What is a cross-connection in an irrigation context?

In the context of irrigation, a cross-connection refers to a physical link between potable (safe) water and non-potable (dirty) water. This connection poses a significant risk because it can allow contaminants from the non-potable water supply to enter the clean water supply during backflow conditions, which can happen due to changes in water pressure. Understanding cross-connections is critical for maintaining water quality and protecting public health, which is why many irrigation systems implement backflow prevention devices to mitigate such risks.

The other options do not accurately describe a cross-connection. A connection between two valves does not inherently involve the transfer of contaminants, while a type of water filter pertains to purification rather than the mixing of water supplies. A connector for irrigation pipes simply serves as a mechanical fitting, with no implications related to water quality or safety.