A85/100
TUALATIN VALLEY WATER DISTRICT — Water Quality Report 2026
Serving 224,600 people · Oregon
Water Source
Purchased Surface Water
County
—
System ID
OR4100665
Violations
1
Contaminant Test Results
3 contaminants above EPA health goals
| Contaminant | Detected | Limit (MCL) | Status |
|---|---|---|---|
Copper (90th percentile) | 1.41 mg/L | 1.30 mg/L | Over Limit |
chlorate | 260.00 µg/L | — | Above Goal |
Lead (90th percentile) | 0.004 mg/L | 0.015 mg/L | Above Goal |
EPA Violation History
No violations in the past 5 years
Full EPA compliance since 2001.
Understanding violation severity
Tier 1Urgent health risk. Utility must notify all customers within 24 hours.Tier 2Important health or treatment issue. Customers notified within 30 days.Tier 3Administrative or monitoring issue. Reported in the annual water quality report.
Source: EPA Safe Drinking Water Information System (SDWIS) · Updated quarterly
Frequently Asked Questions About TUALATIN VALLEY WATER DISTRICT
Is TUALATIN VALLEY WATER DISTRICT water safe to drink?
TUALATIN VALLEY WATER DISTRICT water receives a grade of A (85/100), which is considered excellent. Out of 77 contaminants tested, 1 exceed EPA legal limits. 3 contaminant(s) exceed non-enforceable health goals. The water meets federal safety standards.
What contaminants has TUALATIN VALLEY WATER DISTRICT detected?
77 contaminants were tested in TUALATIN VALLEY WATER DISTRICT's water. Notable contaminants include Copper (90th percentile), Lead (90th percentile), chlorate. 1 exceed EPA legal limits (MCLs). 3 exceed EPA health goals (MCLGs).
Does TUALATIN VALLEY WATER DISTRICT have any EPA violations?
Yes, TUALATIN VALLEY WATER DISTRICT has 1 EPA violation(s) on record, with the most recent in 2001. Violation types include MR.
How many people does TUALATIN VALLEY WATER DISTRICT serve?
TUALATIN VALLEY WATER DISTRICT serves approximately 224,600 people, Oregon.
What type of water does TUALATIN VALLEY WATER DISTRICT provide?
TUALATIN VALLEY WATER DISTRICT sources its water from purchased surface water. Surface water comes from rivers, lakes, or reservoirs and typically requires more extensive treatment. The utility's system ID is OR4100665.
How does TUALATIN VALLEY WATER DISTRICT compare to other utilities in Oregon?
TUALATIN VALLEY WATER DISTRICT scores 85/100 with a grade of A (excellent). This places it among the higher-performing utilities in the state. Visit our Oregon state page for a full comparison of water systems.