Compliance record
PFAS detected
PFAS are industrial “forever chemicals”. These are the EPA's latest
nationwide test results (2023–2025).
Other contaminants detected
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 this
system's samples — over 100% is worth reading, but is not by itself a
violation. Where a single sample came in higher than that percentile, it
is noted under the bar. Formal violations are listed separately.
| Contaminant | Level vs EPA limit | Detection rate | Source | Period |
|---|---|---|---|---|
| TTHM | 63.305 µg/L 79% of the EPA limit 80 µg/L
worst single sample: 104 µg/L | 492/492 | SYR4 | 2012–2019 |
| Total Haloacetic Acids (HAA5) | 40.7 µg/L 68% of the EPA limit 60 µg/L
worst single sample: 60.5 µg/L | 489/492 | SYR4 | 2012–2019 |
| Bromodichloromethane | 12.7 µg/L No EPA limit set
worst single sample: 21.8 µg/L | 484/484 | SYR4 | 2012–2019 |
| Chloroform | 47.57 µg/L No EPA limit set
worst single sample: 86.4 µg/L | 484/484 | SYR4 | 2012–2019 |
| Dibromochloromethane | 6.6695 µg/L No EPA limit set
worst single sample: 8.84 µg/L | 484/484 | SYR4 | 2012–2019 |
| Dichloroacetic Acid | 22.115 µg/L No EPA limit set
worst single sample: 33.2 µg/L | 480/484 | SYR4 | 2012–2019 |
| Trichloroacetic Acid | 17.5 µg/L No EPA limit set
worst single sample: 26.2 µg/L | 434/484 | SYR4 | 2012–2019 |
| Nitrate | 1610 µg/L 16% of the EPA limit 10000 µg/L
worst single sample: 2510 µg/L | 404/404 | SYR4 | 2012–2019 |
| Dibromoacetic Acid | 2.329 µg/L No EPA limit set
worst single sample: 3.13 µg/L | 272/484 | SYR4 | 2012–2019 |
| Bromoform | 1.41 µg/L No EPA limit set
worst single sample: 1.67 µg/L | 221/484 | SYR4 | 2012–2019 |
| Nitrate-Nitrite | 1614 µg/L 16% of the EPA limit 10000 µg/L
worst single sample: 2520 µg/L | 197/197 | SYR4 | 2012–2019 |
| Fluoride | 800 µg/L 20% of the EPA limit 4000 µg/L | 158/164 | SYR4 | 2012–2019 |
| Copper | 190 µg/L 15% of the EPA limit 1300 µg/L
worst single sample: 558 µg/L | 126/285 | SYR4 | 2012–2019 |
| Lead | 1.09 µg/L 7.3% of the EPA limit 15 µg/L
worst single sample: 2.4 µg/L | 83/187 | SYR4 | 2012–2019 |
| Barium | 48.16 µg/L 2.4% of the EPA limit 2000 µg/L
worst single sample: 53.2 µg/L | 53/63 | SYR4 | 2012–2019 |
| Monochloroacetic Acid | 3.737 µg/L No EPA limit set
worst single sample: 4 µg/L | 42/484 | SYR4 | 2012–2019 |
| Nitrite | 20 µg/L 2% of the EPA limit 1000 µg/L | 27/371 | SYR4 | 2012–2019 |
| Bromate | 8.9 µg/L 89% of the EPA limit 10 µg/L
worst single sample: 10 µg/L | 23/638 | SYR4 | 2012–2019 |
| Lead | 0.0012 mg/L 8% of the EPA limit 0.0150 mg/L | 17/17 | LCR | 2023 |
| Gross Beta Particle Activity | 5.55 pCi/L No EPA limit set
worst single sample: 5.99 pCi/L | 9/19 | SYR4 | 2013–2019 |
| Atrazine | 0.0875 µg/L 2.9% of the EPA limit 3 µg/L
worst single sample: 0.0900 µg/L | 3/12 | SYR4 | 2012–2017 |
| Combined Radium (-226 And -228) | 0.6501 pCi/L 13% of the EPA limit 5 pCi/L
worst single sample: 0.6910 pCi/L | 3/11 | SYR4 | 2013–2019 |
| Combined Uranium | 0.1120 µg/L 0.4% of the EPA limit 30 µg/L | 1/11 | SYR4 | 2013–2019 |
| Gross Alpha, Excl. Radon And U | 3.01 pCi/L 20% of the EPA limit 15 pCi/L | 1/9 | SYR4 | 2013–2019 |
79 contaminants tested, none detected
1,1,1-Trichloroethane1,1,2-Trichloroethane1,1-Dichloroethylene1,2,4-Trichlorobenzene1,2-DIBROMO-3-CHLOROPROPANE1,2-Dichloroethane1,2-Dichloropropane11Cl-PF3OUdS2,4,5-TP2,4-D4:2 Fts8:2 Fts9Cl-PF3ONSAdonaAntimony, TotalArsenicBhc-GammaBenzeneBenzo(A)PyreneBeryllium, TotalChlorobenzeneCyanideCadmiumCarbofuranCarbon TetrachlorideChlordaneChromiumDichloromethaneDalaponDi(2-ethylhexyl) AdipateDi(2-ethylhexyl) PhthalateDinosebDiquatEthylene DibromideEndrinEthylbenzeneHexachlorobenzeneHfpo-DaHeptachlorHeptachlor EpoxideHexachlorocyclopentadieneLassoMercuryMethoxychlorMonobromoacetic AcidNetfosaaNfdhaNmefosaaOxamylPfdaPfdoaPfeesaPfhpsPFHXSPfmbaPfmpaPFNAPfpesPftaPftrdaPfunaPentachlorophenolPicloramSeleniumSimazineStyreneTetrachloroethyleneThallium, TotalTolueneTotal Polychlorinated Biphenyls (PCB)ToxapheneTrichloroethyleneVinyl ChlorideXylenes, Totalcis-1,2-DichloroethyleneLithiumO-DichlorobenzeneP-Dichlorobenzenetrans-1,2-Dichloroethylene
Utility contact
Frequently asked questions about Fairfax County Water Authority
Is Fairfax County Water Authority tap water safe to drink?
EPA monitoring detected 32 contaminants in Fairfax County Water Authority's water. A detection isn't the same as a violation — most levels are within federal limits. See each level and source above, and the utility's annual Consumer Confidence Report for its official compliance status.
What contaminants were detected in Fairfax County Water Authority's water?
EPA monitoring detected TTHM, Total Haloacetic Acids (HAA5), Bromodichloromethane, Chloroform, Dibromochloromethane, and others. The full list with the level and data source for each is above.
How many people does Fairfax County Water Authority serve?
Fairfax County Water Authority reports serving 1,121,613 people in Virginia, per its EPA record.
Has Fairfax County Water Authority had any water quality violations?
The EPA has no formal drinking-water violations on file for Fairfax County Water Authority.
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.