PFOS
2.8× the limitPerfluorooctanesulfonic acid
11.1ng/L
Each block = 4.0 ng/L federal MCL (2024)
EPA UCMR 5 · sampled 2023Evidence
City water report · 2026
Is Sammamish Tap Water Safe? 2026 Water Quality Report
Short answer: Two PFAS, PFHxS and PFOS, are above their federal limits (2024 limits that water systems have until at least 2029 to meet); 2 more are detected with no federal limit, and everything else measured is within its reference or not detected. Sammamish Plateau Water & Sewer serves 79,362 residents.
Likely match, check your bill
SAMMAMISH PLATEAU WATER & SEWER serves Sammamish
Your water bill or annual water quality report names your actual supplier.
- Source
- Surface water
- Lead service lines
- 0 lead, 17,213 unknown
- SAMMAMISH PLATEAU WATER & SEWERThis reportWA5340900 · 79,362 served
What stands out
Two PFAS above the 2024 federal limit
Each bar is drawn in blocks of its own limit, so the length shows how far above it the result sits.
PFHxS
1.6× the limitPerfluorohexanesulfonic acid
16.5ng/L
Each block = 10 ng/L federal MCL (2024)
EPA UCMR 5 · sampled 2023Evidence
Coverage by group
31 results on record- PFAS (forever chemicals)2 above · 4 detected · 23 not detected
- Metals & lead1 detected
- Disinfection by-productsNot monitored
- Other1 not detected
Every detected result
7 detected results, by distance from their limit
SAMMAMISH PLATEAU WATER & SEWER (EPA PWSID WA5340900) delivers surface water to 79,362 residents. This report reflects 29 individual PFAS result(s) from the source UCMR5 observations and the latest Lead & Copper Rule 90th-percentile result. Water hardness and disinfectant type are pending the utility's own annual report.
- Perfluorooctanesulfonic acid (PFOS)EPA UCMR 5 · 20234.0 ng/L federal MCL (2024)11.1ng/LAbove limit
- Perfluorohexanesulfonic acid (PFHxS)EPA UCMR 5 · 202310 ng/L federal MCL (2024)16.5ng/LAbove limit
- Lead (90th percentile)EPA SDWIS (Lead & Copper Rule) · 202315 µg/L federal action level1.7µg/LWithin reference
- Perfluorobutanesulfonic acid (PFBS)EPA UCMR 5 · 20232,000 ng/L EPA health advisory (screening, not a legal limit)8.8ng/LWithin reference
- Perfluorohexanoic acid (PFHxA)EPA UCMR 5 · 2023400,000 ng/L Michigan EGLE state MCL (strictest US state)4.3ng/LWithin reference
- Perfluoropentanesulfonic acid (PFPeS)EPA UCMR 5 · 2023No federal or state limit; shown for transparency4.1ng/LDetected · no limit
- Perfluoropentanoic acid (PFPeA)EPA UCMR 5 · 2023No federal or state limit; shown for transparency3.9ng/LDetected · no limit
24 other contaminants tested, none detected
- 11Cl-PF3OUdS
- 4:2 FTS
- 6:2 FTS
- 8:2 FTS
- 9Cl-PF3ONS
- ADONA
- HFPO-DA (GenX)
- NEtFOSAA
- NFDHA
- NMeFOSAA
- PFBA
- PFDA
- PFDoA
- PFEESA
- PFHpA
- PFHpS
- PFMBA
- PFMPA
- PFNA
- PFOA
- PFTA
- PFTrDA
- PFUnA
- Lithium
Track record
0health-based violations in the last 10 years
From EPA SDWIS. A clean violation history means no enforcement action was recorded; it does not cover contaminants without a limit.
Not in this recordDisinfection by-products weren't monitored in this dataset
No result is not a pass. Your utility's annual water quality report may list them, and a certified lab test covers your own tap.
What you can do
Test first, then treat what was found
- 01 · TestTest your own tap
Plumbing inside a home can add lead that the system record can't show. A tap test tells you what reaches your glass.
