Surveillance Reports for Drinking Water-associated Disease & Outbreaks

CDC publishes summaries of drinking water-associated waterborne disease outbreaks in the United States based on reports provided by state, local, and territorial health departments. These summaries help public health practitioners better understand the germs, settings, and contributing factors (for example, water was not disinfected properly) involved in outbreaks linked to drinking water. They also can help identify emerging waterborne disease threats and be used to inform and assess outbreak prevention measures.

Top 5 causes of drinking water outbreaks—United States, 1971–2020

Since 1971, CDC has published data on waterborne disease outbreaks associated with drinking water:

In 2021, CDC published an estimate of the burden and direct healthcare cost of infectious waterborne disease.

Links to historical surveillance reports and appendices are also available below.

Learn more about waterborne disease and outbreak surveillance milestones.

Most Recent Drinking Water-associated Outbreak Surveillance Data

CDC. Waterborne Disease and Outbreak Surveillance System (WBDOSS) Summary Report, United States, 2015. Atlanta, Georgia: U.S. Department of Health and Human Services, CDC, 2022.

2015 is the latest year a summary report is available due to limited capacity for waterborne disease surveillance and competing COVID-19 response priorities at CDC. Find more recent waterborne disease outbreak data on CDC’s National Outbreak Reporting System Dashboard.

Reports from 1971 through 2015









* Some of the documents on this page, due to their historical nature, are not able to be provided in an accessible (508-compliant) format. People with disabilities experiencing problems accessing these documents should contact CDC-INFO at, 800-232-4636 or the TTY number at (888) 232-6348 and ask for a 508 Accommodation PR#9342. If emailing please type “508 Accommodation PR#9342” without quotes in the subject line of the email.