EPA data as of Oct 2026 · page updated 2026-10-29

Home hazard report for 70541 — Grand Coteau, LA

ZIP 70541 is served by Town of Grand Coteau Water System: 14 violations since 2016, latest lead result 5 ppb, PFAS not tested. St. Landry Parish is in EPA radon zone 3.

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Where ZIP 70541 is

Dashed: ZIP area · blue: utility service area · scroll or pinch to zoom
ZIP code areaZIP center Water utility service area PFOA/PFOS ≥ 4 ppt Lead > 15 ppb 5+ violations Superfund site (active) proposed cleaned up Circles: other water systems flagged nearby; size = people served. Tap any symbol for details.

Drinking water: Town of Grand Coteau Water System

EPA IDLA1097001
People served1,650
Sourcegroundwater (wells)
Connections550

Health-based violations

Contaminant or ruleHealth-based violations since 2016
Groundwater Rule13
Lead and Copper Rule Revisions1

A health-based violation means a contaminant exceeded its legal limit (MCL) or a required treatment technique was not met, as reported by the state to EPA’s SDWIS. 1 still listed as unresolved (“unaddressed” or “addressed” but not yet returned to compliance); the latest began Mar 2025.

Full record for Town of Grand Coteau Water System →

Lead

Jan 20265 ppb
Jan 20257 ppb
Jul 20241 ppb
Jan 20241 ppb
Jan 20213 ppb
Jan 20201 ppb
Jan 20194 ppb
Jul 20150 ppb

90th-percentile lead per sampling round (90% of the homes sampled were at or below this level). Black line: EPA’s 15 ppb action level; under the Lead and Copper Rule Improvements the action level becomes 10 ppb from 2027.

PFAS (“forever chemicals”)

This system was not part of EPA’s 2023–2025 nationwide PFAS testing (UCMR 5).

Radon in St. Landry Parish

EPA radon zone 3 — low potential. Predicted average under 2 pCi/L — but any home can have high radon, so EPA still recommends a test.

Radon is a colorless, odorless radioactive gas from soil and rock, and the leading cause of lung cancer among non-smokers. EPA recommends fixing a home at 4 pCi/L or above and considering it from 2 pCi/L. A short-term test kit costs about $15–30. How radon zones work →

Natural hazard risk

FEMA rates the overall natural-hazard risk of this neighborhood (census tract) as Relatively High, with relatively high social vulnerability and relatively high community resilience.

LightningVery High
TornadoVery High
Cold waveRelatively High
HurricaneRelatively High
Riverine floodingRelatively High
DroughtRelatively Moderate
Heat waveRelatively Moderate
Ice stormRelatively Moderate
Strong windRelatively Moderate
Winter weatherRelatively Moderate
HailRelatively Low
WildfireRelatively Low
EarthquakeVery Low
LandslideVery Low

FEMA National Risk Index (December 2025): expected annual losses from each hazard combined with social vulnerability and community resilience, rated relative to all U.S. census tracts. Hazards not listed are not applicable here. It describes the area, not a single building; flood insurance maps (FEMA FIRMs) decide flood-insurance requirements.

Live conditions: river gauges and flood levels · tornado warnings · wildfire detections · earthquakes — our sister maps, updated from NOAA, USGS and NASA every few minutes.

Superfund sites nearby

No site on EPA’s Superfund National Priorities List lies within 10 miles of the center of this ZIP code.

EPA Superfund National Priorities List (NPL): the country’s most serious known hazardous-waste sites, each with an EPA cleanup record (linked). Distance is measured from the ZIP center to the site’s reference point; being near a site does not by itself mean exposure — EPA site pages describe what was found and how it is being cleaned up.

What this is — and isn’t. These are records your water utility and state reported to the EPA, and the EPA’s radon map for your county. They describe the system and the area, not the water from your own tap or the air in your home. For that, read your utility’s annual Consumer Confidence Report and test: lead and radon tests are inexpensive.

Questions about 70541

Who supplies drinking water to ZIP 70541?

Town of Grand Coteau Water System (EPA ID LA1097001), a groundwater (wells) system serving about 1,650 people.

Is there lead in Grand Coteau, LA tap water?

The utility’s latest 90th-percentile lead result (Jan 2026) was 5 ppb; EPA’s action level is 15 ppb, falling to 10 ppb from 2027. Lead mostly comes from service lines and home plumbing, so the only way to know your tap is to test it.

Does Grand Coteau, LA water have PFAS?

This system was not part of EPA’s 2023–2025 nationwide PFAS testing (UCMR 5 covers systems serving over 3,300 people and a sample of smaller ones).

Has the water system in 70541 had violations?

Health-based violations since 2016: Groundwater Rule, Lead and Copper Rule Revisions. 1 is still listed as unresolved in EPA records.

What natural hazards affect ZIP 70541?

FEMA’s National Risk Index rates the overall natural-hazard risk here as Relatively High; the highest-rated hazards are lightning (very high), tornado (very high), cold wave (relatively high).

Are there Superfund sites near 70541?

No active Superfund site within 10 miles of the ZIP center.

Is radon a problem in St. Landry Parish?

St. Landry Parish is in EPA radon zone 3 (low potential). Predicted average under 2 pCi/L — but any home can have high radon, so EPA still recommends a test.