What is referred to when the quality of potable water is impaired?

The term used when the quality of potable water is impaired is "contamination." This specifically refers to the presence of harmful substances or pathogens in water that can compromise its safety for human consumption. Contamination can occur through various means, such as the introduction of heavy metals, chemicals, or microorganisms, making the water unsafe to drink and posing health risks.

Contamination differs from pollution, which typically refers to a more broad-based degradation of the environment, often involving pollutants being introduced into air, water, or soil. While all contamination could be considered a form of pollution, not all pollution necessarily involves the impairment of drinking water quality.

Supply failure pertains to situations where there is insufficient water supply available for consumption, while excess pressure refers to a condition in plumbing systems that can cause damage but does not directly address water quality. Therefore, contamination is the most accurate term in relation to the impairment of potable water quality.