Oregon Water Quality Report: 6,538 Water-System Violations Mapped to 240 ZIPs
539 water systems · 240 ZIP codes · 6,538 violations
Data: EPA Safe Drinking Water Information System (SDWIS), EPA ECHO
ZipCheckup tracks EPA drinking-water compliance for 539 public water systems serving 240 ZIP codes in Oregon. The state record shows 6,538 EPA violations, 151 health-based.
City Water Quality Map: Oregon
Each circle represents a city. Size indicates population, color indicates water quality grade. Tap a circle for details.
Cities with Most Violations in Oregon
| # | City | Grade | Violations | Systems | Population | |
|---|---|---|---|---|---|---|
| 1 | Waldport | 345 | 4 | 5,251 | Details → | |
| 2 | Tidewater | 345 | 4 | 708 | Details → | |
| 3 | Seal Rock | 272 | 5 | 1,226 | Details → | |
| 4 | Salem | 219 | 16 | 279,480 | Details → | |
| 5 | Dallas | 216 | 5 | 22,977 | Details → | |
| 6 | Monmouth | 215 | 5 | 13,953 | Details → | |
| 7 | Klamath Falls | 204 | 3 | 54,963 | Details → | |
| 8 | Sheridan | 146 | 5 | 9,613 | Details → | |
| 9 | Independence | 145 | 5 | 11,384 | Details → | |
| 10 | Portland | 144 | 23 | 929,296 | Details → |
Most Common Contaminants in Oregon
| Contaminant | Category | Violations | ZIPs Affected | Health Risk |
|---|---|---|---|---|
| Surface Water Treatment Rule | Treatment Technique | 1,094 | 84 | Yes |
| Consumer Confidence Rule | Reporting | 637 | 176 | No |
| Lead and Copper Rule | Treatment Technique | 525 | 130 | Yes |
| Interim Enhanced Surface Water Treatment Rule | Treatment Technique | 524 | 72 | Yes |
| Haloacetic Acids (HAA5) | Disinfection Byproducts | 214 | 78 | Yes |
| Total Trihalomethanes (TTHM) | Disinfection Byproducts | 209 | 74 | Yes |
| Groundwater Rule | Treatment Technique | 134 | 24 | Yes |
| Coliphage | Microbiological | 128 | 47 | No |
| Nitrate | Inorganic | 85 | 56 | Yes |
| Di(2-ethylhexyl) phthalate | Organic | 70 | 47 | No |
Water Quality Overview
Oregon has 539 community water systems represented across 240 directly mapped ZIP records. The associated city records cover approximately 4,049,297 people. The available records contain 6,538 EPA violations, including 151 health-based violations.
Health-based violations account for 2% of all violations in Oregon. These violations indicate contaminant levels that may pose direct risks to human health, as opposed to monitoring or reporting failures.
Violation Breakdown
| Violation Type | Count | Percentage |
|---|---|---|
| Health-based | 151 | 2.3% |
| Monitoring/Reporting | 6,387 | 97.7% |
| Total | 6,538 | 100% |
Health-based violations are MCL, MRDL (disinfectant) and treatment-technique violations. Monitoring violations indicate failures to test or report - these do not necessarily mean unsafe water, but they mean the water was not properly verified.
Cities with Most Violations
The following cities in Oregon have the highest number of EPA violations:
| Rank | City | Violations | Water Systems | Population |
|---|---|---|---|---|
| 1 | Waldport | 345 | 4 | 5,251 |
| 2 | Tidewater | 345 | 4 | 708 |
| 3 | Seal Rock | 272 | 5 | 1,226 |
| 4 | Salem | 219 | 16 | 279,480 |
| 5 | Dallas | 216 | 5 | 22,977 |
| 6 | Monmouth | 215 | 5 | 13,953 |
| 7 | Klamath Falls | 204 | 3 | 54,963 |
| 8 | Sheridan | 146 | 5 | 9,613 |
| 9 | Independence | 145 | 5 | 11,384 |
| 10 | Portland | 144 | 23 | 929,296 |
Violation counts are cumulative across all water systems serving each city. Higher counts may reflect larger systems with more monitoring requirements, not necessarily worse water quality.
