What is a cross-connection?

A cross-connection is defined as a physical link between potable (drinking) water and non-potable water sources. This definition is critical in water distribution systems because it presents a potential risk for contamination of the clean water supply. If a backflow occurs, non-potable water could flow back into the potable system, leading to serious health hazards. Understanding the concept of cross-connections is essential for water distribution system operators and regulatory compliance, ensuring that measures such as backflow preventers are in place to protect public health and safety.

The other options, while related to water systems, do not accurately define what a cross-connection is. A connection between two water mains or a method of testing water quality does not entail the specific risk of contamination that a cross-connection presents. A type of water treatment process does not refer to connections between different water sources but rather to methods used in purifying water for consumption. Thus, the importance of recognizing a cross-connection lies in its role in safeguarding the integrity of potable water supplies.