Cucamonga Valley Water District
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.
CA / Rancho Cucamonga
CA · Tap water records
Rancho Cucamonga tap water, in plain English
Here is what the EPA's own data shows about tap water in Rancho Cucamonga. According to EPA SDWIS data retrieved June 2026, Rancho Cucamonga is served by 4 active community water systems, together reported to serve about 211,996 people.
As of June 2026, EPA records show 16 violations across the community water system(s) serving Rancho Cucamonga, going back to the earliest EPA record. 1 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.
- 4Community water systems
- ~211,996People served (EPA-reported)
- June 2026EPA records reviewed through
What the EPA has on record, by system
Laguna Mobile Home And Rv Park
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.
Californian Mobile Home Park
- Health-based Heterotrophic Bacteria (HPC or SPC): a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded once in September 2019. 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 5 times between July 2017 and October 2021. All have since returned to compliance, per EPA records.
- Monitoring COPPER, FREE: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2019. EPA records do not show all of these as returned to compliance.
- Monitoring Lead: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2019. EPA records do not show all of these as returned to compliance.
- Monitoring Nitrate: 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 Revised Total Coliform Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times between July 2016 and November 2016. All have since returned to compliance, per EPA records.
Mono Vista Ranch Mhp
- 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 April 2024. 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 2 times in January 2024. 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.