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Sunset West Water Association

What EPA’s and Washington’s records show in this utility’s water: nitrate, arsenic and other regulated chemicals; lead and copper; and violations since 2016, with the certification that handles each result.

Serves
62 people
Connections
35
Water source
Groundwater
Based in
MT Vernon, WA
County
Skagit
Owner
Private
Hardness
Hard
The ZIP code it serves

98221

The short answer

2 results are above the health goal. The worst: Arsenic, above the health goal. No health-based violations on file since 2016.

What handles it

What was found

Lead and copper: EPA SDWIS monitoring periods ending 2003 to 2024.

Arsenic, total trihalomethanes (TTHM), nitrate, haloacetic acids (HAA5), chromium (total) and fluoride: Washington’s own results, samples taken from Sept. 8, 2020 to July 9, 2026, with EPA’s 2012 to 2019 file for earlier years.

Above the health goal2

Arsenic

Comes from the source

Above the health goal

1.1ppb

Highest yearly average, 2025

Averaged by year, the highest was 1.1 ppb, in 2025: below EPA’s legal limit of 10 ppb, but above its health goal of zero. That is the only year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 1.0 ppb, in 2016.

What handles it

  • NSF/ANSI 58 look for “Arsenic (Pentavalent)<=50 ppb Reduction”
  • NSF/ANSI 53 look for “Arsenic (Pentavalent)<=50 ppb Reduction”

Lead

Comes from pipes, often your own

Above the health goal

0.7ppb

90th percentile, 2022 to 2024

In the latest period, 9 in 10 homes sampled were at or below 0.7 ppb, below EPA’s action level of 15 ppb. The action level drops to 10 ppb on Nov. 1, 2027. EPA’s health goal for lead is zero.

What handles it

Below EPA’s limits5

Total trihalomethanes (TTHM)

Forms or is added in treatment

Below EPA’s limits

19.5ppb

Highest yearly average, 2020 to 2026

2026, one sample: 8.9 ppb

Averaged by year, the highest was 19.5 ppb, in 2020, below EPA’s legal limit of 80 ppb. In 2026, the latest year on file, its one sample was 8.9 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 28.9 ppb, in 2019.

What handles it

  • NSF/ANSI 53 look for “Trihalomethanes (TTHM) Reduction”
  • NSF/ANSI 58 look for “Trihalomethanes (TTHM) Reduction”

Nitrate

Comes from the source

Below EPA’s limits

2.3ppm

Highest sample; found in 12 of 13

2026: not found

The highest sample, in 2020, was 2.3 ppm, below EPA’s legal limit of 10 ppm. In 2026, the latest year on file, it wasn’t found in its one sample. Earlier, from 2012 to 2019, EPA’s file shows a highest sample of 2.7 ppm, in 2012.

What handles it

  • NSF/ANSI 58 look for “Nitrate/Nitrite Reduction”
  • NSF/ANSI 53 look for “Nitrate/Nitrite (30 ppm challenge)”

Haloacetic acids (HAA5)

Forms or is added in treatment

Below EPA’s limits

3.7ppb

Highest yearly average, 2020 to 2026

2026, one sample: 2.9 ppb

Averaged by year, the highest was 3.7 ppb, in 2023, below EPA’s legal limit of 60 ppb. In 2026, the latest year on file, its one sample was 2.9 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 4.6 ppb, in 2016.

What handles it

No certification claim covers this compound yet.

Chromium (total)

Comes from the source

Below EPA’s limits

5.4ppb

Highest yearly average, 2025

Averaged by year, the highest was 5.4 ppb, in 2025, below EPA’s legal limit of 100 ppb. That is the only year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 7.0 ppb, in 2016.

What handles it

Fluoride

Forms or is added in treatment

Below EPA’s limits

0.12ppm

Highest yearly average, 2025

Averaged by year, the highest was 0.12 ppm, in 2025, below EPA’s legal limit of 4.0 ppm. That is the only year on file.

What handles it

What handles it

A certification covers specific claims, not a whole standard. Look for these claims on the certifier’s listing, not the box. Wording varies a little: NSF writes “Lead Reduction,” WQA just “Lead.”

  • NSF/ANSI 53

    Claims: Arsenic (Pentavalent)<=50 ppb Reduction, Lead Reduction

    For: Arsenic, Lead

    Other certifiers’ wording: Arsenic (III) (50 ppb influent level)

  • NSF/ANSI 58

    Claims: Arsenic (Pentavalent)<=50 ppb Reduction, Lead Reduction

    For: Arsenic, Lead

    Other certifiers’ wording: Arsenic (Pentavalent)<=300 ppb Reduction; Arsenic (V) (300 ppb influent level)

At the tap, or for the whole house?

Lead and copper usually come from pipes and fixtures inside or near your home. A whole-house system sits where water enters, so it cannot catch what your own plumbing adds after it. For those, the filter that counts is the one at the tap. How whole-house systems compare.

Filters with those claims on a certifier’s listing

Disclosure: TapBuff earns a commission if you buy through some links on this page. It does not change which standard or filter we name. As an Amazon Associate, TapBuff earns from qualifying purchases. How TapBuff makes money

Compare five-year costs

The best reverse osmosis systems, ranked

The best water filters for lead, ranked

Hardness

Hard, 166 mg/L (9.7 grains per gallon), at its one sampling point, in 2025.

Hardness is calcium and magnesium. EPA sets no limit for it: it shows up as scale on fixtures and in water heaters, and as soap that won’t lather. USGS calls water above 60 mg/L moderately hard, above 120 hard and above 180 very hard.

Softeners compared at 9.7 grains per gallon, salt includedSoftener or salt-free conditioner?Washington water hardness, utility by utility

Violations since 2016

No health-based violations on file with EPA since 2016. There is 1 monitoring or reporting violation: a sample missed, late or not reported.

What this report can’t tell you

  • Everything else. Arsenic, total trihalomethanes (TTHM), nitrate, haloacetic acids (HAA5), chromium (total) and fluoride results here are Washington’s own from 2020 on, with EPA’s national file for 2012 to 2019. Sunset West Water Association’s own annual report, which it must send you every year, has the contaminants this page does not show.

  • Your own plumbing. Lead results are the 90th percentile across homes the utility samples. Your home’s service line, solder and fixtures decide yours. A certified lab test is the only way to know.

  • What it means for your health. This page reports what the records show and EPA’s limits and goals; it is not medical advice. If you are worried about a health effect, talk to a doctor or your local health department.

  • Anything after the latest data. SDWIS data is from 2026 Q3; UCMR 5 didn’t sample this utility; Washington’s results run from Sept. 8, 2020 to July 9, 2026.

Testing your own tap

Sunset West Water Association’s results are for the water it sends out. What your own service line, solder and fixtures add shows up only in a test of your tap, by a lab Washington certifies.

The 3 labs Washington certifies closest to the area Sunset West Water Association serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.

  • Eurofins DW and WW West, Washington Laboratory

    Burlington, WA · about 14 miles

    Certified for bacteria, nitrate, minerals and other inorganics, disinfection byproducts

    (360) 757-1400

  • Exact Scientific Services, Inc.

    Ferndale, WA · about 25 miles

    Certified for bacteria, nitrate, lead and copper, metals, minerals and other inorganics, organic chemicals, disinfection byproducts

    (360) 733-1205

  • Freshwater Analytical Labs, LLC

    Arlington, WA · about 38 miles

    Certified for bacteria

    (360) 913-7542

All 84 certified labs for Washington

Sources

PWSID WA5386205. Rebuilt from EPA data on Oct. 18, 2026.

Also in Skagit County

All Washington utilities

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