Public Water System

WATER & SEWER COMMISSION 4 OF ST MARY

PWSID LA1101011 · Louisiana · 9,709 people served

Failing

WATER & SEWER COMMISSION 4 OF ST MARY is an EPA-regulated public water system in Louisiana (PWSID LA1101011). It serves an estimated 9,709 residents — a small town of customers — across 1 community across 1 ZIP code.

Over the past five years, WATER & SEWER COMMISSION 4 OF ST MARY has recorded 20 EPA health-based violations. The grade of F summarizes this compliance pattern. Specific contaminants, dates, and rule citations are listed in the violation history below.

Service Area

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Centered on the averaged ZIP-code centroid of 1 ZIP served.

Population

9,709

Cities

ZIPs

Violations

EPA Health-Based Violations

Health-based Maximum Contaminant Level (MCL) violations on file for WATER & SEWER COMMISSION 4 OF ST MARY over the past five years of EPA SDWIS reporting.

Haloacetic Acids (HAA5)disinfectant

EPA Code 2456 · Maximum Contaminant Level Exceedance

violations

EPA Limit

0.06 mg/L

Last Reading

.071 MG/L

First Reported

Jul 2024

Most Recent

Jan 2025

What this violation means

Haloacetic Acids (HAA5) are the second major group of disinfection byproducts after TTHMs. They form by the same mechanism — chlorine reacting with organic matter — and pose similar long-term cancer risks. Utilities are required to test quarterly at distribution-system locations to track HAA5 levels.

Recommended precautions

→Activated carbon filtration removes most HAA5.
→Reverse osmosis is highly effective.
→Unlike TTHMs, HAA5 do not significantly off-gas. Use treatment rather than aeration.
→Long-term ingestion is the primary concern, not short-term skin contact.

Read the complete guide to Haloacetic Acids (HAA5)

Total Trihalomethanes (TTHMs)disinfectant

EPA Code 2950 · Maximum Contaminant Level Exceedance

violations

EPA Limit

0.08 mg/L

Last Reading

.081 MG/L

First Reported

Oct 2023

Most Recent

Jul 2024

What this violation means

Total Trihalomethanes (TTHMs) form when chlorine reacts with naturally occurring organic matter — leaves, soil, algae — in source water. They are among the most commonly reported violations because utilities pulling from surface water (rivers, lakes, reservoirs) struggle to balance disinfection with byproduct formation. Long-term exposure has been linked to bladder cancer and adverse pregnancy outcomes.

Recommended precautions

→Activated carbon filters (pitcher, faucet, or under-sink) effectively reduce TTHMs.
→Letting water sit uncovered allows TTHMs to off-gas — leave a pitcher in the fridge for several hours.
→Shower with the bathroom fan on; TTHMs can volatilize into the air during hot showers.
→Boiling reduces TTHMs through volatilization, but only after extended boiling.

Read the complete guide to Total Trihalomethanes (TTHMs)

Source: EPA Safe Drinking Water Information System (SDWIS). Health-based violations only. Older violations may have been resolved; check your utility's most recent Consumer Confidence Report for current status.

Cities Served by WATER & SEWER COMMISSION 4 OF ST MARY

CHARENTON

ZIP Codes Served

70523

About this system

EPA records this system as PWSID LA1101011. Data reflects the most recent EPA SDWIS publication as of 2026-05-18. Public Water System Identifiers (PWSIDs) are assigned by the EPA's Safe Drinking Water Act program to track every regulated water utility in the United States. The first two letters typically indicate the state primacy agency. For real-time water quality information, contact WATER & SEWER COMMISSION 4 OF ST MARY directly or review their annual Consumer Confidence Report (CCR).