OK / Fairfax
OK · Tap water records
Fairfax tap water, in plain English
Here is what the EPA's own data shows about tap water in Fairfax. According to EPA SDWIS data retrieved June 2026, Fairfax is served by 2 active community water systems, together reported to serve about 1,655 people.
As of June 2026, EPA records show 680 violations across the community water system(s) serving Fairfax, going back to the earliest EPA record. 484 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
Fairfax
1,555 served · surface water · PWSID OK1021204 - Health-based CARBON, TOTAL: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 70 times between October 2016 and July 2024. 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 TTHM: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 168 times between April 2004 and October 2023. The EPA record lists a level of 0.098 ; the limit (MCL) is 0.08 . EPA records do not show all of these as returned to compliance.
- Health-based Total Haloacetic Acids (HAA5): a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 65 times between April 2007 and January 2022. The EPA record lists a level of 0.07 MG/L; the limit (MCL) is 0.06 MG/L. EPA records do not show all of these as returned to compliance.
- Health-based Interim Enhanced Surface Water Treatment Rule: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 2 times in March 2020. The EPA record for these does not include a measured level. All have since returned to compliance, per EPA records.
- Health-based Coliform (TCR): a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 2 times between August 1991 and August 1994. The EPA record lists a level of 0 ; the limit (MCL) is 0 . All have since returned to compliance, per EPA records.
- Health-based Turbidity: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 3 times between January 1987 and May 1993. The EPA record lists a level of 5.6 ; the limit (MCL) is 5 . All have since returned to compliance, per EPA records.
- Health-based Coliform (Pre-TCR): a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 3 times between June 1980 and July 1987. The EPA record lists a level of 80 ; the limit (MCL) is 0 . All have since returned to compliance, per EPA records.
- Monitoring Sodium: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times in January 2024. EPA records do not show all of these as returned to compliance.
- 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 7 times between July 2020 and October 2022. EPA records do not show all of these as returned to compliance.
- Monitoring Combined Uranium: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 7 times between July 2020 and October 2022. 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 7 times between July 2020 and October 2022. EPA records do not show all of these as returned to compliance.
- Monitoring Gross Beta Particle Activity: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 7 times between July 2020 and October 2022. 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 10 times between January 1994 and July 2022. 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 11 times between December 2015 and April 2022. 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 2 times between July 2020 and October 2021. 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 2 times between July 2020 and October 2021. 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 2 times between July 2020 and October 2021. 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 2 times between July 2020 and October 2021. 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 2 times between July 2020 and October 2021. 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 2 times between July 2020 and October 2021. 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 2 times between July 2020 and October 2021. 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 2 times between July 2020 and October 2021. 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 2 times between July 2020 and October 2021. 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 2 times between July 2020 and October 2021. 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 2 times between July 2020 and October 2021. 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 2 times between July 2020 and October 2021. 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 2 times between July 2020 and October 2021. 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 2 times between July 2020 and October 2021. 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 2 times between July 2020 and October 2021. 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 2 times between July 2020 and October 2021. 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 2 times between July 2020 and October 2021. 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 2 times between July 2020 and October 2021. 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 2 times between July 2020 and October 2021. 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 2 times between July 2020 and October 2021. 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 2 times between July 2020 and October 2021. 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 7 times between April 2017 and June 2021. 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 2 times between January 2017 and January 2021. 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 January 2020. All have since returned to compliance, per EPA records.
- Monitoring Chlorine: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 4 times between July 2015 and October 2019. 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 2 times between July 1994 and August 1997. 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 6 times between October 1979 and February 1990. 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 3 times between April 1985 and June 1985. All have since returned to compliance, per EPA records.
Grayhorse Rwd
100 served · surface water · PWSID OK3005717 - Health-based TTHM: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 97 times between January 2016 and October 2025. The EPA record lists a level of 0.162 MG/L; the limit (MCL) is 0.08 MG/L. EPA records do not show all of these as returned to compliance.
- Health-based Total Haloacetic Acids (HAA5): a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 70 times between October 2017 and October 2025. The EPA record lists a level of 0.068 MG/L; the limit (MCL) is 0.06 MG/L. EPA records do not show all of these as returned to compliance.
- Health-based Coliform (TCR): a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded once in August 1991. The EPA record lists a level of 0 ; the limit (MCL) is 0 . All have since returned to compliance, per EPA records.
- Health-based Coliform (Pre-TCR): a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 3 times between October 1982 and September 1986. The EPA record lists a level of 12 ; the limit (MCL) is 1 . 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 22 times between March 2016 and September 2025. EPA records do not show all of these as returned to compliance.
- Monitoring Total Haloacetic Acids (HAA5): a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 18 times between April 2018 and September 2025. 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 7 times between July 2012 and July 2024. 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 June 1993 and October 2021. 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 4 times between June 1991 and August 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 21 times between October 1979 and November 1990. 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.