Disinfection byproducts · 2025
HAA5 in City of Poquoson, VA tap water
City of Poquoson, VA's 2025 report shows HAA5 detected, but the EPA has not set an enforceable federal limit for it.
The measurement
| Statistic | Value | Federal limit |
|---|---|---|
Maximum Max Conc | 21 | 0 MCLG |
Reported level System-wide | 21 ug/L | 0 ug/L MCLG |
Range System-wide | 5–32 | 0 MCLG |
Range Range of Individual Test Results Low | 5–32 ug/L | 0 ug/L MCLG |
Highest single sample Max Conc | 7.8 | 0 MCLG |
Range System-wide | 0–7.8 | 0 MCLG |
Maximum Max Detected Level | 7.8 ug/L | 60 ug/L MCL |
Range System-wide | 0–7.8 ug/L | 60 ug/L MCL |
Verbatim from City of Poquoson, VA's 2025 Consumer Confidence Report — source document ↗
About HAA5
Haloacetic acids — a group of five disinfection byproducts formed when disinfectants react with organic matter.
Long-term exposure above the federal limit is associated with an increased cancer risk.
How City of Poquoson, VA compares
5 of the 377 systems measuring HAA5 on The Water Map have it at or above the federal limit:
Nearby systems also reporting HAA5:
People also ask
+Is there HAA5 in City of Poquoson, VA tap water?
Yes — City of Poquoson, VA's 2025 Consumer Confidence Report lists HAA5 at 5–32. City of Poquoson, VA's 2025 report shows HAA5 detected, but the EPA has not set an enforceable federal limit for it.
+What's the federal limit for HAA5 in drinking water?
The federal MCLG for HAA5 is 0 . The EPA enforces this against the regulated reporting statistic (running annual average or 90th percentile), not a single-sample spike.
+What is HAA5?
Haloacetic acids — a group of five disinfection byproducts formed when disinfectants react with organic matter. Long-term exposure above the federal limit is associated with an increased cancer risk.
+Which other U.S. cities have HAA5 over the federal limit?
5 of the 377 systems on The Water Map measuring HAA5 report it at or above the federal limit. Examples include Albuquerque, NM, Columbus, OH, Hollywood, FL.
+Where does this HAA5 measurement come from?
This page reproduces the HAA5 entry from the 2025 Consumer Confidence Report published by the City of Poquoson, VA water utility — the annual drinking-water report every U.S. utility is required by federal law to publish. The original source document is archived at /water/va/poquoson/2025/source.