The lack of information raises questions about water quality reports issued by utilities. Federal rules require them to test water in places at high risk for lead contamination. But if testers don't know where the lead pipes are, they can end up sampling lower-risk sites and potentially understating the lead levels.
"This is nuts," said Dr. Jeffrey Griffiths, a professor of public health and medicine at Tufts University and a former chairman of an advisory board for the U.S. Environmental Protection Agency's Drinking Water Committee. “Given what we know about lead, we need a national mapping in my view of what’s out there. … We just have giant holes when it comes to our understanding of how much lead is in the ground.”
For months last year, the question seemed to hang over Flint: How could so many homes show high levels of lead in the water when the samples tested and submitted by the city to state regulators indicated perfectly acceptable readings? The answer, in part, is that the city didn't know where its worst lead problems were, and it made assumptions about where to sample without necessarily knowing where all its lead water lines are buried and to which homes they are connected.
In an age of digital technology, including GPS mapping, many communities including Detroit, Lincoln Park and Southfield still keep their water service connection records on manila-colored index cards, handwritten in pencil by installation crews decades ago.
Some have begun digitizing them for searching purposes, and others are attempting to map them. Researchers from the University of Michigan Flint recently digitized more than 45,000 cards from Flint's water system.
At issue are the lead service lines, the small pipes that connect homes and businesses to the larger water mains under the street. Now, they are mostly made of copper, but before 1950, many of them were made of lead, which can leach off the pipe and into the water, potentially poisoning users.
The Free Press' survey of almost two dozen communities found many across metro Detroit lacked precise records, the result of record-keeping practices that date back decades, before computers and before the dangers of lead in drinking water were fully known.
"Most of those services were put in 1940 to 1945, and when they put those down initially, they didn't put down what material they used," said Tom Wilson, Livonia's water and sewer supervisor. "We don't know for sure where they are."
The record keeping makes even quantifying the problem on a nationwide scale difficult. Most estimates place the number of lead service lines between 3 million and 10 million, though Griffiths calls those figures "best guestimates."
"Three (million) to 10 tells you nobody knows," he said.
The American Water Works Association pegs the number at 6.1 million, based on a peer-reviewed study the group will release soon.
"That's down from the original number going back a couple of decades, which was over 10 million," said Tracy Mehan, executive director for government affairs for the trade group, which represents more than 4,000 people in the water industry. But Mehan added that the figure could miss some.
"That 6.1 million isn't the result of hard inventory," Mehan said. "We haven't created a national database."
Replacing a lead service line can cost a utility between $250 and $3,200, while the homeowner's share of the bill can range from $450 to $10,000 depending on how much digging is involved. Even using the conservative figure of 6.1 million such lines across the country, the bill easily reaches into the billions.
To be certain, no one is suggesting that a public health crisis such as Flint's is a common threat: Water systems routinely use corrosion control treatment that helps prevent lead from leaching into people's tap water. The Flint crisis arose because for more than a year and a half, no such corrosion controls were used when the city switched water systems.
Still, the absence of maps or lists of homes with known lead pipes makes knowing where to test for lead an educated guess at best.
Under current federal rules on testing for lead, municipal water systems must take samples from taps in homes and buildings "that are at high risk of ... contamination." How many and how often depends on the system's size and the levels of lead previously detected.
The rules require each water system to identify an adequate number of sampling sites for copper and lead, a process that is supposed to include determining whether lead is present in lines. But even the EPA has acknowledged in the past that those evaluations didn't result in utilities assessing their lead pipes system-wide.
Questions also have been raised as to whether the EPA's rules for selecting sample sites, such as using those with copper pipe and lead solder that may release only low levels of lead, are outdated.
In fact, after Virginia Tech University researcher Marc Edwards raised questions about Flint's sampling, the state Department of Environmental Quality found that of the 324 sample sites used to monitor lead in Flint over the years, only six could positively be determined last November as having a lead service line. Federal rules also require municipalities to attempt to draw samples from the same list of sites from year to year to maintain consistency but Edwards found that in Flint's case only 13 of the homes with the lowest lead levels sampled in 2014 were resampled in 2015. Water officials say it can be difficult to resample some homes without the homeowner's cooperation. And new owners aren't always as willing to cooperate with water testers seeking samples.
Mapping lead service lines can depend on the resources available to the city.
“Most utilities ... have made some kind of an attempt at an inventory. (But) there are varying levels of sophistication,” said David Cornwell, a former Michigan State University professor and founder of Environmental Engineering & Technology, a water infrastructure consultancy in Virginia.
In Boston, for instance, all the lead lines have been mapped. Residents can go to the website of the Boston Water and Sewer Commission, enter their address, and see a map of their neighborhood appear. Homes with lead service lines are colored yellow to make identification easy.
Federal rules are being looked at to determine whether there is a better way of encouraging water systems and their customers to take on the task of locating and replacing all the lead service lines, to eradicate any lingering problems. A proposal before the EPA would set targets to have all lead lines replaced by 2050.
