What was found in Arlington'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 | 1633 µg/L 16% of the EPA limit 10000 µg/L Main supplier: ARLINGTON CITY OF · 29,508 people · 2019
Highest in the city: 9043 µg/L — GAYS WATER DISTRICT ASSOCIATION · 81 people · 2019 | 21/35 | SYR4 |
| Nitrate-Nitrite | 1621 µg/L 16% of the EPA limit 10000 µg/L Main supplier: ARLINGTON CITY OF · 29,508 people · 2019
Highest in the city: 6225 µg/L — ROSELAND COMMUNITY CLUB ASSOCIATION · 210 people · 2019 | 18/35 | SYR4 |
| Fluoride | 150 µg/L 3.8% of the EPA limit 4000 µg/L Highest in the city: KYAK RIDGE WATER SYSTEM · 66 people · 2016 | 7/35 | SYR4 |
| TTHM | 36.04 µg/L 45% of the EPA limit 80 µg/L Main supplier: ARLINGTON CITY OF · 29,508 people · 2019
Highest in the city: 57.725 µg/L — MEADOW LAKE WATER ASSOCIATION · 171 people · 2019 | 21/35 | SYR4 |
| Chloroform | 31.78 µg/L No EPA limit set Main supplier: ARLINGTON CITY OF · 29,508 people · 2019
Highest in the city: 55.46 µg/L — MEADOW LAKE WATER ASSOCIATION · 171 people · 2019 | 21/35 | SYR4 |
| Barium | 15.35 µg/L 0.8% of the EPA limit 2000 µg/L Main supplier: ARLINGTON CITY OF · 29,508 people · 2019
Highest in the city: 52 µg/L — NEW START LANDOWNERS ASSOCIATION · 90 people · 2019 | 17/35 | SYR4 |
| Copper | 48 µg/L 3.7% of the EPA limit 1300 µg/L Main supplier: ARLINGTON CITY OF · 29,508 people · 2019 | 7/35 | SYR4 |
| Total Haloacetic Acids (HAA5) | 26.975 µg/L 45% of the EPA limit 60 µg/L Main supplier: ARLINGTON CITY OF · 29,508 people · 2019
Highest in the city: 38.015 µg/L — PILCHUCK RIVIERA #1 · 90 people · 2019 | 18/35 | SYR4 |
| Trichloroacetic Acid | 15.075 µg/L No EPA limit set Main supplier: ARLINGTON CITY OF · 29,508 people · 2019
Highest in the city: 23.82 µg/L — PILCHUCK RIVIERA #1 · 90 people · 2019 | 17/35 | SYR4 |
| Dibromochloromethane | 1.945 µg/L No EPA limit set Main supplier: ARLINGTON CITY OF · 29,508 people · 2019
Highest in the city: 16.92 µg/L — PRIEST POINT BEACH WATER INC · 624 people · 2018 | 9/35 | SYR4 |
| Dichloroacetic Acid | 12.16 µg/L No EPA limit set Main supplier: ARLINGTON CITY OF · 29,508 people · 2019
Highest in the city: 16.655 µg/L — SCHLUTER WATER ASSOCIATION · 224 people · 2019 | 16/35 | SYR4 |
| Bromoform | 0.6000 µg/L No EPA limit set Main supplier: ARLINGTON CITY OF · 29,508 people · 2019
Highest in the city: 16.34 µg/L — PRIEST POINT BEACH WATER INC · 624 people · 2018 | 6/35 | SYR4 |
| Bromodichloromethane | 4.1 µg/L No EPA limit set Main supplier: ARLINGTON CITY OF · 29,508 people · 2019
Highest in the city: 16.325 µg/L — EAGLE RIDGE · 250 people · 2018 | 19/35 | SYR4 |
| Dibromoacetic Acid | 9.605 µg/L No EPA limit set Highest in the city: PRIEST POINT BEACH WATER INC · 624 people · 2017 | 6/35 | SYR4 |
| Arsenic | 1 µg/L 10% of the EPA limit 10 µg/L Main supplier: ARLINGTON CITY OF · 29,508 people · 2019
Highest in the city: 8 µg/L — SUNNY SHORES COMMUNITY CLUB · 60 people · 2019 | 15/35 | SYR4 |
| Gross Beta Particle Activity | 7.941 pCi/L No EPA limit set Highest in the city: MERIDIAN WATER SYSTEM · 81 people · 2015 | 4/35 | SYR4 |
| Monochloroacetic Acid | 2.525 µg/L No EPA limit set Main supplier: ARLINGTON CITY OF · 29,508 people · 2019
Highest in the city: 6.3515 µg/L — NORTH RIDGE WATER CORP · 135 people · 2019 | 10/35 | SYR4 |
| Chromium | 5 µg/L 5% of the EPA limit 100 µg/L Main supplier: ARLINGTON CITY OF · 29,508 people · 2019 | 11/35 | SYR4 |
| Monobromoacetic Acid | 5 µg/L No EPA limit set Highest in the city: PILCHUCK RIVIERA #1 · 90 people · 2019 | 3/35 | SYR4 |
| Lead | 1 µg/L 6.7% of the EPA limit 15 µg/L Highest in the city: PANTHER LAKE COMMUNITY WATER SYSTEM · 47 people · 2019 | 1/35 | SYR4 |
| Toluene | 0.6000 µg/L 0.1% of the EPA limit 1000 µg/L Highest in the city: ARLINGTON EAST MUTUAL WATER ASSN. · 100 people · 2016 | 1/35 | SYR4 |
| Xylenes, Total | 0.4000 µg/L 0% of the EPA limit 10000 µg/L Highest in the city: ARLINGTON EAST MUTUAL WATER ASSN. · 100 people · 2016 | 1/35 | SYR4 |
| Tetrachloroethylene | 0.3000 µg/L 6% of the EPA limit 5 µg/L Highest in the city: ARLINGTON EAST MUTUAL WATER ASSN. · 100 people · 2016 | 1/35 | SYR4 |
| Lead | 0.0 mg/L 0% of the EPA limit 0.0150 mg/L Main supplier: ARLINGTON CITY OF · 29,508 people · 2024
Highest in the city: 0.0091 mg/L — GAYS WATER DISTRICT ASSOCIATION · 81 people · 2023 | 28/35 | LCR |
| PFHXS | 0.0049 µg/L No EPA limit set Main supplier: ARLINGTON CITY OF · 29,508 people · 2023 | 1/35 | UCMR-5 |
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 Arlington
Frequently asked questions about Arlington tap water
Is Arlington tap water safe to drink?
EPA testing detected 25 contaminants in the water serving Arlington. 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 Arlington?
35 public water suppliers report drinking-water monitoring for Arlington, Washington to the EPA. Each is listed above with its population served.
What contaminants are in Arlington's water?
The contaminants EPA monitoring detected in Arlington include Nitrate, Nitrate-Nitrite, Fluoride, TTHM, Chloroform. 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.