What was found in St Joseph's water
The level at the city's main supplier, the highest level anywhere in the city, the EPA limit for each, and where every figure comes from.
| Contaminant | Level vs EPA limit | Suppliers | Source |
|---|---|---|---|
| Copper | 1630 µg/L 125% of the EPA limit, at the 95th percentile of samples — 1300 µg/L Main supplier: TENSAS WATER DISTRICT ASSOCIATION · 3,843 people · 2019 | 2/2 | SYR4 |
| Barium | 59.6 µg/L 3% of the EPA limit 2000 µg/L Main supplier: TENSAS WATER DISTRICT ASSOCIATION · 3,843 people · 2019
Highest in the city: 1000 µg/L — TOWN OF ST JOSEPH WATER SYSTEM · 1,332 people · 2019 | 2/2 | SYR4 |
| Nitrate-Nitrite | 670 µg/L 6.7% of the EPA limit 10000 µg/L Main supplier: TENSAS WATER DISTRICT ASSOCIATION · 3,843 people · 2019
Highest in the city: 1000 µg/L — TOWN OF ST JOSEPH WATER SYSTEM · 1,332 people · 2019 | 2/2 | SYR4 |
| Fluoride | 97.75 µg/L 2.4% of the EPA limit 4000 µg/L Main supplier: TENSAS WATER DISTRICT ASSOCIATION · 3,843 people · 2019
Highest in the city: 366 µg/L — TOWN OF ST JOSEPH WATER SYSTEM · 1,332 people · 2018 | 2/2 | SYR4 |
| TTHM | 60.6 µg/L 76% of the EPA limit 80 µg/L Main supplier: TENSAS WATER DISTRICT ASSOCIATION · 3,843 people · 2019
Highest in the city: 134.33 µg/L — TOWN OF ST JOSEPH WATER SYSTEM · 1,332 people · 2019 | 2/2 | SYR4 |
| Chloroform | 55.6 µg/L No EPA limit set Main supplier: TENSAS WATER DISTRICT ASSOCIATION · 3,843 people · 2019
Highest in the city: 83.19 µg/L — TOWN OF ST JOSEPH WATER SYSTEM · 1,332 people · 2019 | 2/2 | SYR4 |
| Dalapon | 75.281 µg/L 38% of the EPA limit 200 µg/L Main supplier: TENSAS WATER DISTRICT ASSOCIATION · 3,843 people · 2019
Highest in the city: 80.36 µg/L — TOWN OF ST JOSEPH WATER SYSTEM · 1,332 people · 2018 | 2/2 | SYR4 |
| Total Haloacetic Acids (HAA5) | 60.59 µg/L 101% of the EPA limit, at the 95th percentile of samples — 60 µg/L Main supplier: TENSAS WATER DISTRICT ASSOCIATION · 3,843 people · 2019
Highest in the city: 68.935 µg/L — TOWN OF ST JOSEPH WATER SYSTEM · 1,332 people · 2019 | 2/2 | SYR4 |
| Bromodichloromethane | 4.03 µg/L No EPA limit set Main supplier: TENSAS WATER DISTRICT ASSOCIATION · 3,843 people · 2019
Highest in the city: 37.775 µg/L — TOWN OF ST JOSEPH WATER SYSTEM · 1,332 people · 2019 | 2/2 | SYR4 |
| Dichloroacetic Acid | 35 µg/L No EPA limit set Main supplier: TENSAS WATER DISTRICT ASSOCIATION · 3,843 people · 2019 | 2/2 | SYR4 |
| Trichloroacetic Acid | 24.92 µg/L No EPA limit set Main supplier: TENSAS WATER DISTRICT ASSOCIATION · 3,843 people · 2019
Highest in the city: 33.28 µg/L — TOWN OF ST JOSEPH WATER SYSTEM · 1,332 people · 2019 | 2/2 | SYR4 |
| Lead | 8 µg/L 53% of the EPA limit 15 µg/L Main supplier: TENSAS WATER DISTRICT ASSOCIATION · 3,843 people · 2019
Highest in the city: 15.2 µg/L — TOWN OF ST JOSEPH WATER SYSTEM · 1,332 people · 2019 | 2/2 | SYR4 |
| Dibromochloromethane | 6.55 µg/L No EPA limit set Main supplier: TENSAS WATER DISTRICT ASSOCIATION · 3,843 people · 2019
Highest in the city: 14.8 µg/L — TOWN OF ST JOSEPH WATER SYSTEM · 1,332 people · 2019 | 2/2 | SYR4 |
| Monobromoacetic Acid | 11.53 µg/L No EPA limit set Main supplier: TENSAS WATER DISTRICT ASSOCIATION · 3,843 people · 2019 | 2/2 | SYR4 |
| Monochloroacetic Acid | 3.6 µg/L No EPA limit set Main supplier: TENSAS WATER DISTRICT ASSOCIATION · 3,843 people · 2019
Highest in the city: 10.3 µg/L — TOWN OF ST JOSEPH WATER SYSTEM · 1,332 people · 2019 | 2/2 | SYR4 |
| Arsenic | 1.39 µg/L 14% of the EPA limit 10 µg/L Main supplier: TENSAS WATER DISTRICT ASSOCIATION · 3,843 people · 2019
Highest in the city: 8.1 µg/L — TOWN OF ST JOSEPH WATER SYSTEM · 1,332 people · 2019 | 2/2 | SYR4 |
| Gross Beta Particle Activity | 3.865 pCi/L No EPA limit set Main supplier: TENSAS WATER DISTRICT ASSOCIATION · 3,843 people · 2019
Highest in the city: 5.73 pCi/L — TOWN OF ST JOSEPH WATER SYSTEM · 1,332 people · 2018 | 2/2 | SYR4 |
