Help protect our drinking water from contamination through cross-connections by installing an appropriate backflow prevention device at your home or business.
What is a Cross-Connection?
A cross-connection occurs when any physical arrangement whereby the public water supply is connected with any other water supply system, which contains, or may contain, contaminated water, sewage, or other waste or liquid of unknown or unsafe quality which may be capable of contaminating the public water supply as a result of backflow. Other connections can include a sewer, drain, conduit, pool, storage reservoir, or plumbing fixture, etc. Contamination occurs only if the contaminated water backflows or siphons into the water system, such as, chemicals from a business (e.g. a car wash, chemical plant, restaurant, dry cleaner) or from a lawn irrigation system. Cross-connections, which can occur at any pipe, valve, or fixture in the drinking water system, can be eliminated by utilizing a backflow prevention device.
What is the State Regulation for Cross-Connections?
Tennessee Department of Environment and Conservation (TDEC) Rule 0400-45-01-.17 states:
Pursuant to T.C.A. § 68-221-711(6), the installation, allowing the installation, or maintenance of any cross-connection, auxiliary intake, or bypass is prohibited unless the source and quality of water from the auxiliary supply, the method of connection, and the use and operation of such cross-connection, auxiliary intake, or bypass has been approved by the Department. The arrangement of sewer, soil, or other drain lines or conduits carrying sewage or other wastes in such a manner that the sewage or waste may find its way into any part of the public water system is prohibited. All community water systems must adopt an ordinance or policy prohibiting all of the above and submit a copy of the executed ordinance or policy to the Department for approval. All community water systems shall develop a written plan for a cross–connection control program to detect and eliminate or protect the system from cross–connections. The written plan must be approved by the Department.
After adoption and approval of the cross-connection ordinance or policy and plan, each community water system must establish an ongoing program to detect and eliminate or protect the system from hazards associated with cross-connections. Records of the cross-connection control program must be maintained by the supplier of water and shall include such items as date of inspection, person contacted, recommendations, follow-up, and testing results.
Community water systems shall ensure that cross-connections between the distribution system and a consumer’s plumbing are surveyed and/or inspected and determined not to exist or contain a significant risk or are eliminated or controlled by the installation of an approved backflow preventer commensurate with the degree of hazard.
What is a Backflow Prevention Assembly?
According to the Tennessee Backflow Prevention Association, a backflow prevention assembly, also known as a backflow preventer, is a mechanical device installed in a plumbing system to prevent water from flowing backwards in the system. State and local regulations require a properly installed, tested, and maintained backflow preventer where water pipes enter a building or property to prevent altered water from flowing back into the public water system if there is a pressure drop or a backpressure situation. The correct device must be used based on the potential hazard. High hazard (drinking water) installations, like domestic devices and lawn irrigation systems, must use a reduced pressure principle assembly or an air gap. Moderate to low hazard installations (non-drinking water), like fire sprinkler systems, typically use a double check valve assembly.
Who is Responsible for the Backflow Prevention Assembly?
Any water customer who has the potential for a cross-connection is responsible for purchasing, installing, and maintaining a backflow preventer. If you are unsure if a backflow preventer is needed, please complete and submit this survey. LUB is responsible for the quality of the water delivered to customers, including the execution of a cross-connection control program to monitor the presence, use, and testing of backflow preventers. Annual testing is directed by LUB through TDEC certified testers.
Approved Backflow Prevention Assemblies
Only devices currently approved by the Tennessee Division of Water Supply are to be used for the protection of Public Water Systems against backflow hazards. TDEC maintains a list of approved devices on their website or customers can contact LUB.
Approved Backflow Prevention Assembly Repair & Retest Companies
Backflow Prevention Assemblies must be repaired and retested within 30 days of a failed test. The cost of repairs and retests are the responsibility of the customer.
*Contact LUB for an up-to-date list of approved repair and retest companies.*
Cross-Connection Control Software
Customers with backflow preventers can login to the software for more information.
Cross-Connection Control Ordinance
Fire Line Protection Regulations
Backflow Prevention Device Installation Requirements
Cross-Connection Control Survey