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7 Signs You Need Backflow repair

Backflow, a common yet potentially hazardous plumbing issue, is characterised by water flowing in reverse from its intended direction, leading to possible contamination of your potable water supply. 

In this article, we outline seven key signs that you might require a backflow repair. Please remember, backflow can threaten the health of you and your family—diagnosing and fixing backflow issues are tasks best left to professionals like Fremantle Plumbing

What does ‘backflow’ mean? 

Backflow is a term used in plumbing to refer to an undesirable condition where water or other substances flow in the opposite direction from the intended direction within a piping system. This can lead to contamination of potable water supplies with non-potable or unsafe water.  

The primary cause of backflow is typically a change in pressure within the system, resulting from occurrences like water supply line breaks, water pressure drops, or sudden high demands on the water system. There are two main types of backflows: backpressure backflow and back-siphonage. 

  • Backpressure backflow: This happens when the pressure in a non-potable system, like in a recirculating system in a heating system or a pressurised fire sprinkler system, is higher than the pressure in the potable system that supplies it. This condition can force water from the non-potable system back into the potable system. 
  • Backsiphonage: This can occur when the pressure in a potable system drops due to events like a water main break or heavy water demand from firefighting operations. This drop in pressure can create a vacuum effect, drawing non-potable water up into the potable system. 

Backflow can be a serious issue because it can allow drinking water in plumbing systems to become contaminated and unusable. To prevent backflow, devices called backflow preventers are installed in plumbing systems. They are designed to automatically stop the backward flow of water, thereby preventing contamination. It is important to regularly inspect and maintain these devices to ensure they are working correctly. 

The 7 signs you need backflow repair 

Backflow is a serious plumbing issue that reverses water flow, potentially causing health and property risks. Here are seven signs suggesting that you might need backflow repair. 

#1 Water discolouration 

A change in water colour, such as brown, yellow, or cloudy water, can indicate a backflow problem. When the direction of water flow reverses, contaminated water may mix with your potable water, causing discolouration. This could also be due to rust in the pipes, soil intrusion, or pollutants. Although the water’s colour doesn’t directly affect its usability, it’s an essential visual cue that there might be a more profound problem.  

#2 Unpleasant odours 

A foul smell emanating from your tap water is another clear sign of potential backflow issues. The unpleasant odour, reminiscent of sewage or rotten food, indicates that your water supply has been compromised. Such contamination could come from a variety of sources, including wastewater systems, industrial processes, or even contaminated groundwater.  

#3 Changes in taste 

Alteration in the taste of your water should not be taken lightly. If your tap water starts to taste metallic, sour, bitter, or just generally odd, it might signal a backflow issue. The change in taste can occur due to various contaminants such as metals, chemicals, or bacteria getting into your water supply due to backflow.  

#4 Reduced water pressure 

Experiencing a sudden decrease in water pressure could be a sign of a backflow problem. This could occur if there’s a fault in your backflow preventer, the device designed to keep your water flowing in the right direction. Blockages, leaks, or mechanical failures in the preventer can cause water to flow backwards, reducing your system’s overall water pressure. 

#5 Frequent plumbing issues 

If you encounter recurring plumbing problems, such as drain clogs, leaks, or abnormal noises from your pipes, it may point to a more severe backflow issue. These problems could be symptomatic of pressure imbalances in your system or faults with your backflow prevention device, both of which can lead to backflow.  

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#6 Waterborne illness 

Recurrent bouts of illnesses such as gastrointestinal problems, skin irritations, or other waterborne diseases among household members could be a sign of water contamination caused by backflow. Pathogens, bacteria, chemicals, or other contaminants can enter your water supply due to backflow, causing health issues.  

#7 Pools of water 

If you find unexpected pools of water around your property, it could be a major backflow issue. These pools could form due to leaks caused by pressure changes, which might allow water to escape from your system. This sign is especially alarming as it could indicate a severe level of backflow, potentially contaminating your water supply. 

What does backflow repair entail? 

Backflow repair is a comprehensive procedure aimed at rectifying a serious plumbing issue where water reverses its normal flow direction within a plumbing system. This condition often results in contamination of a clean, potable water supply with dirty, non-potable, or potentially harmful water. Due to its serious implications on health and property, it’s crucial to promptly address and rectify any detected backflow issues. Here’s an in-depth look at the complex process of backflow repair: 

Detailed inspection and diagnosis 

The first and fundamental step in any backflow repair is a thorough and careful inspection of the plumbing system. This should be performed by a certified plumber or a backflow prevention specialist, such as a member of the team at Fremantle Plumbing, who are trained to recognise the signs of backflow and the underlying issues causing it. The inspection involves checking the plumbing layout, individual pipes, connections, and most importantly, the backflow prevention device. 

The backflow prevention device is a critical component of the plumbing system, designed to stop water from flowing in the wrong direction. If this device is malfunctioning due to damage, wear and tear, or a mechanical failure, backflow can occur. The specialist will scrutinise the device, checking for visible and hidden faults such as damaged seals, stuck check valves, or faults in the pressure relief valve. They may employ various techniques, including pressure tests and visual inspections, to diagnose the issue accurately. 

Precise repair or replacement 

Once the source of the problem has been diagnosed, the specialist will take appropriate measures to address it. If the issue is due to a faulty backflow prevention device, they will evaluate the extent of the damage to decide whether a repair or a complete replacement is required. 

Minor issues such as worn-out seals or a stuck valve might be fixed by repairing or replacing the particular components. However, in more severe cases where the device is extensively damaged or old, the specialist might recommend replacing the entire backflow prevention device. A new, high-quality device will provide better protection against potential backflow issues, ensuring the continued safety of your water supply. 

Comprehensive system flush 

Once the necessary repairs or replacements are completed, it’s important to flush the entire plumbing system. This is done to remove any contaminants that might have entered the water supply during the backflow incident. The specialist may employ several rounds of flushing, using clean, potable water to ensure all contaminants are effectively removed. This process is critical to restoring the safety and usability of your water supply post-repair. 

Rigorous testing 

Post-repair, it’s essential to validate the effectiveness of the repair work. The specialist will perform a rigorous backflow test to ensure the backflow prevention device and the entire plumbing system is functioning as intended. This involves creating a simulated backflow condition and verifying that the device successfully prevents the reversal of water flow. The test ensures that the repaired or replaced device is working optimally and safeguards your plumbing system against future backflow incidents. 

Routine maintenance and regular inspections 

After successfully dealing with a backflow issue, it’s paramount to maintain your plumbing system properly to prevent future occurrences. Regular inspection and maintenance of the backflow prevention device form a critical part of this process. You should schedule periodic inspections with a certified professional, ensuring they review the entire system, with a particular focus on the backflow prevention device. 

The professional will assess the device’s condition, checking for early signs of wear and tear, and ensuring it’s functioning correctly. They may also suggest preventive maintenance tasks, such as seal replacements or valve cleaning, based on the device’s make and model and the local water conditions. By adhering to a strict maintenance and inspection schedule, you can help prolong the lifespan of your backflow prevention device, securing your water supply against potential contamination. 


Backflow is a significant plumbing issue that, if left untreated, can lead to serious health hazards and property damage. Recognising the signs of backflow early on and getting them repaired promptly by residential plumbing Perth professionals like Fremantle Plumbing can mitigate these risks. Keep your water safe and your plumbing in excellent condition—contact us or book online today for a detailed inspection and expert repair services! 

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