Here is what the EPA's own data shows about tap water in Carson. According to EPA SDWIS data retrieved July 2026, Carson is served by 3 active community water systems, together reported to serve about 4,059 people.
As of July 2026, EPA records show 54 violations across the community water system(s) serving Carson, going back to the earliest EPA record. None were health-based; the records are monitoring or reporting violations (a required test or report was late or missed). Each is listed by system below, with its status.
Monitoring Revised Total Coliform Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 5 times between May 2022 and April 2025. 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 3 times between May 2022 and April 2025. 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 2016 and January 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 2 times between January 2016 and January 2017. 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 2 times between July 2013 and July 2014. All have since returned to compliance, per EPA records.
Underwood
1,000 served · groundwater · PWSID WA5390200
Monitoring Revised Total Coliform Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 5 times between May 2022 and April 2025. All have since returned to compliance, per EPA records.
Monitoring Endrin: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2023. EPA records do not show all of these as returned to compliance.
Monitoring BHC-GAMMA: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2023. EPA records do not show all of these as returned to compliance.
Monitoring Methoxychlor: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2023. EPA records do not show all of these as returned to compliance.
Monitoring Toxaphene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2023. EPA records do not show all of these as returned to compliance.
Monitoring Di(2-ethylhexyl) adipate: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2023. EPA records do not show all of these as returned to compliance.
Monitoring Simazine: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2023. EPA records do not show all of these as returned to compliance.
Monitoring Di(2-ethylhexyl) phthalate: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2023. EPA records do not show all of these as returned to compliance.
Monitoring Hexachlorocyclopentadiene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2023. EPA records do not show all of these as returned to compliance.
Monitoring Metolachlor: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2023. EPA records do not show all of these as returned to compliance.
Monitoring Atrazine: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2023. EPA records do not show all of these as returned to compliance.
Monitoring LASSO: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2023. EPA records do not show all of these as returned to compliance.
Monitoring Heptachlor: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2023. EPA records do not show all of these as returned to compliance.
Monitoring Heptachlor epoxide: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2023. EPA records do not show all of these as returned to compliance.
Monitoring Dieldrin: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2023. EPA records do not show all of these as returned to compliance.
Monitoring Butachlor: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2023. EPA records do not show all of these as returned to compliance.
Monitoring Propachlor: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2023. EPA records do not show all of these as returned to compliance.
Monitoring HEXACHLOROBENZENE: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2023. EPA records do not show all of these as returned to compliance.
Monitoring Benzo(a)pyrene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2023. EPA records do not show all of these as returned to compliance.
Monitoring Metribuzin: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2023. EPA records do not show all of these as returned to compliance.
Monitoring Chlordane: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2023. EPA records do not show all of these as returned to compliance.
Monitoring Consumer Confidence Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times between July 2012 and July 2014. All have since returned to compliance, per EPA records.
Wind River Community
44 served · groundwater · PWSID WA5320029
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 2015 and January 2022. 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 2 times between May 2020 and May 2021. 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 between July 2007 and January 2018. 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 4 times between July 2012 and July 2015. 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.