A cross-connection is any temporary or permanent connection between a public water system or consumer's potable (i.e. 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. Explore our FAQ below to learn more.
A cross connection is any temporary or permanent connection between a public water system or consumer's potable (i.e., 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.
Cross connections can occur at many points throughout a distribution system and a community's plumbing infrastructure. Cross connections can be identified by looking for physical interconnections (or arrangements) between a customer's plumbing and the water system. Some specific examples of backflow incidents that can occur are:
Backflow is the undesirable reversal of flow of non-potable water or other substances through a cross-connection and into the piping of a public water system or consumer's potable water system.
There are two types of backflow:
Backsiphonage is backflow caused by a negative pressure, such as a vacuum or partial vacuum, in a public water system or consumer's potable water system. The effect is like drinking water through a straw.
Backsiphonage can occur when there is a stoppage of water supply due to nearby firefighting, a break in a water main, etc.
Backpressure backflow is backflow caused by a downstream pressure that is greater than the upstream or supply pressure in a public water system or consumer's potable water system.
Backpressure can result from:
A backflow preventer is a means or mechanism to prevent backflow:
The responsibilities of an owner of a cross connection are defined in the Massachusetts Department of Environmental Protection’s Cross Connection Control Program Regulations - 310 CMR 22.22 (refer to mass.gov/doc/310-cmr-2222-cross-connection-regulations-0/download). Per 310 CMR 22.22 (4), the owner of any cross connection protected by a double check valve assembly or reduced pressure backflow preventer shall:
For Aquarion’s rules and regulations, including regarding Cross Connections, visit our Rules and Regulations page.
Safe, clean drinking water is essential to the health and well-being of each one of us as well as to society as a whole.
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