Here is what the EPA's own data shows about tap water in Chester. According to EPA SDWIS data retrieved October 2026, Chester is served by 6 active community water systems, together reported to serve about 1,502 people.
As of October 2026, EPA records show 75 violations across the community water system(s) serving Chester, going back to the earliest EPA record. 21 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 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 Combined Radium (-226 and -228): 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 Gross Alpha, Excl. Radon and U: 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 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 2010. All have since returned to compliance, per EPA records.
Sage Creek Co Water District
225 served · groundwater · PWSID MT0003150
Monitoring Consumer Confidence Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 11 times between July 2003 and October 2025. 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 once in February 2025. 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 3 times between October 2007 and December 2024. All have since returned to compliance, per EPA records.
Monitoring E. COLI: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in September 2011. All have since returned to compliance, per EPA records.
Riverview Colony
130 served · surface water · PWSID MT0001777
Health-based Total Haloacetic Acids (HAA5): a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 12 times between October 2018 and July 2023. The EPA record lists a level of 61.5 UG/L; the limit (MCL) is 60 UG/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 4 times between April 2019 and January 2020. The EPA record lists a level of 88.8 UG/L; the limit (MCL) is 80 UG/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 once in March 2008. The EPA record for these does not include a measured level. 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 once in October 2021. 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 2003. 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 January 1994 and January 1997. All have since returned to compliance, per EPA records.
Sage Creek Colony
130 served · groundwater · PWSID MT0001779
Monitoring Nitrate-Nitrite: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2024. 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 once in September 2018. 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 December 2014. All have since returned to compliance, per EPA records.
Hi-Line Colony
92 served · groundwater · PWSID MT0005185
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 2025. 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 2 times between March 2025 and April 2025. All have since returned to compliance, per EPA records.
Monitoring OXAMYL: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in April 2025. All have since returned to compliance, per EPA records.
Monitoring Simazine: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in April 2025. All have since returned to compliance, per EPA records.
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 April 2025. All have since returned to compliance, per EPA records.
Monitoring Picloram: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in April 2025. All have since returned to compliance, per EPA records.
Monitoring Dinoseb: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in April 2025. All have since returned to compliance, per EPA records.
Monitoring Hexachlorocyclopentadiene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in April 2025. All have since returned to compliance, per EPA records.
Monitoring Carbofuran: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in April 2025. All have since returned to compliance, per EPA records.
Monitoring Atrazine: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in April 2025. All have since returned to compliance, per EPA records.
Monitoring LASSO: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in April 2025. All have since returned to compliance, per EPA records.
Monitoring Heptachlor: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in April 2025. All have since returned to compliance, per EPA records.
Monitoring Heptachlor epoxide: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in April 2025. All have since returned to compliance, per EPA records.
Monitoring 2,4-D: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in April 2025. All have since returned to compliance, per EPA records.
Monitoring 2,4,5-TP: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in April 2025. All have since returned to compliance, per EPA records.
Monitoring HEXACHLOROBENZENE: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in April 2025. All have since returned to compliance, per EPA records.
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 April 2025. All have since returned to compliance, per EPA records.
Monitoring Pentachlorophenol: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in April 2025. All have since returned to compliance, per EPA records.
Monitoring Chlordane: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in 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 April 2025. All have since returned to compliance, per EPA records.
Monitoring BHC-GAMMA: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in April 2025. All have since returned to compliance, per EPA records.
Monitoring Methoxychlor: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in April 2025. All have since returned to compliance, per EPA records.
Monitoring Toxaphene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in April 2025. All have since returned to compliance, per EPA records.
Monitoring Dalapon: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in April 2025. All have since returned to compliance, per EPA records.
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 April 2025. All have since returned to compliance, per EPA records.
South Chester Water Dist
55 served · surface water · PWSID MT0000007
Health-based Total Haloacetic Acids (HAA5): a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 3 times between October 2024 and April 2026. The EPA record lists a level of 0.063 MG/L; the limit (MCL) is 0.06 MG/L. EPA records do not show all of these as returned to compliance.
Health-based Surface Water Treatment Rule: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded once in June 2009. The EPA record for these does not include a measured level. 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 2023. 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 October 2026. Records cover the EPA's full reporting history for these systems. Verify at EPA ECHO.