Pittsburgh Water and Sewer Authority officials gathered with local and state leaders at a lead line replacement site in Bloomfield on Wednesday to celebrate news that lead levels in the system have dropped to 5.1 parts per billion. The agency is now in full compliance with federal and state regulations for the first time since 2016.
Will Pickering, PWSA’s executive director, said the news closes an "unfortunate chapter" in the agency’s history, and thanked customers for their patience.
“Our priority is their health and safety moving forward, and there’s nothing more important than making sure that their water is safe to drink,” he said. “We hope that we can regain their trust in the next few years.”
The Environmental Protection Agency requires PWSA to sample at least 100 homes for lead levels. PWSA sampled 158 homes known to be served by lead lines. Of those homes, no more than 10 percent can exceed the federal action level of 15 parts per billion. (PWSA replaced service lines to homes found to have excessive lead levels during the sampling; those homes will no longer be eligible to form part of the EPA sample set).
Four years ago testing showed PWSA had exceeded that figure, and set off a multi-year effort to overhaul the agency and its infrastructure.
The latest round of water quality testing is the second consecutive sampling period below the federal action level; in January, tests revealed a 90th percentile result at about 10 parts per billion. Officials expect lead levels to continue to drop.
Pickering credits the decline in lead levels to the 2019 introduction of orthophosphate, a treatment that coats the inside of pipes and prevents water from coming into contact with lead or copper.
“It’s used in other cities effectively and it’s proven to be effective here, and working better over time,” he said.
Raanan Gurewitsch runs Geominr, a geographic data and research company that tracks lead and copper rule violations using EPA data. He said Wednesday’s announcement sounds like good news, though he has been concerned about how strongly PWSA links orthophosphate and the drop in lead levels.
“If all you’re looking at is the EPA compliance data, you can’t really claim lead levels are going down around the city,” he said, noting that the EPA data relies on a relatively small number of samples, compared to the size of the service area.
Pickering responded to Gurewitsch’s concern, and said while PWSA saw a drop in homes sampled for EPA compliance, the agency also has monitors throughout its system to continuously keep tabs on lead levels. In addition, the agency has a few hundred volunteer households that allow it to sample homes with known lead lines on an ongoing basis.
“The additional data has only backed up the initial drop,” PWSA saw last summer, said Pickering. “I think we now have mountains of data to demonstrate that it’s working, and it’s consistent with other water systems.”
While the decrease in lead levels is encouraging, Pickering said the agency must remain aggressive.
“We know that by removing the lead, that’s the ultimate solution to addressing lead in water,” he said, referring to the agency’s plan to remove all lead lines from the system by 2026.
Since 2016 PWSA has replaced over 7,400 public lines and 4,600 private lines. Initially, state law prohibited PWSA from digging up lead service lines that ran from the curb into customers’ homes. But the EPA required PWSA to replace a certain number of lead lines per year, so they were doing partial lead line replacements, in which the public portion of the line—from the water main in the street to the curb—was dug out, but the private side was left intact. Studies have shown that such replacements can actually increase lead levels in the short term.
Working with Mayor Bill Peduto’s administration and state representatives, state law was amended, and PWSA began a program of full lead line replacements.
