What was found in Cottonwood'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 | 579 µg/L 5.8% of the EPA limit 10000 µg/L Main supplier: COTTONWOOD MUNICIPAL WATER CW1 · 11,023 people · 2019
Highest in the city: 9200 µg/L — ACME WATER - BLUE HILLS · 138 people · 2019 | 10/10 | SYR4 |
| Nitrate-Nitrite | 510 µg/L 5.1% of the EPA limit 10000 µg/L Main supplier: COTTONWOOD MUNICIPAL WATER CW1 · 11,023 people · 2018
Highest in the city: 6900 µg/L — ACME WATER - BLUE HILLS · 138 people · 2013 | 7/10 | SYR4 |
| Fluoride | 425 µg/L 11% of the EPA limit 4000 µg/L Main supplier: COTTONWOOD MUNICIPAL WATER CW1 · 11,023 people · 2018
Highest in the city: 727.5 µg/L — ACME WATER - BLUE HILLS · 138 people · 2018 | 9/10 | SYR4 |
| Barium | 610 µg/L 31% of the EPA limit 2000 µg/L Main supplier: COTTONWOOD MUNICIPAL WATER CW1 · 11,023 people · 2018
Highest in the city: 653.5 µg/L — COTTONWOOD MUNICIPAL WATER VV6 · 4,509 people · 2019 | 9/10 | SYR4 |
| Copper | 317 µg/L 24% of the EPA limit 1300 µg/L Main supplier: COTTONWOOD MUNICIPAL WATER CW1 · 11,023 people · 2017
Highest in the city: 402 µg/L — COTTONWOOD MUNICIPAL WATER VV2 · 2,893 people · 2019 | 9/10 | SYR4 |
| Arsenic | 9.72 µg/L 97% of the EPA limit 10 µg/L Main supplier: COTTONWOOD MUNICIPAL WATER CW1 · 11,023 people · 2019
Highest in the city: 61.2 µg/L — RIO VERDE RV PARK · 90 people · 2019 | 10/10 | SYR4 |
| Lithium | 51.5 µg/L No EPA limit set Main supplier: COTTONWOOD MUNICIPAL WATER CW1 · 11,023 people · 2025
Highest in the city: 59 µg/L — COTTONWOOD MUNICIPAL WATER VV6 · 4,509 people · 2025 | 2/10 | UCMR-5 |
| TTHM | 9.32 µg/L 12% of the EPA limit 80 µg/L Main supplier: COTTONWOOD MUNICIPAL WATER CW1 · 11,023 people · 2019
Highest in the city: 31.64 µg/L — ON THE GREENS · 173 people · 2017 | 8/10 | SYR4 |
| Total Haloacetic Acids (HAA5) | 1.385 µg/L 2.3% of the EPA limit 60 µg/L Main supplier: COTTONWOOD MUNICIPAL WATER CW1 · 11,023 people · 2019
Highest in the city: 16 µg/L — ON THE GREENS · 173 people · 2017 | 3/10 | SYR4 |
| Chromium | 12.6 µg/L 13% of the EPA limit 100 µg/L Main supplier: COTTONWOOD MUNICIPAL WATER CW1 · 11,023 people · 2018
Highest in the city: 14.5 µg/L — Cottonwood Day School BIA · 185 people · 2018 | 8/10 | SYR4 |
| Combined Uranium | 13 µg/L 43% of the EPA limit 30 µg/L Highest in the city: Cottonwood Day School BIA · 185 people · 2014 | 1/10 | SYR4 |
| Thallium, Total | 11 µg/L 550% of the EPA limit, at the 95th percentile of samples — 2 µg/L Highest in the city: COTTONWOOD MUNICIPAL WATER VV2 · 2,893 people · 2019 | 1/10 | SYR4 |
| Lead | 4.895 µg/L 33% of the EPA limit 15 µg/L Main supplier: COTTONWOOD MUNICIPAL WATER CW1 · 11,023 people · 2017
Highest in the city: 10.03 µg/L — COTTONWOOD MUNICIPAL WATER VV3 · 1,458 people · 2019 | 8/10 | SYR4 |
| Selenium | 6.9 µg/L 14% of the EPA limit 50 µg/L Highest in the city: ON THE GREENS · 173 people · 2017 | 2/10 | SYR4 |
