What is a Cross-Connection?

"Cross-connection" means any actual or potential connection or structural arrangement between a public water system, including a piping system connected to the public water system and located on the premises of a water user or available to the water user, and any source or distribution system containing liquid, gas, or other substances not from an approved water supply.

What is a Backflow?

"Backflow" is an undesired or unintended reversal of flow of water and/or other liquids, gases, or other substances into a public water system's distribution system or approved water supply. This can result from reduced pressure on the drinking water system, such as a water main break, pump failure, or emergency firefighting (backsiphonage) or when the pressure from a non-potable source exceeds the pressure in the water system (backpressure). 

How are Cross-Connections Prevented?

To prevent backflow issues, the City of Fullerton runs a cross-connection program that includes site surveys and annual backflow testing. Backflow prevention assemblies are installed usually right after the water meter for industrial, commercial, and sometimes residential properties-to protect the water system from contamination. The City currently has about 4,200 backflow devices in place.