What Causes Backflow?

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You know how when you’re washing the dishes, the water is running, the leftover food and junk get washed off the plate, then all the soap, water, and stuff go down the drain, never to be seen again. Well, imagine that wastewater came back. Bad situation, right? That situation has a name, and it’s called backflow.

Backflow puts contaminated water into the clean water supply, putting those who use that clean water at risk. Here’s what causes backflow and what you can do to prevent it.

What is Backflow?

A simple definition of backflow is unwanted water that flows in the opposite direction. Water and waste should be going through your pipes to the outside of your home, not the other way around. Prevention is the best way to solve backflow issues, so homes and businesses should take steps to reduce the chances of a backflow incident.

What Causes Backflow?

Backflow can happen in two ways.

What Causes Back-Pressure Backflow?

Backpressure backflow occurs when the system’s pressure outweighs the supply—for example, heat expansion from a boiler or increased pressure in the non-potable source.

What Causes Back-Siphonage?

Back-siphonage is created when a vacuum (not the machine) creates a suction of negative pressure in the pipeline. You may be familiar with how siphoning works in general; a suction causes a liquid to be moved from one place to another. When back siphoning happens, it sends wastewater in the wrong direction.

How to Prevent Backflow

Backflow can be a significant disruption to your home and a health risk for you and your family. One of the most common solutions is a backflow prevention valve.

What Is a Backflow Preventer Valve?

  • When air gaps are not present in the pipeline, a valve can help prevent backpressure.
  • Air gaps are preferable for preventing larger-scale contamination.
  • These gaps protect against backpressure and back siphoning and should be installed by a professional plumber.

Expert Backflow Prevention & Knowledge

Backflow can be a dangerous and inconvenient problem, but the plumbing experts at Brownie's Septic and Plumbing, LLC can help you establish all the tools at your disposal. Call us today at for professional inspection and repair services.

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