Certified labHow to test your tap → - 02 · Treat PFASReverse osmosis, or carbon certified for PFAS
PFOS 11.1 ng/L, above the 4 ng/L limit (+5 more PFAS detected)
NSF/ANSI 58 or 53, with PFHxS/PFOS/PFBS/PFHxA/PFPeA/PFPeS named on the listingTreatment for PFAS → - 03 · LeadLead-certified carbon filter, or reverse osmosis
lead 1.7 µg/L, below the 15 µg/L action level
NSF/ANSI 53 (lead)Treatment for Lead →
Test your own tap
Screening tells you if something is worth a closer look; a lab result is the number you can act on.
As an Amazon Associate, PurityMap earns from qualifying purchases. Affiliate disclosure.
Screening: quick check, not lab-grade
Safe Home DIY Lead in Drinking Water Combo Test Kit
Safe Home (EnviroTestKits)
Lead, read as one of three ranges: 0–4, 5–15 or 15+ ppb
- Turnaround: 5 minutes
What it can't tell you: It shows a lead range, not an exact level, and tests nothing else unless you pay extra for the optional lab test.
Lab-certified results
ETR Labs Basic Water Quality Test Kit
ETR Laboratories
50+ substances, including lead, copper, arsenic, nitrate, hardness and coliform bacteria
- Analyzed by Environmental Testing and Research Laboratories (ETR Labs), Leominster, MA · ISO/IEC 17025:2017, ANAB certificate AT-2638
- Turnaround: 2–4 business days after the lab receives it
What it can't tell you: It does not test PFAS, and not every result on the panel falls under the lab's accredited scope.
When your results arrive, read them here →
Commercial
Certified for a concern found here
Each card names which Sammamish findings its current certification covers, and which it doesn't.
As an Amazon Associate, PurityMap earns from qualifying purchases. A product appears here only when a current certification record covers at least one identified concern; every concern stays listed. The retail offer is looked up afterwards and never changes which products appear or their order. Affiliate disclosure.
Under-Sink Filter
Aquasana Claryum 2-Stage Under-Sink Filter (AQ-5200)
- PFOS: eligible, evidence match
- Lead: eligible, evidence match
- Not established: PFHxS, Perfluorobutanesulfonic acid (PFBS), Perfluorohexanoic acid (PFHxA) and 2 more
Not suitable for (5)
- Treating every tap in the home
- A whole-home hard-water or scale problem
- All PFAS: its evidence covers only the compounds it names
- Anyone who can't plumb, drill or hire an installer
- Renters who can't modify plumbing
Under-Sink Filter
Aquasana Claryum 3-Stage Max Flow Under-Sink Filter (AQ-6300M)
- PFOS: eligible, evidence match
- Lead: eligible, evidence match
- Not established: PFHxS, Perfluorobutanesulfonic acid (PFBS), Perfluorohexanoic acid (PFHxA) and 2 more
Not suitable for (5)
- Treating every tap in the home
- A whole-home hard-water or scale problem
- All PFAS: its evidence covers only the compounds it names
- Anyone who can't plumb, drill or hire an installer
- Renters who can't modify plumbing
See all 13 products certified for a Sammamish concern →
Countertop System
Aquasana Clean Water Machine Countertop Filter (AQ-CWM2)
- PFOS: eligible, evidence match
- Lead: eligible, evidence match
- Not established: PFHxS, Perfluorobutanesulfonic acid (PFBS), Perfluorohexanoic acid (PFHxA) and 2 more
Not suitable for (3)
- Treating every tap in the home
- A whole-home hard-water or scale problem
- All PFAS: its evidence covers only the compounds it names
Countertop System
Patriot Pure Ultimate Water Filtration System
- PFOS: eligible, evidence match
- Lead: eligible, evidence match
- Not established: PFHxS, Perfluorobutanesulfonic acid (PFBS), Perfluorohexanoic acid (PFHxA) and 2 more
Not suitable for (3)
- Treating every tap in the home
