Straight from the Tap

What to Know about Backflow


We work hard to make sure the drinking water delivered to your home or business is safe at all times. One way we do this is by regulating backflow, which reduces the possible contamination of drinking water from other water sources.

A water system depends on pressure to keep water flowing in the proper direction through its distribution system and into customers’ homes. Backflow occurs when a sudden drop in pressure causes a reverse flow of water. This creates a safety issue if that backflow is from an unprotected cross-connection and the contaminated water is pulled back into the water system.

Common examples of cross connections include lawn irrigation systems, fire sprinkler systems, and garden hoses submerged in water.

Let's say you're washing your car and you turn your hose off but leave it submerged in a bucket of soapy water. If there is a sudden drop in water pressure, caused by something like a main break or a hydrant being opened, the flow of water can be reversed, sucking the soapy water from the submerged hose backward into your home plumbing.

An easy way to prevent this is by installing a backflow preventer (also called a vacuum breaker) on your spigot or replacing your spigot with one that has a backflow preventer built-in. Look for a device certified by the American Society of Sanitary Engineering (ASSE). Most are inexpensive and easy to install.

While we don’t require or regulate hose backflow preventers, backflow devices are required on certain water service connections and on all lawn irrigation systems to prevent contaminated water from reentering water mains and the public water supply. These types of devices must be installed correctly and regularly tested to ensure they work properly.

Learn more about backflow requirements for lawn irrigation systems and both private and commercial water systems on our website and in the Cleveland Water Backflow Prevention Policies.