Martin Creek Community Assn
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
- 109 people
- Connections
- 44
- Water source
- Groundwater
- Based in
- Tonasket, WA
- County
- Ferry
- Owner
- Private
The ZIP code it serves
The short answer
1 result is above EPA’s legal limit. The worst: Fluoride, above the legal limit. 11 health-based violations since 2016.
What handles itWhat was found
Fluoride and nitrate: Washington’s own results, samples taken from Feb. 12, 2020 to May 5, 2026, with EPA’s 2012 to 2019 file for earlier years.
Arsenic and chromium (total): EPA’s compliance monitoring file, samples taken from May 21, 2012 to April 10, 2019. Newer results are in the utility’s annual water quality report.
Above the legal limit1
Fluoride
Forms or is added in treatment
5.5ppm
Highest yearly average, 2020 to 2026
2026 average: 5.1 ppm
Averaged by year, the highest was 5.5 ppm, in 2024, above EPA’s legal limit of 4.0 ppm. Its highest single sample was 6.1 ppm. In 2026, the latest year on file, its two samples averaged 5.1 ppm, above the limit. EPA recorded violations for fluoride at this utility in 2023, 2024, 2025 and 2026. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 4.5 ppm, in 2015.
What handles it
- NSF/ANSI 58 look for “Fluoride Reduction”
- NSF/ANSI 53 look for “Fluoride”
Below EPA’s limits1
Nitrate
Comes from the source
0.18ppm
Highest sample; found in 1 of 19
2026 average: 0.09 ppm
The highest sample, in 2026, was 0.18 ppm, below EPA’s legal limit of 10 ppm. That was also the latest year on file, and its two samples averaged 0.09 ppm.
What handles it
- NSF/ANSI 58 look for “Nitrate/Nitrite Reduction”
- NSF/ANSI 53 look for “Nitrate/Nitrite (30 ppm challenge)”
3 compounds tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.
- Arsenic
- Chromium (total)
- 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: Fluoride
For: Fluoride
- NSF/ANSI 58
Claim: Fluoride Reduction
For: Fluoride
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
Under-sink reverse osmosis
- IAPMO listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 58checked Oct. 4, 2026
Certified for: Fluoride
Under-sink reverse osmosis
- IAPMO listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 58checked Oct. 9, 2026
Certified for: Fluoride
Aquasana SmartFlow Reverse Osmosis (AQ-SFRO2)
Under-sink reverse osmosis
- WQA listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 58NSF/ANSI 401checked Oct. 9, 2026
Certified for: Fluoride
Brondell Capella RC250 Reverse Osmosis System
Under-sink reverse osmosis
- WQA listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 58NSF/ANSI 401checked Oct. 9, 2026
Certified for: Fluoride
Violations since 2016
| Contaminant or rule | Type | Period | Measured | Status |
|---|---|---|---|---|
| Fluoride | A sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single Sample | April 1, 2026 to June 30, 2026 | 5.3 MG/L | Archived |
| Fluoride | A sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single Sample | Jan. 1, 2026 to March 31, 2026 | 5.2 MG/L | Archived |
| Fluoride | A sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single Sample | Oct. 1, 2025 to Dec. 31, 2025 | 5.5 MG/L | Archived |
| Fluoride | A sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single Sample | July 1, 2025 to Sept. 30, 2025 | 5.5 MG/L | Archived |
| Fluoride | A sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single Sample | April 1, 2025 to June 30, 2025 | 5.7 MG/L | Archived |
| Fluoride | A sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single Sample | Jan. 1, 2025 to March 31, 2025 | 5.7 MG/L | Archived |
| Fluoride | A sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single Sample | Oct. 1, 2024 to Dec. 31, 2024 | 5.5 MG/L | Archived |
| Fluoride | A sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single Sample | July 1, 2024 to Sept. 30, 2024 | 5.4 MG/L | Archived |
| Fluoride | A sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single Sample | April 1, 2024 to June 30, 2024 | 5.2 MG/L | Archived |
| Fluoride | A sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single Sample | Jan. 1, 2024 to March 31, 2024 | 5.0 MG/L | Archived |
| Fluoride | A sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single Sample | Oct. 1, 2023 to Dec. 31, 2023 | 4.5 MG/L | Archived |
| Health-based violations only. Resolved and archived mean the utility returned to compliance or the state closed the record. | ||||
What this report can’t tell you
Everything else. Fluoride and nitrate results here are Washington’s own from 2020 on, with EPA’s national file for 2012 to 2019. Arsenic and chromium (total) come from EPA’s file alone, which ends in 2019. Martin Creek Community Assn’s own annual report, which it must send you every year, has newer results for those and 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 Feb. 12, 2020 to May 5, 2026; EPA’s compliance samples are from May 21, 2012 to April 10, 2019.
Testing your own tap
The 3 labs Washington certifies closest to the area Martin Creek Community Assn serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.
Lincoln County Environmental Health Lab
Davenport, WA · about 51 miles
Certified for bacteria
Anatek Labs, Inc - Spokane
Spokane, WA · about 63 miles
Certified for bacteria, nitrate, lead and copper, metals, minerals and other inorganics, organic chemicals, disinfection byproducts, radioactivity
Tshimakain Creek Laboratories
Spokane Valley, WA · about 64 miles
Certified for bacteria, nitrate, minerals and other inorganics
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 WA5351877. Rebuilt from EPA data on Oct. 18, 2026.
What to do next
- Read up on FluorideWhat each one does to health, where it comes from, and the certification claim that addresses it.About Fluoride
- Get the utility’s own reportMartin Creek Community Assn must send you a water quality report every year. It covers contaminants this page does not show, and has newer results than EPA’s national file for the ones here that come from it.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