What is a cross-connection?
A cross-connection is any connection (whether temporary or permanent) between Columbus Water Work’s water distribution system and any source or system containing water or other substances that may not be suitable for drinking. An example of a cross-connection would be an irrigation system connected to a customer’s drinking water system.
A cross connection is a point in a plumbing system where the potable water supply is connected directly or can be connected directly to a non-potable, potentially lethal source. Wherever an unprotected cross connection exists, backflow may occur due to either “backsiphonage” or “backpressure”, and pathogenic microorganisms can be carried into the potable water supply. Backsiphonage is caused by a negative or reduced pressure in the supply line to a facility or plumbing fixture. The principle causes of backsiphonage are: • High velocities in pipe lines that create a “venturi” effect. • Water main line repair or break which is lower than a service point. • Lowered water main pressure due to high water withdrawal rates such as fire fighting or water main flushing. • Reduced water main supply pressure on suction side of a booster pump. Backpressure may cause backflow to occur whenever a potable water system is connected to another system operating at a higher pressure. The principal causes
