Regulatory Programs

A cross-connection is any temporary or permanent connection between a public water system or consumer’s potable (drinking) water system and any source or system containing non-potable water or other substances. An example is the piping between a public water system or consumer’s potable water system and an auxiliary water system, cooling system, or irrigation system.

Backflow Preventers 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 community water system.

Backflow can be caused by a sudden drop in the water pressure in a public water main, which can create a sub-atmospheric condition. For example, if a drop in pressure occurs while a hose is in a bucket of dirty water, that water could be sucked back into the public water system, potentially contaminating the water for other users. A drop in pressure could be caused by a variety of things, including a water main break, loss of power at a pump station, etc. Backflow preventers keep this from happening.

It is the customer’s responsibility to purchase and install the backflow preventer. The backflow preventer is installed to protect the public water supply against possible hazards in the customer’s plumbing system. The actual or potential cross connection belongs to the property owner and not to regulatory officials or the water utility. Once the water goes beyond the meter, water quality could be altered. The water utility does not want the water back, nor do the water customers want to purchase used water. If a backflow preventer is required to keep the water safe, then the person who created the cross connection (actual or potential) should purchase, install and maintain the backflow preventer.