Aurora issues public notice after new testing finds 90th-percentile lead level above federal action level

Aurora officials told the City Council’s Committee of the Whole on July 15 that new 2025 lead‑in‑drinking‑water testing produced results that triggered a required public notice and changes to the city’s replacement timeline. Jason Bauer, director of public works, said the city completed 100 fifth‑liter samples from January through June and that the 90th‑percentile result was 20.6 parts per billion, above the 15 ppb action level used to determine compliance.

The city issued a public notice through news outlets after exceeding the action level, Bauer said, and is expanding work it said it already had underway: replacing lead service lines and conducting a corrosion‑control study. “The water in the plant is lead free,” Bauer said. “Where lead gets into the system is in the service lines. Replacing the lead service lines is the only thing that’s within the purview of the water utility.”

Why it matters: the federal action level — 15 ppb — is the compliance threshold that, when exceeded at the 90th percentile of required samples, triggers required public notification and additional corrective steps by a water utility.

What the city reported: Bauer said Aurora has been doing partial replacements and voluntary replacements for years and has replaced roughly 2,500 lead service lines since 2018 at no cost to residents when those lines were disturbed by city projects. He said the city’s inventory of service lines is changing as replacements continue and estimated that by the end of this year the remaining suspected lead service lines would be reduced below 16,000.

Bauer described several operational changes tied to 2025 testing standards: early‑year reduced monitoring shifted to standard monitoring; sampling moved from the first liter to the fifth liter (which reflects water that has sat in a service line for at least six hours); and a new requirement to sample 20% of schools and day‑care facilities. He said the city expected some test results to rise because the fifth‑liter sample more directly measures water that has been in contact with service lines for a long period.

City actions and near‑term work: the public works director said Aurora will (1) continue and expand lead service line replacements, (2) proceed with a corrosion‑control dosing study using harvested lead pipe racks at the treatment plant (IEPA requested the study and results are expected next year), (3) publish public‑education materials through the IEPA review process, and (4) maintain an interactive lead‑service‑line map on the city website that is updated daily.

Bauer said the city ran 100 samples and that 81 of those samples were under laboratory detection limits or otherwise below concern thresholds, while 19 exceeded the action level and were placed into the replacement program. He said some adjacent homes with the same type of service line had markedly different results and that staff had not identified a single pattern to explain the variation.

Costs and resident guidance: Bauer told aldermen that independent lead testing for a homeowner typically costs about $40–$50 and that the city can provide laboratories’ names but does not perform household tests in‑house. He also said the city provides a “lead pitcher” and roughly six months of replacement filters when the city replaces a customer’s service line as part of a capital project; he estimated retail cost for such a pitcher plus 6 months of filters at roughly $25–$50. Bauer said the city is not mandated to begin full replacement until 2027 under state timelines but that because Aurora exceeded the action level it will start mandated replacements in 2026 and has budgeted accordingly.

Council oversight and communications: multiple aldermen asked for consistent resident messaging and for the city to provide a cut‑and‑paste statement the aldermen could share with constituents. Bauer said his department and communications staff are preparing a FAQ and a brief statement for distribution and that specific staff email inboxes will be monitored so reported elevated results are routed promptly to engineering for follow up.

What the city did not say or could not confirm: staff made a number of numeric estimates during discussion (for example, the current inventory counts and the exact annual replacement pace next year). Where the transcript recorded different figures (Bauer referenced being “up close to 19,000” and then “under 16,000 by the end of this year”), the city presentation was the source for those numbers and the department indicated inventories update daily on the replacement map. Bauer also said the corrosion‑control dosing is inexpensive to implement if proved effective.

Ending: Bauer closed by urging constituents with concerns to use the website interactive map and the city’s contact channels to request a site visit or confirm material at the meter. Council members asked staff to circulate the final FAQ and the standardized statement to aldermen before wide distribution.