Public water system · LA2095008
ActiveMarathon Petroleum Company LLC
At a glance
Marathon Petroleum Company LLC (PWSID LA2095008) is an active non-transient non-community water system in St. John the Baptist Parish County, Louisiana. It reports serving 817 people through 1 service connection. Its primary water source is surface water, and EPA lists it as privately owned. Of the 12 most recent violations in EPA's records, 9 are health-based, and the most recent began in October 2024.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
817
Service connections
1
Primary source
SW
Surface water
System type
NTNCWS
Non-transient non-community water system
System record
How does Marathon Petroleum Company LLC compare with other water systems in St. John the Baptist Parish County?
By EPA's size categories, Marathon Petroleum Company LLC is a small system (501 to 3,300 people). St. John the Baptist Parish County has 12 active public water systems, and Marathon Petroleum Company LLC is the 4th-largest of them by population served. Its population served is well below the county average of 3,983 people per system, and accounts for 1.7% of the 47,793 people reported by systems filed under the county. Across Louisiana, the 1,121 active systems average 4,685 people each. Nationally, the average active non-transient non-community water system reports serving 430 people, so Marathon Petroleum Company LLC is about twice that figure.
What does “non-transient non-community water system” mean?
A non-transient non-community water system regularly serves at least 25 of the same people for more than six months a year, but not where they live. Schools, factories, office buildings and hospitals with their own supply are typical examples. Louisiana has 125 active non-transient non-community water systems, 11% of the state's 1,121 active systems. Surface water means the system draws its water from rivers, lakes, streams or reservoirs. 53 Louisiana systems (4.7%) list surface water as their primary source.
Who owns and regulates Marathon Petroleum Company LLC?
EPA lists Marathon Petroleum Company LLC as privately owned. The LA state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 8 of the 12 active systems in St. John the Baptist Parish County (67%) are also privately owned.
Does Marathon Petroleum Company LLC have drinking water violations?
Of the 12 most recent violations in EPA's records, 9 are health-based, and the most recent began in October 2024. The violations listed here began between March 2007 and October 2024. By type: 8 contaminant level above the legal limit, 2 monitoring and reporting, 1 monitoring and 1 required treatment not met. The contaminant or rule involved most often is Total trihalomethanes (TTHM) (8 of them). EPA lists 10 as resolved and 2 as archived. Resolved means at least one resolving action is on record: the system returned to compliance, the rule no longer applies, or no further action was needed. Archived means the violation was not marked resolved but is more than five years past the end of the noncompliance period, so it no longer counts toward current compliance status.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2024-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | Archived |
| 2024-08-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Resolved |
| 2024-08-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2024-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | Archived |
| 2015-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | Resolved |
| 2015-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | Resolved |
| 2015-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | Resolved |
| 2014-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | Resolved |
| 2014-07-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2014-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | Resolved |
| 2014-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | Resolved |
| 2007-03-01 | Required treatment not metTreatment Technique (SWTR and GWR) · code 41 | Surface Water Treatment Rulecode 0200 | Yes | Resolved |
The 12 most recent violations in EPA's records, newest first.Labels and codes come from EPA's SDWIS reference tables. A monitoring or reporting violation means a required test or report was missed or late; it does not by itself mean a contaminant was found. "Health-based" marks violations of a legal limit or required treatment.
Marathon Petroleum Company LLC: frequently asked questions
Who runs Marathon Petroleum Company LLC?
Marathon Petroleum Company LLC (PWSID LA2095008) is a non-transient non-community water system privately owned. It is regulated by the LA state drinking water program.
How many people does Marathon Petroleum Company LLC serve?
Marathon Petroleum Company LLC reports serving 817 people through 1 service connection in St. John the Baptist Parish County, Louisiana.
Where does Marathon Petroleum Company LLC get its water?
EPA SDWIS lists this system's primary water source as surface water. Surface water means the system draws its water from rivers, lakes, streams or reservoirs.
Does Marathon Petroleum Company LLC have any drinking water violations?
Of the 12 most recent violations in EPA's records, 9 are health-based, and the most recent began in October 2024. A monitoring or reporting violation means a required test or report was missed or late; it does not by itself mean a contaminant was found.
Is Marathon Petroleum Company LLC's water safe to drink?
AquaCensus shows EPA compliance records, not current water test results, so it cannot say whether the water is safe at a given moment. Of the 12 most recent violations in EPA's records, 9 are health-based, and the most recent began in October 2024. For current results, consult EPA ECHO, or the LA state drinking water program.
Where can I find Marathon Petroleum Company LLC's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Marathon Petroleum Company LLC is a non-transient non-community water system, so it is not required to publish one; like every public water system, it must notify the people it serves about violations under EPA's public notification rules.
Other water systems in St. John the Baptist Parish County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| St John Water District 3 | St. John the Baptist Parish | 31,965 | Community | Groundwater |
| St John Water District 1 | St. John the Baptist Parish | 10,484 | Community | Surface water |
| St John Water District 2 | St. John the Baptist Parish | 3,702 | Community | Surface water |
| Pleasure Bend Water Supply | St. John the Baptist Parish | 528 | Community | Groundwater |
| Pinnacle Polymers | St. John the Baptist Parish | 110 | Non-transient non-community | Groundwater |
| Frenier Landing Restaurant | St. John the Baptist Parish | 50 | Transient non-community | Groundwater |
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About this data
Source: U.S. EPA Safe Drinking Water Information System (SDWIS) and SDWA violation records, via EPA ECHO, as published October 1, 2026 — AquaCensus refreshes it quarterly. See the methodology for how records are matched, cleaned and scored.
Cite as: AquaCensus, “Marathon Petroleum Company LLC, PWSID LA2095008, Louisiana”, https://aquacensus.com/water-systems/louisiana/marathon-petroleum-company-llc-la2095008 (data as of October 1, 2026).