What Is Backflow Testing And How Does It Work?

Backflow testing is a crucial procedure that ensures the water we use daily is safe and uncontaminated. But what does it involve, and why is it so important? 

At Diamondback Plumbing & Cooling, we’re committed to not only providing top-quality backflow services but also educating our customers on how their systems work to protect their health and homes. In this article, we’ll demystify backflow testing and take a closer look at its critical role in maintaining safe potable water systems. 

Whether you’re a homeowner, business owner, or simply curious about how it all works, you’re in the right place to learn about keeping your water supply secure.

What is Backflow Testing and Why Is It Important?

Backflow testing is a specialized process conducted to make sure that your drinking water remains uncontaminated by preventing the reverse flow of water from possible sources of contamination. 

Essentially, it’s a safety check for your water supply system that ensures dirty water does not flow back into your clean water lines, which can happen due to changes in pressure within the system. This procedure is crucial given that a breach of this safeguard can lead to serious health hazards from pollutants and bacteria entering the drinking water. 

Regular backflow testing, typically carried out by certified professionals, plays a pivotal role in maintaining public health and upholding sanitary standards for water systems in residential, commercial, and industrial properties. It’s a preventative measure and a regulatory requirement in many areas to protect the community’s well-being.

How Does Backflow Testing Work?

Backflow testing is a systematic procedure executed to verify the proper functioning of a backflow prevention device, which is designed to stop the reverse flow of water into a clean water supply. The testing process involves several steps and tools to ensure accurate results.

A certified backflow prevention assembly tester starts by shutting off the downstream water flow to isolate the backflow device. They then connect a specialized test kit, which typically includes gauge equipment that measures the pressure in various chambers of the backflow preventer. The tester will check for a drop in pressure that indicates the prevention device’s check valves are operating correctly and preventing backflow.

Test kits often consist of differential pressure gauges, hoses, and fittings that must accurately fit the test cocks of the backflow prevention assembly. A successful test will confirm that each valve within the device opens and closes properly, ensuring that contaminated water cannot siphon back into the clean water supply due to back pressure or back siphonage.

After performing the test, the tester records and submits the results to the local water provider or the designated regulatory body. If the device passes the test, it remains in service. 

Otherwise, it requires immediate maintenance or replacement to protect the potable water from potential contamination. Regular annual testing is mandated to maintain constant vigilance against backflow incidents.

Health Risks Associated with Backflow

Some of the health risks associated with backflow include the following:

Contamination of Drinking Water

The most immediate risk of a backflow incident is contaminating a community’s drinking water. When backflow preventers fail, pollutants such as pesticides, human waste, and chemicals from industrial processes can be introduced into the potable water supply. This can lead to waterborne diseases, which are dangerous for individuals with compromised immune systems.

Chemical Poisoning and Toxic Exposure

Chemicals used in industrial areas or household cleaning products, when drawn back into the water supply, can result in chemical poisoning. Symptoms can range from nausea and headaches to more severe health issues, including organ damage and neurological impairments.

Increase in Disease Transmission

Backflow can facilitate the transmission of diseases as it can carry bacteria and viruses into the drinking water supply. These pathogens can cause diseases like dysentery, salmonellosis, and hepatitis, known to spread through contaminated water. Regular testing helps to prevent these pathogens from compromising the health of a population.

Heavy Metal Accumulation

In certain cases, backflow can accumulate heavy metals like lead and mercury in the water supply due to the reverse flow from industrial sources. Prolonged exposure to heavy metals can lead to a condition known as bioaccumulation, which has chronic health impacts, including kidney damage and cognitive dysfunction.

Unpleasant Water Taste and Odor

While not as severe as other health risks, a compromised water supply can lead to an unpleasant taste and odor. This can indirectly affect hydration levels if individuals avoid drinking what they perceive to be foul-smelling or tasting water, leading to unwanted health implications like dehydration.

Regulatory Requirements for Backflow Testing in Arizona

In Arizona, especially in Phoenix, backflow prevention and testing are taken very seriously due to the potential health risks involved. 

The Arizona Department of Environmental Quality (ADEQ) mandates that all water suppliers develop and enforce a backflow prevention program to protect the public water supply from contamination. Under these programs, water customers who have the potential to impact the quality of the water due to backflow must install approved backflow prevention assemblies.

Regulations require that these assemblies be tested upon installation, annually after that, and whenever they are repaired or relocated. A certified backflow prevention assembly tester must perform the testing, and the test results must be submitted to the local water provider for review to ensure compliance with state and local standards. 

In Phoenix, the Water Services Department’s Backflow Prevention Program oversees these protocols and maintains a list of certified testers available to the public.

The guidelines are particularly stringent for commercial properties and specific residential scenarios with a higher risk of contamination, such as homes with residential fire sprinkler systems. It’s not only about adhering to these regulations for compliance but also about the active role that these measures play in safeguarding community health.

The City of Phoenix is very proactive, ensuring that backflow prevention devices are regularly tested and maintained. Failing to comply with these regulations can result in water service interruption and fees, emphasizing the importance of regular backflow testing as a civic responsibility.


Backflow testing is not just a legal requirement but an essential component of public health protection. Diamondback Plumbing & Cooling recognizes the critical nature of this service and is committed to assisting property owners in meeting their regulatory obligations and safeguarding their water against contamination. 

Trust our experts at Diamondback Plumbing & Cooling for reliable backflow testing and prevention services. Schedule your annual backflow test with us today and ensure your water remains safe and pure for everyone who depends on it. 

Give us a telephone call today to learn how we can help you maintain the integrity of your drinking water.

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