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KNIFE RIVER - NW TANGENT

PWS ID: OR4194328 · TANGENT, Oregon 97389

KNIFE RIVER - NW TANGENT serves 60 people in TANGENT, Oregon using Groundwater water sources. It has 77 recorded EPA violations, including 6 health-based violations. No PFAS contamination was detected in UCMR5 testing.

Water Quality Snapshot: KNIFE RIVER - NW TANGENT

KNIFE RIVER - NW TANGENT is a private-owned non-transient non-community water system that delivers drinking water to 60 residents in TANGENT, Oregon (Linn County) through 1 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 77 total violations for this system , of which 6 (8%) are health-based — meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 70 monitoring and reporting violations are on file. The most recent violation on record dates to 2012.

The most frequently cited contaminant at this system is Coliform (TCR), recorded in 20 violations (MR). This system has not yet been sampled under EPA's UCMR5 PFAS monitoring program, so no PFAS detection data is available here.

Across Oregon, EPA tracks 2,518 public water systems serving 4,005,242 people, with 206,659 cumulative violations and 20,339 health-based violations on record. About 99% of systems in the state carry at least one violation, and state-wide the average per system is 82.1 violations. KNIFE RIVER - NW TANGENT's 77 violations sit below the Oregon average. Statewide, 30 of 125 UCMR5-tested systems have reported PFAS detections (24%). All figures above are sourced directly from EPA SDWIS and UCMR5 public data releases and are updated as EPA publishes new reporting cycles.

Population Served
60
Total Violations
77
Health-Based Violations
6
Water Source
Groundwater

System Details

System Type
Non-Transient Non-Community
Owner Type
Private
Connections
1
County
Linn
School/Daycare
No
MCL Violations
6
Monitoring Violations
70
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MR 20 2009
Coliform (TCR) MCL 6 1994
Nitrate MR 5 2004
COLIPHAGE MR 2 2012
Diquat MR 2 2005
Fluoride MR 1 2002
Antimony, Total MR 1 2002
Thallium, Total MR 1 2002
Selenium MR 1 2002
Endrin MR 1 2002
BHC-GAMMA MR 1 2002
Methoxychlor MR 1 2002
Toxaphene MR 1 2002
Dalapon MR 1 2002
Endothall MR 1 2002
Glyphosate MR 1 2002
Di(2-ethylhexyl) adipate MR 1 2002
OXAMYL MR 1 2002
Simazine MR 1 2002
Di(2-ethylhexyl) phthalate MR 1 2002
Picloram MR 1 2002
Hexachlorocyclopentadiene MR 1 2002
Atrazine MR 1 2002
2,4,5-TP MR 1 2002
HEXACHLOROBENZENE MR 1 2002
Benzo(a)pyrene MR 1 2002
Pentachlorophenol MR 1 2002
1,2-DIBROMO-3-CHLOROPROPANE MR 1 2002
Chlordane MR 1 2002
Arsenic MR 1 2002

Verify This Water System

The figures above are aggregated from EPA's public databases. To verify the underlying records — or to file a complaint, request a Consumer Confidence Report, or check current monitoring status — go directly to the federal and state regulators that enforce the Safe Drinking Water Act for KNIFE RIVER - NW TANGENT.

Federal Source of Truth

EPA SDWIS — Federal Reports

EPA's Safe Drinking Water Information System (SDWIS) holds the federal compliance record for every regulated public water system. Open the system-level report by PWS ID:

View PWS ID OR4194328 on SDWIS

Source: EPA SDWIS Federal Reports Search

State Regulator

Oregon Drinking Water Authority

Oregon's primacy agency administers the Safe Drinking Water Act locally. Search EPA SDWIS for the current state contact, or use the state's public health or environment department portal.

Find OR regulator via EPA SDWIS

Violation Timeline

Each row links to the EPA SDWIS public record for verification. Cross-reference the contaminant code on EPA's federal report to see violation dates, return-to-compliance status, and enforcement actions.

