What Total Haloacetic Acids (HAA5) is, and why it's regulated
What the EPA limit means
60 µg/L
Maximum Contaminant Level — the enforceable ceiling a supplier must stay under.
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Health goal (MCLG) — the level with no known health effect. It is a goal, not a legal limit, and is often zero for carcinogens.
SYR4
Where these measurements come from. Hover the tag for the EPA programme and years.
Where Total Haloacetic Acids (HAA5) was found
The water suppliers reporting the highest levels, worst first. For lead and copper that is the 90th-percentile result the action level is written against; for Six-Year Review data, the 95th percentile of each system's samples.
| Supplier | City | State | Level vs EPA limit |
|---|---|---|---|
| Eagle Ridge Personal Care Home | Mill Hall | PA | 2090.08 µg/L 3483% of the EPA limit, at the 95th percentile of samples — 60 µg/L |
| Greenhorn Subd | Ketchum | ID | 1160 µg/L 1933% of the EPA limit, at the 95th percentile of samples — 60 µg/L |
| Vallenar View Mobile Home Park | Ketchikan | AK | 704 µg/L 1173% of the EPA limit, at the 95th percentile of samples — 60 µg/L |
| Murphy Hill Ws #02 | Aromas | CA | 530 µg/L 883% of the EPA limit, at the 95th percentile of samples — 60 µg/L |
| City of Nome | — | TX | 393 µg/L 655% of the EPA limit, at the 95th percentile of samples — 60 µg/L |
| Croft Bay Village | Hernando | MN | 390.065 µg/L 650% of the EPA limit, at the 95th percentile of samples — 60 µg/L |
| Hudson Gaars Mill Water System | Dodson | LA | 388.6 µg/L 648% of the EPA limit, at the 95th percentile of samples — 60 µg/L |
| Titusville Estates | Conneaut Lake | PA | 373.599 µg/L 623% of the EPA limit, at the 95th percentile of samples — 60 µg/L |
| Sandy Point 480 Water System | Campti | LA | 370.1 µg/L 617% of the EPA limit, at the 95th percentile of samples — 60 µg/L |
| Buckland Water System | Buckland | AK | 345.3 µg/L 576% of the EPA limit, at the 95th percentile of samples — 60 µg/L |
| Wenden Dwid | Wenden | AZ | 337.18 µg/L 562% of the EPA limit, at the 95th percentile of samples — 60 µg/L |
| J ; S Fish Camp | Okeechobee | FL | 327.8 µg/L 546% of the EPA limit, at the 95th percentile of samples — 60 µg/L |
| Fairview Union Water System | Coushatta | LA | 309.343 µg/L 516% of the EPA limit, at the 95th percentile of samples — 60 µg/L |
| Tatitlek Water System | Tatitlek | AK | 308 µg/L 513% of the EPA limit, at the 95th percentile of samples — 60 µg/L |
| Osage Co Rwd #20 (Hulah) | Bartlesville | OK | 295.6 µg/L 493% of the EPA limit, at the 95th percentile of samples — 60 µg/L |
| City of Strawn | — | TX | 292 µg/L 487% of the EPA limit, at the 95th percentile of samples — 60 µg/L |
| Oak Park | Okeechobee | FL | 278.117 µg/L 464% of the EPA limit, at the 95th percentile of samples — 60 µg/L |
| Rye Town of | — | CO | 274.169 µg/L 457% of the EPA limit, at the 95th percentile of samples — 60 µg/L |
| The Trails S/D | Chapel Hill | NC | 269 µg/L 448% of the EPA limit, at the 95th percentile of samples — 60 µg/L |
| Thorne Bay, City of | Thorne Bay | AK | 264 µg/L 440% of the EPA limit, at the 95th percentile of samples — 60 µg/L |
| Village of Sikes Water System | Sikes | LA | 260.4 µg/L 434% of the EPA limit, at the 95th percentile of samples — 60 µg/L |
| Asher Util Dev Auth | Asher | OK | 258.48 µg/L 431% of the EPA limit, at the 95th percentile of samples — 60 µg/L |
| Town of Oil City Water System | Oil City | LA | 248.11 µg/L 414% of the EPA limit, at the 95th percentile of samples — 60 µg/L |
| Orient Water Company | Republic | WA | 244.95 µg/L 408% of the EPA limit, at the 95th percentile of samples — 60 µg/L |
| City of Venus | — | TX | 241.15 µg/L 402% of the EPA limit, at the 95th percentile of samples — 60 µg/L |
Frequently asked questions about Total Haloacetic Acids (HAA5)
What is Total Haloacetic Acids (HAA5) in drinking water?
Haloacetic acids are chlorination by-products; long-term exposure raises cancer risk.
What is the EPA limit for Total Haloacetic Acids (HAA5)?
The EPA's Maximum Contaminant Level for Total Haloacetic Acids (HAA5) is 60 µg/L. A result above the limit means the supplier must act; the goal is the level at which no health effects are expected.
How common is Total Haloacetic Acids (HAA5) in US tap water?
Of the 34,024 water suppliers with results on file, 27,470 detected Total Haloacetic Acids (HAA5) — 80.7% of those tested.