What was found in St George'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 |
|---|---|---|---|
| Nitrate | 2100 µg/L 21% of the EPA limit 10000 µg/L Main supplier: DIAMOND VALLEY ACRES · 1,340 people · 2019
Highest in the city: 2900 µg/L — WASHINGTON COUNTY WCD - SAND HOLLOW · 425 people · 2019 | 7/7 | SYR4 |
| Nitrate-Nitrite | 1800 µg/L 18% of the EPA limit 10000 µg/L Main supplier: DIAMOND VALLEY ACRES · 1,340 people · 2013 | 4/7 | SYR4 |
| Fluoride | 400 µg/L 10% of the EPA limit 4000 µg/L Main supplier: DIAMOND VALLEY ACRES · 1,340 people · 2019
Highest in the city: 1736.64 µg/L — WINCHESTER HILLS WATER CO · 950 people · 2019 | 6/7 | SYR4 |
| Barium | 195.26 µg/L 9.8% of the EPA limit 2000 µg/L Main supplier: DIAMOND VALLEY ACRES · 1,340 people · 2019
Highest in the city: 375.48 µg/L — WASHINGTON COUNTY WCD - COTTAM · 130 people · 2019 | 7/7 | SYR4 |
| Nitrite | 200 µg/L 20% of the EPA limit 1000 µg/L Highest in the city: PINE VALLEY IRRIGATION CO · 50 people · 2013 | 1/7 | SYR4 |
| Copper | 89.55 µg/L 6.9% of the EPA limit 1300 µg/L Main supplier: DIAMOND VALLEY ACRES · 1,340 people · 2017
Highest in the city: 170.57 µg/L — WASHINGTON COUNTY WCD - COTTAM · 130 people · 2019 | 6/7 | SYR4 |
| TTHM | 42.05 µg/L 53% of the EPA limit 80 µg/L Highest in the city: WASHINGTON COUNTY WCD - QUAIL LAKE · 0 people · 2019 | 4/7 | SYR4 |
| Gross Beta Particle Activity | 8.35 pCi/L No EPA limit set Main supplier: DIAMOND VALLEY ACRES · 1,340 people · 2019
Highest in the city: 22 pCi/L — WINCHESTER HILLS WATER CO · 950 people · 2019 | 7/7 | SYR4 |
| Combined Radium (-226 And -228) | 18.225 pCi/L 365% of the EPA limit, at the 95th percentile of samples — 5 pCi/L Main supplier: DIAMOND VALLEY ACRES · 1,340 people · 2019 | 4/7 | SYR4 |
| Dibromochloromethane | 15.7 µg/L No EPA limit set Highest in the city: WASHINGTON COUNTY WCD - KAYENTA WATER · 0 people · 2019 | 4/7 | SYR4 |
| Chloroform | 14.445 µg/L No EPA limit set Highest in the city: WASHINGTON COUNTY WCD - QUAIL LAKE · 0 people · 2019 | 3/7 | SYR4 |
| Bromodichloromethane | 14.175 µg/L No EPA limit set Highest in the city: WASHINGTON COUNTY WCD - QUAIL LAKE · 0 people · 2019 | 3/7 | SYR4 |
| Arsenic | 1.76 µg/L 18% of the EPA limit 10 µg/L Main supplier: DIAMOND VALLEY ACRES · 1,340 people · 2019
Highest in the city: 13.5 µg/L — WASHINGTON COUNTY WCD - SAND HOLLOW · 425 people · 2019 | 7/7 | SYR4 |
| Bromoform | 11.075 µg/L No EPA limit set Highest in the city: WASHINGTON COUNTY WCD - KAYENTA WATER · 0 people · 2019 | 4/7 | SYR4 |
| Lead | 10.8 µg/L 72% of the EPA limit 15 µg/L Main supplier: DIAMOND VALLEY ACRES · 1,340 people · 2017 | 6/7 | SYR4 |
| Total Haloacetic Acids (HAA5) | 10.76 µg/L 18% of the EPA limit 60 µg/L Highest in the city: WASHINGTON COUNTY WCD - QUAIL LAKE · 0 people · 2019 | 3/7 | SYR4 |
