Here is what the EPA's own data shows about tap water in Idaho City. According to EPA SDWIS data retrieved October 2026, Idaho City is served by 2 active community water systems, together reported to serve about 694 people.
As of October 2026, EPA records show 45 violations across the community water system(s) serving Idaho City, going back to the earliest EPA record. 10 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.
Health-based Interim Enhanced Surface Water Treatment Rule: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 9 times between March 2017 and April 2023. The EPA record for these does not include a measured level. All have since returned to compliance, per EPA records.
Health-based Groundwater Rule: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded once in March 2019. The EPA record for these does not include a measured level. All have since returned to compliance, per EPA records.
Monitoring CYANIDE: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2022. All have since returned to compliance, per EPA records.
Monitoring Radium-226: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2020. EPA records do not show all of these as returned to compliance.
Monitoring Radium-228: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2020. EPA records do not show all of these as returned to compliance.
Monitoring Interim Enhanced Surface Water Treatment Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 7 times between July 2016 and July 2019. All have since returned to compliance, per EPA records.
Monitoring E. COLI: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times between October 2017 and June 2018. 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 3 times between December 2011 and December 2017. EPA records do not show all of these as returned to compliance.
Monitoring Chlorine: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 5 times between October 2016 and October 2017. 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 between September 2014 and September 2017. All have since returned to compliance, per EPA records.
Monitoring Surface Water Treatment Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 9 times between July 2016 and September 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 April 2017. All have since returned to compliance, per EPA records.
Monitoring Endothall: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2017. EPA records do not show all of these as returned to compliance.
Monitoring Revised Total Coliform Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in November 2016. All have since returned to compliance, per EPA records.
Duquette Pines Homeowners Association
163 served · groundwater · PWSID ID4080016
Monitoring E. COLI: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in April 2019. EPA records do not show all of these as returned to compliance.
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 October 2026. Records cover the EPA's full reporting history for these systems. Verify at EPA ECHO.