What does non-potable water refer to?

Non-potable water refers to water that is not safe for human consumption due to various reasons such as contamination, presence of pathogens, or unsuitable chemical composition. This type of water can still be used for other purposes, such as irrigation, industrial processes, or non-consumptive recreational activities. Understanding the term is important in irrigation practices and water resource management, as using non-potable water for irrigation can help conserve potable water resources while reducing the risk of contamination to human drinking supplies.

The other options may suggest specific uses or conditions for water but do not encapsulate the primary definition of non-potable water, which is centered on its unsuitability for human consumption.