Backflow is a plumbing issue that can pose serious health risks by allowing contaminated water to flow backward into your home’s clean water supply. Understanding backflow, its causes, and how to prevent it is essential for protecting your household from potential water contamination. At Hansen Family Plumbing & Air, we are all about education. We want our customers to understand exactly what we are repairing, how it works within your home’s plumbing system, and why proper installation and repairs are crucial. Learn more about backflow and the various systems installed in your home to prevent this below!
What is Backflow?
Backflow occurs when the normal flow of water in a plumbing system is reversed, allowing non-potable (contaminated) water to enter the clean water supply. This can introduce harmful bacteria, chemicals, and other pollutants into the water you use for drinking, cooking, and bathing.
Potable Water vs. Non-Potable Water
- Potable Water:
Potable water is water that is safe for human consumption, meaning it has been treated and tested to ensure it is free from harmful contaminants, pathogens, and pollutants. This water meets rigorous health standards, making it suitable for drinking, cooking, and personal hygiene. Municipal water supplies, for example, undergo extensive treatment processes to maintain potability and ensure public health. - Non-Potable Water:
Non-potable water is water that has not been treated to meet safety standards for human consumption. It may contain contaminants, chemicals, or pathogens that make it unsafe to drink. While it isn’t suitable for drinking, non-potable water can often be used for other purposes such as irrigation, industrial processes, or flushing toilets—provided that proper precautions are taken to prevent accidental ingestion or contact with drinking water supplies.
What Causes Backflow?
Backflow happens when water in your home’s pipes starts flowing the wrong way, mixing dirty water with the clean water you rely on. In many households, this can occur because of changes in water pressure. For example, if there’s a sudden surge from a pump or an issue with your irrigation system, it can force water in the wrong direction. Another common issue is when a hose or pipe is connected in a way that allows water from a contaminated source—like a garden or outdoor faucet—to mix with your household supply. This is why it’s important to have proper backflow prevention devices and to check your plumbing connections regularly.
Why is Backflow Dangerous?
Backflow can introduce dangerous contaminants into your home’s water supply, including:
- Fertilizers and pesticides from irrigation systems
- Bacteria and sewage from cross-connections with wastewater pipes
- Chemical cleaners and soaps from industrial or household use
Consuming or coming into contact with contaminated water can lead to serious health issues such as gastrointestinal illnesses and infections.
How Do PVBs Work to Prevent Backflow?
Pressure Vacuum Breakers (PVBs) are a type of backflow prevention device commonly used in irrigation systems. Here’s how they work:
- Mechanism: A PVB allows water to flow in one direction through a check valve. When water flow stops, an air inlet valve opens, breaking any vacuum that might otherwise draw contaminated water back into the clean supply.
- Installation Considerations: For a PVB to function properly, it needs to be installed with adequate space and proper alignment with the water supply line. This ensures that the check valve and air inlet function as designed during both normal operation and pressure fluctuations.
The Impact of Shutoff Valves on PVB Performance
Shutoff valves play a critical role in your plumbing system by allowing you to control water flow. However, their placement and condition can significantly affect how well a PVB works:
- Proximity Issues: If a shutoff valve is installed too close to a PVB, it can create a pressure build-up. This may prevent the PVB’s air inlet from opening at the correct moment, reducing the device’s effectiveness at breaking the vacuum and preventing backflow.
- Pressure Dynamics: Proper water pressure is essential for a PVB’s optimal operation. A malfunctioning or improperly adjusted shutoff valve can alter the pressure dynamics, potentially impairing the PVB’s ability to detect and correct a reversal in flow.
- Maintenance: Both PVBs and shutoff valves should be maintained regularly. Over time, a worn shutoff valve can compromise the backflow prevention system by affecting water pressure and flow characteristics, making it harder for the PVB to function correctly.
How Homeowners Can Prevent Backflow
- Install a Backflow Preventer
- A backflow prevention device stops water from flowing in reverse, protecting your home’s drinking water.
- Some homes are required by code to have a backflow preventer, especially those with irrigation systems, fire sprinklers, or well water.
- Regularly Test and Maintain Backflow Devices
- Over time, backflow preventers can wear out or fail, so they should be tested annually by a licensed plumber.
- Many municipalities require annual testing to ensure compliance with water safety regulations.
- Be Mindful of Cross-Connections
- Avoid submerging garden hoses in pools, buckets, or sinks.
- Use hose bib vacuum breakers to prevent contamination from outdoor faucets.
Protect Your Home’s Water with Hansen Family Plumbing & Air
If you’re unsure whether your home has proper backflow prevention, or if you need testing and maintenance, Hansen Family Plumbing & Air is here to help! Our licensed plumbers provide expert backflow testing, installation, and repairs in Mesa, AZ, and the Greater Phoenix area. Contact us today to ensure your home’s water stays clean and safe!
