City of Mercer Island
Published drinking-water records and contacts for City of Mercer Island. System WA5353640. Review sources and dates; not a real-time water assessment.
- System ID
- WA5353640
- State or territory
- WA
- Published population served
- 31057
- System type (source code)
- CWS
Published records and dates
- PFAS / lithium (EPA UCMR 5): 120 — 2023-09-12 – 2024-06-11
- Washington DOH PFAS test results: 126 — 2023-09-12 – 2025-01-22
Missing records here do not mean the provider did not test. Published records are not a real-time assessment of your tap water.
Published testing results
Selected recent records are shown below. Different sampling locations and dates are not interchangeable. These excerpts are not a complete testing history.
“<” means below the stated reporting limit, not zero. A reported measurement alone is not a safety verdict. Read an example
| Substance | Published result | Reporting limit | Sample date | Sampling location |
|---|---|---|---|---|
| 11Cl-PF3OUdS | < 0.005 µg/L | 0.005 µg/L | 2024-06-11 | Seattle Intertie / EP001 |
| 4:2 FTS | < 0.003 µg/L | 0.003 µg/L | 2024-06-11 | Seattle Intertie / EP001 |
| 6:2 FTS | < 0.005 µg/L | 0.005 µg/L | 2024-06-11 | Seattle Intertie / EP001 |
| 8:2 FTS | < 0.005 µg/L | 0.005 µg/L | 2024-06-11 | Seattle Intertie / EP001 |
| 9Cl-PF3ONS | < 0.002 µg/L | 0.002 µg/L | 2024-06-11 | Seattle Intertie / EP001 |
| ADONA | < 0.003 µg/L | 0.003 µg/L | 2024-06-11 | Seattle Intertie / EP001 |
| HFPO-DA | < 0.005 µg/L | 0.005 µg/L | 2024-06-11 | Seattle Intertie / EP001 |
| NEtFOSAA | < 0.005 µg/L | 0.005 µg/L | 2024-06-11 | Seattle Intertie / EP001 |
| NFDHA | < 0.02 µg/L | 0.02 µg/L | 2024-06-11 | Seattle Intertie / EP001 |
| NMeFOSAA | < 0.006 µg/L | 0.006 µg/L | 2024-06-11 | Seattle Intertie / EP001 |
| PFBA | < 0.005 µg/L | 0.005 µg/L | 2024-06-11 | Seattle Intertie / EP001 |
| PFBS | < 0.003 µg/L | 0.003 µg/L | 2024-06-11 | Seattle Intertie / EP001 |
| PFDA | < 0.003 µg/L | 0.003 µg/L | 2024-06-11 | Seattle Intertie / EP001 |
| PFDoA | < 0.003 µg/L | 0.003 µg/L | 2024-06-11 | Seattle Intertie / EP001 |
| PFEESA | < 0.003 µg/L | 0.003 µg/L | 2024-06-11 | Seattle Intertie / EP001 |
| PFHpA | < 0.003 µg/L | 0.003 µg/L | 2024-06-11 | Seattle Intertie / EP001 |
| PFHpS | < 0.003 µg/L | 0.003 µg/L | 2024-06-11 | Seattle Intertie / EP001 |
| PFHxA | < 0.003 µg/L | 0.003 µg/L | 2024-06-11 | Seattle Intertie / EP001 |
| PFHxS | < 0.003 µg/L | 0.003 µg/L | 2024-06-11 | Seattle Intertie / EP001 |
| PFMBA | < 0.003 µg/L | 0.003 µg/L | 2024-06-11 | Seattle Intertie / EP001 |
| PFMPA | < 0.004 µg/L | 0.004 µg/L | 2024-06-11 | Seattle Intertie / EP001 |
| PFNA | < 0.004 µg/L | 0.004 µg/L | 2024-06-11 | Seattle Intertie / EP001 |
| PFOA | < 0.004 µg/L | 0.004 µg/L | 2024-06-11 | Seattle Intertie / EP001 |
| PFOS | < 0.004 µg/L | 0.004 µg/L | 2024-06-11 | Seattle Intertie / EP001 |
| PFPeA | < 0.003 µg/L | 0.003 µg/L | 2024-06-11 | Seattle Intertie / EP001 |
| PFPeS | < 0.004 µg/L | 0.004 µg/L | 2024-06-11 | Seattle Intertie / EP001 |
| PFTA | < 0.008 µg/L | 0.008 µg/L | 2024-06-11 | Seattle Intertie / EP001 |
| PFTrDA | < 0.007 µg/L | 0.007 µg/L | 2024-06-11 | Seattle Intertie / EP001 |