- A whole-home hard-water or scale problem
- All PFAS: its evidence covers only the compounds it names
Countertop System
AquaTru Carafe Countertop Reverse-Osmosis Purifier (AT100)
- PFOS: eligible, evidence match
- Lead: eligible, evidence match
- Not established: PFHxS, Perfluorobutanesulfonic acid (PFBS), Perfluorohexanoic acid (PFHxA) and 2 more
Not suitable for (3)
- Treating every tap in the home
- A whole-home hard-water or scale problem
- All PFAS: its evidence covers only the compounds it names
Countertop System
AquaTru Classic Countertop Reverse-Osmosis Purifier (AT2000)
- PFOS: eligible, evidence match
- Lead: eligible, evidence match
- Not established: PFHxS, Perfluorobutanesulfonic acid (PFBS), Perfluorohexanoic acid (PFHxA) and 2 more
Not suitable for (3)
- Treating every tap in the home
- A whole-home hard-water or scale problem
- All PFAS: its evidence covers only the compounds it names
Under-Sink Filter
Waterdrop G3P600 Tankless Reverse-Osmosis System
- PFOS: eligible, evidence match
- Lead: eligible, evidence match
- Not established: PFHxS, Perfluorobutanesulfonic acid (PFBS), Perfluorohexanoic acid (PFHxA) and 2 more
Not suitable for (5)
- Treating every tap in the home
- A whole-home hard-water or scale problem
- All PFAS: its evidence covers only the compounds it names
- Anyone who can't plumb, drill or hire an installer
- Renters who can't modify plumbing
Under-Sink Filter
Waterdrop G3P800 Tankless Reverse-Osmosis System
- PFOS: eligible, evidence match
- Lead: eligible, evidence match
- Not established: PFHxS, Perfluorobutanesulfonic acid (PFBS), Perfluorohexanoic acid (PFHxA) and 2 more
Not suitable for (5)
- Treating every tap in the home
- A whole-home hard-water or scale problem
- All PFAS: its evidence covers only the compounds it names
- Anyone who can't plumb, drill or hire an installer
- Renters who can't modify plumbing
Refrigerator Filter
Whirlpool Filter 3 Refrigerator Water Filter (WHR3RXD1)
- PFOS: eligible, evidence match
- Lead: eligible, evidence match
- Not established: PFHxS, Perfluorobutanesulfonic acid (PFBS), Perfluorohexanoic acid (PFHxA) and 2 more
Not suitable for (3)
- Treating every tap in the home
- A whole-home hard-water or scale problem
- All PFAS: its evidence covers only the compounds it names
Water Pitcher
Brita Elite Water Filter Pitcher
- Lead: eligible, evidence match
- Not established: PFHxS, PFOS, Perfluorobutanesulfonic acid (PFBS) and 3 more
Not suitable for (3)
- Treating every tap in the home
- A whole-home hard-water or scale problem
- All PFAS: its evidence covers only the compounds it names
Water Pitcher
Culligan ZeroWater 10-Cup Pitcher (ZEROP10)
- Lead: eligible, evidence match
- Not established: PFHxS, PFOS, Perfluorobutanesulfonic acid (PFBS) and 3 more
Not suitable for (3)
- Treating every tap in the home
- A whole-home hard-water or scale problem
- All PFAS: its evidence covers only the compounds it names
Faucet Attachment
PUR Plus Faucet Filter (FM2500V)
- Lead: eligible, evidence match
- Not established: PFHxS, PFOS, Perfluorobutanesulfonic acid (PFBS) and 3 more
Not suitable for (3)
- Treating every tap in the home
- A whole-home hard-water or scale problem
- All PFAS: its evidence covers only the compounds it names
Under-Sink Filter
Frizzlife SP99 Under-Sink Filter
- Lead: eligible, evidence match
- Not established: PFHxS, PFOS, Perfluorobutanesulfonic acid (PFBS) and 3 more
Not suitable for (4)
- Treating every tap in the home
- A whole-home hard-water or scale problem
- All PFAS: its evidence covers only the compounds it names
- Anyone who can't plumb, drill or hire an installer
Questions
Frequently asked questions
Is Sammamish tap water safe to drink?
