Tualatin Valley Water District
EPA ID: OR4100665 · 224,600 people served · 16 ZIP codes
The five-year EPA compliance file for Tualatin Valley Water District contains 3 violations, each documented and subsequently closed — the utility now operates in full compliance and continues to supply approximately 224,600 residents with water meeting current federal standards, including both health-based and monitoring requirements.
Data: EPA SDWIS Last verified: 2026-04-02
Compliance Trajectory
Worsening · Risk tier: High · 95% chance of violation in next 12 months
Violations went from 1 (2022) to 1 (2025). The pattern suggests growing compliance challenges.
Service Area Map
Coverage area for Tualatin Valley Water District Source: EPA SDWIS service area boundaries.
Service area boundary — Grade B
Service Area Demographics
The Tualatin Valley Water District serves a community with a median household income of $105,999 and an estimated 474,498 residents across its service area. Approximately 51% of housing stock was built before 1986, which increases the likelihood of lead service lines and older plumbing.
🌊 Where Does Your Water Come From?
Tualatin Valley Water District's water is drawn from rivers, lakes, or reservoirs. Surface water sources are more exposed to agricultural runoff, stormwater, and upstream discharges, but they typically receive more intensive treatment before reaching your tap.
About 2% of homes in Washington County, Oregon rely on private wells rather than public water systems. Private well owners are responsible for their own water testing and treatment.
Infrastructure Risk
Detected Contaminants
How Tualatin Valley Water District compares to EPA limits
What This Means For You
Surface Water Treatment Rule at 2 mg/L exceeds the EPA maximum of mg/L.
Stage 1 DBP Rule at 1 mg/L exceeds the EPA maximum of mg/L.
Comparable Water Systems
Similar-sized systems in Oregon
Estimated Remediation Costs
Average estimated costs across ZIP codes served by this system
Based on national averages for common remediation projects. Actual costs vary by property. Only issues flagged by EPA, FEMA, or state data for each ZIP code are included.
System Overview
Tualatin Valley Water District (EPA ID: OR4100665) is a community water system in Oregon that serves approximately 224,600 people from surface water sources.
This system provides water to 16 ZIP codes across 4 communities.
Average Home Safety Score: B (77/100)
Based on water quality violations, lead levels, and radon risk across all ZIP codes served by this system.
Violation History
Recent Violations
| Date | Contaminant | Type | Status |
|---|---|---|---|
| January 1, 2025 | Stage 1 DBP Rule | Monitoring | Resolved |
| October 1, 2024 | Surface Water Treatment Rule | Monitoring | Resolved |
| July 1, 2024 | Surface Water Treatment Rule | Monitoring | Resolved |
Contaminants Detected
The following contaminants have been flagged in EPA records for this water system:
| Contaminant | Category | Violations | Health-Based |
|---|---|---|---|
| Surface Water Treatment Rule | Treatment Failure | 2 | No |
| Stage 1 DBP Rule | Treatment Failure | 1 | No |
Lead & Copper
EPA Lead and Copper Rule sampling data for ZIP codes served by this system:
| ZIP Code | Lead Level | Exceeds Limit | Sample Date |
|---|---|---|---|
| 97003 | 0.0045 mg/L | No | N/A |
| 97005 | 0.0045 mg/L | No | N/A |
| 97006 | 0.0045 mg/L | No | N/A |
| 97007 | 0.0045 mg/L | No | N/A |
| 97008 | 0.0045 mg/L | No | N/A |
| 97075 | 0.0045 mg/L | No | N/A |
| 97076 | 0.0045 mg/L | No | N/A |
| 97077 | 0.0045 mg/L | No | N/A |
Radon Risk in Service Area
Dominant radon zone for ZIP codes served by this system: Zone 2 (Moderate Risk)
The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.
Need help with your water quality?
Typical cost: Water test: typically $20–$50 (DIY kit) · Professional inspection: $150–$400
Find the Right Water FilterFree tip: Let cold water run for 2 minutes before drinking — this helps flush lead from your pipes.
ZIP Codes Served
Coverage: 13 ZIP codes confirmed via EPA Community Water System Service Area Boundaries v3 plus 3 additional ZIPs inferred from SDWIS registry data. The EPA-confirmed set is the most reliable; SDWIS-inferred entries may be narrower than the real deployment area.
- 97003 — Beaverton
- 97005 — Beaverton
- 97006 — Beaverton
- 97007 — Beaverton
- 97008 — Beaverton
- 97075 — Beaverton
- 97076 — Beaverton
- 97077 — Beaverton
- 97078 — First Consumers Nat Bank
- 97123 — Hillsboro
- 97124 — Hillsboro
- 97210 — Portland
- 97223 — Portland
- 97225 — Portland
- 97229 — Portland
- 97231 — Portland
Data Sources
This report uses public data from the EPA Safe Drinking Water Information System (SDWIS). View the full compliance record for Tualatin Valley Water District (OR4100665) on EPA.gov.
Frequently Asked Questions
Is Tualatin Valley Water District water safe to drink?
Tualatin Valley Water District has only monitoring/reporting violations, which are procedural in nature. The system meets federal health-based standards.
How many people does Tualatin Valley Water District serve?
Tualatin Valley Water District serves approximately 224,600 people across 16 ZIP codes in Oregon.
Where does Tualatin Valley Water District get its water?
The primary water source is surface water.
