The push to remove lead pipes is on. Thousands of water systems still don’t know where theirs are

Kathryn Pilgrim knew the century-old Victorian she bought in Dunkirk, New York, came with old plumbing. She replaced pipes she suspected of containing lead and later installed a kitchen filter designed to remove heavy metals.

But six years after buying the house, she still can’t be sure that her tap water is lead-free because she doesn't know what material was used for the pipe that runs under her front yard and connects to the city water supply. Dunkirk is nearly two years behind schedule on an inventory that would give Pilgrim and other residents that information.

Dunkirk, which supplies water to about 5,000 homes and businesses, is one of more than 1,300 public water systems cited by the U.S. Environmental Protection Agency for failing to meet an October 2024 deadline to hand in an inventory of the water lines that could be leaching the heavy metal into Americans' drinking water, an Associated Press analysis of the agency’s enforcement data shows.

Roughly 6,300 water systems serving 3.8 million Americans have still not submitted a required list of how many lead service lines remain in use.

Those inventories are critical for cities to replace all lead pipes by an upcoming 10-year deadline. Failing to document the lines also means residents won't know if their homes have a potential source of lead exposure.

Pilgrim, a special education teacher who has fostered teenagers, had been educated on the dangers of lead, especially in paint. The colon cancer survivor's concerns extended to her drinking water.

“I just thought there was some stuff in the water that might not be great,” she said.

Officials with the city of Dunkirk did not respond to requests for comment.

Lead pipes are abundant across New York and many communities around the country with older infrastructure. The city of Buffalo’s data shows 45% of its service lines — which connect homes and businesses to the water supply — are made of lead, the third-highest rate of any major city. The city of Fredonia, which neighbors Dunkirk, reported 28%.

Lead is a neurotoxin that can stunt children’s development, lower IQ scores and increase blood pressure in adults. Roughly 4 million homes and businesses are still connected to water utilities via lead pipes, according to the EPA’s latest estimate.

How much lead is entering the building depends on factors like the water chemistry and the pipe's condition, but lead service lines remain the most significant source of the heavy metal, according to the EPA .

The EPA has touted its work on lead lines as a key environmental win. About three-quarters of the drinking water enforcement orders issued by the EPA since President Donald Trump’s return to office were related to missing inventories.

Most water systems with missing inventories are small — 84% provide drinking water to fewer than 500 people, the AP analysis shows. Many are small housing developments, mobile home parks or schools.

The EPA said it turned to enforcement only after efforts to help water systems comply were unsuccessful. Utilities need the inventories to prepare for a 2027 deadline requiring most drinking water providers to replace their lead lines within 10 years, the agency said. The Trump administration has also defended that aggressive deadline , enacted under Biden, in court.

Rob Hayes, a senior director with Environmental Advocates of New York, said it is a rare environmental regulation the Trump administration has not sought to scrap.

“It speaks to the universal popularity of getting lead out of drinking water,” he said.

About 3,500 water systems reported they don’t know what their service lines are made of. One in five service lines nationwide were reported as having unknown materials.

Many utilities are racing to identify unknown pipes by next year, when they must begin replacing them.

In Chicago, home to the most lead lines of any city in the country, crews are working block-by-block, digging up the pipes that branch off from the utility's main line. The city still doesn't know the material of close to one in 10 service lines. So in those cases, crews may have to excavate them to check the material, said Patrick Schwer, the city's water quality director.

“We are digging through every single piece of information that we have associated with every single service line trying to find any indications of the material,” he said. “We’re scouring millions of work orders, trying to pull at little threads of information.”

Lead pipes for public water date as far back as the late 1800s and were prevalent all the way to the 1950s. Lead was a preferred material at the time because it was resistant to corrosion, and as a result, the original lines remain in use decades later.

Chicago advises residents with unknown lines to assume they are made of lead if their building predates 1986, when it was banned under the U.S. Safe Drinking Water Act.

Records of the installations were often lost, incomplete or illegible . Lapses in recordkeeping have made it difficult for some utilities to complete their inventories, said Joshua Klainberg, senior vice president with the New York League of Conservation Voters.

Still, Klainberg said, leaving residents in the dark about whether they should take precautions by not submitting an inventory at all is “unforgivable.” Even an incomplete inventory can alert people they may have a lead service line, allowing them to take precautions such as running the tap, using filters — the highest-quality of which can remove most lead — and cooking only with cold water, he said.

For utilities, not knowing what is in the ground will carry an even stiffer consequence beginning in 2027. Starting then, they are required to replace 10% of lead water pipes each year, usually with copper or plastic pipes . But lines made of unidentified materials will be included in that target, said Erica Galante-Johnson, a lead policy analyst with the Environmental Policy Innovation Center.

“The more unknowns, the more lines a system needs to replace every year,” Galante-Johnson said.

And each replacement is expensive, usually costing between $8,000 and $15,000 , according to EPIC.

In Chicago's case, “the city is actively going after every single dollar that we can,” from the federal and state governments, Schwer said. The city still needs to replace about 393,000 lead service lines.

Most funding for identifying and replacing lead pipes comes from the 2021 bipartisan infrastructure law , with states distributing it. This is the final year of dedicated federal funding for lead projects, though previously allocated money will continue flowing to communities.

Water systems without an inventory will fall even further behind as national efforts shift toward replacements, Hayes said.

“If they can’t even get an inventory together, how the heck are they going to get the resources and the manpower and the kind of coordination between governments together to actually get workers out on the street and dig these pipes out of the ground?” he said.

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