Cattle Point Water District
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
- 63 people
- Connections
- 44
- Water source
- Surface water
- Based in
- Friday Harbor, WA
- County
- San Juan
- Owner
- Local government
The ZIP code it serves
The short answer
1 result is above the limit’s level with no violation recorded. The worst: Total trihalomethanes (TTHM), above the limit’s level, no violation. No health-based violations on file since 2016.
What handles itWhat was found
Copper: EPA’s file records a utility’s copper only when it exceeds the action level. The last here was 3.7 ppm, for the period ending March 31, 1998. None since is on file, so it is not counted as a current finding.
Total trihalomethanes (TTHM), haloacetic acids (HAA5), nitrate, arsenic, chromium (total) and fluoride: Washington’s own results, samples taken from Aug. 4, 2020 to Sept. 15, 2026, with EPA’s 2012 to 2019 file for earlier years.
Above the limit’s level, no violation recorded1
Total trihalomethanes (TTHM)
Forms or is added in treatment
108ppb
Highest yearly average, 2020 to 2026
2026, one sample: 4.2 ppb
Averaged by year, the highest was 108 ppb, in 2023, above EPA’s legal limit of 80 ppb. In 2026, the latest year on file, its one sample was 4.2 ppb. EPA judges this limit on running averages at each sampling point, and recorded no violation for total trihalomethanes (TTHM) at this utility since 2020. Results like these with no violation often include water sampled before treatment or blending; the utility’s annual report says what reaches the tap. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 21.7 ppb, in 2017.
What handles it
- NSF/ANSI 53 look for “Trihalomethanes (TTHM) Reduction”
- NSF/ANSI 58 look for “Trihalomethanes (TTHM) Reduction”
Below EPA’s limits2
Haloacetic acids (HAA5)
Forms or is added in treatment
14.9ppb
Highest yearly average, 2020 to 2026
2026: not found
Averaged by year, the highest was 14.9 ppb, in 2023, below EPA’s legal limit of 60 ppb. 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 yearly average of 5.5 ppb, in 2017.
What handles it
No certification claim covers this compound yet.
Nitrate
Comes from the source
0.21ppm
Highest sample; found in 1 of 6
2026: not found
The highest sample, in 2023, was 0.21 ppm, below EPA’s legal limit of 10 ppm. In 2026, the latest year on file, it wasn’t found in its one sample.
What handles it
- NSF/ANSI 58 look for “Nitrate/Nitrite Reduction”
- NSF/ANSI 53 look for “Nitrate/Nitrite (30 ppm challenge)”
4 compounds tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.
- Arsenic
- Chromium (total)
- Fluoride
- Lead
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
Claim: Trihalomethanes (TTHM) Reduction
For: Total trihalomethanes (TTHM)
Other certifiers’ wording: VOC Reduction
- NSF/ANSI 58
Claim: Trihalomethanes (TTHM) Reduction
For: Total trihalomethanes (TTHM)
At the tap, or for the whole house?
These come with the water itself, so a whole-house system certified for the same claims treats every tap and shower. A filter at the tap treats drinking water for much less. 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
Aquasana Clean Water Machine (AQ-CWM2)
Countertop
- WQA listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 401checked Oct. 9, 2026
Certified for: Total trihalomethanes (TTHM)
Brita Hub Countertop Water Filter System (87340)
Countertop
- WQA listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 401checked Oct. 9, 2026
- IAPMO listing:NSF/ANSI 53checked Oct. 9, 2026
Certified for: Total trihalomethanes (TTHM)
Ninja HydraSense Countertop Water Filtration System (WF1001)
Countertop
- IAPMO listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 401checked Oct. 9, 2026
Certified for: Total trihalomethanes (TTHM)
PUR PLUS Faucet Filtration System, Horizontal (PFM400H)
Faucet mount
- NSF listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 401checked Oct. 16, 2026
- WQA listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 401checked Oct. 16, 2026
- IAPMO listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 401checked Oct. 16, 2026
Certified for: Total trihalomethanes (TTHM)
Brita Elite Water Filter Faucet System (SAFF-100/FF-100)
Faucet mount
- WQA listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 401checked Oct. 16, 2026
Certified for: Total trihalomethanes (TTHM)
Violations since 2016
No health-based violations on file with EPA since 2016. There are 5 monitoring or reporting violations: a sample missed, late or not reported.
What this report can’t tell you
Everything else. Total trihalomethanes (TTHM), haloacetic acids (HAA5), nitrate, arsenic, chromium (total) and fluoride results here are Washington’s own from 2020 on, with EPA’s national file for 2012 to 2019. Cattle Point Water District’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 Aug. 4, 2020 to Sept. 15, 2026.
Testing your own tap
The 3 labs Washington certifies closest to the area Cattle Point Water District serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.
Exact Scientific Services, Inc.
Ferndale, WA · about 30 miles
Certified for bacteria, nitrate, lead and copper, metals, minerals and other inorganics, organic chemicals, disinfection byproducts
Eurofins DW and WW West, Washington Laboratory
Burlington, WA · about 35 miles
Certified for bacteria, nitrate, minerals and other inorganics, disinfection byproducts
Clallam County Environmental Laboratory
Port Angeles, WA · about 46 miles
Certified for bacteria, nitrate
Sources
- EPA UCMR 5 occurrence data, file of Oct. 15, 2026
- EPA SDWA bulk download (SDWIS federal data), 2026 Q3
- Washington State Department of Health, Office of Drinking Water, results from Jan. 1, 2020 to Sept. 29, 2026, read Oct. 8, 2026
- EPA Six-Year Review 4 compliance monitoring data, 2012 to 2019, file of Feb. 5, 2024
- Certified labs: Washington State Department of Ecology, Lab Accreditation Program, environmental laboratories accredited for drinking water analyses, read Oct. 10, 2026; distances from the Census 2020 ZIP code tabulation area gazetteer
- Limits and goals: each contaminant’s page, with its EPA source.
- How this page is built: methodology.
PWSID WA5342751. Rebuilt from EPA data on Oct. 18, 2026.
What to do next
- Read up on Total trihalomethanes (TTHM)What each one does to health, where it comes from, and the certification claim that addresses it.About Total trihalomethanes (TTHM)
- Get the utility’s own reportCattle Point Water District must send you a water quality report every year. It covers contaminants this page does not show.How to read it
- Test your own tap for leadYour service line, solder and fixtures decide the lead at your faucet, not the utility’s average.Lead in your water: what to do
- Compare certified filtersWhat the filters certified for these results cost over five years, cartridges included.Compare five-year costs