Experts, and even some regulators, say existing laws are failing to protect Wisconsin and the nation from harmful exposure to lead in drinking water that leaches from aging plumbing — a danger illustrated by the public health crisis in Flint, Michigan.
At least 176,000 so-called lead service lines connect older Wisconsin homes to the iron water mains that deliver municipal water, according to an estimate by the U.S. Environmental Protection Agency. Milwaukee alone, where 60 percent of the state’s known lead-poisoned children live, has 70,000 lead service lines.
Regulators concede that the Lead and Copper Rule, the 25-year-old federal law that seeks to minimize the danger from these lead pipes and indoor plumbing fixtures, is failing on several fronts:
- Methods for sampling often fail to detect the highest level of lead in a consumer’s home.
- Too few homes are sampled, and those that are may not be in the neighborhoods most at risk.
- The requirement that utilities replace some lead lines when they exceed federal thresholds may actually cause dangerous increases of lead in drinking water.
Lead is primarily leached into Wisconsin’s drinking water by the corrosion of lead pipes and indoor plumbing components.
Health effects of lead include irreversible brain damage in children under age 6 and an increased risk of miscarriage in pregnant women.
Decades ago, when it became clear that lead was one of the worst toxins for the developing brain, U.S. regulatory agencies began to eliminate the heavy metal from gasoline, paint and new plumbing. But the efforts to address the nation’s existing water infrastructure were limited.
Marc Edwards, an engineering professor at Virginia Tech and one of the nation’s foremost experts on lead in drinking water, helped Flint address its massive problem with lead-contaminated drinking water that has poisoned a number of the city’s children.
Edwards said millions of U.S. homes have some lead components in their water delivery system, although he acknowledged “no one knows” the exact number. He agreed with some who have called the widespread risk posed by lead pipes and the astronomical cost to replace them one of the biggest environmental disasters in U.S. history.
Lead hazards underestimated
The American Water Works Association estimated in 1990 that the U.S. water infrastructure had about 3.3 million lead service lines and 6.4 million connections made of lead, many of them installed well over 100 years ago. Wisconsin is one of nine states, all in the Midwest and Northeast, where they are particularly common.
In addition to Milwaukee, several other Wisconsin communities have a high percentage of lead service lines, including Wausau, Wauwatosa and Racine, according to the EPA.
“Although most cities in the United States were moving away from lead water pipes by the 1920s,” a 2008 report said, “it appears that this trend was not universal. National model plumbing codes approved lead into the 1970s and 1980s, and most water systems based their regulations on those codes.”
Another 2008 study found that these service lines account for 50 to 75 percent of lead contamination in public tap water, with most of the remainder due to indoor lead pipes and plumbing components, such as faucets and connections.
The risk of these aging pipes is so high that Madison’s public water utility made the controversial decision to replace not only the portion of the lead service lines that it owned, but also the privately owned portion from the curb stop to the house beginning in 2001. The $19 million program, partially paid for by property owners, is thought to be the first in the United States and now serves as a model for other cities.
The problem posed by lead service lines is likely underestimated in Wisconsin, where census figures show about 27 percent of homes were built before 1950 and 63 percent before 1980.
Miguel Del Toral, a regulations manager at the EPA’s Chicago office, said that after five years of effort, he could only track down written documentation of lead pipes in 113 Wisconsin communities in 47 of the state’s 72 counties. The number of lead pipes outside of these communities is anybody’s guess.
A nationwide EPA survey of 153 public water utilities in 1984 found that “30 percent of the respondents could not offer any estimate of the number of lead service lines remaining in their cities,” according to a 2008 report.
“In the smaller towns, the institutional knowledge about this is lacking,” Del Toral said. “A private well connected to a home can have (lead pipes) too. They are pretty universal. But we have no access to private records.”
In addition, tap water from only a fraction of the 176,000 buildings in Wisconsin on known lead service lines has to be tested regularly as part of the federal Lead and Copper Rule. The law requires utilities to collect water samples from households known or suspected to be served by these pipes.
But, said Del Toral, “If they don’t know about the lead service lines, they may not be sampling at those sites, so unless they accidentally find them, the lead levels being reported might not reflect reality.”
Milwaukee Water Works is currently on a reduced monitoring schedule because of a history of compliance with the federal law; it only has to test for lead in 50 homes every three years. Even before this schedule became effective, the city only had to test 100 homes per year for lead.
Finally, some testing under the federal rule may not accurately reflect consumers’ actual lead exposure, according to a study by Del Toral and another by Edwards. The latter study found that “slight variations from one approved protocol to another may cause lead-in-water health risks to be significantly underestimated.”
“We’ve actually documented a few cases where these instructions caused us to miss lead problems and tell people that the water was safe when it wasn’t,” Edwards said.
Del Toral’s 2013 study found wide swings in lead levels in Chicago households when tap samples were taken 12 or more times during a single day. He concluded that “the existing regulatory sampling protocol under the U.S. Lead and Copper Rule systematically misses high lead levels and potential human exposure.”
Corrosion control can keep lead out of water
A water utility is compliant with the federal law when at least 90 percent of household samples are below the action level of 15 parts per billion (ppb) of lead. Even when utilities greatly exceed the action level, unless it involves more than 10 percent of the samples, no system-wide remediation efforts are required.
If more than 10 percent of samples exceed 15 ppb, a water utility may be required to install or improve corrosion control. This involves adding a chemical, such as orthophosphate, to the water to make it less likely to eat away at lead pipes.
Determining the water treatment method that works best requires money, ongoing maintenance and specialized knowledge about water chemistry. Systems required to use corrosion control include those serving 50,000 or more customers and those in which 10 percent or more of the water samples tested above the federal action level.
