Total trihalomethanes (TTHM) above the legal limit in the period starting January 2026.
Serves about 4,254 people (185 connections) with surface water from its own intake.
From EPA's record for VA2109510. PurityMap is independent of Louisa County Water Authority.
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9 health-based violations in the last 10 years, from EPA's SDWIS compliance database.
| Period | Contaminant | Measured | Legal limit | EPA status |
|---|---|---|---|---|
| Jan–Mar 2026 | Total trihalomethanes (TTHM) | 84 µg/L | 0.080 mg/L | Archived |
| Oct–Dec 2025 | Haloacetic acids (HAA5) | 62 µg/L | 0.060 mg/L | Resolved |
| Oct–Dec 2025 | Total trihalomethanes (TTHM) | 110 µg/L | 0.080 mg/L | Archived |
| Jul–Sep 2025 | Haloacetic acids (HAA5) | 66 µg/L | 0.060 mg/L | Resolved |
| Jul–Sep 2025 | Total trihalomethanes (TTHM) | 84 µg/L | 0.080 mg/L | Archived |
| Period | Contaminant | Measured | Legal limit | EPA status |
|---|---|---|---|---|
| Jul–Sep 2017 | Haloacetic acids (HAA5) | 0.062 mg/L | 0.060 mg/L | Resolved |
| Apr–Jun 2017 | Haloacetic acids (HAA5) | 92 µg/L | 0.060 mg/L | Resolved |
| Jan–Mar 2017 | Haloacetic acids (HAA5) | 0.099 mg/L | 0.060 mg/L | Resolved |
| Oct–Dec 2016 | Haloacetic acids (HAA5) | 0.098 mg/L | 0.060 mg/L | Resolved |
EPA required this system to test for 30 unregulated and emerging contaminants, from March 2024 to December 2024.
| Contaminant | Result | Limit | Status | Sampled | Source |
|---|---|---|---|---|---|
| 11-Chloroeicosafluoro-3-oxaundecane-1-sulfonic acid (11Cl-PF3OUdS) | < 5 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2024-03-19 to 2024-12-09 | UCMR5 Analytical Results: LOUISA COUNTY WATER AUTHORITY (VA2109510) |
| 1H, 1H, 2H, 2H-perfluorodecane sulfonic acid (8:2 FTS) | < 5 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2024-03-19 to 2024-12-09 | UCMR5 Analytical Results: LOUISA COUNTY WATER AUTHORITY (VA2109510) |
| 1H, 1H, 2H, 2H-perfluorohexane sulfonic acid (4:2 FTS) | < 3 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2024-03-19 to 2024-12-09 | UCMR5 Analytical Results: LOUISA COUNTY WATER AUTHORITY (VA2109510) |
| 1H, 1H, 2H, 2H-perfluorooctane sulfonic acid (6:2 FTS) | < 5 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2024-03-19 to 2024-12-09 | UCMR5 Analytical Results: LOUISA COUNTY WATER AUTHORITY (VA2109510) |
| 4,8-Dioxa-3H-perfluorononanoic acid (ADONA) | < 3 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2024-03-19 to 2024-12-09 | UCMR5 Analytical Results: LOUISA COUNTY WATER AUTHORITY (VA2109510) |
| 9-Chlorohexadecafluoro-3-oxanone-1-sulfonic acid (9Cl-PF3ONS) | < 2 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2024-03-19 to 2024-12-09 | UCMR5 Analytical Results: LOUISA COUNTY WATER AUTHORITY (VA2109510) |
| Hexafluoropropylene oxide dimer acid (HFPO-DA) (GenX chemicals) | < 5 ng/L | 10 ng/L federal MCL (2024) | Not detected above the reporting limit | 2024-03-19 to 2024-12-09 | UCMR5 Analytical Results: LOUISA COUNTY WATER AUTHORITY (VA2109510) |
| Lithium | < 9 µg/L | 10 µg/L EPA health reference level (screening, not a legal limit)Screening level, not a legal limit | Not detected above the reporting limit | 2024-03-19 to 2024-12-09 | UCMR5 Analytical Results: LOUISA COUNTY WATER AUTHORITY (VA2109510) |
| N-ethyl perfluorooctanesulfonamidoacetic acid (NEtFOSAA) | < 5 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2024-03-19 to 2024-12-09 | UCMR5 Analytical Results: LOUISA COUNTY WATER AUTHORITY (VA2109510) |
| N-methyl perfluorooctanesulfonamidoacetic acid (NMeFOSAA) | < 6 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2024-03-19 to 2024-12-09 | UCMR5 Analytical Results: LOUISA COUNTY WATER AUTHORITY (VA2109510) |
| Nonafluoro-3,6-dioxaheptanoic acid (NFDHA) | < 20 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2024-03-19 to 2024-12-09 | UCMR5 Analytical Results: LOUISA COUNTY WATER AUTHORITY (VA2109510) |
| Perfluoro (2-ethoxyethane) sulfonic acid (PFEESA) | < 3 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2024-03-19 to 2024-12-09 | UCMR5 Analytical Results: LOUISA COUNTY WATER AUTHORITY (VA2109510) |
| Perfluoro-3-methoxypropanoic acid (PFMPA) | < 4 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2024-03-19 to 2024-12-09 | UCMR5 Analytical Results: LOUISA COUNTY WATER AUTHORITY (VA2109510) |
| Perfluoro-4-methoxybutanoic acid (PFMBA) | < 3 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2024-03-19 to 2024-12-09 | UCMR5 Analytical Results: LOUISA COUNTY WATER AUTHORITY (VA2109510) |
| Perfluorobutanesulfonic acid (PFBS) | < 3 ng/L | 2,000 ng/L EPA health advisory (screening, not a legal limit)Screening level, not a legal limit | Not detected above the reporting limit | 2024-03-19 to 2024-12-09 | UCMR5 Analytical Results: LOUISA COUNTY WATER AUTHORITY (VA2109510) |
