Cross Connection

What is Cross Connection Control?

The Charter Township of Lyon Sewer & Water Department is responsible for providing safe drinking water to Lyon Township residents and businesses connected to the municipal system.  State and Federal laws, the Plumbing Code, the Michigan Residential Code, and the Charter Township of Lyon Ordinances require Lyon Township to verify that cross connections on private plumbing systems do not pose a contamination risk to the public water system through the enforcement of Michigan Department of Environmental Quality (MDEQ) Law and Rules for Cross Connection Control.

A cross connection is any arrangement of piping on a plumbing system that could allow a backflow of contaminants into the public drinking water supply.  A backflow occurs when a reversal of the normal flow of water occurs.  This could happen due to a drop in water pressure from a water main break or other failure.  It also could occur when a plumbing fixture such as boiler or pump generates more pressure than the public water supply and pushes the water back to the public drinking water supply system.  Garden hoses and irrigation systems may contain pesticides and bacteria that could contaminate the water supply.

What is a Backflow Device?

Backflow devices are installed on water lines to prevent backflows from occurring.  There are many types of backflow devices and MDEQ requires testing of these devices at a minimum of every three years.  Testable devices include Pressure Vacuum Breakers (PVB), Reduced Pressure Principle Backflow Assemblies (RPZ), and Double Check Valve Assemblies (DCVA).

Testing and Inspections of Backflow Devices:

Lyon Township's Cross Connection Control Program was approved by the State of Michigan in 1991.  Since then, commercial properties and sub division irrigation accounts have had routine inspections of backflow devices and annual reports are submitted to the township on testable devices.

However, a new MDEQ mandate requires all testable backflow devices on residential homes be tested every 3 years.  A typical testable backflow device you will find on a residential property will be a Pressure Vacuum Breaker (PVB) installed on a lawn irrigation line.  This device will be on the outside of the home and designed to prevent pesticides or herbicides from entering the water system.   Lyon Township requires all testable backflow devices in residential properties be tested every 3 years.

Only Licensed Plumbing Contractors can test, repair, and install Backflow Assemblies pursuant to State of Michigan Law - Public Act 733 (State Plumbing Act) of 2002.  Further, effective January 1, 2019, the plumbing contractors must be ASSE 5110 certified through the State of Michigan.

A list of certified testers can be found here and is available from Oakland County or  If a new backflow device is being installed, or repair is needed, a plumbing permit must be obtained through the Building Department.

Letters are mailed out to all residential and commercial properties who are required to test and submit test report.

Any time a cross connection is made with the township water supply, a backflow preventer must be installed.   A plumbing permit must be pulled for this work.  Work must be completed by a backflow prevention certified plumber.  To learn more about the Cross Connection Control program, click here to view the Cross Connection Control Program Manual.

Water customers must have a backflow preventer installed on their irrigation system.  A plumbing permit must be pulled for this work.  Work must be completed by a backflow prevention certified plumber.  Plumber contractor will need to complete the Backflow Preventer Test Form  and return that form to Melanie Schlacht by either dropping it off or mailing it to the Lyon Township Municipal Center,  located at 58000 Grand River Ave, New Hudson, MI 48165.  Alternatively, you can fax the form to 248-437-2336 or email it to