Tap WaterIndex

← Oregon

Tap water quality report

Ontario, City of

EPA monitoring tested this supplier for 103 contaminants and detected 14. A detection doesn't automatically mean the water is unsafe — the level and EPA source for each is below.

103
contaminants tested
14
detected
14,465
people served
1
health-based violations
Oregon rankingsLead in OregonPFAS in Oregon
Water source
Surface water
Ownership
Local government
Counties served
Malheur

Compliance record

Formal violations the EPA has on file for this supplier. A health-based violation means a contaminant limit or a required treatment was breached; the rest are monitoring or reporting failures — still violations, but not a measured health risk.

1
health-based violations
145
violations on file
0
still open
ViolationTypeStatusPeriod
TT Health-based Resolved 2002-03-01 → 2002-03-31
MR Monitoring Resolved 2023-03-01 → 2023-03-31
MR Monitoring Resolved 2023-03-01 → 2023-03-31
MR Monitoring Resolved 2023-03-01 → 2023-03-31
MR Monitoring Resolved 2023-03-01 → 2023-03-31
MR Monitoring Resolved 2023-03-01 → 2023-03-31
MR Monitoring Resolved 2023-03-01 → 2023-03-31
MON Monitoring Resolved 2023-01-01 → 2023-01-31
MR Monitoring Resolved 2015-07-01 → 2015-09-30
MR Monitoring Resolved 2015-07-01 → 2015-09-30

Other contaminants detected

Each bar shows the measured level as a share of the EPA limit: green is well under, amber is close to it, red is over. For lead and copper the limit applies to exactly the 90th-percentile figure shown, so red there means a real exceedance. For everything else the limit applies to a running annual average while the figure is the 95th percentile of this system's samples — over 100% is worth reading, but is not by itself a violation. Where a single sample came in higher than that percentile, it is noted under the bar. Formal violations are listed separately.
ContaminantLevel vs EPA limitDetection rateSourcePeriod
TTHM
78.085 µg/L 98%
of the EPA limit 80 µg/L
worst single sample: 83.4 µg/L
124/124 SYR4 2012–2019
Total Haloacetic Acids (HAA5)
42.025 µg/L 70%
of the EPA limit 60 µg/L
worst single sample: 47.3 µg/L
122/124 SYR4 2012–2019
Copper
306.25 µg/L 24%
of the EPA limit 1300 µg/L
worst single sample: 367 µg/L
76/152 SYR4 2014–2018
Lead
0.0021 mg/L 14%
of the EPA limit 0.0150 mg/L
 26/26 LCR 2024
Lead
6.705 µg/L 45%
of the EPA limit 15 µg/L
worst single sample: 7.41 µg/L
23/152 SYR4 2014–2018
Nitrate
2020 µg/L 20%
of the EPA limit 10000 µg/L
 18/20 SYR4 2012–2019
Arsenic
5.046 µg/L 50%
of the EPA limit 10 µg/L
worst single sample: 5.14 µg/L
5/11 SYR4 2012–2019
Combined Uranium
2.8625 µg/L 9.5%
of the EPA limit 30 µg/L
worst single sample: 2.9 µg/L
4/4 SYR4 2013–2019
Lithium
38.4 µg/L
No EPA limit set
 4/4 UCMR-5 2025
Barium
60.63 µg/L 3%
of the EPA limit 2000 µg/L
worst single sample: 61.1 µg/L
3/3 SYR4 2014–2019
Fluoride
705.3 µg/L 18%
of the EPA limit 4000 µg/L
worst single sample: 718 µg/L
3/3 SYR4 2014–2019
Chromium
1.285 µg/L 1.3%
of the EPA limit 100 µg/L
worst single sample: 1.29 µg/L
2/3 SYR4 2014–2019
Nitrate-Nitrite
1147 µg/L 11%
of the EPA limit 10000 µg/L
worst single sample: 1150 µg/L
2/3 SYR4 2014–2019
Gross Alpha, Excl. Radon And U
3.13 pCi/L 21%
of the EPA limit 15 pCi/L
 1/4 SYR4 2014–2019
89 contaminants tested, none detected
1,1,1-Trichloroethane1,1,2-Trichloroethane1,1-Dichloroethylene1,2,4-Trichlorobenzene1,2-DIBROMO-3-CHLOROPROPANE1,2-Dichloroethane1,2-Dichloropropane11Cl-PF3OUdS2,4,5-TP2,4-D4:2 Fts6:2 Fts8:2 Fts9Cl-PF3ONSAdonaAntimony, TotalAsbestosAtrazineBhc-GammaBenzeneBenzo(A)PyreneBeryllium, TotalChlorobenzeneCyanideCadmiumCarbofuranCarbon TetrachlorideChlordaneCombined Radium (-226 And -228)DichloromethaneDalaponDi(2-ethylhexyl) AdipateDi(2-ethylhexyl) PhthalateDinosebDiquatEthylene DibromideEndothallEndrinEthylbenzeneGlyphosateHexachlorobenzeneHfpo-DaHeptachlorHeptachlor EpoxideHexachlorocyclopentadieneLassoMercuryMethoxychlorNetfosaaNfdhaNmefosaaNitriteOxamylPfbaPFBSPfdaPfdoaPfeesaPfhpaPfhpsPfhxaPFHXSPfmbaPfmpaPFNAPFOAPFOSPfpeaPfpesPftaPftrdaPfunaPentachlorophenolPicloramSeleniumSimazineStyreneTetrachloroethyleneThallium, TotalTolueneTotal Polychlorinated Biphenyls (PCB)ToxapheneTrichloroethyleneVinyl ChlorideXylenes, Totalcis-1,2-DichloroethyleneO-DichlorobenzeneP-Dichlorobenzenetrans-1,2-Dichloroethylene

Utility contact

Contact
ONTARIO, CITY OF
Phone
541-889-8011
Email
[email protected]

Frequently asked questions about Ontario, City of

Is Ontario, City of tap water safe to drink?

EPA monitoring detected 14 contaminants in Ontario, City of's water. A detection isn't the same as a violation — most levels are within federal limits. See each level and source above, and the utility's annual Consumer Confidence Report for its official compliance status.

What contaminants were detected in Ontario, City of's water?

EPA monitoring detected TTHM, Total Haloacetic Acids (HAA5), Copper, Lead, Lead, and others. The full list with the level and data source for each is above.

How many people does Ontario, City of serve?

Ontario, City of reports serving 14,465 people in Oregon, per its EPA record.

Has Ontario, City of had any water quality violations?

The EPA has 145 violations on file for Ontario, City of, of which 1 is health-based (a contaminant limit or required treatment was breached) and 0 remain open. The rest are monitoring or reporting failures.

Where does this data come from?

Every figure is official EPA drinking-water monitoring — the Lead & Copper Rule, the UCMR-5 nationwide testing program, and the EPA Six-Year Review — not our own testing. Each number is labelled with its source and period.