Water Quality in The Dalles, OR: 10 Violations — Grade B
Grade B · Score 82/100 · 5 water systems · Updated 2026-05-03
The Dalles's water is mostly safe. Minor violations exist but are primarily monitoring-related.
Data: EPA Safe Drinking Water Information System (SDWIS) Last verified: 2026-05-03
The Dalles, OR has 10 violations in the EPA compliance history — breakdown below.
Water Quality by ZIP Code in The Dalles
Water quality varies across The Dalles's 1 ZIP codes. Check your specific ZIP for detailed contaminant data.
| ZIP Code | Grade | Score | Violations | Health | |
|---|---|---|---|---|---|
| 97058 | B | 82 | 10 | 1 | View report → |
Water Quality Overview
The Dalles, Oregon receives a water quality grade of B with an overall score of 82 out of 100, based on EPA compliance data from the Safe Drinking Water Information System (SDWIS).
The 5 water systems serving The Dalles have accumulated 10 EPA violations, including 1 health-based violation. These violations are tracked across 1 ZIP codes serving approximately 18,230 people.
What Grade B Means
A grade of B indicates good compliance with EPA drinking water standards. While not perfect, The Dalles's water systems meet the vast majority of federal requirements. Minor violations may exist but typically relate to monitoring or reporting rather than health-based standards.
Lead Levels
The average 90th percentile lead level across The Dalles water systems is 0.0008 mg/L — within EPA limits. No ZIP codes exceed the EPA lead action level.
With 75% of homes built before 1986, The Dalles has a higher-than-average risk of lead from older plumbing. Lead solder was banned in 1986, and homes built before this date may have lead in pipes, solder joints, or fixtures.
Radon Risk
The Dalles is in EPA Radon Zone 2 (Moderate risk). Testing is recommended, especially for homes with basements or ground-level living spaces.
Water Systems Serving The Dalles
The Dalles is served by 5 community water systems regulated under the Safe Drinking Water Act. These systems collectively serve approximately 18,230 people across 1 ZIP codes.
Each water system is identified by a Public Water System ID (PWSID) and is required to:
- Test for over 90 regulated contaminants on a regular schedule
- Report results to the EPA and state regulators
- Issue an annual Consumer Confidence Report (CCR) to all customers
- Take corrective action when violations occur
The EPA has taken 10 enforcement actions against water systems serving The Dalles. Enforcement actions range from informal compliance assistance to formal orders and penalties.
How to Check Your Water in The Dalles
Enter your ZIP code on ZipCheckup to see your specific water system data, including contaminant levels, violation history, and safety scores
Request your CCR — your water utility must provide an annual Consumer Confidence Report with detailed test results for all monitored contaminants
Get a home test — certified kits cost $20–$50 and test for lead, bacteria, and common contaminants. Professional lab tests ($150–$400) cover a broader panel
Consider filtration — NSF-certified filters can remove specific contaminants. Reverse osmosis removes the broadest range; activated carbon is effective for chlorine and many organics
Check for advisories — monitor your local utility website and local news for boil water advisories or system alerts
Contaminants Detected in The Dalles Water Systems
The following contaminants have been detected or caused violations across The Dalles's water systems:
| Contaminant | Category | MCL | Violations | ZIPs Affected | Health-Based |
|---|---|---|---|---|---|
| E. coli | Microbiological | N/A | 1 | 1 | No |
| Fecal Coliform | Microbiological | N/A | 1 | 1 | No |
| Stage 1 DBP Rule | Treatment Technique | N/A | 1 | 1 | No |
| Gross Alpha | Radionuclides | 15 pCi/L | 1 | 1 | No |
| Total Trihalomethanes (TTHM) | Disinfection Byproducts | 0.08 mg/L | 1 | 1 | No |
| Total Coliform | Microbiological | N/A | 1 | 1 | No |
| Surface Water Treatment Rule | Treatment Technique | N/A | 1 | 1 | No |
MCL = Maximum Contaminant Level (EPA enforceable standard). Health-based violations indicate levels that may pose direct health risks.
EPA Enforcement History
The EPA and state regulators have taken 10 enforcement actions against water systems serving The Dalles. Recent actions:
| Date | Action Type |
|---|---|
| 2025-03-12 | State Informal Action |
| 2024-09-23 | State Order Extension |
| 2024-07-02 | State Order Extension |
| 2024-01-05 | State Order Extension |
| 2023-09-07 | State Order Extension |
| 2023-07-03 | State Order Extension |
| 2023-06-30 | State Informal Action |
| 2023-06-19 | State Order Extension |
| 2022-10-05 | State Order Extension |
| 2022-07-18 | State Informal Enforcement |
Enforcement actions range from informal compliance assistance to formal orders and penalties. The most recent action was on 2025-03-12.
The Dalles vs. Nearby Oregon Cities
How The Dalles's water quality compares to similar cities in Oregon:
| City | Grade | Violations | Systems | Population |
|---|---|---|---|---|
| The Dalles | B | 10 | 5 | 18,230 |
| Dallas | A | 14 | 1 | 17,911 |
| Crabtree | C | 0 | 1 | 18,945 |
| Pendleton | B | 6 | 5 | 17,421 |
Common Questions About The Dalles Water
These are the most common questions residents search for about water quality in The Dalles, Oregon:
Is The Dalles water hard or soft? Water hardness varies by source. The Dalles's 5 water systems use multiple sources. Check your ZIP code report for specific hardness data.
Can I drink The Dalles tap water? The Dalles's water receives a grade of B (82/100). There are 1 health-based violations — consider filtration.
What is the best water filter for The Dalles? A NSF/ANSI 53-certified filter for lead removal is a good general choice. See our Water Filter Matcher for personalized recommendations.
The Dalles vs. Oregon Average
Understanding how The Dalles compares to the broader Oregon average helps contextualize your local water quality. Factors like water source, treatment methods, and infrastructure age all contribute to differences between cities in the same state.
To see how individual neighborhoods compare, check the ZIP code reports below — water quality can vary significantly even within The Dalles.
ZIP Codes in The Dalles
The Dalles spans 1 ZIP code. The ZIP with the lowest water quality score is 97058. Each ZIP code has its own water quality profile based on the specific water system serving that area. Check each ZIP code for detailed contaminant data, violation history, and system information.
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Lead/copper: EPA Lead and Copper Rule sampling data
- Radon: EPA Map of Radon Zones
- Enforcement: EPA ECHO database
- Filter recommendations: NSF/ANSI certified products
Updated daily.
Frequently Asked Questions
Your Water is Safe — Here's How to Keep It That Way
Grade B is excellent news. Here's what proactive homeowners do to maintain water quality:
Annual Water Testing
EPA recommends annual testing even with clean water. Home test kits: $20-$50. Catches changes before they become problems.
Maintenance Filtration
A basic carbon filter removes chlorine taste and catches emerging contaminants like PFAS that aren't yet fully regulated.
Plumbing Check
Even safe city water picks up lead from home pipes. If your home was built before 1986, a one-time pipe inspection is recommended.