Water unsuitable for drinking is categorized as such. It may contain contaminants, pathogens, or dissolved substances that pose a health risk if consumed. Examples include untreated wastewater, industrial effluent, and certain types of graywater. This water can be safe for other purposes, such as irrigation or cooling, depending on the specific contaminants present.
The distinction between drinkable and undrinkable water is crucial for public health and safety. Throughout history, access to safe drinking water has been a determining factor in the well-being of populations. Utilizing water unsuitable for consumption for alternative applications can conserve potable water resources and reduce the demand on drinking water supplies. This approach is increasingly important in regions facing water scarcity.