What is backpressure?
A backpressure in the downstream piping that is higher than the supply pressure.
What is backsiphonage?
Negative or sub-atmospheric pressure in the supply piping.
What does a backflow device do?
A backflow device (BFD) prevents water from flowing backward from your plumbing into the public water system if the system loses pressure. You need a backflow prevention device if your water use may introduce the potential for contamination. To learn more about backflow prevention devices, click here.
Who needs a backflow device?
Anything that you attach to your plumbing that uses chemicals or can possibly introduce contaminants into our drinking water supply is a potential cross-connection. Some common examples include irrigation systems, fire protection systems, alternative water sources, and processes that involve the use of equipment, chemicals, or tools.
What type of backflow device am I required to install?
A Reduced Pressure Zone Backflow (RP) device must be installed on domestic water lines and chemical system fire lines.
Commercial customers must also install a Y-strainer in front of the device (before the water flows through the BFD). You may want to contact a licensed plumber for more information.
Do I need a plumbing permit?
If you are installing the device at a property within the City of Knoxville or in Knox County, you may need a permit and inspection. You can call 215-4311 in the City or 215-2325 in the County for more information.
If you are installing the device in Sevier or Jefferson county, please contact your County office to determine its requirements and call KUB for an inspection after installation.
Permits and inspections are only required on new installations. They are not required for maintenance or testing.
What should I know about installing a BFD?
A reduced pressure zone (RPZ) backflow device is required for protection of the water distribution system. The only exception is on non-chemical fire suppression stems where a double check (DC) backflow device may be used in place of an RPZ. To learn more about how to install a backflow prevention device, click here to reference KUB Standards and Specifications.
What should I know about maintaining my backflow device?
To learn more about your responsibilities associated with owning and maintaining a backflow prevention device please click here.
Can a backflow device be installed below ground level or in a pit?
Any backflow prevention device must be installed above ground and have accessibility for maintenance purposes. To learn more about the installation requirements for a backflow prevention device, click here to reference KUB Standards and Specifications.