Back Pressure

What Is Backflow Backpressure?


Backpressure backflow is a plumbing system malfunction. A backflow prevents the flow of water from a higher level to a lower level. The City of Jackson, Michigan, states: “It can occur in any cross-connected plumbing system which builds higher pressure than that of the city’s water mains.” (1)

In plumbing, this is used to prevent contaminated water from going into the potable supply. Too much pressure in an area can cause backflow and lead to contamination of the water supply.

What Causes Backflow Backpressure?

Backflow is caused by two distinct mechanisms: back-siphonage and backpressure.


Backflow in a public water system or a private potable water system is caused by negative pressure (in other words, a vacuum or partial vacuum). It is similar to drinking water using a straw. Back-siphonage can occur when the water supply is interrupted due to nearby firefighting, a water main failure, or other factors.

Backsiphonage can be prevented by installing an air gap device at the highest point of the potable water system. Air gaps maintain pressure within the plumbing system, thus preventing backflow. Another way to prevent back-siphonage is by applying the following on the plumbing system:

  • Atmospheric vacuum breaker
  • Pressure type vacuum breaker
  • Barometric pressure loop


Backpressure is the most common cause. This happens when there’s excessive water pressure in an area.

Backpressure is generally caused by boilers, sprinkler systems, or power washing gear. This malfunction can be prevented by installing backwater valves. These are devices that are mounted on a pipe that allows water to only flow in one direction.

Why Be Concerned With Cross-Connection Control Devices?

A cross-connection is a piping structure that enables the connection of a potable water system to a source of possible pollution or contamination. It is critical to secure cross-connections to avoid backflow into drinking water. Backflow can eventually contaminate the entire public water supply, posing a danger to anyone who uses water for drinking, cooking, bathing, or any other purpose.

If an incident occurs that results in the contamination of public drinking water (as a result of faulty or unprotected plumbing connections), the property owner or occupant may be held liable for damages.

Backflow can eventually contaminate the entire public water supply, posing a danger to anyone who uses water for drinking, cooking, bathing, or any other purpose.

Cross Connection Control and Prevention Program

A Cross-Connection Control and Prevention Program (CCCP) was created in accordance with federal and state regulations to ensure or protect the public drinking water supply from contamination through sources existing downstream.

A hazardous situation may develop if onsite plumbing systems at our home create cross-connections that could affect the safety measures for a nearby source, which is why it’s vital to know about these program regulations beforehand. 

Contact Us at Southside Atlanta Backflow Repair

Backpressure backflow can be a massive problem for any property owner. If left untreated, contaminated water can flow into your home’s plumbing system and eventually contaminates the entire public drinking water supply.

To avoid this detrimental outcome, it’s always best to have an expert take a look at your plumbing system and/or conduct backflow testing for any potential problems that could arise in the future. If you need the experts for the job, contact us today at Southside Atlanta Backflow Repair. 

City of Jackson Michigan: