Make an appointment

"*" indicates required fields

This field is for validation purposes and should be left unchanged.

The Ultimate Guide to Backflow Preventer Inspections

Power of the Plumbing Snake

Are you like most property owners who don’t give backflow preventers a second thought? You know they’re important, but unless there’s a problem, you don’t think about them at all. What if there was a way to make sure it was doing its job and that your home or business was always protected from potentially harmful water contamination?

This is the ultimate guide to backflow preventer inspections. In this guide, we’ll walk you through the basics of how backflow prevention works, explain why regular inspections are so important, and show you how to conduct your own inspection.

What Is Backflow and Cross Connection?

Backflow is the term used to describe when water or other liquids, gases, or substances flow backward into the clean water supply piping. This can happen for a variety of reasons.

A cross connection is a physical connection between two systems that would normally be separate, such as clean water and contaminated fluids. You’ll find these during routine¬†plumbing care.

What Are Backflow Preventers?

Backflow preventers are devices installed in your plumbing maintenance system to protect your water supply from contamination. They work by keeping the water in your pipes from flowing backward into the public water supply.

There are two main types of backflow preventers:


These devices use a check valve to keep water from flowing backward. They’re often used in commercial applications.


These devices rely on a float ball to block the flow of water backward. They’re used in residential applications.

Why Do I Need a Backflow Preventer?

If you’re connected to a public water supply, it’s required by law in many jurisdictions to have a backflow preventer installed.

Even if it’s not required by law, it’s still a good idea to have one installed to protect your water supply from contamination. In the Metro Detroit area, for example, the law requires that all commercial properties have a backflow preventer.

There are many potential sources of contamination, including:

  • Lawn irrigation systems
  • Swimming pools
  • Hot tubs and spas
  • Boilers and cooling towers

How Do I Know If My Backflow Preventer Needs Inspection?

In most cases, backflow preventers need an inspection once per year. However, there are some circumstances where more frequent inspections may be necessary, such as:

  • If there are changes to your plumbing system
  • If you’ve had any problems with your backflow preventer in the past
  • If you use a lot of water (e.g., for irrigation)

Why Are Backflow Preventer Inspections Important?

Backflow preventer inspections are important because they help to ensure that your device is functioning as it should. A well-functioning backflow preventer will help to keep your water supply clean and free of contamination.

Regular inspections also allow you to catch small problems before they become big ones. For example, if your backflow preventer is starting to rust, an inspection can help you identify the problem and take steps to fix it before it causes any major damage.

How Do I Conduct A Backflow Preventer Inspection?

There are three main parts of a backflow preventer inspection:

Visual inspection: This is a quick check to make sure that there’s no obvious damage to the device or its components.

Functional testing: This involves opening and closing the device to make sure that it’s working the right way.

Pressure testing: This test is done to measure the pressure inside the backflow preventer. It helps to identify any potential leaks.

What Happens if My Backflow Preventer Fails?

If your backflow preventer fails, it could allow contaminated water to flow back into your home or business. This is what is known as backflow: when water flows backward into your clean water supply.

Back Siphonage

Back siphonage is a type of backflow that can occur when there is a drop in water pressure. This can happen for a variety of reasons, including a broken water main or a power outage. When this happens, water can flow backward into your home or business through the pipes.

Back Pressure

Back pressure is another type of backflow that can occur when there is an increase in water pressure. This can happen for a variety of reasons, including a blocked sewer pipe.

What Are The Signs of Backflow?

The signs of backflow can vary depending on the type of contamination. However, some common symptoms include:

  • Foul-smelling water
  • Water that tastes bad
  • Unusual colors or textures in the water

If you notice any of these signs, it’s important to contact a professional backflow testing company right away. They’ll be able to conduct a test to determine if there is a problem with your backflow preventer.

How to Prevent Backflow

The best way to prevent backflow is to have a well-installed and maintained backflow-preventer device. It is important to have your backflow preventer device inspected regularly to make sure it is working as it should.

Most experts recommend having an inspection at least once per year. Some jurisdictions may require more frequent inspections, so be sure to check with your local authorities to see if there are any specific requirements in your area.

Backflow Preventer Inspection Requirements

Here’s what to expect from a backflow preventer inspection.

First, the device must be accessible for inspection, testing, and servicing. The inspector must be able to safely and easily get to the device for the inspection.

The inspector must be able to identify all parts of the device. This includes the inlet and outlet connections, the relief valve, and the strainer.

The inspector must be able to operate all parts of the device. This includes opening and closing the device, as well as opening and closing the relief valve.

The inspector must be able to measure the pressure inside the device. They must be able to identify any leaks in the device and any corrosion or damage to the device.

The inspector must be able to identify any potential problems with the way the device is installed.

Your device should be tested when:

  • First installed
  • Annually
  • When relocated, repaired, or replaced
  • When there are changes to the water system
  • If there is a change in the use of water on the property
  • If there are any signs that the device is not working as it should

Find Plumbers Near You

Backflow preventers are important pieces of equipment that help to keep your water supply clean and free of contamination. They should be inspected routinely to ensure that they are functioning as they should. 

In the Metro Detroit area, the experts at Water Works Plumbing are here to help with all of your backflow preventer inspection, testing, and plumbing maintenance needs. Contact us today to make an appointment.

"*" indicates required fields

Request an appointment

Fill out our online form and one of our friendly, professional plumbers will be at your doorstep anywhere in the Metro Detroit area as soon as possible.

MM slash DD slash YYYY

$22 Off

Any Service For New Customers

(Cannot be combined with other discounts)