Manganese is widespread in Lafayette Parish wells.
1 widespread, 1 worth checking, 5 rare out of 7 health checks.
From 38 wells tested in Lafayette Parish since 2000; your own well needs its own test. How to read this
Rare: under 5%Worth checking: 5 to 15%Widespread: 15%+
Lab results: Water Quality Portal (USGS and EPA)
Who drinks from a well here
1 in 6 people 41,105 people
Nobody else tests these wells. Only you do.
People on wells: EPA researchers' 2020 estimate
How deep wells go here
Middle depth: some shelter from the surface, not complete.
Well depths: US Groundwater Well Database
Radon risk (a gas from rock)
Less likely, but the EPA still says test your air.
Radon zones: EPA map
Here's how Lafayette Parish compares with Louisiana and the counties around it.
Each result puts Lafayette Parish next to the 5 counties that border it, on the chart's 0 to 50% scale.
This one is widespread in Lafayette Parish wells.
Manganese18 of 38 wells over
Too few tested to show: Iberia, St. Landry, St. Martin.
This one is worth checking in Lafayette Parish.
Arsenic3 of 38 wells over
Too few tested to show: Iberia, St. Landry, St. Martin.
These 5 are rare in Lafayette Parish.
Nitrate1 of 38 wells over
Too few tested to show: Iberia, St. Landry, St. Martin, Vermilion.
Lead0 of 38 wells over
Too few tested to show: Iberia, St. Landry, St. Martin.
Fluoride0 of 38 wells over
Too few tested to show: Iberia, St. Landry, St. Martin.
Uranium0 of 38 wells over
Too few tested to show: Iberia, St. Landry, St. Martin, Vermilion.
Radon in water0 of 20 wells over
None of the 2 Lafayette Parish wells tested for bacteria had it, but every well needs a yearly test.
Coliform bacteria0 of 2 wells had it
E. coli0 of 2 wells had it
E. coli means human or animal waste is getting in, so if a test of your Lafayette Parish well finds it, boil drinking water until the well is fixed.
Iron reached staining levels in 12 of 38 tested wells, and it isn't a health risk.
Iron stains12 of 38 wells had it
Too few tested to show: Iberia, St. Landry, St. Martin.
About 7 in 10 of the 38 wells tested in Lafayette Parish have a test from 2020 or later.
With 26 wells tested since 2020, age matters less here than who did the testing and why.
Most Lafayette Parish wells in these records were tested for research or because someone suspected a problem, which can push the shares above what a typical home well would show (how we read the numbers).
One mail-in lab test covers the 4 things to check in Lafayette Parish.
- Bacteria
- Nitrate
- Manganese
- Arsenic
What Louisiana offers well owners
- Free testingWe didn't find a free program for all of Louisiana. Louisiana's private well page
- Certified labsWe didn't find an online list.
- Well recordsLouisiana's well record search
Half the household wells here are shallower than 115 feet.
That comes from 5,115 household wells in Louisiana's drilling records. Most wells of every kind here are 100 to 160 feet deep. Wells as deep as Lafayette Parish's are usually better protected from fertilizer and bacteria at the surface, but they can pick up more of what's in the rock, like arsenic and uranium. Typical household wells here are shallower than in 41 of the 57 other Louisiana counties with enough drilling records.
Look up your own well's depth in Louisiana's well record search, or see how to find it.
Well depths: US Groundwater Well Database
Here's what we know about radon and PFAS in Lafayette Parish.
Lafayette Parish is in the EPA's lowest radon zone, so radon from well water is unlikely to be a problem. Radon guide
Between 2023 and 2025 the EPA had 10 town water systems in Lafayette Parish test for PFAS. None found any. No well in Lafayette Parish has public PFAS results, so the town systems are the best clue to what's in the groundwater nearby. PFAS guide
Radon zones: EPA Map of Radon Zones. PFAS: EPA tests of town water systems, 2023 to 2025
Questions people ask about well water in Lafayette Parish
Is well water in Lafayette Parish safe to drink?
18 of 38 wells tested in Lafayette Parish had manganese over the limit, about 5 in 10. Across Louisiana it's about 2 in 10. That's a bigger share than in 20 of the 23 other Louisiana counties with 10 or more tested wells. So test your own well for manganese before you count on it.
Where can I get my well tested in Lafayette Parish?
Use a lab Louisiana has certified for drinking water. Louisiana's list is linked above, in the box about testing. Ask for bacteria, nitrate, manganese and arsenic, the tests that matter most in Lafayette Parish.
How deep are wells in Lafayette Parish?
Half the household wells here are shallower than 115 feet. Typical household wells here are shallower than in 41 of the 57 other Louisiana counties with enough drilling records.
How does Lafayette Parish compare with the counties around it?
For manganese, the share of tested wells over the limit: Lafayette Parish, at 47%, had a higher share than all 2 neighboring counties with data. Groundwater doesn't stop at county lines, so Vermilion's 40% is worth knowing about if you live near it.
How often should I test my well in Lafayette Parish?
None of the 2 wells tested for bacteria in Lafayette Parish had it, but the CDC still says to test for bacteria and nitrate every year, and right away after a flood, a repair, or any change in taste or smell.
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Where the Lafayette Parish numbers come from
- People on wells: 41,105 in Lafayette Parish, from EPA estimates built on the 2020 Census (Murray et al.).
- Lab tests: 757 well water samples from 38 wells in the Water Quality Portal, run by the USGS and EPA, 2000 to 2021.
- Well depths: 5,115 Louisiana drilling records for Lafayette Parish, gathered in the US Groundwater Well Database (Lin and others, 2024).
- Neighboring counties: the 5 counties that share a border with Lafayette Parish, from the Census Bureau's county adjacency file.
- PFAS: EPA tests of 10 town water systems in Lafayette Parish under the Fifth Unregulated Contaminant Monitoring Rule, 2023 to 2025.
- Radon: Lafayette Parish is zone 3 on the EPA Map of Radon Zones.
- State programs and links: Louisiana Department of Health, checked November 1, 2026.