OK / Marshall
OK · Tap water records
Marshall tap water, in plain English
Here is what the EPA's own data shows about tap water in Marshall. According to EPA SDWIS data retrieved June 2026, Marshall is served by 2 active community water systems, together reported to serve about 1,876 people.
As of June 2026, EPA records show 33 violations across the community water system(s) serving Marshall, going back to the earliest EPA record. 4 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
Logan Co Rws & Swmd #3
1,618 served · groundwater · PWSID OK2004230 - Health-based LEAD AND COPPER RULE REVISIONS: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded once in October 2024. The EPA record for these does not include a measured level. All have since returned to compliance, per EPA records.
- Health-based Nitrate-Nitrite: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 2 times in July 2021. The EPA record lists a level of 11 MG/L; the limit (MCL) is 10 MG/L. All have since returned to compliance, per EPA records.
- Monitoring LEAD AND COPPER RULE REVISIONS: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in October 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 May 2014. 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 3 times between July 1992 and December 1995. 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 January 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 March 1983 and September 1990. All have since returned to compliance, per EPA records.
Marshall
258 served · groundwater · PWSID OK3004201 - Health-based Coliform (Pre-TCR): a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded once in July 1983. The EPA record lists a level of 24 ; the limit (MCL) is 1 . 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 9 times between July 2006 and July 2025. 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 11 times between December 1981 and July 1983. 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.