PurityMap does not give a safe/unsafe verdict; it shows what the public records measured. For Sammamish, PFOS 11.1 ng/L (limit 4 ng/L) and PFHxS 16.5 ng/L (limit 10 ng/L) were measured above their limits in EPA's 2024 testing; the lead 90th-percentile result was 1.7 µg/L against the 15 µg/L action level. SAMMAMISH PLATEAU WATER & SEWER (PWSID WA5340900) has a Purity Score of 55/100 (confidence: moderate), assessed at the water-system level and computed only from contaminants that were measured. Water can change in your own pipes, so a certified test is the only way to know what comes out of your tap.
Who provides tap water in Sammamish?
SAMMAMISH PLATEAU WATER & SEWER (PWS ID WA5340900) is the public water system on record for Sammamish, Washington, serving about 79,362 people. Confirm the utility on your water bill before acting on a specific finding.
Where does Sammamish get its drinking water?
Surface water (primary source of record in EPA SDWIS).
Are PFAS "forever chemicals" in Sammamish's water?
Yes. In EPA's UCMR 5 testing (2023-05-15 to 2024-02-12), PFOS was measured at 11.1 ng/L against a 4 ng/L federal limit and PFHxS was measured at 16.5 ng/L against a 10 ng/L federal limit. PFBS (8.8 ng/L, below the 2,000 ng/L EPA health advisory) and PFHxA (4.3 ng/L, below the 400,000 ng/L state limit) were also detected. PFPeA (3.9 ng/L) and PFPeS (4.1 ng/L) were also detected; they have no federal or state limit. Reverse osmosis and filters certified to NSF/ANSI 53 for PFOA/PFOS reduce them at the tap.
Is there lead in Sammamish's tap water?
SAMMAMISH PLATEAU WATER & SEWER's most recent lead 90th-percentile result (2023–2025) was 1.7 µg/L, below the 15 µg/L action level. That figure comes from sampled homes; lead usually enters from a building's own pipes and fixtures, so only a test at your tap tells you what you drink.
What does the latest Sammamish water report show?
PurityMap's current record for Sammamish holds 31 findings: 2 above a reference, 3 detected within the reference, 2 detected with no limit and 24 not detected. Each finding links to its dated public record; a parameter that was never monitored is shown as pending, not as a pass.
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Sources and dataAll 31 records and their sourcesEPA UCMR 5 · EPA SDWIS (Lead & Copper Rule)
| Contaminant | Result | Benchmark | Status | Sampled | Source |
|---|---|---|---|---|---|
| Perfluorooctanesulfonic acid (PFOS) | 11.1 ng/L | 4.0 ng/L federal MCL (2024) | Above a historical reference; current applicability unverified | 2023-05-15 to 2024-02-12 | UCMR5 Analytical Results: SAMMAMISH PLATEAU WATER & SEWER (WA5340900) |
| Perfluorohexanesulfonic acid (PFHxS) | 16.5 ng/L | 10 ng/L federal MCL (2024) | Above a historical reference; current applicability unverified | 2023-05-15 to 2024-02-12 | UCMR5 Analytical Results: SAMMAMISH PLATEAU WATER & SEWER (WA5340900) |
| Lead (90th percentile) | 1.7 µg/L | 15 µg/L federal action level | Below the listed reference | 2023–2025 monitoring period | Lead & Copper Rule 90th-percentile: SAMMAMISH PLATEAU WATER & SEWER (WA5340900) |
| Perfluorobutanesulfonic acid (PFBS) | 8.8 ng/L | 2,000 ng/L EPA health advisory (screening, not a legal limit)Screening level, not a legal limit | Within the referenced health-based guidance value | 2023-05-15 to 2024-02-12 | UCMR5 Analytical Results: SAMMAMISH PLATEAU WATER & SEWER (WA5340900) |
