Is Washington, OK Tap Water Safe? Quality & Contaminants

What was found in Washington's water

The level at the city's main supplier, the highest level anywhere in the city, the EPA limit for each, and where every figure comes from.

Contaminant	Level vs EPA limit	Suppliers	Source
Nitrate	6180 µg/L 62% of the EPA limit 10000 µg/L Main supplier: WASHINGTON · 600 people · 2018	1/1	SYR4
Nitrate-Nitrite	5368 µg/L 54% of the EPA limit 10000 µg/L Main supplier: WASHINGTON · 600 people · 2019	1/1	SYR4
Barium	231.9 µg/L 12% of the EPA limit 2000 µg/L Main supplier: WASHINGTON · 600 people · 2017	1/1	SYR4
Copper	215.4 µg/L 17% of the EPA limit 1300 µg/L Main supplier: WASHINGTON · 600 people · 2019	1/1	SYR4
Combined Uranium	17.46 µg/L 58% of the EPA limit 30 µg/L Main supplier: WASHINGTON · 600 people · 2019	1/1	SYR4
Lead	13.3 µg/L 89% of the EPA limit 15 µg/L Main supplier: WASHINGTON · 600 people · 2019	1/1	SYR4
Gross Beta Particle Activity	9.29145 pCi/L No EPA limit set Main supplier: WASHINGTON · 600 people · 2019	1/1	SYR4
Gross Alpha, Excl. Radon And U	7.66 pCi/L 51% of the EPA limit 15 pCi/L Main supplier: WASHINGTON · 600 people · 2019	1/1	SYR4
TTHM	7 µg/L 8.8% of the EPA limit 80 µg/L Main supplier: WASHINGTON · 600 people · 2019	1/1	SYR4
Bromoform	3.5 µg/L No EPA limit set Main supplier: WASHINGTON · 600 people · 2019	1/1	SYR4
Arsenic	2.775 µg/L 28% of the EPA limit 10 µg/L Main supplier: WASHINGTON · 600 people · 2019	1/1	SYR4
Dibromochloromethane	2.4 µg/L No EPA limit set Main supplier: WASHINGTON · 600 people · 2019	1/1	SYR4
Bromodichloromethane	1.1 µg/L No EPA limit set Main supplier: WASHINGTON · 600 people · 2019	1/1	SYR4
Dibromoacetic Acid	1 µg/L No EPA limit set Main supplier: WASHINGTON · 600 people · 2019	1/1	SYR4
Combined Radium (-226 And -228)	0.8432 pCi/L 17% of the EPA limit 5 pCi/L Main supplier: WASHINGTON · 600 people · 2019	1/1	SYR4
Lead	0.0045 mg/L 30% of the EPA limit 0.0150 mg/L Main supplier: WASHINGTON · 600 people · 2025	1/1	LCR

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 the system's samples — over 100% is worth reading, but is not by itself a violation. Formal violations are listed separately. These are the utilities' own EPA-reported results, not a city-wide average. A detection means the lab measured the substance — it isn't the same as exceeding a legal limit. Hover a source tag to see the EPA program and years behind each figure.

Water suppliers serving Washington

Supplier	Population served
WASHINGTON	600

Frequently asked questions about Washington tap water

Is Washington tap water safe to drink?

EPA testing detected 16 contaminants in the water serving Washington. A detection isn't the same as a violation — most detected levels are within federal limits. Check the level and source for each contaminant above, and your utility's annual Consumer Confidence Report for the official compliance status.

How many water suppliers serve Washington?

1 public water supplier report drinking-water monitoring for Washington, Oklahoma to the EPA. Each is listed above with its population served.

What contaminants are in Washington's water?

The contaminants EPA monitoring detected in Washington include Nitrate, Nitrate-Nitrite, Barium, Copper, Combined Uranium. The full list, with the level at the main supplier and the data source, is in the table above.

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.