and tried to find leaks. Now, Kathy Reese, director of water and sewer resources, suspects faulty meters. The city is asking every resident to send in information from their meters, telling them "you might be overcharged for your water."
It's not unusual for cities to be unsure how much water they are losing. "We have not been strong accountants in terms of tracking water and having systems in place so we can track loss," says Kunkel, who's also chairman of the leak-detection committee of the American Water Works Association, which represents 4,000 utilities that supply 180 million North Americans.
International efforts to track water leaks received a big boost in 1995, after a drought hit the United Kingdom. The British found that even small efforts, such as turning down the water pressure at night, cut down on water loss. They also developed new technology, such as a "torpedo" that pulls a new water main through a leaking one without ripping up a street.
But sometimes it doesn't take a Sherlock Holmes to find a leak. The owner of Bo's Tire Repair, Linwood Geiger, had water in his basement when one of the pipes in front of his shop burst last year. Now, he points to a small dip in the road. Semi-trailer trucks, he says, hit the dip, and the vibration rattles his windows.
In all, he's seen the water pipes in front of his shop repaired six or seven times. "I sit on the stoop and watch them dig up the road," he says of the various utilities. But "that same hole comes back."
Kunkel just listens. A subsequent investigation by the Water Department finds that what Mr. Geiger says is true, but they have also found that someone may be using the fire hydrant illegally, which can cause a pipe to burst.
It goes to show that there's a long list of reasons for the leaks. Says Kunkel ruefully: "You're never going to stop all the leaks."
Average household water use amounts to 127,400 gallons annually, 350 gallons daily.
The US has freshwater resources totaling about 660 trillion gallons. Americans tap into about 341 billion gallons of those resources daily.
Of the amount withdrawn in the US, only 1 percent is used for drinking water. About 41 percent is used for agriculture, 39 percent for hydroelectric power, 6 percent for industrial use, and 6 percent for household purposes.
The distribution network for large US water systems is made up of about 600,000 miles of pipes.
Source: American Water Works Association