Water Systems Directory
Look up any of 32,971 U.S. public water systems by ZIP code or city. EPA violation history, contaminant data, and a safety score for each.
Find your water system
Enter a ZIP code or city to see the public water system that serves it, its EPA compliance history, and safety score.
Largest water systems
New York City System
CNew York · 8,271,000 people
Los Angeles-city, Department of Water & Power
CCalifornia · 3,875,566 people
City of Houston
ATexas · 2,970,543 people
Chicago
CIllinois · 2,746,388 people
Mwra
AMassachusetts · 2,660,000 people
MDWASA - MAIN SYSTEM
CFlorida · 2,377,460 people
SAN ANTONIO WATER SYSTEM
ATexas · 2,113,151 people
WASHINGTON SUBURBAN SANITARY COMMISSION
CMaryland · 1,900,000 people
City of Phoenix
DArizona · 1,695,000 people
PHILADELPHIA WATER DEPARTMENT
APennsylvania · 1,600,000 people
CITY OF BALTIMORE
CMaryland · 1,600,000 people
Las Vegas Valley Water District
ANevada · 1,539,277 people
Most EPA violations on record
Moa Municipality of Anchorage
CAlaska · 292 violations
Mingo County Public Service District - Naugatuck
BWest Virginia · 233 violations
Albuquerque Water System
FNew Mexico · 220 violations
TUCSON CITY OF
DArizona · 218 violations
Metropolitan Dwid
DArizona · 218 violations
Usaf Davis Monthan Afb
DArizona · 218 violations
Lago Del Oro Water Company
CArizona · 218 violations
Belen Water System
CNew Mexico · 216 violations
City of Presidio
CTexas · 199 violations
Orange County Wcid 1
CTexas · 191 violations
Hominy
COklahoma · 186 violations
Craigsville Public Service District
CWest Virginia · 177 violations
Browse by state
Every public water system, grouped by the state it serves.
Data: U.S. Environmental Protection Agency (EPA) SDWIS
Get safety alerts
Free updates when EPA data changes for this area. No spam.
Unsubscribe anytime. Privacy Policy.