Contact Your Water Utility
Public-record contact information for the water utility serving this system. Use these channels to request water quality reports, ask about service, or report issues directly.
Contact information from City of Tualatin Consumer Confidence Report.
ZipCheckup is not affiliated with this water utility, does not act as its agent, and does not provide customer support for it. Contact details shown are public-record information from CCR filings. For service issues, contact the utility directly using the information above.
Water Source & Treatment
Where this water originates and how it's treated before reaching your tap.
Source: City of Tualatin Consumer Confidence Report.
ZipCheckup is not affiliated with this water utility. Treatment and source data are sourced from the utility's published CCR filings.
For the Bull Run, the only contaminants of concern are naturally occurring microorganisms, such as Giardia, Cryptosporidium, fecal coliform bacteria, and total coliform bacteria. The Columbia South Shore Well Field is beneath homes and businesses with a variety of potential contaminant sources.
Treatment regime
How this utility classifies its treatment process and what each reported treatment chemical does.
Treatment chemicals and what each one does
Chemical names are reported verbatim by the utility. Purpose categories are ZipCheckup annotations based on standard drinking-water treatment practice.
Watershed exposure sources reported
Land-use and natural conditions identified in the utility's source-water assessment as potential contamination sources upstream of treatment.
Treatment classification and chemical list sourced from City of Tualatin Consumer Confidence Report.
Treatment intensity is a ZipCheckup-derived classification based on the chemicals and processes the utility reports. Chemicals and contamination sources are taken verbatim from the utility's CCR filing. Routine federal monitoring and contaminant testing shown elsewhere on this page determine whether the water meets safety standards, not the treatment classification.
Federal UCMR5 PFAS Monitoring: Tested Clean
This water system was tested under the federal EPA Unregulated Contaminant Monitoring Rule (UCMR5). No PFAS compounds were detected.
Current MCL reflects the lowest state-enforceable limit (NYS 10 ppt for PFOA/PFOS, effective August 2020). The federal final MCL of 4 ppt for PFOA/PFOS (EPA April 2024 rule) is not enforceable until April 2029. Detections above 4 ppt but below 10 ppt are below current MCL but above the future federal limit.
Source: U.S. EPA UCMR5 (Unregulated Contaminant Monitoring Rule, 5th cycle) — per-system federal sampling, 2023–2025. EPA UCMR5 monitoring program →
Lead Service Line Replacement Tracker
This water utility's lead service line (LSL) replacement program is tracked from public Consumer Confidence Report filings. Email signup notifies subscribers when the utility files an updated replacement plan or progress milestone.
City of Tualatin
ZipCheckup is not affiliated with this water utility. LSL replacement-program data is sourced from public CCR filings published by the utility. Subscription notifications are based on automated parsing of subsequent CCR releases.
Learn more about Lead and Copper Rule replacement requirements →
Lead Service Line Inventory
Service line breakdown reported under the federal Lead and Copper Rule Improvements (LCRI) inventory requirement:
This system reports zero confirmed lead service lines in its inventory. Unknown-material counts may still warrant verification.
Federal LCRI rule (effective October 2024) requires every public water system to inventory its service lines and complete lead-line replacement within 10 years.
Source: EPA SDWIS Federal Service Line Inventory (Phase 2) · Submitted 2026
ZipCheckup is not affiliated with the utility or state agency. Inventory figures render verbatim from the public LCRI submission cited above; ZipCheckup does not perform inspections or replacements.
Notable events and violations
This section summarizes events the utility chose to disclose in its most recent Consumer Confidence Report, plus any federal compliance violations the utility recorded against itself. Both lists are utility-authored — ZipCheckup does not audit, judge, or reorder them.
Federal compliance violations on record
These entries are taken verbatim from the utility's CCR violations section. EPA defines four broad violation categories: Maximum Contaminant Level (MCL), Treatment Technique (TT), Monitoring & Reporting (M&R), and Public Notification (PN).
-
monitoring · Coliform BacteriaJuly 2022
Portland Water Bureau did not complete all monitoring or testing for coliform bacteria, testing 238 samples instead of the required 240 samples per month.
Violations record from City of Tualatin Consumer Confidence Report.
Notable events from the utility's CCR
These bullet entries are the utility's own narration of operational, regulatory, or infrastructure events during the reporting period.
- Portland Water Bureau brought Improved Corrosion Control Treatment online at Portland's Lusted Hill Facility in April 2022.
- Tualatin conducted three rounds of demonstration sampling for lead and copper in Fall 2022, Spring 2023, and Fall 2023.
ZipCheckup note: items above reflect what the utility published in its most recent CCR. Federal violation records are also tracked separately by the EPA Safe Drinking Water Information System (SDWIS) — the SDWIS record is the authoritative federal source for any specific regulatory action.
How Water Systems Appear in Rankings
Water systems are evaluated by violation history, contaminant detections, and service population. Larger systems with more service connections appear in more rankings.
- #10 / 50 Highest Exposure Burden (Oregon)
Frequently Asked Questions
What You Can Do
Test your water
Home test kits can detect lead, bacteria, and other contaminants at your tap. Find the right filter →
Check your specific ZIP code
Water quality can vary within a system. View nearest ZIP report →
Contact your utility
Tualatin Valley Water District (EPA ID: OR4100665) — request the latest Consumer Confidence Report or ask about specific contaminants.