Prince William County Water Quality: 2 Cities Ranked by the Records
Prince William County, Virginia: 2 city reports built from EPA and utility records. A county has many suppliers; each city shows the system that serves it.
Highest result for each contaminant
One row per contaminant: the highest result any system in the county reported, against its limit. Open a row for the systems behind it.
Perfluorooctanoic acid (PFOA)Detected in 1 system of 2 tested4.0 ng/L federal MCL (2024) · US EPAHighest7.1 ng/L
- DALE CITY7.1 ng/LSample date: 2023-09-04 to 2024-06-09
- MANASSAS, CITY OFNot detected · below 4.0 ng/L lab reporting limitSample date: 2023-06-06 to 2024-03-11
Perfluorooctanesulfonic acid (PFOS)Detected in 1 system of 2 tested4.0 ng/L federal MCL (2024) · US EPAHighest5.7 ng/L
- DALE CITY5.7 ng/LSample date: 2023-09-04 to 2024-06-09
- MANASSAS, CITY OFNot detected · below 4.0 ng/L lab reporting limitSample date: 2023-06-06 to 2024-03-11
Lead (90th percentile)Detected in 1 system of 2 tested15 µg/L federal action level · US EPAHighest0.47 µg/L
- MANASSAS, CITY OF0.47 µg/LMonitoring period: 2022–2024
- DALE CITYNot detectedMonitoring period: 2023–2025
Perfluorobutanesulfonic acid (PFBS)Detected in 1 system of 2 tested2,000 ng/L EPA health advisory (screening, not a legal limit) · US EPAHighest8.5 ng/L
- DALE CITY8.5 ng/LSample date: 2023-09-04 to 2024-06-09
- MANASSAS, CITY OFNot detected · below 3.0 ng/L lab reporting limitSample date: 2023-06-06 to 2024-03-11
Perfluorohexanoic acid (PFHxA)Detected in 2 systems400,000 ng/L Michigan EGLE state MCL (strictest US state) · Michigan EGLEHighest18 ng/L
- DALE CITY18 ng/LSample date: 2023-09-04 to 2024-06-09
- MANASSAS, CITY OF3.8 ng/LSample date: 2023-06-06 to 2024-03-11
Perfluorobutanoic acid (PFBA)Detected in 2 systemsNo federal or state limit; shown for transparencyHighest23.3 ng/L
- MANASSAS, CITY OF23.3 ng/LSample date: 2023-06-06 to 2024-03-11
- DALE CITY18.8 ng/LSample date: 2023-09-04 to 2024-06-09
Perfluoroheptanoic acid (PFHpA)Detected in 1 system of 2 testedNo federal or state limit; shown for transparencyHighest6.1 ng/L
- DALE CITY6.1 ng/LSample date: 2023-09-04 to 2024-06-09
- MANASSAS, CITY OFNot detected · below 3.0 ng/L lab reporting limitSample date: 2023-06-06 to 2024-03-11
Perfluoropentanoic acid (PFPeA)Detected in 2 systemsNo federal or state limit; shown for transparencyHighest21.9 ng/L
- DALE CITY21.9 ng/LSample date: 2023-09-04 to 2024-06-09
- MANASSAS, CITY OF4.1 ng/LSample date: 2023-06-06 to 2024-03-11
23 substances tested, none detected in any systemShow
Tested in these 2 systems: DALE CITY, MANASSAS, CITY OF
- 11-Chloroeicosafluoro-3-oxaundecane-1-sulfonic acid (11Cl-PF3OUdS)
- 1H, 1H, 2H, 2H-perfluorodecane sulfonic acid (8:2 FTS)
- 1H, 1H, 2H, 2H-perfluorohexane sulfonic acid (4:2 FTS)
- 1H, 1H, 2H, 2H-perfluorooctane sulfonic acid (6:2 FTS)
- 4,8-Dioxa-3H-perfluorononanoic acid (ADONA)
- 9-Chlorohexadecafluoro-3-oxanone-1-sulfonic acid (9Cl-PF3ONS)
- Hexafluoropropylene oxide dimer acid (HFPO-DA) (GenX chemicals)
- Lithium
- N-ethyl perfluorooctanesulfonamidoacetic acid (NEtFOSAA)
- N-methyl perfluorooctanesulfonamidoacetic acid (NMeFOSAA)
- Nonafluoro-3,6-dioxaheptanoic acid (NFDHA)
- Perfluoro (2-ethoxyethane) sulfonic acid (PFEESA)
- Perfluoro-3-methoxypropanoic acid (PFMPA)
- Perfluoro-4-methoxybutanoic acid (PFMBA)
- Perfluorodecanoic acid (PFDA)
- Perfluorododecanoic acid (PFDoA)
- Perfluoroheptanesulfonic acid (PFHpS)
- Perfluorohexanesulfonic acid (PFHxS)
- Perfluorononanoic acid (PFNA)
- Perfluoropentanesulfonic acid (PFPeS)
- Perfluorotetradecanoic acid (PFTA)
- Perfluorotridecanoic acid (PFTrDA)
- Perfluoroundecanoic acid (PFUnA)
Cities ranked by the records
Ranked by the Purity Score of each city's main water system, highest first. Scores belong to water systems; there is no county score. The score is computed only from contaminants measured in the published EPA record, so this ranks the record, not which city's water is safest. How the score works.
0of 2 cities above the 15 µg/L action level
Based on each system's 90th-percentile result. Lead from household plumbing isn't in this record.
Lead in VirginiaLargest water systems
Frequently asked
How does Prince William County tap water compare across cities?
PurityMap ranks 2 cities in Prince William County by the Purity Score of each city's main water system, computed only from contaminants measured in the published EPA record. Scores belong to water systems, not to cities. The highest published score is Manassas's main water system: MANASSAS, CITY OF · PWSID VA6685100 · Purity Score 100 (Excellent) · Confidence: moderate · Assessed at the water-system level. The ranking compares the records, not which city's water is safest, and your own tap can differ with household plumbing.
How many Prince William County cities had a PFAS sample above a 2024 EPA limit?
1 of 2 Prince William County city reports had a PFAS sample above a 2024 EPA limit in EPA's UCMR 5 testing, including Dale City (PFOA 7.1 ng/L). That limit is judged on a yearly average, and water systems have until 2029 to meet it, so a single sample is not a violation. PFAS were detected at any level in 2.
Is there lead in Prince William County tap water?
Utilities report lead as a 90th-percentile result from home taps. 1 of 2 Prince William County cities reported a value above zero, and none was above the 15 µg/L federal action level. Lead usually comes from a building's own pipes and fixtures, so only a test at your tap tells you what you drink.
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