Data: EPA Safe Drinking Water Information System (SDWIS) Last verified: 2026-05-03

On record with EPA: Allentown, PA has 117 water violations.

Water Quality Map: Allentown, PA

Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.

A B C D F

Water Quality by ZIP Code in Allentown

Water quality varies across Allentown's 9 ZIP codes. Check your specific ZIP for detailed contaminant data.

ZIP Code	Grade	Score	Violations	Health
18103	D	44	13	0	View report →
18104	D	44	13	0	View report →
18109	D	44	13	0	View report →
18175	D	48	13	0	View report →
18195	D	48	13	0	View report →
18102	D	49	13	0	View report →
18105	D	49	13	0	View report →
18101	D	54	13	0	View report →
18106	D	54	13	0	View report →

Water Quality Overview

Allentown, Pennsylvania receives a water quality grade of D with an overall score of 48 out of 100, based on EPA compliance data from the Safe Drinking Water Information System (SDWIS).

The 5 water systems serving Allentown have accumulated 117 EPA violations (all monitoring/reporting type). These violations are tracked across 9 ZIP codes serving approximately 191,625 people.

What Grade D Means

A grade of D indicates significant compliance issues. Allentown's water systems have accumulated violations that suggest ongoing water quality challenges. Residents should check their specific ZIP code report and consider water testing or filtration.

Lead Levels

The average 90th percentile lead level across Allentown water systems is 0.0070 mg/L — within EPA limits. No ZIP codes exceed the EPA lead action level.

With 77% of homes built before 1986, Allentown 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

Allentown is in EPA Radon Zone 1 (High risk). The EPA recommends all homes in Zone 1 areas be tested for radon. Radon is the second leading cause of lung cancer after smoking.

Water Systems Serving Allentown

Allentown is served by 5 community water systems regulated under the Safe Drinking Water Act. These systems collectively serve approximately 191,625 people across 9 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 90 enforcement actions against water systems serving Allentown. Enforcement actions range from informal compliance assistance to formal orders and penalties.

How to Check Your Water in Allentown

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

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 Allentown Water Systems

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

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 9 enforcement actions against water systems serving Allentown. Recent actions:

Enforcement actions range from informal compliance assistance to formal orders and penalties. The most recent action was on 2025-10-28.

Allentown vs. Nearby Pennsylvania Cities

How Allentown's water quality compares to similar cities in Pennsylvania:

Recommended Water Filters for Allentown

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

Reverse Osmosis (under-sink)

• Removes: Lead
• Effectiveness: 95-99%
• Cost range: $150–$500
• Certification: NSF/ANSI 58
• Recommended products:
  • Waterdrop G3P800
  • Aquasana AQ-5200
  • Clearly Filtered Pitcher

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, under-sink or whole-house)

• Removes: Haloacetic Acid 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 Allentown

Water quality varies across Allentown's ZIP codes. The table below shows the worst-scoring and best-scoring areas:

Common Questions About Allentown Water

These are the most common questions residents search for about water quality in Allentown, Pennsylvania:

Is Allentown water hard or soft? Water hardness varies by source. Allentown's 5 water systems use multiple sources. Check your ZIP code report for specific hardness data.

Can I drink Allentown tap water? Allentown's water receives a grade of D (48/100). No health-based violations have been recorded, but home testing is always recommended.

What is the best water filter for Allentown? Based on detected contaminants, a reverse osmosis (under-sink) filter is most recommended. See our Water Filter Matcher for personalized recommendations.

Allentown vs. Pennsylvania Average

Understanding how Allentown compares to the broader Pennsylvania 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 Allentown.

ZIP Codes in Allentown

Allentown spans 9 ZIP codes. The ZIP with the lowest water quality score is 18101. 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.