In April 2014, when Flint began drawing its drinking water from the Flint River without adding anti-corrosives, blood lead levels spiked in children, inciting a public health crisis, protests and angry finger-pointing. The city has now switched back to Detroit water.
“(Corrosion control) is a complicated subject that has kept water quality experts searching and even arguing for decades,” said Abigail Cantor, a Madison-based chemical engineer who has worked with several Wisconsin water utilities as a technical consultant.
In addition, orthophosphate harms surface water quality. When treated water is released into lakes by the wastewater treatment plant, phosphate contributes to algal blooms, which can cause oxygen depletion and trigger the production of toxic chemicals.
That is one of the reasons that Madison, a city proud of its lakes, rejected corrosion control and instead replaced all of its lead service lines with copper pipes.
Required pipe replacements can boost danger
When a utility is not in compliance with the federal law and corrosion control is ineffective or rejected, it must replace 7 percent of the lead service lines that it owns. Additional replacements are required every year until the utility comes back into compliance.
The utility-owned portion of the service line typically runs from the water main to the curb stop, while the section between the curb stop and the house is usually privately owned.
However, replacing only the utility-owned portion of the pipe, a so-called partial replacement, can have severe unintended consequences: it may increase, rather than decrease, lead levels in consumers’ tap water.
Several factors can cause these lead spikes. One of them is the physical shaking of the lead pipes during the replacement work, which can knock off lead inside the pipe.
“In Chicago, the scale that came off the service line in one event where they cut the line was 300,000 ppb lead,” Del Toral said. “The sediment that came off was 125,000 ppb lead. That would pass straight through a kitchen aerator and would put an infant or child in the hospital immediately, if not worse.”
Lead levels in tap water may also increase after partial replacements due to a chemical phenomenon called galvanic corrosion.
“When old lead pipe is connected to a new copper pipe, the contact of the two metals creates a battery effect that activates lead, so that it enters the water at an accelerated rate,” said Yanna Lambrinidou, one of Edwards’ colleagues at Virginia Tech.
In 2012, a federal Centers for Disease Control and Prevention study reported direct evidence that partial replacements may cause elevated lead levels — not just in drinking water, but also in the bodies of children under 6 years of age.
“Compared with children who had never had a lead service line,” the authors found, “children having had a partial lead pipe replacement were at increased risk for increased (blood lead levels).”
They concluded that “the practice of partially replacing lead service lines as a method to comply (with the Lead and Copper Rule) should be reconsidered.”
Water main repairs also can cause a physical disturbance of the lead service lines, resulting in the same risk of lead scale particles being released into the water. Milwaukee has hundreds of water main breaks a year.
“The water main work is the primary disturbance of the lead lines. That is going on, unregulated, on a daily basis in all major water systems in the country,” Del Toral said. “That’s a very big concern.”
Paul Biedrzycki, director of environmental health for the city of Milwaukee, shared Del Toral’s concern. Fixing water mains is “a tradeoff between replacing aging infrastructure … to ensure the continuity of drinking water service to our population … and a very real public health threat posed by this work,” Biedrzycki said.
Because of the potential danger, a 2014 communications guide by the American Water Works Association urged utilities to notify customers of steps to protect their drinking water whenever nearby water mains are repaired or lead service lines replaced.
Milwaukee Water Works spokeswoman Sandra Rusch Walton said the city takes precautions against lead when it repairs broken water mains by flushing the line and asking homeowners to do the same.
Cantor said that may not always have the desired effect. “Flushing of building water lines is a complicated subject,” she said. “Sometimes it does solve the problem. Sometimes, it riles up pipe wall debris (including lead) and makes matters worse.”
Cantor also said that monitoring for lead in a building is difficult.
“Every plumbing system is different, and it’s hard to predict where the problems lie in the system unless studied in depth — something a property owner can’t do and something a water utility can’t do for a complete city,” she said.
Because of concerns that water main replacement work could cause lead levels to rise, Milwaukee officials in January informed state agencies that the city is temporarily halting planned work on five miles of water mains serving about 500 homes.
New regulations years away, public on its own
A quick fix of the nation’s lead pipe problem is unlikely. Lambrinidou was part of an EPA-convened working group tasked with proposing changes to the Lead and Copper Rule. This group released its final report in August.
One of the group’s major recommendations: requiring water utilities to pursue full replacement of all lead service lines in collaboration with customers.
Lambrinidou estimates it will take at least another five to seven years before any revisions go into effect. Amy Kubly, a water supply engineer with Wisconsin’s Department of Natural Resources, agrees that the EPA ought to move faster, given that the dangers of lead have been known for a very long time.
“I think (the Lead and Copper Rule) is overdue for revisions,” Kubly said. “I’ve heard for years now that they’re working on them, but haven’t heard anything concrete as to what they would contain. Hopefully we’ll hear something soon.”
Until all lead pipes in the water infrastructure system are safely replaced, however, consumers are largely on their own when it comes to protecting their families from lead exposure, Edwards said.
Specific recommendations for residents include testing their water, ideally before starting a family, installing a water filter certified to remove lead and other metals, using only cold water for cooking and never drinking or cooking with tap water that has been sitting in pipes for several hours.
Even Cantor — who has a copper water system, has tested her water and knows she has no metals issues in her house — takes precautions.
“A good rule of thumb is to never drink water that has been stagnating — in any building,” she said. “I fill up a big water jug after I wash dishes at night and put the jug in the refrigerator. That way, I know that I am always drinking water that came fresh from the water main instead of water that has been sitting in the pipes in my house.”
Edwards called for “complete removal of all lead service lines” across the country.
“If we don’t make a decision right now to get these lead pipes out of the ground, when are they going to be removed?” Edwards asked. “They just pose an unreasonable health risk to future generations.”