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Knoll Terrace Subdivision

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
221 people
Connections
134
Water source
Surface water bought from another system
Based in
Canyonville, OR
County
Douglas
Owner
Private

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) and nitrate: Oregon’s yearly averages per water system, as CDC’s Environmental Public Health Tracking Network publishes them, 2023.

Below EPA’s limits3

Haloacetic acids (HAA5)

Forms or is added in treatment

Below EPA’s limits

45.7ppb

Highest yearly average, 2023

Averaged by year, the highest was 45.7 ppb, in 2023, below EPA’s legal limit of 60 ppb. That is the only year on file.

What handles it

No certification claim covers this compound yet.

Total trihalomethanes (TTHM)

Forms or is added in treatment

Below EPA’s limits

38.3ppb

Highest yearly average, 2023

Averaged by year, the highest was 38.3 ppb, in 2023, below EPA’s legal limit of 80 ppb. That is the only year on file.

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

1.6ppm

Highest yearly average, 2023

Averaged by year, the highest was 1.6 ppm, in 2023, below EPA’s legal limit of 10 ppm. That is the only year on file.

What handles it

  • NSF/ANSI 58 look for “Nitrate/Nitrite Reduction”
  • NSF/ANSI 53 look for “Nitrate/Nitrite (30 ppm challenge)”
One compound tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.
  • Lead

Violations since 2016

No health-based violations on file with EPA since 2016. There are 4 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) and nitrate results here are Oregon’s yearly averages as CDC publishes them, from 2023 on, with EPA’s national file for 2012 to 2019. Knoll Terrace Subdivision’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 2023.

Testing your own tap

Knoll Terrace Subdivision’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 Oregon certifies.

No lab Oregon certifies is within 75 miles of the area Knoll Terrace Subdivision serves on the state’s list. Some take samples by mail; the state’s page lists them all.

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 Oregon

Sources

PWSID OR4101560. Rebuilt from EPA data on Oct. 18, 2026.

Also in Douglas County

All Oregon utilities

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