| Perfluorohexanoic acid (PFHxA) | 4.3 ng/L | 400,000 ng/L Michigan EGLE state MCL (strictest US state) | Within a historical reference; current applicability unverified | 2023-05-15 to 2024-02-12 | UCMR5 Analytical Results: SAMMAMISH PLATEAU WATER & SEWER (WA5340900) |
| Perfluoropentanesulfonic acid (PFPeS) | 4.1 ng/L | No federal or state limit; shown for transparency | Detected, no limit | 2023-05-15 to 2024-02-12 | UCMR5 Analytical Results: SAMMAMISH PLATEAU WATER & SEWER (WA5340900) |
| Perfluoropentanoic acid (PFPeA) | 3.9 ng/L | No federal or state limit; shown for transparency | Detected, no limit | 2023-05-15 to 2024-02-12 | UCMR5 Analytical Results: SAMMAMISH PLATEAU WATER & SEWER (WA5340900) |
24 other contaminants tested — none detected
| Contaminant | Result | Benchmark | Status | Sampled | Source |
|---|---|---|---|---|---|
| 11-Chloroeicosafluoro-3-oxaundecane-1-sulfonic acid (11Cl-PF3OUdS) | < 5 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-05-15 to 2024-02-12 | UCMR5 Analytical Results: SAMMAMISH PLATEAU WATER & SEWER (WA5340900) |
| 1H, 1H, 2H, 2H-perfluorodecane sulfonic acid (8:2 FTS) | < 5 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-05-15 to 2024-02-12 | UCMR5 Analytical Results: SAMMAMISH PLATEAU WATER & SEWER (WA5340900) |
| 1H, 1H, 2H, 2H-perfluorohexane sulfonic acid (4:2 FTS) | < 3 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-05-15 to 2024-02-12 | UCMR5 Analytical Results: SAMMAMISH PLATEAU WATER & SEWER (WA5340900) |
| 1H, 1H, 2H, 2H-perfluorooctane sulfonic acid (6:2 FTS) | < 5 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-05-15 to 2024-02-12 | UCMR5 Analytical Results: SAMMAMISH PLATEAU WATER & SEWER (WA5340900) |
| 4,8-Dioxa-3H-perfluorononanoic acid (ADONA) | < 3 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-05-15 to 2024-02-12 | UCMR5 Analytical Results: SAMMAMISH PLATEAU WATER & SEWER (WA5340900) |
| 9-Chlorohexadecafluoro-3-oxanone-1-sulfonic acid (9Cl-PF3ONS) | < 2 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-05-15 to 2024-02-12 | UCMR5 Analytical Results: SAMMAMISH PLATEAU WATER & SEWER (WA5340900) |
| Hexafluoropropylene oxide dimer acid (HFPO-DA) (GenX chemicals) | < 5 ng/L | 10 ng/L federal MCL (2024) | Not detected above the reporting limit | 2023-05-15 to 2024-02-12 | UCMR5 Analytical Results: SAMMAMISH PLATEAU WATER & SEWER (WA5340900) |
| Lithium | < 9 µg/L | 10 µg/L EPA health reference level (screening, not a legal limit)Screening level, not a legal limit | Not detected above the reporting limit | 2023-05-15 to 2024-02-12 | UCMR5 Analytical Results: SAMMAMISH PLATEAU WATER & SEWER (WA5340900) |
| N-ethyl perfluorooctanesulfonamidoacetic acid (NEtFOSAA) | < 5 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-05-15 to 2024-02-12 | UCMR5 Analytical Results: SAMMAMISH PLATEAU WATER & SEWER (WA5340900) |
| N-methyl perfluorooctanesulfonamidoacetic acid (NMeFOSAA) | < 6 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-05-15 to 2024-02-12 | UCMR5 Analytical Results: SAMMAMISH PLATEAU WATER & SEWER (WA5340900) |
| Nonafluoro-3,6-dioxaheptanoic acid (NFDHA) | < 20 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-05-15 to 2024-02-12 | UCMR5 Analytical Results: SAMMAMISH PLATEAU WATER & SEWER (WA5340900) |
