What was found in ZIP 98074
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 | 2233.5 µg/L 22% of the EPA limit 10000 µg/L Main supplier: SAMMAMISH PLATEAU WATER & SEWER · 79,362 people · 2019 | 2/2 | SYR4 |
| Nitrate-Nitrite | 1728.4999999999998 µg/L 17% of the EPA limit 10000 µg/L Main supplier: SAMMAMISH PLATEAU WATER & SEWER · 79,362 people · 2018 | 2/2 | SYR4 |
| Fluoride | 800 µg/L 20% of the EPA limit 4000 µg/L Main supplier: SAMMAMISH PLATEAU WATER & SEWER · 79,362 people · 2018 | 1/2 | SYR4 |
| TTHM | 45.30999999999999 µg/L 57% of the EPA limit 80 µg/L Main supplier: SAMMAMISH PLATEAU WATER & SEWER · 79,362 people · 2019 | 2/2 | SYR4 |
| Chloroform | 41.47499999999999 µg/L No EPA limit set Main supplier: SAMMAMISH PLATEAU WATER & SEWER · 79,362 people · 2019 | 2/2 | SYR4 |
| Total Haloacetic Acids (HAA5) | 38.38199999999999 µg/L 64% of the EPA limit 60 µg/L Main supplier: SAMMAMISH PLATEAU WATER & SEWER · 79,362 people · 2019 | 2/2 | SYR4 |
| Copper | 30.9 µg/L 2.4% of the EPA limit 1300 µg/L Main supplier: SAMMAMISH PLATEAU WATER & SEWER · 79,362 people · 2018 | 1/2 | SYR4 |
| Trichloroacetic Acid | 22.109999999999996 µg/L No EPA limit set Main supplier: SAMMAMISH PLATEAU WATER & SEWER · 79,362 people · 2019 | 2/2 | SYR4 |
| Dichloroacetic Acid | 17.969999999999995 µg/L No EPA limit set Main supplier: SAMMAMISH PLATEAU WATER & SEWER · 79,362 people · 2019 | 1/2 | SYR4 |
| Arsenic | 6.39 µg/L 64% of the EPA limit 10 µg/L Main supplier: SAMMAMISH PLATEAU WATER & SEWER · 79,362 people · 2018
Highest in the ZIP: 6.7 µg/L — NE SAMMAMISH SEWER & WATER DISTRICT · 9,702 people · 2019 | 2/2 | SYR4 |
| Lead | 3.9 µg/L 26% of the EPA limit 15 µg/L Main supplier: SAMMAMISH PLATEAU WATER & SEWER · 79,362 people · 2018 | 1/2 | SYR4 |
| Bromodichloromethane | 3.7 µg/L No EPA limit set Main supplier: SAMMAMISH PLATEAU WATER & SEWER · 79,362 people · 2019 | 2/2 | SYR4 |
| Monochloroacetic Acid | 3.2955 µg/L No EPA limit set Main supplier: SAMMAMISH PLATEAU WATER & SEWER · 79,362 people · 2019 | 1/2 | SYR4 |
| Dibromochloromethane | 1.9819999999999998 µg/L No EPA limit set Main supplier: SAMMAMISH PLATEAU WATER & SEWER · 79,362 people · 2019 | 2/2 | SYR4 |
| Dibromoacetic Acid | 0.6603 µg/L No EPA limit set Main supplier: SAMMAMISH PLATEAU WATER & SEWER · 79,362 people · 2019 | 2/2 | SYR4 |
| Bromoform | 0.6475 µg/L No EPA limit set Main supplier: SAMMAMISH PLATEAU WATER & SEWER · 79,362 people · 2019 | 2/2 | SYR4 |
| Combined Radium (-226 And -228) | 0.5000 pCi/L 10% of the EPA limit 5 pCi/L Highest in the ZIP: NE SAMMAMISH SEWER & WATER DISTRICT · 9,702 people · 2012 | 1/2 | SYR4 |
| Cadmium | 0.2000 µg/L 4% of the EPA limit 5 µg/L Main supplier: SAMMAMISH PLATEAU WATER & SEWER · 79,362 people · 2018 | 1/2 | SYR4 |
| Asbestos | 0.1150 MFL 1.6% of the EPA limit 7 MFL Main supplier: SAMMAMISH PLATEAU WATER & SEWER · 79,362 people · 2017 | 1/2 | SYR4 |
| PFHXS | 0.0165 µg/L No EPA limit set Main supplier: SAMMAMISH PLATEAU WATER & SEWER · 79,362 people · 2024 | 1/2 | UCMR-5 |
| PFOS | 0.0111 µg/L No EPA limit set Main supplier: SAMMAMISH PLATEAU WATER & SEWER · 79,362 people · 2024 | 1/2 | UCMR-5 |
| PFBS | 0.0088 µg/L No EPA limit set Main supplier: SAMMAMISH PLATEAU WATER & SEWER · 79,362 people · 2024 | 1/2 | UCMR-5 |
| Pfhxa | 0.0043 µg/L No EPA limit set Main supplier: SAMMAMISH PLATEAU WATER & SEWER · 79,362 people · 2024 | 1/2 | UCMR-5 |
| Pfpes | 0.0041 µg/L No EPA limit set Main supplier: SAMMAMISH PLATEAU WATER & SEWER · 79,362 people · 2024 | 1/2 | UCMR-5 |
| Pfpea | 0.0039 µg/L No EPA limit set Main supplier: SAMMAMISH PLATEAU WATER & SEWER · 79,362 people · 2024 | 1/2 | UCMR-5 |
| Lead | 0.0017 mg/L 11% of the EPA limit 0.0150 mg/L Main supplier: SAMMAMISH PLATEAU WATER & SEWER · 79,362 people · 2025 | 2/2 | 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 98074
| Supplier | State | Population served |
|---|---|---|
| SAMMAMISH PLATEAU WATER & SEWER | WA | 79,362 |
| NE SAMMAMISH SEWER & WATER DISTRICT | WA | 9,702 |
Frequently asked questions about ZIP 98074 tap water
Is the tap water in ZIP 98074 safe to drink?
EPA testing detected 26 contaminants across the water suppliers serving ZIP 98074. 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 98074?
2 public water suppliers report EPA drinking-water monitoring for ZIP 98074. Each is listed above with its population served.
What contaminants are in ZIP 98074's water?
EPA monitoring detected Nitrate, Nitrate-Nitrite, Fluoride, TTHM, Chloroform, and others across this ZIP's suppliers. The full list with levels and sources is above.