Violation Trend Over Time
Year-by-year EPA violations recorded across all water systems in Oregon:
| Year | Health-based violations |
|---|---|
| 2021 | 2 |
| 2022 | 11 |
| 2023 | 20 |
| 2024 | 42 |
| 2025 | 47 |
| 2026 | 8 |
Health-based violations have increased from 2 in 2021 to 8 in 2026. This trend warrants monitoring and may reflect expanded testing requirements rather than worsening quality.
Most Common Contaminants
The following contaminants have caused the most violations across Oregon water systems:
| Contaminant | Category | Violations | ZIPs Affected | Health-Based |
|---|---|---|---|---|
| Surface Water Treatment Rule | Treatment Technique | 1,094 | 84 | Yes |
| Consumer Confidence Rule | Reporting | 637 | 176 | No |
| Lead and Copper Rule | Treatment Technique | 525 | 130 | Yes |
| Interim Enhanced Surface Water Treatment Rule | Treatment Technique | 524 | 72 | Yes |
| Haloacetic Acids (HAA5) | Disinfection Byproducts | 214 | 78 | Yes |
| Total Trihalomethanes (TTHM) | Disinfection Byproducts | 209 | 74 | Yes |
| Nitrate | Inorganic | 85 | 56 | Yes |
| Di(2-ethylhexyl) phthalate | Organic | 70 | 47 | No |
| Tetrachloroethylene | Organic | 65 | 46 | No |
| Public Notice Rule | Reporting | 65 | 37 | No |
How to Check Your Water in Oregon
Enter your ZIP code on ZipCheckup for detailed water-system data including contaminant levels and violation history; the separate Home Safety Score is a multi-source index
Request your CCR - every water utility must provide an annual Consumer Confidence Report
Get a home test - certified kits ($20-$50) or professional lab tests ($150-$400)
Consider filtration - NSF-certified filters can address specific contaminants found in your area
EPA Enforcement
The EPA and state regulators have taken enforcement actions against water systems in Oregon. Enforcement actions range from compliance assistance to formal orders and penalties.
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Enforcement: EPA ECHO
Updated daily.
What are EPA violations?
Health-based violations are EPA violations of a Maximum Contaminant Level (MCL), a Maximum Residual Disinfectant Level (MRDL) or a required treatment technique - the enforceable standards designed to protect human health. Oregon has 151 such violations across its water systems. Not all violations cause illness; review each violation type and duration to understand possible health implications.
Understanding water quality grades
ZipCheckup grades water systems from A to F based on EPA violation history, contaminant levels, and system compliance. Grades summarize ZipCheckup's scoring inputs; review the underlying records for specific issues. Grades are calculated per ZIP code and aggregated at the city, county, and state level.
Wondering about your tap water?
Water quality varies by ZIP code. Enter yours to see contaminant data, violations, and filtration recommendations specific to your area.
Check Your ZIP Code Water Quality →Frequently Asked Questions
Is the tap water safe to drink in Oregon?
Records for 539 community water systems mapped to ZIPs in Oregon show 6,538 reported violations, including 151 health-based. Water quality varies by city and ZIP code - check your specific location for detailed results.
How many violations are on record for water systems serving Oregon?
Oregon has 6,538 EPA violations on record across 240 ZIP codes; 151 are classified as health-based violations. The remainder are monitoring or reporting violations.
Which city in Oregon has the worst water quality?
Waldport, OR has the most recorded EPA violations (345) among the cities with mapped water systems in Oregon in our data. Check your water supplier's report and test your tap water for the most accurate picture of your local water quality.
Which city in Oregon has the best water quality?
Violation records vary by water system across Oregon. Check individual city reports for details.
What contaminants are found in Oregon drinking water?
EPA regulates over 90 drinking-water contaminants nationally; water systems in Oregon monitor those applicable to each system, which can include lead, copper, nitrate, disinfection byproducts, and bacteria. The most common violations vary by region - check your ZIP code for contaminant-specific data.