| Perfluoro (2-ethoxyethane) sulfonic acid (PFEESA) | < 3 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-05-15 to 2024-02-12 | UCMR5 Analytical Results: SAMMAMISH PLATEAU WATER & SEWER (WA5340900) |
| Perfluoro-3-methoxypropanoic acid (PFMPA) | < 4 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-05-15 to 2024-02-12 | UCMR5 Analytical Results: SAMMAMISH PLATEAU WATER & SEWER (WA5340900) |
| Perfluoro-4-methoxybutanoic acid (PFMBA) | < 3 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-05-15 to 2024-02-12 | UCMR5 Analytical Results: SAMMAMISH PLATEAU WATER & SEWER (WA5340900) |
| Perfluorobutanoic acid (PFBA) | < 5 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-05-15 to 2024-02-12 | UCMR5 Analytical Results: SAMMAMISH PLATEAU WATER & SEWER (WA5340900) |
| Perfluorodecanoic acid (PFDA) | < 3 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-05-15 to 2024-02-12 | UCMR5 Analytical Results: SAMMAMISH PLATEAU WATER & SEWER (WA5340900) |
| Perfluorododecanoic acid (PFDoA) | < 3 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-05-15 to 2024-02-12 | UCMR5 Analytical Results: SAMMAMISH PLATEAU WATER & SEWER (WA5340900) |
| Perfluoroheptanesulfonic acid (PFHpS) | < 3 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-05-15 to 2024-02-12 | UCMR5 Analytical Results: SAMMAMISH PLATEAU WATER & SEWER (WA5340900) |
| Perfluoroheptanoic acid (PFHpA) | < 3 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-05-15 to 2024-02-12 | UCMR5 Analytical Results: SAMMAMISH PLATEAU WATER & SEWER (WA5340900) |
| Perfluorononanoic acid (PFNA) | < 4 ng/L | 10 ng/L federal MCL (2024) | Not detected above the reporting limit | 2023-05-15 to 2024-02-12 | UCMR5 Analytical Results: SAMMAMISH PLATEAU WATER & SEWER (WA5340900) |
| Perfluorooctanoic acid (PFOA) | < 4 ng/L | 4.0 ng/L federal MCL (2024) | Not detected above the reporting limit | 2023-05-15 to 2024-02-12 | UCMR5 Analytical Results: SAMMAMISH PLATEAU WATER & SEWER (WA5340900) |
| Perfluorotetradecanoic acid (PFTA) | < 8 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-05-15 to 2024-02-12 | UCMR5 Analytical Results: SAMMAMISH PLATEAU WATER & SEWER (WA5340900) |
| Perfluorotridecanoic acid (PFTrDA) | < 7 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-05-15 to 2024-02-12 | UCMR5 Analytical Results: SAMMAMISH PLATEAU WATER & SEWER (WA5340900) |
| Perfluoroundecanoic acid (PFUnA) | < 2 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-05-15 to 2024-02-12 | UCMR5 Analytical Results: SAMMAMISH PLATEAU WATER & SEWER (WA5340900) |
Perfluorooctanesulfonic acid (PFOS)
- Result
- 11.1 ng/L
- Benchmark
- 4.0 ng/L federal MCL (2024)
- Status
- Above a historical reference; current applicability unverified
- Sampled
- 2023-05-15 to 2024-02-12
Perfluorohexanesulfonic acid (PFHxS)
- Result
- 16.5 ng/L
- Benchmark
- 10 ng/L federal MCL (2024)
- Status
- Above a historical reference; current applicability unverified
- Sampled
- 2023-05-15 to 2024-02-12
- Result
- 1.7 µg/L
- Benchmark
- 15 µg/L federal action level
- Status
- Below the listed reference
- Sampled
- 2023–2025 monitoring period
Perfluorobutanesulfonic acid (PFBS)
- Result
- 8.8 ng/L
- Benchmark
- 2,000 ng/L EPA health advisory (screening, not a legal limit)Screening level, not a legal limit
- Status
- Within the referenced health-based guidance value
- Sampled
- 2023-05-15 to 2024-02-12
