CA / Riverdale
CA · Tap water records
Riverdale tap water, in plain English
Here is what the EPA's own data shows about tap water in Riverdale. According to EPA SDWIS data retrieved June 2026, Riverdale is served by 2 active community water systems, together reported to serve about 2,836 people.
As of June 2026, EPA records show 128 violations across the community water system(s) serving Riverdale, going back to the earliest EPA record. 120 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.
What the EPA has on record, by system
Riverdale Public Utility District
2,756 served · groundwater · PWSID CA1010028 - Health-based Fluoride: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 2 times in January 2025. The EPA record lists a level of 2.48 MG/L; the limit (MCL) is 2 MG/L. EPA records do not show all of these as returned to compliance.
- Health-based Arsenic: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 90 times between April 2006 and April 2014. The EPA record lists a level of 0.047 MG/L; the limit (MCL) is 0.01 MG/L. All have since returned to compliance, per EPA records.
- Health-based Coliform (TCR): a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 12 times between August 1992 and September 2013. The EPA record for these does not include a measured level. All have since returned to compliance, per EPA records.
- Monitoring Nitrate: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times in January 2016. 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 5 times between January 1998 and October 2013. All have since returned to compliance, per EPA records.
Terra Linda Farms
80 served · surface water · PWSID CA1009222 - Health-based Total Haloacetic Acids (HAA5): a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 8 times between January 2017 and October 2017. The EPA record lists a level of 0.091 MG/L; the limit (MCL) is 0.06 MG/L. All have since returned to compliance, per EPA records.
- Health-based TTHM: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 6 times between October 2014 and April 2017. The EPA record lists a level of 0.09 MG/L; the limit (MCL) is 0.08 MG/L. All have since returned to compliance, per EPA records.
- Health-based Surface Water Treatment Rule: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 2 times in March 2012. The EPA record for these does not include a measured level. 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 June 2026. Records cover the EPA's full reporting history for these systems. Verify at EPA ECHO.