States ›Louisiana ›St. Landry Parish ›Grand Coteau

Grand Coteau, LA Tap Water Quality 2026

Water quality report for Grand Coteau, LA — PFAS, lead and copper results, violation history and state inspection findings from EPA SDWIS.

A look at Grand Coteau's drinking water using EPA enforcement records: violations, lead and copper results, PFAS sampling and state inspection findings.

Main Utility: Town Of Grand Coteau Water System PWSID: LA1097001 Updated: 2026 Q2
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1 violation currently open

Lead is 7.00 ppb, 47% of the action level. PFAS has never been sampled at this system.

F

Grand Coteau earns an F for water quality

Graded on violations and lead, with state inspection findings. PFAS not tested.

Lead: 7.00 ppb — 47% of the federal action level
PFAS never sampled at this system
27 violations since 2015, 14 health-based
1 violation currently open
Grand Coteau's lead level vs. all Louisiana community water systems
0 ppb5 ppb10 ppb15 ppb
Lead level: 7.00 ppb — 47% of the federal action level
✓ Lower lead than 5% of Louisiana utilities
Population Served
621
~550 connections
Water Source
Groundwater
Drawn from wells — SDWIS source code GW
Active Violations
1
1 open of 27 since 2015

Lead & Copper Testing

Lead (Pb)
90th percentile of tap samples collected across the distribution system
47% of EPA action level
7.00 ppb
Action level: 15 ppb
Copper (Cu)
90th percentile of tap samples. SDWIS reports a copper figure only when a system exceeds the action level, so any value here is an exceedance.
153.8% of EPA action level
2,000 ppb
Action level: 1,300 ppb
The 90th-percentile lead result is 7.00 ppb, 47% of the 15 ppb federal action level. The action level is a treatment trigger, not a legal maximum, and it is measured across sampled taps rather than at any single home. Copper reached the action level here; a copper figure appears in SDWIS only when a system triggers it.

Contaminant Violations (2015–Present)

ContaminantTypeMeasuredLimitPeriodStatus
Groundwater Rule TREATMENT TECHNIQUE — — 2025 Resolved
Lead and Copper Rule MONITORING AND REPORTING — TT 2025 Resolved
LEAD AND COPPER RULE REVISIONS REPORTING FAILURE — — 2024 Unaddressed
LEAD AND COPPER RULE REVISIONS TREATMENT TECHNIQUE — — 2024 Unaddressed
Lead and Copper Rule MONITORING AND REPORTING — TT 2024 Resolved
Consumer Confidence Rule OTHER — — 2023 Resolved
Public Notice OTHER — — 2022 Resolved
Groundwater Rule TREATMENT TECHNIQUE — — 2022 Resolved
Groundwater Rule TREATMENT TECHNIQUE — — 2022 Resolved
Groundwater Rule TREATMENT TECHNIQUE — — 2022 Resolved
Groundwater Rule TREATMENT TECHNIQUE — — 2022 Resolved
Groundwater Rule TREATMENT TECHNIQUE — — 2022 Resolved
Groundwater Rule TREATMENT TECHNIQUE — — 2022 Resolved
Groundwater Rule TREATMENT TECHNIQUE — — 2022 Resolved
Groundwater Rule TREATMENT TECHNIQUE — — 2022 Resolved
Consumer Confidence Rule OTHER — — 2021 Resolved
Lead and Copper Rule MONITORING AND REPORTING — TT 2021 Resolved
Public Notice OTHER — — 2020 Resolved
Groundwater Rule TREATMENT TECHNIQUE — — 2020 Resolved
Groundwater Rule TREATMENT TECHNIQUE — — 2020 Resolved
Groundwater Rule TREATMENT TECHNIQUE — — 2018 Resolved
Groundwater Rule TREATMENT TECHNIQUE — — 2018 Resolved
Lead and Copper Rule MONITORING AND REPORTING — TT 2018 Resolved
Consumer Confidence Rule OTHER — — 2017 Resolved
Consumer Confidence Rule OTHER — — 2016 Resolved
Consumer Confidence Rule OTHER — — 2016 Resolved
Lead and Copper Rule MONITORING AND REPORTING — TT 2015 Resolved
Understanding violation types MCL violations mean a contaminant exceeded the federal maximum limit — the most serious type.
TT (Treatment Technique) violations mean required treatment procedures weren't followed, but don't necessarily mean contamination occurred.

Violation History

1 violation remains open, out of 27 recorded since 2015 (14 health-based).

About the Main Water System

Utility Town Of Grand Coteau Water System
PWSID LA1097001
Water source Groundwater — Drawn from wells — SDWIS source code GW
Population served 621
Service connections 550
Systems serving this area 2
Regulator State primacy agency
Data through 2026 Q2 — EPA SDWIS

Frequently Asked Questions

Is Grand Coteau tap water safe to drink? ▼
No federal limit is exceeded on record. 1 violation(s) remain open. Lead is 7.00 ppb, 47% of the action level.
Does Grand Coteau water have PFAS? ▼
This system has never been sampled for PFAS. EPA's national monitoring covered systems serving 3,300 people or more, so no results exist — which is not evidence that none is present.
Who supplies water to Grand Coteau? ▼
Town Of Grand Coteau Water System (PWSID LA1097001), one of 2 systems serving this area. Groundwater. Drawn from wells — SDWIS source code GW
When was this system last inspected? ▼
It was last inspected on 2024-11-21. No significant deficiencies were recorded.

What Should Grand Coteau Residents Do?

1
Consider a filter certified for lead
Look for NSF/ANSI 53 certification for lead reduction.
2
Check for a lead service line
Lead reaches tap water mainly through service lines and household plumbing. Suppliers now publish an inventory identifying lead lines.
3
Follow the open violation
This system has an unresolved violation. Contact the supplier for its corrective-action schedule.

Nearby Cities in Louisiana

Opelousas, La Tap Water Quality 2026 St. Landry Parish Eunice, La Tap Water Quality 2026 St. Landry Parish Sunset, La Tap Water Quality 2026 St. Landry Parish Lawtell, La Tap Water Quality 2026 St. Landry Parish Krotz Springs, La Tap Water Quality 2026 St. Landry Parish Port Barre, La Tap Water Quality 2026 St. Landry Parish