What is water that does not meet the standards of potable water referred to as?

Water that does not meet the standards of potable water is referred to as non-potable water. This term specifically denotes water that is not safe for human consumption due to a variety of reasons, including the presence of harmful contaminants, lack of adequate disinfection, or overall poor quality that fails to meet regulatory standards for drinking water. Non-potable water may still be used for other purposes such as irrigation or toilet flushing, but it is crucial to recognize its limitations and potential health risks when it comes to consumption.

The other terms, while related, do not specifically capture the definition of water that is unsuitable for drinking. Unsafe water, for instance, can be an umbrella term that encompasses non-potable water but does not specifically identify it. Contaminated water implies the water has harmful substances, which could also suggest non-potability, yet the term itself lacks the directness of stating that it is unfit for consumption. Waste water generally refers to water that has been used and is discharged after domestic, industrial, or agricultural use, which differs from the definition of non-potable water as it can sometimes be treated for reuse or disposal.