Year (latest) Contaminant Category Count EPA Record
2012 COLIPHAGE MR 2 SDWIS / OR4194328 / 3028
2009 Coliform (TCR) MR 20 SDWIS / OR4194328 / 3100
2005 Diquat MR 2 SDWIS / OR4194328 / 2032
2004 Nitrate MR 5 SDWIS / OR4194328 / 1040
2002 Fluoride MR 1 SDWIS / OR4194328 / 1025
2002 Antimony, Total MR 1 SDWIS / OR4194328 / 1074
2002 Thallium, Total MR 1 SDWIS / OR4194328 / 1085
2002 Selenium MR 1 SDWIS / OR4194328 / 1045
2002 Endrin MR 1 SDWIS / OR4194328 / 2005
2002 BHC-GAMMA MR 1 SDWIS / OR4194328 / 2010
2002 Methoxychlor MR 1 SDWIS / OR4194328 / 2015
2002 Toxaphene MR 1 SDWIS / OR4194328 / 2020
2002 Dalapon MR 1 SDWIS / OR4194328 / 2031
2002 Endothall MR 1 SDWIS / OR4194328 / 2033
2002 Glyphosate MR 1 SDWIS / OR4194328 / 2034

How KNIFE RIVER - NW TANGENT Compares

Cross-reference this system's record against state averages and the federal MCL framework for context.

Metric KNIFE RIVER - NW TANGENT Oregon avg Federal benchmark
Total violations 77 82.1 SDWA compliance — any non-zero count is a recorded breach
Health-based violations 6 8.1 Indicates a contaminant exceeded a federal MCL
PFAS detection None 24% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 60 1,591 Sizing context for compliance burden

Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across 2,518 regulated public water systems in Oregon.

Federal MCL reference — Safe Drinking Water Act thresholds ▼
Contaminant Federal MCL / Action Level Note
Lead 0 mg/L (Action Level: 0.015 mg/L) Lead and Copper Rule treatment technique
Arsenic 0.010 mg/L (10 ppb) Health-based MCL since 2006
Total Coliform Treatment technique (RTCR) Indicator organism, monitoring trigger
PFOA / PFOS (PFAS) 4.0 ppt each (final 2024 rule) Compliance deadline 2029
Nitrate (as N) 10 mg/L Acute health risk for infants

Frequently Asked Questions

Is KNIFE RIVER - NW TANGENT water safe to drink? ▼
KNIFE RIVER - NW TANGENT (PWS ID: OR4194328) has 77 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 60 people using Groundwater sources.
How many people does KNIFE RIVER - NW TANGENT serve? ▼
KNIFE RIVER - NW TANGENT serves 60 people in TANGENT, Oregon. It is a Private-owned system using Groundwater water sources with 1 service connections.
What type of violations does KNIFE RIVER - NW TANGENT have? ▼
KNIFE RIVER - NW TANGENT has 77 total violations: 6 health-based violations (MCL exceedances or treatment failures), 70 monitoring/reporting violations, and 0 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in KNIFE RIVER - NW TANGENT water? ▼
No PFAS testing data is available for KNIFE RIVER - NW TANGENT under the EPA's UCMR5 monitoring program.
What water source does KNIFE RIVER - NW TANGENT use? ▼
KNIFE RIVER - NW TANGENT uses Groundwater as its primary water source. It is classified as a Non-Transient Non-Community Water System, serving the same people for at least 6 months per year.
Where does this data come from? ▼
All data comes from the EPA Safe Drinking Water Information System (SDWIS) and the UCMR5 PFAS monitoring program. SDWIS tracks compliance for all public water systems regulated under the Safe Drinking Water Act.

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Data Sources: EPA Safe Drinking Water Information System (SDWIS), Q4 2025. This data is provided for informational purposes only.

Read our methodology — how this data is sourced, computed, and verified.

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