Perfluorohexanoic acid (PFHxA)
- Result
- 4.3 ng/L
- Benchmark
- 400,000 ng/L Michigan EGLE state MCL (strictest US state)
- Status
- Within a historical reference; current applicability unverified
- Sampled
- 2023-05-15 to 2024-02-12
Perfluoropentanesulfonic acid (PFPeS)
- Result
- 4.1 ng/L
- Benchmark
- No federal or state limit; shown for transparency
- Status
- Detected, no limit
- Sampled
- 2023-05-15 to 2024-02-12
Perfluoropentanoic acid (PFPeA)
- Result
- 3.9 ng/L
- Benchmark
- No federal or state limit; shown for transparency
- Status
- Detected, no limit
- Sampled
- 2023-05-15 to 2024-02-12
24 other contaminants tested — none detected
11-Chloroeicosafluoro-3-oxaundecane-1-sulfonic acid (11Cl-PF3OUdS)
- Result
- < 5 ng/L
- Benchmark
- No federal or state limit; shown for transparency
- Status
- Not detected above the reporting limit
- Sampled
- 2023-05-15 to 2024-02-12
1H, 1H, 2H, 2H-perfluorodecane sulfonic acid (8:2 FTS)
- Result
- < 5 ng/L
- Benchmark
- No federal or state limit; shown for transparency
- Status
- Not detected above the reporting limit
- Sampled
- 2023-05-15 to 2024-02-12
1H, 1H, 2H, 2H-perfluorohexane sulfonic acid (4:2 FTS)
- Result
- < 3 ng/L
- Benchmark
- No federal or state limit; shown for transparency
- Status
- Not detected above the reporting limit
- Sampled
- 2023-05-15 to 2024-02-12
1H, 1H, 2H, 2H-perfluorooctane sulfonic acid (6:2 FTS)
- Result
- < 5 ng/L
- Benchmark
- No federal or state limit; shown for transparency
- Status
- Not detected above the reporting limit
- Sampled
- 2023-05-15 to 2024-02-12
4,8-Dioxa-3H-perfluorononanoic acid (ADONA)
- Result
- < 3 ng/L
- Benchmark
- No federal or state limit; shown for transparency
- Status
- Not detected above the reporting limit
- Sampled
- 2023-05-15 to 2024-02-12
9-Chlorohexadecafluoro-3-oxanone-1-sulfonic acid (9Cl-PF3ONS)
- Result
- < 2 ng/L
- Benchmark
- No federal or state limit; shown for transparency
- Status
- Not detected above the reporting limit
- Sampled
- 2023-05-15 to 2024-02-12
Hexafluoropropylene oxide dimer acid (HFPO-DA) (GenX chemicals)
- Result
- < 5 ng/L
- Benchmark
- 10 ng/L federal MCL (2024)
- Status
- Not detected above the reporting limit
- Sampled
- 2023-05-15 to 2024-02-12
- Result
- < 9 µg/L
- Benchmark
- 10 µg/L EPA health reference level (screening, not a legal limit)Screening level, not a legal limit
- Status
- Not detected above the reporting limit
- Sampled
- 2023-05-15 to 2024-02-12
N-ethyl perfluorooctanesulfonamidoacetic acid (NEtFOSAA)
- Result
- < 5 ng/L
- Benchmark
- No federal or state limit; shown for transparency
- Status
- Not detected above the reporting limit
- Sampled
- 2023-05-15 to 2024-02-12
N-methyl perfluorooctanesulfonamidoacetic acid (NMeFOSAA)
- Result
- < 6 ng/L
- Benchmark
- No federal or state limit; shown for transparency
- Status
- Not detected above the reporting limit
- Sampled
- 2023-05-15 to 2024-02-12
Nonafluoro-3,6-dioxaheptanoic acid (NFDHA)
- Result
- < 20 ng/L
- Benchmark
- No federal or state limit; shown for transparency
- Status
- Not detected above the reporting limit
- Sampled
- 2023-05-15 to 2024-02-12
Perfluoro (2-ethoxyethane) sulfonic acid (PFEESA)
- Result
- < 3 ng/L
- Benchmark
- No federal or state limit; shown for transparency
- Status
- Not detected above the reporting limit
- Sampled
- 2023-05-15 to 2024-02-12
Perfluoro-3-methoxypropanoic acid (PFMPA)
