What is Backflow?

Backflow is the undesirable reversal of the flow of water from its intended direction in any pipeline or plumbing system. Backflow is dangerous because it can allow drinking water in plumbing systems to become contaminated and unusable. This can happen when pressure is reduced in the distribution system due to an unforeseeable main line break fire fighting, or other distribution system situation. 

The City of Longview Cross-Connection Control and Backflow Prevention Program’s main goal is to provide clean and safe drinking water to all water customers. One of the ways we protect our water supply within the distribution system is to require all potentially hazardous connections to use, maintain and regularly test backflow prevention devices in their plumbing systems.

Backflow prevention devices are mechanical plumbing devices installed in a plumbing system to prevent water from flowing backward in the system. A properly installed, tested and maintained backflow preventer at the service entrance to a building or property can reliably prevent the backflow of water of an unknown quality from flowing back into the public water system.