Town of Coupeville water quality
Coupeville, WA · serves 4,142 people (1,478 connections) · Groundwater · Local government · EPA ID WA5315550
Data: U.S. EPA · How we read the data · How we check it
Summary
PFAS above the 2024 federal limits. Systems have until 2029 to meet the PFAS limits.
Is it an emergency? No: PFAS limits are about years of exposure, not a glass of water, and nothing in EPA's data calls for you to stop drinking the water today. If your utility ever issues a boil-water or do-not-drink notice, follow it.
- PFAS
- Above limitPFOA above the federal limit in EPA's 2023–2025 testing (PFOA 4.9 ppt vs a limit of 4 ppt, where ppt = parts per trillion).
- Lead
- Below action level3.5 ppb (parts per billion) at the 90th percentile: 9 in 10 homes sampled were at or below it. Action level 15 ppb, falling to 10 ppb in Nov 2027. Monitoring period ending Dec 2025. Your home's pipes can make yours higher.
- Violations
- None health-basedNo health-based violations since 2016.
- Pregnant, or mixing baby formula with tap water? Babies drink more water for their size, so PFAS exposure matters more for them. Consider bottled water or a filter certified for PFAS for formula, and ask your doctor. Health effects.
- To lower your PFAS exposure now, a home filter certified for PFAS reduction works (reverse osmosis, or activated carbon certified to NSF/ANSI 53 or 58). Filters for these results.
- Built before 1986, or not sure what your service line is made of? Check your service line and test your tap. Utility data can't show your pipes.
- Tested your own tap? Compare your result with these numbers. Moving? Compare this system with another.
- Read Town of Coupeville's annual water quality report (Consumer Confidence Report). It lists every regulated contaminant tested and is usually on the utility's website or mailed with your bill. EPA: how to find it.
PFAS (“forever chemicals”)
EPA UCMR 5: 1 entry point tested Mar 2025 to Aug 2025. "Average" is the highest entry-point average (non-detects counted as zero), the way EPA compares UCMR 5 results to the limits. ppt = parts per trillion. These results do not determine compliance.
| Contaminant | Highest average |
|---|---|
| PFOA Above limit Limit 4 ppt | 4.9 ppt 1.22× the limit |
| PFOS Not detected Limit 4 ppt | – |
| PFHxS Detected, below limit Limit 10 ppt | 1.9 ppt 19% of the limit |
| PFNA Not detected Limit 10 ppt | – |
| HFPO-DA (GenX) Not detected Limit 10 ppt | – |
| Hazard Index (a combined score for PFHxS, PFNA, GenX and PFBS, where above 1 is over the limit) Detected, below limit Limit 1 | 0.19 |
| PFBS Detected, below limit Guideline 2,000 ppt | 3.35 ppt |
| PFBA Detected, below limit Guideline 6,000 ppt | 2.65 ppt |
| PFHxA Detected, below limit Guideline 3,000 ppt | 11.4 ppt |
| PFPeA Detected, no limit | 11.5 ppt |
| PFHpA Detected, no limit | 1.65 ppt |
For context: the PFOA average is higher than at 98% of the Washington systems EPA tested.
29 PFAS tested, 7 detected at least once. "Not detected" means below EPA's reporting limit (about 2 to 20 ppt depending on the chemical), not proven zero. PFAS not listed were not detected. The limits for PFHxS, PFNA, GenX and the Hazard Index were proposed for rescission in May 2026. That proposal is not final. Systems have until 2029 to meet the limits.
Lithium
Not detected in 2 samples (reporting limit 9 ppb). About lithium.
Lead and copper
Latest 90th percentile: 3.5 ppb lead (Jan 2023 – Dec 2025). Below action level
Highest since 2016: 4.1 ppb (Dec 2016).
| Monitoring period | Lead (90th pct.) |
|---|---|
| Jan 2023 – Dec 2025 | 3.5 ppb |
| Jan 2020 – Dec 2022 | 3.9 ppb |
| Jan 2017 – Dec 2019 | 1.8 ppb |
Earlier results (8)
| Jan 2014 – Dec 2016 | 4.1 ppb |
| Jan 2011 – Dec 2013 | 3.1 ppb |
| Jan 2008 – Dec 2010 | 5 ppb |
| Jan 2007 – Dec 2007 | 1 ppb |
| Jan 2005 – Dec 2005 | 4 ppb |
| Jan 2004 – Jun 2004 | 4 ppb |
| Jul 2001 – Dec 2001 | 1.6 ppb |
| Jul 1993 – Dec 1993 | 11 ppb |
Lead comes from pipes and fixtures, not the source water, so it varies home to home. The 90th percentile means 9 in 10 sampled homes were at or below it. More on lead.
Violations
Health-based violations mean a contaminant exceeded a limit or a required treatment step was missed. Monitoring and reporting violations mean required tests or reports were late or missing, so the water's quality during that time is unknown. The total includes every violation in EPA's records, most of them paperwork.
Where it serves
Coupeville
ZIP codes the system reported serving: 98239
Nearby utilities
- Marysville Utilities Marysville · 26 mi
- City of Everett Public Works Dept. Everett · 29 mi
- Snohomish County Public Utility District 1 – Lake Stevens Lake Stevens · 31 mi
- Alderwood Water District North Lynnwood · 31 mi
- City of Lynnwood Lynnwood · 32 mi
- Northshore Utility District Kenmore · 38 mi
Questions
Is Town of Coupeville water safe to drink?
Town of Coupeville has no health-based violations since 2016. EPA testing found PFAS above the 2024 federal limits, which systems must meet by 2029. Federal data can't tell you about your own pipes: lead comes from service lines and plumbing, so test your tap if your home was built before 1986. For the official word, read the utility's annual Consumer Confidence Report.
Does Town of Coupeville water have PFAS?
Yes. EPA's 2023–2025 testing of Town of Coupeville found 7 PFAS at least once. The highest entry-point averages were above the federal limit for PFOA: PFOA 4.9 ppt (limit 4 ppt for PFOA and PFOS, 10 ppt for the others).
What is the lead level in Town of Coupeville water?
The most recent 90th-percentile lead result for Town of Coupeville is 3.5 ppb, for the period ending Dec 2025. The federal action level is 15 ppb, falling to 10 ppb in November 2027. The 90th percentile means 9 in 10 homes sampled were at or below this number. Individual homes can be higher.
Check these numbers yourself
Every figure on this page comes from public EPA records. You don't have to take our word for it:
- EPA's own report for WA5315550: violations, enforcement and inspections, straight from EPA.
- EPA UCMR 5 data: the PFAS and lithium results (search the file for PWSID WA5315550).
- EPA SDWIS download: the lead results, population and violation records we use.
- The utility's annual water quality report (Consumer Confidence Report): ask Town of Coupeville, or see EPA's guide to finding it.
Found something that doesn't match? Tell us and we'll check it against EPA's records. How we check our data.
Source: U.S. EPA drinking water records and PFAS testing (UCMR 5). How we read the data.