Backflow Prevention Device Testing

Experience has shown that there is not a mechanical device that can be depended upon unless it is checked, tested and maintained on a regular basis.  Backflow Prevention devices are required to be installed in specific locations to protect the safety of the drinking water.  These devices must be tested on a regular basis.

Are there any regulations regarding backflow prevention device testing?

Yes, the State of Michigan Department of Public Health, Administrative Rules for Michigan's Safe Drinking Water Act, Act 399, P.A. 1976 Michigan Plumbing Code 2000, and local Cross Connection Control (CCC) plan requirements.

How often do I have my backflow prevention devices tested?

All testable devices must be tested initially upon installation and should be tested at yearly intervals thereafter.  The Township inspector may require more frequent testing based upon degree of hazard, corrosive atmosphere or concerns with water quality.

How much will it cost to have my backflow prevention device tested?

The cost for testing will vary depending on the size of device, the location of the device, if the device is to be tested during normal working hours and which testing firm will be doing the testing.

For a list of certified backflow testers registered with Independence Township please contact the Department of Public Works at 248-625-8222 or click on the flowing link

If you would like to be on the list of Independence Township’s certified testers, please fill out the attached form and bring to the Independence Township Dept. of Public Works along with your valid Michigan driver’s license and your Michigan Certificate of Award Cross Connection Control card. 

Who can test or install backflow prevention devices?

A certified backflow prevention device tester.  This is a professional who has successfully completed and who has proven their ability in testing and satisfies the requirements of the Michigan Mechanical and Plumbing Contractors Association testers course.

Where can I obtain a list of certified testers?

Contact the Department of Public Works at 248-625-8222 for a listing of certified testers.

Are all backflow prevention devices testable?

No, the testable backflow prevention devices are:

  • Double Check Valve Assembly
  • Double Detector Check Valve Assembly
  • Pressure Vacuum Breaker
  • Reduced Pressure Backflow Preventor Assembly
  • Reduced Pressure Detector Assembly
  • Spill Resistant Vacuum Breaker

Will my water service be interrupted during the test?

Yes, the water supply to the backflow preventor must be turned off during testing.  Depending upon the type of device the time for testing typically takes 10 - 30 minutes.  Additional time may be needed for repairs, if required.

Are permits required?

Check with the building department regarding regulations for permit requirements.

The device tester will complete a form with the necessary information required by the water utility.  This form should be copied and retained for your records.  The original should be submitted to the Department of Public Works.

What is a backflow prevention device?

Any device that has been approved to prevent backflow into the public drinking water supply.  An approved backflow prevention device will prevent backflow-backsiphonage and backpressure.  The appropriate device will be determined during your inspection by the CCC inspector.

How long do I have to get my backflow prevention device tested?

The time allowed for completion of necessary corrections is determined by your local water authority.  Typically, they will mandate a timeframe.

It's true!  You can pollute your own drinking water without even realizing it.  Elimination of cross connections will help protect the water we drink.  The Safe Drinking Water Act of 1974 established national standards for drinking water.  The State and Local Governments are responsible for the enforcement of these standards, and the supervision of the public water supply.  It is the responsibility of Local Government to deliver safe drinking water to your tap.

What is a Cross Connection?

A cross connection is a direct or potential arrangement of drinking water piping that is or can be connected to a questionable source.  An example is the common garden hose submerged in a swimming pool.  Other examples are supply lines connected to boilers, process equipment, or bottom-fed tanks.

What is back-siphonage?

Back-siphonage is the reversal of normal flow in a system caused by negative pressure (vacuum or partial vacuum) in the supply piping.

What factors can cause back-siphonage?

Back-siphonage can be created when there is stoppage of the water supply due to repairs or breaks in the city main or increased demand at a location such as fire fighting.

What is backpressure backflow?

Backpressure backflow is the reversal of normal flow in the system due to downstream pressure being greater than the supply pressure.

What is the purpose of a cross connection control program?

Under State law, each municipality is responsible to ensure that commercial and industrial facilities within its jurisdiction are in compliance of State requirements preventing the use of faulty cross connections or backflow devices contained within the water system.  As a result of these mandates, the Charter Township of Independence will inspect all commercial and industrial facilities within the city.

Questions related to a cross connection program?

Please contact the Department of Public Works at 248-625-8222.