ZIP Code 78552
High RiskPFAS above EPA limits detected
2 compounds exceed EPA Maximum Contaminant Levels in water serving this ZIP code. Standard pitcher filters like Brita do not remove PFAS. See filter recommendations below.
19
PFAS Detected
2
Above EPA Limits
3
Water Systems
140%
Highest % of MCL
Compounds Exceeding EPA Limits
PFOS Exceeds EPA limit
0 ppt MCL: 4 ppt 140% of limit
Detected: 5.60 ppt
PFOA Exceeds EPA limit
0 ppt MCL: 4 ppt 135% of limit
Detected: 5.40 ppt
HARLINGEN WATER WORKS SYSTEM
TX0310002 Low LevelWater Type
Surface Water
PFAS Detected
4
Above MCL
0
State
Texas
Data Period
2023–2025
PFAS Test Results
| Compound | Detected | vs. EPA Limit | EPA Limit | Status |
|---|---|---|---|---|
lithium | 46900.00ppt | No federal limit | — | Unregulated |
PFBA Perfluorobutanoic acid | 8.80ppt | No federal limit | — | Unregulated |
PFPeA Perfluoropentanoic acid | 3.00ppt | No federal limit | — | Unregulated |
PFHxA Perfluorohexanoic acid | 3.00ppt | No federal limit | — | Unregulated |
CITY OF PRIMERA
TX0310094 ModerateWater Type
Surface Water
PFAS Detected
6
Above MCL
0
State
Texas
Data Period
2023–2025
PFAS Test Results
| Compound | Detected | vs. EPA Limit | EPA Limit | Status |
|---|---|---|---|---|
PFHxS Perfluorohexane sulfonic acid | 3.40ppt | 34% of limit
| 10 ppt | Below limit |
lithium | 62100.00ppt | No federal limit | — | Unregulated |
PFBA Perfluorobutanoic acid | 13.60ppt | No federal limit | — | Unregulated |
PFBS Perfluorobutane sulfonic acid | 10.40ppt | No federal limit | — | Unregulated |
PFHxA Perfluorohexanoic acid | 8.80ppt | No federal limit | — | Unregulated |
PFPeA Perfluoropentanoic acid | 8.50ppt | No federal limit | — | Unregulated |
EAST RIO HONDO WSC
TX0310096 High RiskWater Type
Surface Water
PFAS Detected
9
Above MCL
2
State
Texas
Data Period
2023–2025
PFAS Test Results
| Compound | Detected | vs. EPA Limit | EPA Limit | Status |
|---|---|---|---|---|
PFOS Perfluorooctane sulfonic acid | 5.60ppt | 140% of limit
| 4 ppt | ⚠ Exceeds MCL |
PFOA Perfluorooctanoic acid | 5.40ppt | 135% of limit
| 4 ppt | ⚠ Exceeds MCL |
PFHxS Perfluorohexane sulfonic acid | 4.50ppt | 45% of limit
| 10 ppt | Below limit |
lithium | 56500.00ppt | No federal limit | — | Unregulated |
PFBA Perfluorobutanoic acid | 14.80ppt | No federal limit | — | Unregulated |
PFPeA Perfluoropentanoic acid | 11.70ppt | No federal limit | — | Unregulated |
PFHxA Perfluorohexanoic acid | 11.20ppt | No federal limit | — | Unregulated |
PFHpA Perfluoroheptanoic acid | 4.00ppt | No federal limit | — | Unregulated |
Show 1 more compound detected at low levels
| PFBSPerfluorobutane sulfonic acid | 3.50 ppt | No federal limit |
Note: ZIP code 78552 is served by 3 separate water utilities.
Results above show data for each system independently.
Data source: EPA Unregulated Contaminant Monitoring Rule, 5th cycle (UCMR 5) — January 2026 release.
UCMR 5 tested ~10,000 public water systems serving more than 25 people between 2023-2025 for 29 PFAS compounds.
Detection values represent the highest single-sample result measured at entry points to the distribution system.