CA / Arroyo Grande
CA · Tap water records
Arroyo Grande tap water, in plain English
Here is what the EPA's own data shows about tap water in Arroyo Grande. According to EPA SDWIS data retrieved June 2026, Arroyo Grande is served by 13 active community water systems, together reported to serve about 23,709 people.
As of June 2026, EPA records show 157 violations across the community water system(s) serving Arroyo Grande, going back to the earliest EPA record. 107 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
City Of Arroyo Grande Utilities Division
17,963 served · surface water · PWSID CA4010001 - 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 May 2025. EPA records do not show all of these as returned to compliance.
Woodlands Development
3,862 served · surface water · PWSID CA4010081 - 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 June 2008. All have since returned to compliance, per EPA records.
Mesa Dunes Mobile Home Estates
600 served · groundwater · PWSID CA4000650 - 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 February 2021. 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 2 times between January 2018 and January 2019. 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 2 times between January 2018 and January 2019. All have since returned to compliance, per EPA records.
Woodland Park Mutual Water Co
538 served · groundwater · PWSID CA4000506 - Health-based Nitrate: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 29 times between April 2023 and October 2025. The EPA record lists a level of 11 MG/L; the limit (MCL) is 10 MG/L. 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 12 times between October 2018 and October 2023. All have since returned to compliance, per EPA records.
Canyon Crest Mutual Benefit Wc
133 served · surface water · PWSID CA4000230 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.
Edna Valley Ranch East
132 served · groundwater · PWSID CA4000202 - Monitoring Nitrate: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times between January 2017 and January 2020. 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 4 times between January 2018 and July 2019. All have since returned to compliance, per EPA records.
Varian Ranch Mutual Water
105 served · groundwater · PWSID CA4000765 - 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.
Ken Mar Gardens
84 served · groundwater · PWSID CA4000648 - Health-based Selenium: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 33 times between October 2020 and October 2025. 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 Nitrate: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 3 times in January 2024. The EPA record lists a level of 16 MG/L; the limit (MCL) is 10 MG/L. 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 3 times in January 2023. 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 3 times in October 2021. All have since returned to compliance, per EPA records.
Laguna Negra Mutual Water Co.
80 served · groundwater · PWSID CA4000705 - Monitoring Nitrate: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 4 times between January 2017 and January 2023. 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 5 times between October 2017 and October 2021. All have since returned to compliance, per EPA records.
H2o, Inc
70 served · groundwater · PWSID CA4000741 - 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 October 2020 and October 2024. EPA records do not show all of these as returned to compliance.
Country Hills Estates
60 served · groundwater · PWSID CA4000637 - Health-based Arsenic: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 42 times between July 2007 and April 2019. The EPA record lists a level of 0.023 MG/L; the limit (MCL) is 0.01 MG/L. 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 2 times in January 2019. 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 July 2005. All have since returned to compliance, per EPA records.
Rancho Nipomo Water Company
44 served · groundwater · PWSID CA4000771 - 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 2005. 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 July 1993. All have since returned to compliance, per EPA records.
Terra De Oro Water Company
38 served · groundwater · PWSID CA4000749 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.
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.