Here is what the EPA's own data shows about tap water in Cottonwood. According to EPA SDWIS data retrieved July 2026, Cottonwood is served by 4 active community water systems, together reported to serve about 7,150 people.
As of July 2026, EPA records show 11 violations across the community water system(s) serving Cottonwood, going back to the earliest EPA record. 4 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 Coliform (TCR): a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2004. All have since returned to compliance, per EPA records.
Cottonwood Water District
3,316 served · groundwater · PWSID CA4510007
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 Revised Total Coliform Rule: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded once in August 2018. 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: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in October 2025. 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.
White Oak Mutual Water Company
415 served · groundwater · PWSID CA4500204
Monitoring Revised Total Coliform Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in June 2022. All have since returned to compliance, per EPA records.
Saddleback Mutual Water Co.
90 served · groundwater · PWSID CA5200645
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. EPA records do not show all of these as returned to compliance.
Health-based Coliform (TCR): a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded once in March 2013. 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 once in October 2024. 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 once in July 1993. 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.