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

Not one violation appears in CA's EPA file for Fullerton — 2 monitored systems, all clear.

Water Quality Map: Fullerton, CA

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 Fullerton

Water quality varies across Fullerton's 8 ZIP codes. Check your specific ZIP for detailed contaminant data.

ZIP Code	Grade	Score	Violations	Health
92831	A	90	0	0	View report →
92835	A	90	0	0	View report →
92832	A	95	0	0	View report →
92833	A	95	0	0	View report →
92836	A	95	0	0	View report →
92834	A	99	0	0	View report →
92837	A	99	0	0	View report →
92838	A	99	0	0	View report →

Water Quality Overview

Fullerton, California receives a water quality grade of A with an overall score of 95 out of 100, based on EPA compliance data from the Safe Drinking Water Information System (SDWIS).

No EPA violations have been recorded for the 2 water systems serving Fullerton. This is a positive indicator, though it does not guarantee the absence of all contaminants — some substances (like PFAS) are not yet fully regulated.

What Grade A Means

A grade of A indicates excellent compliance with EPA drinking water standards. Fullerton's water systems have maintained strong performance in both contaminant monitoring and regulatory compliance.

Lead Levels

The average 90th percentile lead level across Fullerton water systems is 0.0015 mg/L — within EPA limits. No ZIP codes exceed the EPA lead action level.

With 79% of homes built before 1986, Fullerton 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 Fullerton

Fullerton is served by 2 community water systems regulated under the Safe Drinking Water Act. These systems collectively serve approximately 139,580 people across 8 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

How to Check Your Water in Fullerton

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

Fullerton vs. Nearby California Cities

How Fullerton's water quality compares to similar cities in California:

Recommended Water Filters for Fullerton

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

Reverse Osmosis (under-sink)

• Removes: Nitrate
• Effectiveness: 85-95%
• Cost range: $150–$500
• Certification: NSF/ANSI 58
• Recommended products:
  • Waterdrop G3P800
  • iSpring RCC7AK
  • APEC ROES-50

Water Quality by ZIP Code in Fullerton

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

Common Questions About Fullerton Water

These are the most common questions residents search for about water quality in Fullerton, California:

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

Can I drink Fullerton tap water? Fullerton's water receives a grade of A (95/100). No health-based violations have been recorded, but home testing is always recommended.

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

Fullerton vs. California Average

Understanding how Fullerton compares to the broader California 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 Fullerton.

ZIP Codes in Fullerton

Fullerton spans 8 ZIP codes. 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.

Your Water is Safe — Here's How to Keep It That Way

Grade A 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.