Washington
Water quality data from the EPA Safe Drinking Water Information System
Water Systems
10,086
Active public water systems
Population Served
9.86M
Residents with piped water
Lead Violations
61
Systems exceeding 15 ppb
Copper Violations
443
Lead & Copper Rule
Average Lead Level
EPA Action Level: 15 ppb
MCLG (health goal): 0 ppb
Average across 3198 systems with reported lead data.
Violations Detected
504 water systems in Washington have reported violations under the Lead and Copper Rule. These utilities are required to notify customers and take corrective action.
Water Systems: Highest Lead Levels
| System Name | City | Population | Lead Level | Status | Sample Date |
|---|---|---|---|---|---|
| Kenmore | 105,105 | 36.00 ppb | Violation | 1992-12-31 | |
| Lynnwood | 200,000 | 28.00 ppb | Violation | 1992-06-30 | |
| Tumwater | 66,373 | 8.00 ppb | OK | 2019-12-31 | |
| Cheney | 17,108 | 6.50 ppb | OK | 2023-12-31 | |
| PUYALLUP | 15,313 | 6.40 ppb | OK | 2023-12-31 | |
| Lacey | 103,755 | 6.00 ppb | OK | 2016-12-31 | |
| Ferndale | 19,305 | 5.60 ppb | OK | 2024-12-31 | |
| Kent | 115,950 | 5.20 ppb | OK | 2022-12-31 | |
| Bremerton | 70,913 | 5.00 ppb | OK | 2023-12-31 | |
| Pullman | 21,506 | 4.90 ppb | OK | 2024-12-31 | |
| OLYMPIA | 113,584 | 4.20 ppb | OK | 2022-12-31 | |
| TACOMA | 10,850 | 4.00 ppb | OK | 1998-12-31 | |
| Port Townsend | 16,977 | 3.70 ppb | OK | 2022-12-31 | |
| Seattle | 1,091,904 | 3.50 ppb | OK | 2024-12-31 | |
| Everett | 215,774 | 3.50 ppb | OK | 2024-12-31 |
Showing top 15 of 3134 systems with lead data. Action level: 15 ppb.
Systems With Active Violations
These water systems have exceeded EPA limits and must take corrective action.
TACOMA · Pop. 448,771
Lead: 1.00 ppb (2022-12-31)
Vancouver · Pop. 373,047
Lead: 2.20 ppb (2023-12-31)
Lynnwood · Pop. 200,000
Lead: 28.00 ppb (1992-06-30)
Kent · Pop. 166,421
Lead: 0.00 ppb (2024-12-31)
FEDERAL WAY · Pop. 118,273
Lead: 1.10 ppb (2022-12-31)
Kennewick · Pop. 114,468
Lead: 1.90 ppb (2022-12-31)
OLYMPIA · Pop. 113,584
Lead: 4.20 ppb (2022-12-31)
Auburn · Pop. 113,095
Lead: 2.20 ppb (2024-12-31)
Yakima · Pop. 112,858
Lead: 0.00 ppb (2024-12-31)
Renton · Pop. 107,119
Lead: 1.60 ppb (2022-12-31)
Kenmore · Pop. 105,105
Lead: 36.00 ppb (1992-12-31)
Sammamish · Pop. 79,362
Lead: 1.50 ppb (2022-12-31)
Water Source Types
Air Quality
GoodAvg AQI
33.5
PM2.5
4.8 µg/m³
Unhealthy Days
3
Primary Pollutant
Wildfire smoke (seasonal)
Source: EPA AirNow & American Lung Association 2024 State of the Air. AQI scale: 0–50 Good · 51–100 Moderate · 101–150 Sensitive Groups · 151+ Unhealthy.
PFAS Contamination
Low DetectionPFAS (per- and polyfluoroalkyl substances), known as “forever chemicals,” are a group of synthetic chemicals that persist indefinitely in the environment and human body. The EPA set a maximum contaminant level (MCL) of 4 parts per trillion (ppt) for PFOA and PFOS in April 2024. View national PFAS tracker →
Systems Tested
1,261
PFAS Detected
249
Detection Rate
19.7%
Exceeding MCL (4 ppt)
28(2.2%)
Highest recorded level: 45 ppt (EPA MCL: 4 ppt). State has own MCL standards and extensive monitoring: 1,261 Group A water systems evaluated; 249 with PFAS detected (~20% rate) per WA Dept of Health dashboard. State data directly sourced