| Gross Alpha, Excl. Radon And U | 8.42 pCi/L 56% of the EPA limit 15 pCi/L Main supplier: DIAMOND VALLEY ACRES · 1,340 people · 2019 | 7/7 | SYR4 |
| Selenium | 3.385 µg/L 6.8% of the EPA limit 50 µg/L Main supplier: DIAMOND VALLEY ACRES · 1,340 people · 2019
Highest in the city: 6.975 µg/L — WASHINGTON COUNTY WCD - SAND HOLLOW · 425 people · 2019 | 7/7 | SYR4 |
| Dichloroacetic Acid | 5.225 µg/L No EPA limit set Highest in the city: WASHINGTON COUNTY WCD - QUAIL LAKE · 0 people · 2016 | 3/7 | SYR4 |
| Dibromoacetic Acid | 5.06 µg/L No EPA limit set Highest in the city: WASHINGTON COUNTY WCD - KAYENTA WATER · 0 people · 2019 | 3/7 | SYR4 |
| Trichloroacetic Acid | 4.12 µg/L No EPA limit set Highest in the city: WASHINGTON COUNTY WCD - QUAIL LAKE · 0 people · 2016 | 3/7 | SYR4 |
| Cyanide | 2 µg/L 1% of the EPA limit 200 µg/L Main supplier: DIAMOND VALLEY ACRES · 1,340 people · 2019
Highest in the city: 4 µg/L — WASHINGTON COUNTY WCD - KAYENTA WATER · 0 people · 2019 | 4/7 | SYR4 |
| Chromium | 3.1 µg/L 3.1% of the EPA limit 100 µg/L Highest in the city: WASHINGTON COUNTY WCD - KAYENTA WATER · 0 people · 2019 | 1/7 | SYR4 |
| Di(2-ethylhexyl) Phthalate | 2.59 µg/L 43% of the EPA limit 6 µg/L Highest in the city: PINE VALLEY IRRIGATION CO · 50 people · 2019 | 1/7 | SYR4 |
| Tetrachloroethylene | 1 µg/L 20% of the EPA limit 5 µg/L Highest in the city: WASHINGTON COUNTY WCD - KAYENTA WATER · 0 people · 2019 | 1/7 | SYR4 |
| Thallium, Total | 0.9850 µg/L 49% of the EPA limit 2 µg/L Highest in the city: WINCHESTER HILLS WATER CO · 950 people · 2019 | 1/7 | SYR4 |
| Lead | 0.0012 mg/L 8% of the EPA limit 0.0150 mg/L Main supplier: DIAMOND VALLEY ACRES · 1,340 people · 2025
Highest in the city: 0.0038 mg/L — PINE VALLEY IRRIGATION CO · 50 people · 2026 | 5/7 | 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 George
| Supplier | Population served |
|---|---|
| DIAMOND VALLEY ACRES | 1,340 |
| WINCHESTER HILLS WATER CO | 950 |
| WASHINGTON COUNTY WCD - SAND HOLLOW | 425 |
| WASHINGTON COUNTY WCD - COTTAM | 130 |
| PINE VALLEY IRRIGATION CO | 50 |
| WASHINGTON COUNTY WCD - KAYENTA WATER | 0 |
| WASHINGTON COUNTY WCD - QUAIL LAKE | 0 |
Frequently asked questions about St George tap water
Is St George tap water safe to drink?
EPA testing detected 27 contaminants in the water serving St George. 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 George?
7 public water suppliers report drinking-water monitoring for St George, Utah to the EPA. Each is listed above with its population served.
What contaminants are in St George's water?
The contaminants EPA monitoring detected in St George include Nitrate, Nitrate-Nitrite, Fluoride, Barium, Nitrite. 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.