| Cyanide | 5.3 µg/L 2.7% of the EPA limit 200 µg/L Highest in the city: RIO VERDE RV PARK · 90 people · 2017 | 1/10 | SYR4 |
| Toluene | 4.7 µg/L 0.5% of the EPA limit 1000 µg/L Highest in the city: ON THE GREENS · 173 people · 2019 | 1/10 | SYR4 |
| Bromoform | 4.4 µg/L No EPA limit set Main supplier: COTTONWOOD MUNICIPAL WATER CW1 · 11,023 people · 2019 | 2/10 | SYR4 |
| Dibromochloromethane | 3 µg/L No EPA limit set Main supplier: COTTONWOOD MUNICIPAL WATER CW1 · 11,023 people · 2019 | 2/10 | SYR4 |
| Xylenes, Total | 1.865 µg/L 0% of the EPA limit 10000 µg/L Main supplier: COTTONWOOD MUNICIPAL WATER CW1 · 11,023 people · 2019
Highest in the city: 2.3 µg/L — RIO VERDE RV PARK · 90 people · 2019 | 4/10 | SYR4 |
| Tetrachloroethylene | 1.52 µg/L 30% of the EPA limit 5 µg/L Highest in the city: ACME WATER - BLUE HILLS · 138 people · 2019 | 1/10 | SYR4 |
| Bromodichloromethane | 1.2 µg/L No EPA limit set Main supplier: COTTONWOOD MUNICIPAL WATER CW1 · 11,023 people · 2019 | 1/10 | SYR4 |
| Dibromoacetic Acid | 1.2 µg/L No EPA limit set Main supplier: COTTONWOOD MUNICIPAL WATER CW1 · 11,023 people · 2019 | 1/10 | SYR4 |
| Gross Alpha, Excl. Radon And U | 1.06 pCi/L 7.1% of the EPA limit 15 pCi/L Highest in the city: Cottonwood Day School BIA · 185 people · 2014 | 1/10 | SYR4 |
| Combined Radium (-226 And -228) | 0.6000 pCi/L 12% of the EPA limit 5 pCi/L Main supplier: COTTONWOOD MUNICIPAL WATER CW1 · 11,023 people · 2019 | 4/10 | SYR4 |
| Lead | 0.0 mg/L 0% of the EPA limit 0.0150 mg/L Main supplier: COTTONWOOD MUNICIPAL WATER CW1 · 11,023 people · 2023
Highest in the city: 0.0070 mg/L — C-OASIS PARK · 54 people · 2025 | 10/10 | LCR |
| Pfpea | 0.0032 µg/L No EPA limit set Main supplier: COTTONWOOD MUNICIPAL WATER CW1 · 11,023 people · 2025 | 1/10 | UCMR-5 |
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 Cottonwood
| Supplier | Population served |
|---|---|
| COTTONWOOD MUNICIPAL WATER CW1 | 11,023 |
| COTTONWOOD MUNICIPAL WATER VV6 | 4,509 |
| COTTONWOOD MUNICIPAL WATER VV2 | 2,893 |
| COTTONWOOD MUNICIPAL WATER VV3 | 1,458 |
| VERDE VALLEY MANOR | 275 |
| Cottonwood Day School BIA | 185 |
| ON THE GREENS | 173 |
| ACME WATER - BLUE HILLS | 138 |
| RIO VERDE RV PARK | 90 |
| C-OASIS PARK | 54 |
Frequently asked questions about Cottonwood tap water
Is Cottonwood tap water safe to drink?
EPA testing detected 26 contaminants in the water serving Cottonwood. 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 Cottonwood?
10 public water suppliers report drinking-water monitoring for Cottonwood, Arizona to the EPA. Each is listed above with its population served.
What contaminants are in Cottonwood's water?
The contaminants EPA monitoring detected in Cottonwood include Nitrate, Nitrate-Nitrite, Fluoride, Barium, Copper. 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.