- EPA's UCMR 5 testing looked for 30 contaminants here and found 6.
- Lithium: found in 5 of 11 samples, average 12.7 µg/L, highest 32 µg/L (EPA UCMR 5 testing, Jun 2023–Mar 2024)
- PFHxS (a PFAS): found in 5 of 10 samples, average 4.3 ppt, highest 12 ppt (EPA UCMR 5 testing, Jun 2023–Jun 2024)
- PFOS (a PFAS): found in 5 of 10 samples, average 3.5 ppt, highest 12 ppt (EPA UCMR 5 testing, Jun 2023–Jun 2024)
- PFBS (a PFAS): found in 5 of 10 samples, average 2.8 ppt, highest 10 ppt (EPA UCMR 5 testing, Jun 2023–Jun 2024)
- PFPeA (a PFAS): found in 1 of 11 samples, average 0.40 ppt, highest 4.2 ppt (EPA UCMR 5 testing, Jun 2023–Jun 2024)
- PFHxA (a PFAS): found in 1 of 11 samples, average 0.40 ppt, highest 3.9 ppt (EPA UCMR 5 testing, Jun 2023–Jun 2024)
- Lead, 90th percentile: 2 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, 2024–Dec 31, 2026). 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 Hermiston tap water? What EPA records show
EPA OR4100372 · serves Umatilla County, OR · about 20,000 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
Hermiston, City of (EPA OR4100372)
ScoreYourWater.com gives no verdict on your tap water; it shows what the public records say, as of October 14, 2026. For Hermiston's main utility, Hermiston, City of: We found no health-based violations in EPA's records for this system (OR4100372) since July 1, 2021, as of October 14, 2026. EPA's UCMR 5 testing looked for 30 contaminants here and found 6.
What EPA records show for Hermiston, City of, as of October 14, 2026
We found no health-based violations in EPA's records for this system (OR4100372) since July 1, 2021, as of October 14, 2026.
Source: EPA ECHO record for Hermiston, City of (SDWIS). Data as of October 14, 2026.
Lead, 90th percentile: 2 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, 2024–Dec 31, 2026). 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 6.
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 Hermiston, City of use chloramine?
We didn't find chloramine in Hermiston, City of's EPA treatment records. That's not a complete list; your utility's annual water quality report says which disinfectant it uses.