Is Sammamish, WA Tap Water Safe to Drink?
Sammamish tap water meets federal Safe Drinking Water Act standards but 2 of 2 ZIP codes show detections above EPA health guidelines, primarily for PFHxS. A certified filter is recommended for households that want an additional layer of protection.
Where Does Sammamish Get Its Water?
Water in Sammamish, WA is provided by 2 public water systems: NE SAMMAMISH SEWER & WATER DISTRICT and SAMMAMISH PLATEAU WATER & SEWER.
How Is Sammamish Tap Water Treated?
Treatment includes granular activated carbon filtration, groundwater disinfection and in-line filtration.
What's in Sammamish Tap Water?
The following contaminants were detected most frequently in Sammamish public water systems. 2 of 2 ZIP codes showed detections above EPA health guidelines.
| Contaminant | Peak detected | EPA guideline | ZIPs detected | Status |
|---|---|---|---|---|
| PFHxS | 0.0131 µg/L | 0.004 µg/L | 2 ZIPs | Above guideline |
| lithium | 9 µg/L | — | 0 ZIPs | Within guideline |
| PFTrDA | 0.007 µg/L | — | 0 ZIPs | Within guideline |
| 6:2 FTS | 0.005 µg/L | — | 0 ZIPs | Within guideline |
| 8:2 FTS | 0.005 µg/L | — | 0 ZIPs | Within guideline |
Health Risk Profile for Sammamish
Based on EPA monitoring data, 2 of 2 ZIP codes in Sammamish have recorded detections above EPA health guidelines. Sensitive populations such as infants, pregnant individuals, and those with weakened immune systems may benefit from an additional layer of protection such as a certified point-of-use filter.
Best Filters for PFAS Water Profile
PFAS compounds are detected in this water supply. A reverse osmosis (RO) system or an activated-carbon filter specifically certified under NSF/ANSI P473 is required for reliable PFAS reduction. Standard pitcher and faucet filters without P473 certification do not remove PFAS.
8-stage tankless RO system certified to NSF/ANSI 58, reduces 1,000+ contaminants including PFAS, lead, arsenic, fluoride, and nitrates.
NSF-certified dual-layer filtration reduces 70+ contaminants including PFAS, lead, chlorine, microplastics, and bacteria.
See recommendations matched to your exact address: choose your ZIP code below.
Frequently Asked Questions about Sammamish Tap Water
Is Sammamish tap water safe to drink?
Sammamish tap water meets Safe Drinking Water Act requirements but 2 of 2 ZIP codes show contaminant levels above EPA health-based guidelines. A certified point-of-use filter adds an extra layer of protection.
What contaminants are in Sammamish tap water?
The most commonly detected contaminants in Sammamish water systems include: PFHxS, lithium, PFTrDA. See the ZIP-level reports for exact measurements and EPA guideline comparisons.
Where does Sammamish get its drinking water?
Sammamish receives water from 2 public water systems, including NE SAMMAMISH SEWER & WATER DISTRICT.
Do I need a water filter in Sammamish?
If your ZIP code is among those with detections above EPA health guidelines, choose a filter certified for the specific contaminants shown in your ZIP report. Reverse osmosis is generally the broadest option for PFAS, lithium, and many other dissolved contaminants.
How often is Sammamish tap water tested?
Public water systems in Sammamish are required by the EPA to test for regulated contaminants on schedules ranging from daily (for microbials and disinfectants) to annual or triennial (for many chemical contaminants). Results are published in annual Consumer Confidence Reports (CCRs). The data on this page reflects the most recent available EPA monitoring results, with the latest sample date of 2025-09-22.
Tap water reports by ZIP in Sammamish
- 98074 - Seattle East CCD, Sammamish tap water report Higher concern
- 98075 - Issaquah Plateau CCD, Sammamish tap water report Higher concern
Water utilities serving Sammamish, WA
Service area boundaries are approximate and based on state filings or modeled estimates. Contact your utility to confirm exact service at a specific address.
- SAMMAMISH PLATEAU WATER & SEWERAction advised
Also covers / overlaps with
- Issaquah Plateau CCD, WA · Township
- Seattle East CCD, WA · Township