What was found in Cary'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 | 3400 µg/L 34% of the EPA limit 10000 µg/L Highest in the city: MEDFIELD ESTATES S/D · 772 people · 2019 | 4/13 | SYR4 |
| Nitrate-Nitrite | 3380 µg/L 34% of the EPA limit 10000 µg/L Highest in the city: MEDFIELD ESTATES S/D · 772 people · 2019 | 4/13 | SYR4 |
| Copper | 214 µg/L 16% of the EPA limit 1300 µg/L Main supplier: CARY, TOWN OF · 227,300 people · 2019
Highest in the city: 889.85 µg/L — MEDFIELD ESTATES S/D · 772 people · 2017 | 9/13 | SYR4 |
| Fluoride | 806.5 µg/L 20% of the EPA limit 4000 µg/L Main supplier: CARY, TOWN OF · 227,300 people · 2019 | 9/13 | SYR4 |
| Lead | 78.74 µg/L 525% of the EPA limit, at the 95th percentile of samples — 15 µg/L Main supplier: CARY, TOWN OF · 227,300 people · 2019
Highest in the city: 117.162 µg/L — MEDFIELD ESTATES S/D · 772 people · 2017 | 6/13 | SYR4 |
| TTHM | 65 µg/L 81% of the EPA limit 80 µg/L Main supplier: CARY, TOWN OF · 227,300 people · 2019
Highest in the city: 65.45 µg/L — MOBILE ESTATES · 690 people · 2019 | 9/13 | SYR4 |
| Chloroform | 29.65 µg/L No EPA limit set Main supplier: CARY, TOWN OF · 227,300 people · 2019
Highest in the city: 30.55 µg/L — CHATHAM ESTATES MHP · 366 people · 2019 | 7/13 | SYR4 |
| Total Haloacetic Acids (HAA5) | 25 µg/L 42% of the EPA limit 60 µg/L Main supplier: CARY, TOWN OF · 227,300 people · 2019 | 5/13 | SYR4 |
| Bromodichloromethane | 22.65 µg/L No EPA limit set Main supplier: CARY, TOWN OF · 227,300 people · 2019 | 5/13 | SYR4 |
| Dibromochloromethane | 20 µg/L No EPA limit set Main supplier: CARY, TOWN OF · 227,300 people · 2019 | 5/13 | SYR4 |
| Dichloroacetic Acid | 16 µg/L No EPA limit set Main supplier: CARY, TOWN OF · 227,300 people · 2019 | 6/13 | SYR4 |
| Bromate | 13.75 µg/L 138% of the EPA limit, at the 95th percentile of samples — 10 µg/L Main supplier: CARY, TOWN OF · 227,300 people · 2019 | 1/13 | SYR4 |
| Trichloroacetic Acid | 7.27 µg/L No EPA limit set Main supplier: CARY, TOWN OF · 227,300 people · 2019
Highest in the city: 9.08 µg/L — MOBILE ESTATES · 690 people · 2019 | 3/13 | SYR4 |
| Combined Radium (-226 And -228) | 6.595 pCi/L 132% of the EPA limit, at the 95th percentile of samples — 5 pCi/L Highest in the city: OLDE SOUTH TRACE SD · 76 people · 2018 | 5/13 | SYR4 |
| Gross Beta Particle Activity | 4.2 pCi/L No EPA limit set Main supplier: CARY, TOWN OF · 227,300 people · 2017
Highest in the city: 6.495 pCi/L — OLDE SOUTH TRACE SD · 76 people · 2019 | 7/13 | SYR4 |
| Bromoform | 5.4 µg/L No EPA limit set Main supplier: CARY, TOWN OF · 227,300 people · 2019 | 5/13 | SYR4 |
| Dibromoacetic Acid | 4.41 µg/L No EPA limit set Main supplier: CARY, TOWN OF · 227,300 people · 2019
Highest in the city: 5.33 µg/L — MOBILE ESTATES · 690 people · 2019 | 4/13 | SYR4 |
| Monochloroacetic Acid | 4.4 µg/L No EPA limit set Highest in the city: MOBILE ESTATES · 690 people · 2019 | 2/13 | SYR4 |
| Monobromoacetic Acid | 3.34 µg/L No EPA limit set Main supplier: CARY, TOWN OF · 227,300 people · 2019
Highest in the city: 3.625 µg/L — MOBILE ESTATES · 690 people · 2019 | 3/13 | SYR4 |
| Dalapon | 1.6 µg/L 0.8% of the EPA limit 200 µg/L Main supplier: CARY, TOWN OF · 227,300 people · 2017 | 1/13 | SYR4 |
| Combined Uranium | 1.2963 µg/L 4.3% of the EPA limit 30 µg/L Highest in the city: HONEYCUTT LANDING S/D · 473 people · 2016 | 1/13 | SYR4 |
| Dichloromethane | 1.1 µg/L 22% of the EPA limit 5 µg/L Highest in the city: SWIFT CREEK MASTER SYSTEM · 465 people · 2019 | 1/13 | SYR4 |
| Xylenes, Total | 0.7700 µg/L 0% of the EPA limit 10000 µg/L Highest in the city: SWIFT CREEK MASTER SYSTEM · 465 people · 2019 | 1/13 | SYR4 |
| Heptachlor Epoxide | 0.0406 µg/L 20% of the EPA limit 0.2000 µg/L Highest in the city: MEDFIELD ESTATES S/D · 772 people · 2019 | 1/13 | SYR4 |
| Pfba | 0.0073 µg/L No EPA limit set Main supplier: CARY, TOWN OF · 227,300 people · 2025 | 1/13 | UCMR-5 |
| Lead | 0.0 mg/L 0% of the EPA limit 0.0150 mg/L Main supplier: CARY, TOWN OF · 227,300 people · 2025
Highest in the city: 0.0072 mg/L — MEDFIELD ESTATES S/D · 772 people · 2025 | 13/13 | LCR |
| Pfpea | 0.0070 µg/L No EPA limit set Main supplier: CARY, TOWN OF · 227,300 people · 2025 | 1/13 | UCMR-5 |
| Pfhxa | 0.0066 µg/L No EPA limit set Main supplier: CARY, TOWN OF · 227,300 people · 2025 | 1/13 | UCMR-5 |
| PFBS | 0.0034 µg/L No EPA limit set Main supplier: CARY, TOWN OF · 227,300 people · 2025 | 1/13 | 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 Cary
| Supplier | Population served |
|---|---|
| CARY, TOWN OF | 227,300 |
| MEDFIELD ESTATES S/D | 772 |
| MOBILE ESTATES | 690 |
| HONEYCUTT LANDING S/D | 473 |
| SWIFT CREEK MASTER SYSTEM | 465 |
| SEDGEMOOR S/D | 435 |
| CHATHAM ESTATES MHP | 366 |
| WEDGEWOOD SQUARE S/D | 96 |
| GREYTHORNE S/D | 94 |
| OLDE SOUTH TRACE SD | 76 |
| HARMONY GLEN S/D | 74 |
| BIRKLANDS S/D | 64 |
| ASHEBROOK S/D | 53 |
Frequently asked questions about Cary tap water
Is Cary tap water safe to drink?
EPA testing detected 29 contaminants in the water serving Cary. 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 Cary?
13 public water suppliers report drinking-water monitoring for Cary, North Carolina to the EPA. Each is listed above with its population served.
What contaminants are in Cary's water?
The contaminants EPA monitoring detected in Cary include Nitrate, Nitrate-Nitrite, Copper, Fluoride, Lead. 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.