| PFUnA | < 0.002 µg/L | 0.002 µg/L | 2024-06-11 | Seattle Intertie / EP001 |
| lithium | < 9 µg/L | 9 µg/L | 2024-06-11 | Seattle Intertie / EP001 |
Download all EPA UCMR 5 records (CSV)
| Substance | Published result | Sample date | Location / source |
|---|---|---|---|
| PFTA | Below a limit; numeric threshold unavailable ng/L | 2025-01-22 | 04 / Washington DOH PFAS test results |
| PFNA | Below a limit; numeric threshold unavailable ng/L | 2025-01-22 | 04 / Washington DOH PFAS test results |
| PFHxS | Below a limit; numeric threshold unavailable ng/L | 2025-01-22 | 04 / Washington DOH PFAS test results |
| PFOS | Below a limit; numeric threshold unavailable ng/L | 2025-01-22 | 04 / Washington DOH PFAS test results |
| PFTrDA | Below a limit; numeric threshold unavailable ng/L | 2025-01-22 | 04 / Washington DOH PFAS test results |
| NMeFOSAA | Below a limit; numeric threshold unavailable ng/L | 2025-01-22 | 04 / Washington DOH PFAS test results |
| HFPO-DA | Below a limit; numeric threshold unavailable ng/L | 2025-01-22 | 04 / Washington DOH PFAS test results |
| PFDoA | Below a limit; numeric threshold unavailable ng/L | 2025-01-22 | 04 / Washington DOH PFAS test results |
| NEtFOSAA | Below a limit; numeric threshold unavailable ng/L | 2025-01-22 | 04 / Washington DOH PFAS test results |
| PFUnA | Below a limit; numeric threshold unavailable ng/L | 2025-01-22 | 04 / Washington DOH PFAS test results |
| PFHpA | Below a limit; numeric threshold unavailable ng/L | 2025-01-22 | 04 / Washington DOH PFAS test results |
| ADONA | Below a limit; numeric threshold unavailable ng/L | 2025-01-22 | 04 / Washington DOH PFAS test results |
State sampling points can include untreated water. Publisher qualifiers and units are retained; consult the full source notes before interpreting a record.
Download state records with source notes (CSV)
Published compliance history
4 imported records. Status is as recorded in the source; historical records are not current advisories. Missing records do not establish that no violations occurred.
| Rule / record | Period | Recorded status | Health-based (EPA classification) | Source quarter |
|---|---|---|---|---|
| Total Coliform Rule / Monitoring, Routine Minor (TCR) | 1992-12-01 – 1992-12-31 | Archived | No | 2026Q3 |
| Total Coliform Rule / Monitoring, Routine Minor (TCR) | 1992-08-01 – 1992-08-31 | Archived | No | 2026Q3 |
| Total Coliform Rule / Monitoring, Repeat Major (TCR) | 1992-05-01 – 1992-05-31 | Archived | No | 2026Q3 |
| Total Coliform Rule / Maximum Contaminant Level Violation, Monthly (TCR) | 1992-01-01 – 1992-01-31 | Archived | Yes | 2026Q3 |
Source dates and refresh checks
A refresh check is not a sample date. Publication periods, sample dates and checks are shown separately.
- EPA SDWIS lead/copper summaries and service areas — source period: — – —; last checked: 2026-10-17
- EPA SDWIS contacts and compliance records — source period: — – —; last checked: 2026-10-17
- EPA UCMR 5 sample results — source period: 2023-01-03 – 2026-06-17; last checked: 2026-10-17
- Washington DOH PFAS test results — last successful check: 2026-10-13
An administrative filing contact may not be a customer-service line. Confirm current contact details with the provider.