| Gross Alpha, Excl. Radon And U | 3.34 pCi/L 22% of the EPA limit 15 pCi/L Highest in the city: TOWN OF ST JOSEPH WATER SYSTEM · 1,332 people · 2016 | 1/2 | SYR4 |
| Dibromoacetic Acid | 1.775 µg/L No EPA limit set Main supplier: TENSAS WATER DISTRICT ASSOCIATION · 3,843 people · 2019
Highest in the city: 3.24 µg/L — TOWN OF ST JOSEPH WATER SYSTEM · 1,332 people · 2019 | 2/2 | SYR4 |
| Combined Radium (-226 And -228) | 2.353 pCi/L 47% of the EPA limit 5 pCi/L Highest in the city: TOWN OF ST JOSEPH WATER SYSTEM · 1,332 people · 2018 | 1/2 | SYR4 |
| Atrazine | 1.6945 µg/L 56% of the EPA limit 3 µg/L Main supplier: TENSAS WATER DISTRICT ASSOCIATION · 3,843 people · 2019 | 1/2 | SYR4 |
| Bromoform | 0.5500 µg/L No EPA limit set Main supplier: TENSAS WATER DISTRICT ASSOCIATION · 3,843 people · 2019
Highest in the city: 1.22 µg/L — TOWN OF ST JOSEPH WATER SYSTEM · 1,332 people · 2019 | 2/2 | SYR4 |
| Di(2-ethylhexyl) Phthalate | 1.046 µg/L 17% of the EPA limit 6 µg/L Main supplier: TENSAS WATER DISTRICT ASSOCIATION · 3,843 people · 2019 | 2/2 | SYR4 |
| Antimony, Total | 0.7400 µg/L 12% of the EPA limit 6 µg/L Highest in the city: TOWN OF ST JOSEPH WATER SYSTEM · 1,332 people · 2019 | 1/2 | SYR4 |
| Selenium | 0.7075 µg/L 1.4% of the EPA limit 50 µg/L Highest in the city: TOWN OF ST JOSEPH WATER SYSTEM · 1,332 people · 2019 | 1/2 | SYR4 |
| 2,4-D | 0.1500 µg/L 0.2% of the EPA limit 70 µg/L Main supplier: TENSAS WATER DISTRICT ASSOCIATION · 3,843 people · 2019 | 1/2 | SYR4 |
| Pfba | 0.0063 µg/L No EPA limit set Main supplier: TENSAS WATER DISTRICT ASSOCIATION · 3,843 people · 2024 | 1/2 | UCMR-5 |
| Bhc-Gamma | 0.0061 µg/L 3.1% of the EPA limit 0.2000 µg/L Main supplier: TENSAS WATER DISTRICT ASSOCIATION · 3,843 people · 2019 | 1/2 | SYR4 |
| Lead | 0.0021 mg/L 14% of the EPA limit 0.0150 mg/L Main supplier: TENSAS WATER DISTRICT ASSOCIATION · 3,843 people · 2025
Highest in the city: 0.0030 mg/L — TOWN OF ST JOSEPH WATER SYSTEM · 1,332 people · 2023 | 2/2 | LCR |
Each bar shows the measured level as a share of the EPA limit: green is
well under, amber is close to it, red is over. For lead and copper the
limit applies to exactly the 90th-percentile figure shown, so red there
means a real exceedance. For everything else the limit applies to a
running annual average while the figure is the 95th percentile of the
system's samples — over 100% is worth reading, but is not by itself a
violation.
Formal violations are listed separately.
These are the utilities' own EPA-reported results, not a city-wide
average. A detection means the lab measured the
substance — it isn't the same as exceeding a legal limit. Hover a source
tag to see the EPA program and years behind each figure.
Water suppliers serving St Joseph
| Supplier | Population served |
|---|---|
| TENSAS WATER DISTRICT ASSOCIATION | 3,843 |
| TOWN OF ST JOSEPH WATER SYSTEM | 1,332 |
Frequently asked questions about St Joseph tap water
Is St Joseph tap water safe to drink?
EPA testing detected 29 contaminants in the water serving St Joseph. A detection isn't the same as a violation — most detected levels are within federal limits. Check the level and source for each contaminant above, and your utility's annual Consumer Confidence Report for the official compliance status.
How many water suppliers serve St Joseph?
2 public water suppliers report drinking-water monitoring for St Joseph, Louisiana to the EPA. Each is listed above with its population served.
What contaminants are in St Joseph's water?
The contaminants EPA monitoring detected in St Joseph include Copper, Barium, Nitrate-Nitrite, Fluoride, TTHM. The full list, with the level at the main supplier and the data source, is in the table above.
Where does this data come from?
Every figure is official EPA drinking-water monitoring — the Lead & Copper Rule, the UCMR-5 nationwide testing program, and the EPA Six-Year Review — not our own testing. Each number is labelled with its source and period.