Backflow Hub

Your Resource for Everything Backflow

As water professionals, it's our duty to provide communities with safe, potable water by preventing the ever-present threat of backflow. Whether you're a beginner or a seasoned professional, stay up to date on the changing demands of our plumbing systems with resources developed by our backflow experts.

National Backflow Prevention Day
Thanks for making the second annual National Backflow Prevention Day a success! Join us next year on 8/16 to recognize backflow preventers and the professionals who install, test, and service them. 

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Backflow Basics

What is Backflow?

Backflow describes the undesirable reversal of the flow of water from its intended direction in any pipeline or plumbing system. Caused by cross-connections that can potentially allow contaminants into the drinking water system, backflow incidents occur when wastewater or other hazardous materials enter a potable water supply.

Two Types of Backflow

The two types of backflow are known as backpressure and backsiphonage. Backpressure is defined as pressure higher than the supply pressure, caused by a pump, elevated tank, boiler, or any other means that may cause backflow. Backsiphonage describes backflow caused by negative or reduced pressure in the supply piping, often caused by a sudden drop in supply pressure.

How Can Backflow Be Prevented?

Backflow prevention isn't just critical – it's mandated. All major plumbing code bodies address protection against backflow. Plumbing professionals ensure our communities are safe from the dangers of backflow by identifying cross-connections, specifying and installing the appropriate backflow preventers, and inspecting them to ensure they operate correctly and are up to code.

Backflow Preventers Frequently Asked Questions

Complete List of Backflow FAQs

Download backflow e-book series

Submit this form to receive links for these four e-books about backflow prevention strategies by email.

Backflow E-books

Examples of Backflow

Our Backflow Brands

Optimize safety, durability, and compliance with Watts’ complete line of backflow prevention devices. As a leader in valve technology for over 130 years, we offer a variety of high-quality backflow prevention solutions from the Watts family of brands

Featured Backflow Innovations


Field-proven protection against microbial-induced corrosion (MIC)
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Watts SentryPlus Alert™

The first system that offers automated flood protection
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Backflow Training

Catch up on best practices in backflow and water safety anytime, anywhere with eLearning courses and CEU webinars designed to fit your busy schedule.

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Backflow Resources

Check out Watts Backflow Videos

Learn more about Watts selection of backflow preventers.

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