Utilities are generally responsible for the line up to the property line but from there the cost belongs to the homeowner. For both, the cost and the scope of the problem makes replacing the lines a long-term effort at best. And there is some evidence that some partial-line replacements can result in even higher lead levels, at least in the short term, because the construction work can disturb lead that had been settled for years.
Why lead?
Lead was used for centuries in plumbing because of its resistance to pinhole leaks that commonly form in other metals over time. It wasn't until the 20th Century that the health risks of lead plumbing became widely known and a decade-long effort to eliminate it from water supply systems began.New lead service lines have been banned since the 1950s. The EPA banned solder that includes lead and has been gradually reducing the amount of lead that can be used in faucets, shower heads and other plumbing fixtures.
Lead is also present in other ways. While it is too soft to be used to make large water mains, it was used to seal joints on those pipes before rubber gaskets became common. Lead was commonly used most often on the service lines, which are typically an inch in diameter or less.
But finding those lines is hard.
In the 1990s, the Detroit Water and Sewerage Department hired an engineering firm to identify the lead lines in the city. The firm concluded that there were about 100,000 of them within the city limits, but that didn't involve physically locating each pipe.
"We project that any home built before 1946 has a lead pipe in it," said Darryl Lattimore, a member of the executive team in the water department.
Because of Detroit's aggressive demolition program in recent years, it's unclear how many of those homes remain.
"We don't have anything that identifies all the homes," Lattimore said. "We would probably have to do a manual search."
Like many older cities, Detroit still keeps records from that era on index cards, though the city hopes to digitize and map them, Lattimore said.
Despite the high number of lead lines, Detroit has been able to meet federal standards by treating its water with phosphates, which controls pipe corrosion, Lattimore said.
The Oakland County Water Resources Commissioner's office operates water systems in 14 communities, but doesn't have records showing which homes are connected with lead service lines, spokesman Craig Covey said.
Most older cities face similar difficulties.
"We don't know for sure where they are. There aren't that many in Royal Oak," said Jeff Pierce, Royal Oak water and sewer supervisor, noting that the city rarely finds them when replacing water mains. "Records from homes that far back are just really rare."
Royal Oak, like most cities, replaces lead lines it finds.
When Southfield began connecting residents to water mains, the installation crews would write down the specifics on manila file cards. The cards, which number about 20,400, list the address, the order date, the installation date and some notes about the installation, often including hand-drawn diagrams of where the line enters the house. But the cards don't necessarily note whether the pipe is lead.
"They are really dusty and up until the 1980s, they were all handwritten," Southfield Public Works Manager Larry Sirls said. "We took these and scanned them in and we can search them now."
Sirls said there are about 45 or 50 known lead service lines that the city tracks. Those can be looked up on the city's computer system. But occasionally, the city finds others it didn't know about.
In those cases, Southfield, like most cities, replaces the city portion of the pipe, from the water main to the shut-off valve near the sidewalk, and advises the homeowner about the lead line.
Lincoln Park is an older city with more lead lines and tracks them on index cards. Officials said they would like to use newer technology, but the city has been so cash-strapped that, like Flint, it was under an emergency financial manager until December.
"Lincoln Park does not have funding enough to map it out," John Kozuh, director of public services, told the Free Press, adding that the information should be entered into a geographic information system that includes roads, sewers and other infrastructure but "we do not have funding for this either."
Cities that built up after 1970 have far fewer lead lines. Crews might occasionally find one in an old farmhouse, but those are rare.
"If we do have them, we don't know about them," said Paul Trosper, Troy's superintendent of water and sewer. "I've been here for 29 years and I can recall three."
Troy removes the city's portion of the pipe as it finds them, as does Clinton Township.
"We are not aware of any. We don't have any records of them," said Mary Bednar, director of public service in Clinton Township. "If we do run across one, we are required to replace it immediately."
Across the state, other cities have made more progress with their lead pipes.
In 2004, the City of Lansing committed to spending $30 million to replace its 14,000 lead service lines. There are about 500 left in the city and those should be gone by 2017, city officials said last month.
Other cities have begun tackling the problem as well. Grand Rapids officials say they have identified all of their 17,000 lead service lines and cataloged them digitally for searching purposes.
But Cornwell, the water infrastructure consultant from Virginia, said even when system officials think they know where their lines are, there is plenty of room for error, as utilities "go in (to sample or replace a line) thinking there are lead lines there and there aren’t. Or vice versa.”
Replacing the lead lines is still seen as the most thorough means of addressing any potential problems. But it's a project that would take decades, experts said.
“There’s a huge problem with political will," said Griffiths from Tufts University. "If al-Qaida decided to poison our children, we’d be all over it. … Instead, we have neglected our own infrastructure. It boggles the mind that we have this need for knowing about lead (in our water supplies).”
©2016 the Detroit Free Press Distributed by Tribune Content Agency, LLC.
