US Tap Water Quality
by ZIP Code

Q: How do I find out what's in my tap water?

Enter your 5-digit ZIP code or city name above. We match it to the water utility serving that area and show the key contaminants it monitors, its EPA compliance status, and a safety assessment. For the legally binding detail, read your utility's annual Consumer Confidence Report (CCR), which every US water system must publish.

Q: Is tap water safe to drink in the United States?

For over 90% of Americans on community water systems, yes — the water meets all EPA Safe Drinking Water Act standards. Most violations occur in small rural systems, and most large-city concerns involve legacy plumbing (lead service lines) rather than the treated water itself.

Q: What does an EPA violation actually mean?

Violations range from serious (a contaminant exceeding a health-based Maximum Contaminant Level) to administrative (a missed monitoring deadline). Health-based violations trigger public notification requirements; utilities must tell you when your water is unsafe and what to do.

Q: Why does my ZIP code only show state-level results?

Our utility-level database covers the 100 largest US city systems so far. ZIP codes outside those service areas fall back to a state overview. ZIP matching is also approximate — ZIP boundaries don't follow utility service areas exactly — so always confirm with your water bill or CCR.

Look up the water utility serving your area, the contaminants it monitors, and whether it meets EPA standards — built on EPA Safe Drinking Water Act and EWG Tap Water Database reporting.

51

State guides

100

City water reports

940+

ZIP areas mapped

~49,000

US water systems

Water Quality by State

Every state guide covers major utilities, common contaminants, violation patterns, and the cities we've profiled in depth.

Alabama2 cities Alaska1 cities Arizona5 cities Arkansas0 cities California20 cities Colorado3 cities Connecticut0 cities Delaware0 cities Florida6 cities Georgia1 cities Hawaii1 cities Idaho1 cities Illinois1 cities Indiana1 cities Iowa1 cities Kansas1 cities Kentucky2 cities Louisiana2 cities Maine0 cities Maryland1 cities Massachusetts1 cities Michigan2 cities Minnesota2 cities Mississippi0 cities Missouri2 cities Montana0 cities Nebraska2 cities Nevada3 cities New Hampshire0 cities New Jersey2 cities New Mexico1 cities New York3 cities North Carolina6 cities North Dakota0 cities Ohio3 cities Oklahoma1 cities Oregon1 cities Pennsylvania2 cities Rhode Island0 cities South Carolina0 cities South Dakota0 cities Tennessee2 cities Texas10 cities Utah1 cities Vermont0 cities Virginia2 cities Washington3 cities Washington, DC0 cities West Virginia0 cities Wisconsin2 cities Wyoming0 cities

How This Lookup Works

Your ZIP code's first three digits identify a USPS regional area, which we map to the major water utility serving it — or to your state when no profiled utility covers that area. Utility profiles draw on EPA Safe Drinking Water Act compliance reporting, EWG Tap Water Database entries, and each utility's published Consumer Confidence Reports.

ZIP boundaries don't follow utility service areas exactly, so treat results as a starting point: your water bill names your actual provider, and their annual CCR is the authoritative record of what's in your water.

Frequently Asked Questions

How do I find out what's in my tap water?

Is tap water safe to drink in the United States?

What does an EPA violation actually mean?

Why does my ZIP code only show state-level results?

Sources & References

The safety rating and guidance on this page draw on the following sources. See our full methodology.

•US EPA Safe Drinking Water Act regulations
•EWG Tap Water Database
•The utility's most recent Consumer Confidence Report (CCR)
•WHO Guidelines for Drinking-water Quality

US Tap Water Qualityby ZIP Code

Water Quality by State

How This Lookup Works

Frequently Asked Questions

Sources & References

US Tap Water Quality
by ZIP Code