What was found in ZIP 98178
The level at this ZIP's main supplier, the highest level anywhere in it, the EPA limit for each, and where the figure comes from.
| Contaminant | Level vs EPA limit | Suppliers | Source |
|---|---|---|---|
| Nitrate | 1054 µg/L 11% of the EPA limit 10000 µg/L Main supplier: SEATTLE PUBLIC UTILITIES · 1,161,961 people · 2019
Highest in the ZIP: 2780 µg/L — SKYWAY WATER & SEWER · 12,036 people · 2019 | 3/4 | SYR4 |
| Nitrate-Nitrite | 2090 µg/L 21% of the EPA limit 10000 µg/L Highest in the ZIP: RENTON CITY OF · 108,091 people · 2019 | 2/4 | SYR4 |
| Fluoride | 795 µg/L 20% of the EPA limit 4000 µg/L Main supplier: SEATTLE PUBLIC UTILITIES · 1,161,961 people · 2012 | 3/4 | SYR4 |
| Total Haloacetic Acids (HAA5) | 50.606 µg/L 84% of the EPA limit 60 µg/L Main supplier: SEATTLE PUBLIC UTILITIES · 1,161,961 people · 2019
Highest in the ZIP: 59.865 µg/L — SKYWAY WATER & SEWER · 12,036 people · 2019 | 4/4 | SYR4 |
| TTHM | 49.723 µg/L 62% of the EPA limit 80 µg/L Main supplier: SEATTLE PUBLIC UTILITIES · 1,161,961 people · 2019 | 4/4 | SYR4 |
| Chloroform | 45.3 µg/L No EPA limit set Main supplier: SEATTLE PUBLIC UTILITIES · 1,161,961 people · 2019 | 4/4 | SYR4 |
| Trichloroacetic Acid | 29.75 µg/L No EPA limit set Main supplier: SEATTLE PUBLIC UTILITIES · 1,161,961 people · 2019
Highest in the ZIP: 34 µg/L — SKYWAY WATER & SEWER · 12,036 people · 2019 | 4/4 | SYR4 |
| Dichloroacetic Acid | 23.5 µg/L No EPA limit set Main supplier: SEATTLE PUBLIC UTILITIES · 1,161,961 people · 2019
Highest in the ZIP: 26.38 µg/L — SKYWAY WATER & SEWER · 12,036 people · 2019 | 4/4 | SYR4 |
| Copper | 4.35 µg/L 0.3% of the EPA limit 1300 µg/L Main supplier: SEATTLE PUBLIC UTILITIES · 1,161,961 people · 2012
Highest in the ZIP: 20 µg/L — RENTON CITY OF · 108,091 people · 2019 | 2/4 | SYR4 |
| Arsenic | 8.08 µg/L 81% of the EPA limit 10 µg/L Main supplier: SEATTLE PUBLIC UTILITIES · 1,161,961 people · 2012 | 2/4 | SYR4 |
| Barium | 3.48 µg/L 0.2% of the EPA limit 2000 µg/L Main supplier: SEATTLE PUBLIC UTILITIES · 1,161,961 people · 2012
Highest in the ZIP: 7 µg/L — SKYWAY WATER & SEWER · 12,036 people · 2019 | 2/4 | SYR4 |
| Bromodichloromethane | 2.7465 µg/L No EPA limit set Main supplier: SEATTLE PUBLIC UTILITIES · 1,161,961 people · 2019
Highest in the ZIP: 6.799 µg/L — SKYWAY WATER & SEWER · 12,036 people · 2019 | 4/4 | SYR4 |
| Dibromochloromethane | 1.922 µg/L No EPA limit set Main supplier: SEATTLE PUBLIC UTILITIES · 1,161,961 people · 2019
Highest in the ZIP: 4.8 µg/L — TUKWILA WATER DEPARTMENT · 36,298 people · 2019 | 4/4 | SYR4 |
| Monochloroacetic Acid | 3.515 µg/L No EPA limit set Main supplier: SEATTLE PUBLIC UTILITIES · 1,161,961 people · 2019
Highest in the ZIP: 4.725 µg/L — SKYWAY WATER & SEWER · 12,036 people · 2019 | 3/4 | SYR4 |
| Gross Beta Particle Activity | 2.36 pCi/L No EPA limit set Highest in the ZIP: SKYWAY WATER & SEWER · 12,036 people · 2018 | 1/4 | SYR4 |
| Nitrite | 2 µg/L 0.2% of the EPA limit 1000 µg/L Main supplier: SEATTLE PUBLIC UTILITIES · 1,161,961 people · 2019 | 1/4 | SYR4 |
| Monobromoacetic Acid | 1.69 µg/L No EPA limit set Highest in the ZIP: TUKWILA WATER DEPARTMENT · 36,298 people · 2019 | 1/4 | SYR4 |
| Dibromoacetic Acid | 0.7886 µg/L No EPA limit set Main supplier: SEATTLE PUBLIC UTILITIES · 1,161,961 people · 2019
Highest in the ZIP: 1.31 µg/L — TUKWILA WATER DEPARTMENT · 36,298 people · 2019 | 3/4 | SYR4 |
| Chromium | 1.2 µg/L 1.2% of the EPA limit 100 µg/L Main supplier: SEATTLE PUBLIC UTILITIES · 1,161,961 people · 2012 | 1/4 | SYR4 |
| Selenium | 1.2 µg/L 2.4% of the EPA limit 50 µg/L Main supplier: SEATTLE PUBLIC UTILITIES · 1,161,961 people · 2012 | 1/4 | SYR4 |
| Bromoform | 1.018 µg/L No EPA limit set Highest in the ZIP: TUKWILA WATER DEPARTMENT · 36,298 people · 2019 | 2/4 | SYR4 |
| PFBS | 0.0030 µg/L No EPA limit set Highest in the ZIP: RENTON CITY OF · 108,091 people · 2023 | 1/4 | UCMR-5 |
| Lead | 0.0016 mg/L 11% of the EPA limit 0.0150 mg/L Main supplier: SEATTLE PUBLIC UTILITIES · 1,161,961 people · 2025
Highest in the ZIP: 0.0019 mg/L — RENTON CITY OF · 108,091 people · 2025 | 3/4 | 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.
Water suppliers serving ZIP 98178
| Supplier | State | Population served |
|---|---|---|
| SEATTLE PUBLIC UTILITIES | WA | 1,161,961 |
| RENTON CITY OF | WA | 108,091 |
| TUKWILA WATER DEPARTMENT | WA | 36,298 |
| SKYWAY WATER & SEWER | WA | 12,036 |
Frequently asked questions about ZIP 98178 tap water
Is the tap water in ZIP 98178 safe to drink?
EPA testing detected 23 contaminants across the water suppliers serving ZIP 98178. A detection isn't the same as a violation — most levels are within federal limits. See each level and source above, and your utility's annual Consumer Confidence Report for the official status.
Which water suppliers serve ZIP 98178?
4 public water suppliers report EPA drinking-water monitoring for ZIP 98178. Each is listed above with its population served.
What contaminants are in ZIP 98178's water?
EPA monitoring detected Nitrate, Nitrate-Nitrite, Fluoride, Total Haloacetic Acids (HAA5), TTHM, and others across this ZIP's suppliers. The full list with levels and sources is above.