Know what’s in your tap.
TapGraded turns public EPA drinking-water data into a plain-English Tap Grade for every US water utility, city, and zip code.
How Tap Grades work
1
We pull EPA SDWIS, ECHO, and UCMR5 data for every public water system.
2
Health-based violations, lead sampling, and PFAS occurrence roll up into a single A-F score.
3
Look up your utility, city, or zip code and see exactly what’s being measured.
Featured contaminants
See what each contaminant is, its health-based limit, and which utilities have detected it.
Big cities, graded
A snapshot of the largest water utility in eight of the biggest states.
CITY OF HOUSTON
HOUSTON, TX · 2,970,543 served
NEW YORK CITY SYSTEM
VALHALLA, NY · 8,271,000 served
LOS ANGELES-CITY, DEPT. OF WATER & POWER
LOS ANGELES, CA · 3,875,566 served
CHICAGO
CHICAGO, IL · 2,721,308 served
MDWASA - MAIN SYSTEM
MIAMI, FL · 2,377,460 served
PHILADELPHIA WATER DEPARTMENT
PHILADELPHIA, PA · 1,600,000 served
MESA CITY OF
MESA, AZ · 466,000 served
SEATTLE PUBLIC UTILITIES
Seattle, WA · 1,161,961 served