TapSafetyReport

Water Quality by ZIP Code: How to Check Your Tap Water

·By TapSafetyReport Team·TapSafetyReport

Why ZIP Code Matters for Water Quality

Your water quality depends on which water utility serves your address. In the US, there are over 50,000 community water systems, and the one serving your home determines what's in your tap water.

Many ZIP codes are served by a single water utility, but some areas — especially suburbs and unincorporated areas — may be served by multiple utilities. That means your neighbor across the street could have different water quality than you.

How to Check Your Water Quality

Step 1: Find Your Water System

The easiest way is to search for your city on TapSafetyReport. We map water systems to the cities they serve using EPA geographic data. You'll see which utility provides your water and its full quality report.

Step 2: Understand the Report

Your water quality report includes:

  • Water Quality Score (0-100): An overall grade based on contaminant levels and violations
  • Contaminant Table: Every tested contaminant, the detected level, and how it compares to EPA limits
  • Violation History: Any EPA violations the system has received
  • Water Source: Whether your water comes from groundwater or surface water

Step 3: Know the Key Numbers

Two numbers matter most for each contaminant:

  • MCL (Maximum Contaminant Level): The legal limit. Exceeding this is a violation.
  • MCLG (Maximum Contaminant Level Goal): The health goal, set with a margin of safety. Often lower than the MCL.
A contaminant can be present but still safe if it's below the MCL. However, some health advocates argue that the MCLG is the better benchmark for safety.

What If Your Water Quality Is Poor?

If your water system scores a C, D, or F, consider these steps:

  • Get a filter: NSF-certified water filters can remove specific contaminants. Match the filter to the contaminants found in your water.
  • Request your CCR: Your utility must provide an annual Consumer Confidence Report with detailed water quality data.
  • Test your water: Home test kits or EPA-certified lab tests can check for contaminants at your specific tap, including lead from your plumbing.
  • Report concerns: Contact your water utility or state drinking water program if you notice changes in taste, color, or odor.

Data Sources

All water quality data on TapSafetyReport comes from the EPA's Safe Drinking Water Information System (SDWIS), which tracks every community water system in the United States. This data is updated quarterly.

Search for your city to see your water quality report with the latest EPA data.