Here is what the EPA's own data shows about tap water in Delafield. According to EPA SDWIS data retrieved July 2026, Delafield is served by 9 active community water systems, together reported to serve about 1,517 people.
As of July 2026, EPA records show 72 violations across the community water system(s) serving Delafield, going back to the earliest EPA record. 8 of these are classified by the EPA as health-based (a contaminant recorded above the limit the EPA tracks); the rest are monitoring or reporting violations. Each is listed by system below, with its status.
Monitoring Lead and Copper Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times between January 2013 and January 2025. All have since returned to compliance, per EPA records.
Monitoring Consumer Confidence Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in October 2003. All have since returned to compliance, per EPA records.
St Johns Northwestern Academies
340 served · groundwater · PWSID WI2680761
Health-based LEAD AND COPPER RULE REVISIONS: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded once in October 2024. The EPA record for these does not include a measured level. All have since returned to compliance, per EPA records.
Health-based Stage 1 Disinfectants and Disinfection Byproducts Rule: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 2 times in December 2021. The EPA record for these does not include a measured level. All have since returned to compliance, per EPA records.
Monitoring Public Notice: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times between September 2003 and October 2024. EPA records do not show all of these as returned to compliance.
Monitoring LEAD AND COPPER RULE REVISIONS: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in October 2024. All have since returned to compliance, per EPA records.
Monitoring Chlorine: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 6 times between January 2017 and April 2022. All have since returned to compliance, per EPA records.
Monitoring Revised Total Coliform Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 8 times between November 2021 and March 2022. EPA records do not show all of these as returned to compliance.
Monitoring Lead and Copper Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 4 times between January 2013 and January 2022. All have since returned to compliance, per EPA records.
Monitoring Consumer Confidence Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 7 times between July 2009 and July 2015. All have since returned to compliance, per EPA records.
Delafield Waterworks
300 served · groundwater · PWSID WI2684642
Monitoring Consumer Confidence Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in July 2001. All have since returned to compliance, per EPA records.
Monitoring Lead and Copper Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 1995. All have since returned to compliance, per EPA records.
Arbors
280 served · groundwater · PWSID WI2682795
Health-based LEAD AND COPPER RULE REVISIONS: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 2 times in October 2024. The EPA record for these does not include a measured level. All have since returned to compliance, per EPA records.
Monitoring LEAD AND COPPER RULE REVISIONS: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in October 2024. All have since returned to compliance, per EPA records.
Monitoring Public Notice: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in October 2024. EPA records do not show all of these as returned to compliance.
Monitoring Consumer Confidence Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 7 times between July 2009 and July 2017. All have since returned to compliance, per EPA records.
Monitoring Lead and Copper Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2013. All have since returned to compliance, per EPA records.
Country Aire Apartments 2
90 served · groundwater · PWSID WI2680247
Monitoring Lead and Copper Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 1995. All have since returned to compliance, per EPA records.
Country Aire Apartments 3
80 served · groundwater · PWSID WI2680249
Monitoring Lead and Copper Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 1995. All have since returned to compliance, per EPA records.
Sanctuary Of Delafield
27 served · groundwater · PWSID WI2685951
Health-based Revised Total Coliform Rule: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 3 times in June 2024. The EPA record for these does not include a measured level. EPA records do not show all of these as returned to compliance.
Monitoring Consumer Confidence Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 5 times in July 2023. All have since returned to compliance, per EPA records.
Wells St Station 425 West
25 served · groundwater · PWSID WI2686466
Monitoring Consumer Confidence Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times in July 2023. All have since returned to compliance, per EPA records.
Monitoring Total Haloacetic Acids (HAA5): a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2017. All have since returned to compliance, per EPA records.
Monitoring TTHM: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2017. All have since returned to compliance, per EPA records.
Monitoring Lead and Copper Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in April 2016. All have since returned to compliance, per EPA records.
Wells St Station 435 East
25 served · groundwater · PWSID WI2686619
Monitoring Consumer Confidence Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times in July 2023. All have since returned to compliance, per EPA records.
Monitoring TTHM: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2017. All have since returned to compliance, per EPA records.
Monitoring Total Haloacetic Acids (HAA5): a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2017. All have since returned to compliance, per EPA records.
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 July 2026. Records cover the EPA's full reporting history for these systems. Verify at EPA ECHO.