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Title image: The scene at the Replacing Lead Pipes for Clean Drinking Water event in Milwaukee, Wisconsin on 8 October 2024. (Credit: )

The U.S. Environmental Protection Agency (EPA)  this month that it will require utilities to replace all lead drinking water pipes serving customers in the country within the next decade, marking the most aggressive regulation on lead in drinking water to date.

“This new rule is part of a progression of not just trying to treat a symptom but going back to the source and removing that material from our everyday use,” said Julie Korak, assistant professor in the Department of Civil, Environmental and Architectural Engineering.

Julie Korak

The rule comes a decade after the , Michigan, when the city’s failure in water treatment exposed nearly 30,000 schoolchildren to lead, a neurotoxin that can impact children’s brains and nervous systems.

The EPA  that there are more than 9.2 million lead service lines—underground water pipes that serve water from public pipes into properties—in communities across the country. If a structure was built before 1986, there's a higher chance it has a lead service line, Korak said. To support this effort, the EPA has announced $2.6 billion in new funding. While replacing all these pipes will be a huge undertaking, it needs to be done, she added.

“We have to recognize that there are disparities where the presence of lead service lines disproportionately impacts disadvantaged communities. To promote equity across our country in terms of what kind of environmental hazards we're exposed to, it's important to address this disparity.”

The municipal government of Boulder recently announced that the city has  after conducting a two-year inventory. Denver Water, the utility serving the city, has , about a third of the estimated total, by July 2024.

As water utilities around the country race to identify and replace lead service lines, ���Ҵ�ý�ƽ������ today sat down with Korak to chat about the new rule and how individuals can protect themselves from lead in water.

Why is lead in water such a concern?

Lead is a toxic element. Unlike some other contaminants of concern, there is no safe level of lead, which means that there's no concentration or dose below which we don't experience adverse effects.

When lead from water pipes leaches into the water that we consume, it can have harmful toxicological effects, especially on children, such as low birth weight and adverse cognitive impacts. Exposure to lead during their developmental stages can be particularly adverse to their health. While it will be costly to replace all the lead service lines, the EPA analysis shows that benefits outweigh the cost in this case.

How does lead get into the water?

Lead has been used as pipe material for centuries, dating back to Roman times. It’s a soft, easy-to-mold material, which makes it ideal for shaping into durable pipes. But over time, the pipes can corrode, dissolving lead into the water. In addition, as water flows through the pipes, it can dislodge small particles of lead, which are then carried by the flowing water to consumers.

What is being done currently to minimize the impact of lead pipes?

Under the Safe Drinking Water Act, the Lead and Copper Rule has been in effect since the early 1990s. The EPA requires utilities to take steps to test for lead in drinking water, identify homes with lead service lines, and adjust water treatment methods to decrease lead release if the lead levels are above a certain threshold.

However, there is a recognition that as long as these lead service lines are present, they pose a potential risk, and a long-term plan to remove this potential risk is in the best interest of public health.

This new regulation is not to say that the previous methods have not worked. Tests have shown a decrease in blood lead levels across the country over the last 50 years. This decrease comes from a combination of different regulations to remove lead from not only water pipes, but also gasoline and paint.

How are lead pipes being replaced?

Replacing service lines will be a continuous effort with dedicated teams for impacted communities. If you start doing some of the math for average-sized communities, utilities need to be replacing a line every other day, for the better part of a decade, to make it happen. Larger metropolitan areas would likely need a more aggressive schedule.

One of the first challenges is determining how many pipes need to be replaced and where those pipes are located. Some communities may have good records of what pipes were used during construction. Some may have almost no records at all. In those cases, utilities will look at when buildings were constructed and what materials would have most likely been used at that time. They may visit sites and dig up a portion of the front yard to inspect materials, or request to go into a basement to see what kind of material is coming into the home.

Most utilities will replace lead service lines with copper pipes. Although also a metal, copper does not have the same adverse health impacts. From a regulatory perspective, the concentrations at which we become concerned are orders of magnitude different between lead and copper. For lead, concentrations above 10 micrograms per liter will trigger action. The action level for copper is just over one milligram per liter.

What can individuals do in the meantime to protect themselves from lead?

If someone is concerned that they might be exposed to lead from service line, there are filters that are certified to remove lead, both the dissolved lead and the small particles. It's important to purchase the filters from a reputable vendor and make sure that it's certified by NSF for lead removal. Larger utility companies will likely have a resource page on their website that recommends .