Hinsdale
- Monitoring TTHM: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 4 times in July 2024. EPA records do not show all of these as returned to compliance.
IL / Hinsdale
IL · Tap water records
Hinsdale tap water, in plain English
Here is what the EPA's own data shows about tap water in Hinsdale. According to EPA SDWIS data retrieved June 2026, Hinsdale is served by 2 active community water systems, together reported to serve about 18,300 people.
As of June 2026, EPA records show 4 violations across the community water system(s) serving Hinsdale, going back to the earliest EPA record. None were health-based; the records are monitoring or reporting violations (a required test or report was late or missed). Each is listed by system below, with its status.
- 2Community water systems
- ~18,300People served (EPA-reported)
- June 2026EPA records reviewed through
What the EPA has on record, by system
Knolls Water Cooperative
As of June 2026, EPA records show no reported violations for this system in the period covered. This is not a guarantee about every substance, or about the water inside your home's plumbing.
What this means
A health-based violation means a contaminant was recorded above the limit the EPA tracks for it. A monitoring or reporting violation means a required test or report was late or missed — not that a contaminant was measured above a limit. “Returned to compliance” means the EPA recorded the issue as resolved.
This page summarizes the EPA's own records and does not assess whether your water is safe to drink. For the most current details, you can verify every record directly with the EPA, and contact your water system with questions.
Source: U.S. EPA Envirofacts SDWIS, retrieved June 2026. Records cover the EPA's full reporting history for these systems. Verify at EPA ECHO.