- Result
- < 4 ng/L
- Benchmark
- No federal or state limit; shown for transparency
- Status
- Not detected above the reporting limit
- Sampled
- 2023-05-15 to 2024-02-12
Perfluoro-4-methoxybutanoic acid (PFMBA)
- Result
- < 3 ng/L
- Benchmark
- No federal or state limit; shown for transparency
- Status
- Not detected above the reporting limit
- Sampled
- 2023-05-15 to 2024-02-12
- Result
- < 5 ng/L
- Benchmark
- No federal or state limit; shown for transparency
- Status
- Not detected above the reporting limit
- Sampled
- 2023-05-15 to 2024-02-12
- Result
- < 3 ng/L
- Benchmark
- No federal or state limit; shown for transparency
- Status
- Not detected above the reporting limit
- Sampled
- 2023-05-15 to 2024-02-12
Perfluorododecanoic acid (PFDoA)
- Result
- < 3 ng/L
- Benchmark
- No federal or state limit; shown for transparency
- Status
- Not detected above the reporting limit
- Sampled
- 2023-05-15 to 2024-02-12
Perfluoroheptanesulfonic acid (PFHpS)
- Result
- < 3 ng/L
- Benchmark
- No federal or state limit; shown for transparency
- Status
- Not detected above the reporting limit
- Sampled
- 2023-05-15 to 2024-02-12
Perfluoroheptanoic acid (PFHpA)
- Result
- < 3 ng/L
- Benchmark
- No federal or state limit; shown for transparency
- Status
- Not detected above the reporting limit
- Sampled
- 2023-05-15 to 2024-02-12
- Result
- < 4 ng/L
- Benchmark
- 10 ng/L federal MCL (2024)
- Status
- Not detected above the reporting limit
- Sampled
- 2023-05-15 to 2024-02-12
- Result
- < 4 ng/L
- Benchmark
- 4.0 ng/L federal MCL (2024)
- Status
- Not detected above the reporting limit
- Sampled
- 2023-05-15 to 2024-02-12
Perfluorotetradecanoic acid (PFTA)
- Result
- < 8 ng/L
- Benchmark
- No federal or state limit; shown for transparency
- Status
- Not detected above the reporting limit
- Sampled
- 2023-05-15 to 2024-02-12
Perfluorotridecanoic acid (PFTrDA)
- Result
- < 7 ng/L
- Benchmark
- No federal or state limit; shown for transparency
- Status
- Not detected above the reporting limit
- Sampled
- 2023-05-15 to 2024-02-12
Perfluoroundecanoic acid (PFUnA)
- Result
- < 2 ng/L
- Benchmark
- No federal or state limit; shown for transparency
- Status
- Not detected above the reporting limit
- Sampled
- 2023-05-15 to 2024-02-12
Every value is the published result from the cited public record. A reporting limit is the lowest level the method could reliably quantify; a non-detect is not a guarantee of zero.
UCMR5 Analytical Results
UCMR5 Analytical Results: SAMMAMISH PLATEAU WATER & SEWER (WA5340900)
US EPA
State SDWIS Compliance Record
Lead & Copper Rule 90th-percentile: SAMMAMISH PLATEAU WATER & SEWER (WA5340900)
US EPA SDWIS
Methodology: how we analyze water. Prepared with AI assistance and reviewed by the PurityMap Editorial Team before publication.
Something off with your water's smell, color or taste?
Start with the hot-or-cold tap check. Where Sammamish Plateau Water & Sewer reported something related, it's shown below.
- Rotten-egg smell
- Cloudy or milky water
- Chlorine smell
- Brown or yellow water
- Metallic taste
Lead at Sammamish Plateau Water & Sewer: 1.7 µg/L (90th percentile, 2023–2025 monitoring period). Lead has no taste, so a taste neither shows nor rules it out.
ZIP codes in Sammamish
A ZIP code is a postal area, not a water service area. Your water bill names your supplier.