Water Quality in Washington, DC: 33 Violations - Grade N/A

Data: EPA Safe Drinking Water Information System (SDWIS)

Water Quality Overview

Washington, District of Columbia has directly mapped EPA water-system data for 34 ZIP codes. This page reports typed compliance facts and does not relabel the multi-source Home Safety Score as a drinking-water grade.

The available EPA records report 33 violations, including 3 health-based violations across 34 directly mapped ZIP records with reported counts.

Lead Levels

The average 90th percentile lead level across Washington water systems is 0.0020 mg/L - within EPA limits. No exceedances appear among the 34 ZIP records with known lead status.

With 73% of homes built before 1986, Washington 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.

Water Systems Serving Washington

Washington is served by 2 community water systems regulated under the Safe Drinking Water Act. These systems collectively serve approximately 671,768 people across 274 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 109 enforcement actions against water systems serving Washington. Enforcement actions range from informal compliance assistance to formal orders and penalties.

How to Check Your Water in Washington

1. Enter your ZIP code on ZipCheckup to see your specific water system data, including contaminant levels and violation history

2. Request your CCR - your water utility must provide an annual Consumer Confidence Report with detailed test results for all monitored contaminants

3. 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

4. Consider filtration - NSF-certified filters can remove specific contaminants. Reverse osmosis removes the broadest range; activated carbon is effective for chlorine and many organics

5. Check for advisories - monitor your local utility website and local news for boil water advisories or system alerts

Contaminants Detected in Washington Water Systems

The following contaminants have been detected or caused violations across Washington's water systems:

MCL = Maximum Contaminant Level (EPA enforceable standard). Health-based violations indicate levels that may pose direct health risks.

Violation Trend Over Time

Year-by-year EPA violations recorded for water systems serving Washington:

Violation counts have remained stable over the observed period.

EPA Enforcement History

The EPA and state regulators have taken 13 enforcement actions against water systems serving Washington. Recent actions:

Enforcement actions range from informal compliance assistance to formal orders and penalties. The most recent action was on 2026-03-24.

Washington vs. Nearby District of Columbia Cities

How Washington's water quality compares to similar cities in District of Columbia:

Recommended Water Filters for Washington

Based on contaminants detected in Washington's water supply, these filter types are recommended:

Granular Activated Carbon (GAC, whole-house or under-sink)

• Removes: Chlorine
• Effectiveness: 95-99%
• Cost range: $100–$600
• Certification: NSF/ANSI 42
• Recommended products:
  • Aquasana AQ-5200
  • Waterdrop Chubby Pitcher
  • Berkey Travel

Granular Activated Carbon (GAC, whole-house POE)

• Removes: Total Trihalomethanes (TTHMs), Perfluorooctanoic acid (PFOA)
• Effectiveness: 80-99%
• Cost range: $400–$2000
• Certification: NSF/ANSI 53
• Recommended products:
  • Aquasana AQ-5200
  • Aquasana EQ-1000 Rhino
  • Waterdrop G3P800

Granular Activated Carbon (GAC, under-sink or whole-house)

• Removes: Haloacetic Acids (HAA5)
• Effectiveness: 60-80%
• Cost range: $100–$600
• Certification: NSF/ANSI 53
• Recommended products:
  • Aquasana AQ-5200
  • Aquasana EQ-1000 Rhino

Water Quality by ZIP Code in Washington

EPA coverage and recorded violations can differ across Washington's ZIP codes. Missing counts are shown as unavailable, not zero:

Common Questions About Washington Water

These are the most common questions residents search for about water quality in Washington, District of Columbia:

Is Washington water hard or soft? Water hardness varies by source. Washington's 2 water systems use multiple sources. Check your ZIP code report for specific hardness data.

Can I drink Washington tap water? City-level EPA records cannot determine safety at a specific tap. The measured subset contains 3 health-based violations; check the affected utility record and consider certified testing.

What is the best water filter for Washington? Based on detected contaminants, a granular activated carbon (gac, whole-house or under-sink) filter is most recommended. See our Water Filter Matcher for personalized recommendations.

Washington vs. District of Columbia Average

Understanding how Washington compares to the broader District of Columbia 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 Washington.

ZIP Codes in Washington

Washington spans 274 ZIP codes. EPA water-system coverage is available for 34 directly mapped ZIP codes. 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

Source reporting periods vary. See each cited source for its publication schedule.