OK / Chelsea
OK · Tap water records
Chelsea tap water, in plain English
Here is what the EPA's own data shows about tap water in Chelsea. According to EPA SDWIS data retrieved June 2026, Chelsea is served by 1 active community water system, together reported to serve about 1,964 people.
As of June 2026, EPA records show 39 violations across the community water system(s) serving Chelsea, going back to the earliest EPA record. 2 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
Chelsea Economic Dev. Auth.
1,964 served · surface water · PWSID OK1021504 - Health-based Surface Water Treatment Rule: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 2 times between November 1998 and February 1999. The EPA record lists a level of 0 ; the limit (MCL) is 0 . All have since returned to compliance, per EPA records.
- Monitoring Interim Enhanced Surface Water Treatment Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in February 2019. All have since returned to compliance, per EPA records.
- 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 2016. All have since returned to compliance, per EPA records.
- Monitoring 1,2,4-Trichlorobenzene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2014. All have since returned to compliance, per EPA records.
- Monitoring cis-1,2-Dichloroethylene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Xylenes, Total: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2014. All have since returned to compliance, per EPA records.
- Monitoring DICHLOROMETHANE: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2014. All have since returned to compliance, per EPA records.
- Monitoring o-Dichlorobenzene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2014. All have since returned to compliance, per EPA records.
- Monitoring p-Dichlorobenzene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Vinyl chloride: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2014. All have since returned to compliance, per EPA records.
- Monitoring 1,1-Dichloroethylene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2014. All have since returned to compliance, per EPA records.
- Monitoring trans-1,2-Dichloroethylene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2014. All have since returned to compliance, per EPA records.
- Monitoring 1,2-Dichloroethane: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2014. All have since returned to compliance, per EPA records.
- Monitoring 1,1,1-Trichloroethane: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Carbon tetrachloride: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2014. All have since returned to compliance, per EPA records.
- Monitoring 1,2-Dichloropropane: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Trichloroethylene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2014. All have since returned to compliance, per EPA records.
- Monitoring 1,1,2-Trichloroethane: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Tetrachloroethylene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2014. All have since returned to compliance, per EPA records.
- Monitoring CHLOROBENZENE: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Benzene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Toluene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Ethylbenzene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2014. All have since returned to compliance, per EPA records.
- Monitoring Styrene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2014. 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 2013. 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 October 2012 and January 2013. All have since returned to compliance, per EPA records.
- Monitoring Coliform (TCR): a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in February 1994. All have since returned to compliance, per EPA records.
- Monitoring Coliform (Pre-TCR): a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times between November 1979 and July 1988. All have since returned to compliance, per EPA records.
- Monitoring Turbidity: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 7 times between December 1986 and May 1988. 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.