What is referred to as a "cross-connection" in a water supply system?

A "cross-connection" refers specifically to a physical connection between potable (drinking) water and non-potable (non-drinking) water. This definition is crucial in the context of water supply systems because such connections can create potential pathways for contaminants from non-potable sources to enter the potable water supply, posing serious public health risks.

Understanding this concept is vital for water distribution professionals, as they must implement measures to prevent cross-connections and ensure the safety of the drinking water supply. Cross-connections can occur in various scenarios, such as when irrigation systems are improperly connected to the drinking water supply or when a hose is submerged in a bucket of contaminated water.

In contrast, connections between two water treatment facilities, pipelines for stormwater drainage, or joints between two different water pipes do not inherently pose the same risk of contaminating the drinking water supply as cross-connections do. This distinction highlights the importance of safeguarding potable water from any potential sources of contamination.