- EPA's UCMR 5 testing looked for 30 contaminants here and found 4.
- Lithium: found in 8 of 8 samples, average 40.5 µg/L, highest 46.9 µg/L (EPA UCMR 5 testing, Aug 2023–May 2024)
- PFBA (a PFAS): found in 5 of 8 samples, average 4.9 ppt, highest 8.8 ppt (EPA UCMR 5 testing, Aug 2023–Jun 2024)
- PFHxA (a PFAS): found in 1 of 8 samples, average 0.40 ppt, highest 3 ppt (EPA UCMR 5 testing, Aug 2023–Jun 2024)
- PFPeA (a PFAS): found in 1 of 8 samples, average 0.40 ppt, highest 3 ppt (EPA UCMR 5 testing, Aug 2023–Jun 2024)
- Lead, 90th percentile: 0 ppb at the latest result in EPA records for a monitoring period that ran on or after July 1, 2021, at or below EPA's 15 ppb action level (EPA SDWIS, monitoring period Jan 1, 2022–Dec 31, 2024). The 90th percentile is a system-wide measure from homes sampled under EPA's lead rule; it isn't a result for your home.
Public EPA test results
Can you drink Harlingen tap water? What EPA records show
EPA TX0310002 · serves Cameron County, TX · about 85,900 people (EPA SDWIS)
This report shows EPA's federal records for this water system: UCMR 5 testing, lead testing and violations. It isn't a test of the water at your tap, and it has no Water Score.
Public EPA test results
Harlingen Water Works System (EPA TX0310002)
EPA data as of October 14, 2026. For Harlingen's main utility, Harlingen Water Works System: We found no health-based violations in EPA's records for this system (TX0310002) since July 1, 2021, as of October 14, 2026. PFOA and PFOS were not detected at or above EPA's reporting level in EPA's UCMR 5 testing.
What EPA records show for Harlingen Water Works System, as of October 14, 2026
We found no health-based violations in EPA's records for this system (TX0310002) since July 1, 2021, as of October 14, 2026.
Source: EPA ECHO record for Harlingen Water Works System (SDWIS). Data as of October 14, 2026.
Lead, 90th percentile: 0 ppb at the latest result in EPA records for a monitoring period that ran on or after July 1, 2021, at or below EPA's 15 ppb action level (EPA SDWIS, monitoring period Jan 1, 2022–Dec 31, 2024). The 90th percentile is a system-wide measure from homes sampled under EPA's lead rule; it isn't a result for your home.
EPA's UCMR 5 testing looked for 30 contaminants here and found 4.
PFOA and PFOS were not detected at or above EPA's reporting level in EPA's UCMR 5 testing.
Source: EPA records (SDWIS, UCMR 5). SDWIS: data as of Oct 14, 2026. EPA UCMR 5 data, samples through June 2026.
Your water bill names your utility.
Does Harlingen Water Works System use chloramine?
EPA treatment records (state-reported) list chloramines for Harlingen Water Works System. EPA record