Published April 5, 2026 · Updated monthly
Is My Tap Water Safe to Drink? How to Check
Most US tap water is safe to drink. Of the 190 water systems in our database serving 73,281,703 people, the majority meet EPA standards. However, 72 systems have active health-based violations. Here is how to check your specific water system.
Step 1: Find Your Water System
Every public water system in the US has a unique PWSID (Public Water System ID). You can find yours by searching your zip code or city on Is Water Safe. Your annual Consumer Confidence Report (CCR), which your utility is required to send you, also lists the PWSID.
Step 2: Check the Water Safety Score
Our Water Safety Score (0-100, A-F) evaluates each system on health-based violations, contaminant exceedances, monitoring compliance, and violation resolution. Here is what each grade means:
- A (85-100) — No active health violations. Meets all EPA standards.
- B (70-84) — Minor issues resolved promptly. Meets health standards.
- C (55-69) — Some violations on record. Water may have elevated contaminants.
- D (40-54) — Multiple violations. Consider using a filter.
- F (0-39) — Serious health violations. Filtration recommended.
Top-Rated Water Systems
- East Bay MUD, CA — Score: 100, Grade: A, serves 1,442,800 people
- Alameda County Water District, CA — Score: 100, Grade: A, serves 344,000 people
- CWS - Bakersfield, CA — Score: 100, Grade: A, serves 267,881 people
- Contra Costa Water District, CA — Score: 100, Grade: A, serves 198,000 people
- Dallas Water Utility, TX — Score: 100, Grade: A, serves 1,356,479 people
Systems With Safety Concerns
- City of Jackson, MS — Score: 0, Grade: F
- Newark Water Department, NJ — Score: 5, Grade: F
- Tuscaloosa Water & Sewer, AL — Score: 8, Grade: F
- Atlanta, GA — Score: 10, Grade: F
- Shreveport Water System, LA — Score: 10, Grade: F
What to Do If Your Water Has Violations
- Install a water filter — NSF-certified filters can remove most contaminants. Choose a filter rated for your specific contaminants (check our contaminant pages for filter recommendations).
- Check your CCR — Your water utility must publish an annual Consumer Confidence Report listing all detected contaminants and violations.
- Test your water — Home testing kits ($20-150) can verify what is in your water. State-certified labs provide more comprehensive analysis.
- Contact your utility — Ask about their violation remediation plans and timeline.
Frequently Asked Questions
Most US tap water is safe. Of 190 water systems tracked, the majority meet EPA standards. However, 72 systems have health-based violations. Check your specific system on Is Water Safe.
Search your zip code or city on Is Water Safe to see your water system's full contaminant list, violation history, and safety score. Your utility is also required to publish an annual Consumer Confidence Report with detected contaminants.
If your water system has a C grade or below, a filter is recommended. For specific contaminants, choose an NSF-certified filter rated for that contaminant. Activated carbon filters handle most organic compounds, while reverse osmosis filters remove heavy metals and PFAS.