Lower Siletz Water System
What EPA’s and CDC’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
- 165 people
- Connections
- 159
- Water source
- Surface water bought from another system
- Based in
- Lincoln City, OR
- County
- Lincoln
- Owner
- Private
The ZIP code it serves
The short answer
Nothing in EPA’s and CDC’s records for this utility is above a health goal. That covers nitrate, arsenic and other regulated chemicals, plus lead and copper, not everything. No health-based violations on file since 2016.
What was found
Haloacetic acids (HAA5), total trihalomethanes (TTHM), nitrate, arsenic and uranium: Oregon’s yearly averages per water system, as CDC’s Environmental Public Health Tracking Network publishes them, 2020 to 2023, with EPA’s 2012 to 2019 file for earlier years.
Below EPA’s limits3
Haloacetic acids (HAA5)
Forms or is added in treatment
15.7ppb
Highest yearly average, 2020 to 2023
2023 average: 11.2 ppb
Averaged by year, the highest was 15.7 ppb, in 2022, below EPA’s legal limit of 60 ppb. In 2023, the latest year on file, it averaged 11.2 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 19.6 ppb, in 2019.
What handles it
No certification claim covers this compound yet.
Total trihalomethanes (TTHM)
Forms or is added in treatment
17.2ppb
Highest yearly average, 2020 to 2023
2023 average: 15.6 ppb
Averaged by year, the highest was 17.2 ppb, in 2021, below EPA’s legal limit of 80 ppb. In 2023, the latest year on file, it averaged 15.6 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 24.6 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
0.42ppm
Highest yearly average, 2020 to 2023
Averaged by year, the highest was 0.42 ppm, in 2023, below EPA’s legal limit of 10 ppm. That was also the latest year on file.
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
- Lead
- Uranium
Violations since 2016
No health-based violations on file with EPA since 2016. There are 7 monitoring or reporting violations: a sample missed, late or not reported.
What this report can’t tell you
Everything else. Haloacetic acids (HAA5), total trihalomethanes (TTHM), nitrate, arsenic and uranium results here are Oregon’s yearly averages as CDC publishes them, from 2020 on, with EPA’s national file for 2012 to 2019. Lower Siletz Water System’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; CDC’s yearly averages for Oregon cover 2020 to 2023.
Testing your own tap
The 3 labs Oregon certifies closest to the area Lower Siletz Water System serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.
Eurofins Corvallis
Corvallis, OR · about 40 miles
Certified for bacteria, nitrate
Waterlab Corp.
Salem, OR · about 45 miles
Certified for bacteria, nitrate, lead and copper, metals, minerals and other inorganics
U.S. Region 9 Lab - Corvallis, OR
Corvallis, OR · about 45 miles
Certified for nitrate, lead and copper, metals, minerals and other inorganics, organic chemicals, PFAS
Oregon State University Extension Well Water Program: Nitrate screening of well water at many of its groundwater education events. The screening is free. Water Testing Guidance for Private Wells, OSU Well Water Program.
All 91 certified labs for OregonSources
- EPA UCMR 5 occurrence data, file of Oct. 15, 2026
- EPA SDWA bulk download (SDWIS federal data), 2026 Q3
- CDC Environmental Public Health Tracking Network, yearly averages Oregon supplied to CDC, 2020 to 2023, read Oct. 8, 2026. TapBuff’s comparisons with EPA’s limits are its own, not CDC’s or Oregon’s.
- EPA Six-Year Review 4 compliance monitoring data, 2012 to 2019, file of Feb. 5, 2024
- Certified labs: Oregon Environmental Laboratory Accreditation Program, drinking water labs, as listed in TNI LAMS, read Oct. 13, 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 OR4101428. Rebuilt from EPA data on Oct. 18, 2026.
What to do next
- Nothing here is above a health goalIn EPA’s and CDC’s records for this utility. They don’t cover everything, which is why the next step matters.Every contaminant TapBuff tracks
- Get the utility’s own reportLower Siletz Water System 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
- Decide if you want a filter at allA filter for taste or chlorine is a preference, not a need. The standards say what each kind can do.NSF/ANSI standards, decoded