| Perfluorobutanoic acid (PFBA) | < 5 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2024-03-19 to 2024-12-09 | UCMR5 Analytical Results: LOUISA COUNTY WATER AUTHORITY (VA2109510) |
| Perfluorodecanoic acid (PFDA) | < 3 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2024-03-19 to 2024-12-09 | UCMR5 Analytical Results: LOUISA COUNTY WATER AUTHORITY (VA2109510) |
| Perfluorododecanoic acid (PFDoA) | < 3 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2024-03-19 to 2024-12-09 | UCMR5 Analytical Results: LOUISA COUNTY WATER AUTHORITY (VA2109510) |
| Perfluoroheptanesulfonic acid (PFHpS) | < 3 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2024-03-19 to 2024-12-09 | UCMR5 Analytical Results: LOUISA COUNTY WATER AUTHORITY (VA2109510) |
| Perfluoroheptanoic acid (PFHpA) | < 3 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2024-03-19 to 2024-12-09 | UCMR5 Analytical Results: LOUISA COUNTY WATER AUTHORITY (VA2109510) |
| Perfluorohexanesulfonic acid (PFHxS) | < 3 ng/L | 10 ng/L federal MCL (2024) | Not detected above the reporting limit | 2024-03-19 to 2024-12-09 | UCMR5 Analytical Results: LOUISA COUNTY WATER AUTHORITY (VA2109510) |
| Perfluorohexanoic acid (PFHxA) | < 3 ng/L | 400,000 ng/L Michigan EGLE state MCL (strictest US state) | Not detected above the reporting limit | 2024-03-19 to 2024-12-09 | UCMR5 Analytical Results: LOUISA COUNTY WATER AUTHORITY (VA2109510) |
| Perfluorononanoic acid (PFNA) | < 4 ng/L | 10 ng/L federal MCL (2024) | Not detected above the reporting limit | 2024-03-19 to 2024-12-09 | UCMR5 Analytical Results: LOUISA COUNTY WATER AUTHORITY (VA2109510) |
| Perfluorooctanesulfonic acid (PFOS) | < 4 ng/L | 4.0 ng/L federal MCL (2024) | Not detected above the reporting limit | 2024-03-19 to 2024-12-09 | UCMR5 Analytical Results: LOUISA COUNTY WATER AUTHORITY (VA2109510) |
| Perfluorooctanoic acid (PFOA) | < 4 ng/L | 4.0 ng/L federal MCL (2024) | Not detected above the reporting limit | 2024-03-19 to 2024-12-09 | UCMR5 Analytical Results: LOUISA COUNTY WATER AUTHORITY (VA2109510) |
| Perfluoropentanesulfonic acid (PFPeS) | < 4 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2024-03-19 to 2024-12-09 | UCMR5 Analytical Results: LOUISA COUNTY WATER AUTHORITY (VA2109510) |
| Perfluoropentanoic acid (PFPeA) | < 3 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2024-03-19 to 2024-12-09 | UCMR5 Analytical Results: LOUISA COUNTY WATER AUTHORITY (VA2109510) |
| Perfluorotetradecanoic acid (PFTA) | < 8 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2024-03-19 to 2024-12-09 | UCMR5 Analytical Results: LOUISA COUNTY WATER AUTHORITY (VA2109510) |
| Perfluorotridecanoic acid (PFTrDA) | < 7 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2024-03-19 to 2024-12-09 | UCMR5 Analytical Results: LOUISA COUNTY WATER AUTHORITY (VA2109510) |
| Perfluoroundecanoic acid (PFUnA) | < 2 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2024-03-19 to 2024-12-09 | UCMR5 Analytical Results: LOUISA COUNTY WATER AUTHORITY (VA2109510) |
Screening tells you if something is worth a closer look; a lab result is the number you can act on.
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Screening: quick check, not lab-grade
Safe Home (EnviroTestKits)
Lead, read as one of three ranges: 0–4, 5–15 or 15+ ppb
Turnaround: 5 minutes
What it can't tell you: It shows a lead range, not an exact level, and tests nothing else unless you pay extra for the optional lab test.
Lab-certified results
ETR Laboratories
50+ substances, including lead, copper, arsenic, nitrate, hardness and coliform bacteria
Environmental Testing and Research Laboratories (ETR Labs), Leominster, MA · ISO/IEC 17025:2017, ANAB certificate AT-2638 · 2–4 business days after the lab receives it
What it can't tell you: It does not test PFAS, and not every result on the panel falls under the lab's accredited scope.
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Follow this water →Louisa County Water Authority's phone number on EPA record is 540-967-1122. Its mailing address is 23 Loudin Lane, LOUISA, VA 23093.
According to EPA's record, Louisa County Water Authority uses surface water from its own intake.
EPA's record shows 9 health-based violations for Louisa County Water Authority in the 10 years to July 9, 2026. Total trihalomethanes (TTHM) were above the legal limit in the period starting January 2026. The record comes from EPA's SDWIS compliance database.
Lead was not detected at the 90th percentile of tap samples in Louisa County Water Authority's latest lead and copper round, which ended in December 2024. The federal action level is 15 µg/L.
PurityMap has no verified website for Louisa County Water Authority. Its phone number on EPA record is 540-967-1122. Its mailing address on EPA record is 23 Loudin Lane, LOUISA, VA 23093. Your water bill lists the ways to contact your supplier and pay. PurityMap does not take payments.