What does the term pollution mean in relation to water quality?

The term pollution in relation to water quality refers to a serious impairment of water quality by extraneous matter. Pollution occurs when harmful substances are introduced into the water, which can have significant adverse effects on ecosystems, human health, and overall water usability. This definition encompasses various contaminants, including chemicals, pathogens, heavy metals, and nutrients, which can degrade water quality to levels that are unsafe for consumption or harmful to aquatic life.

In this context, pollution is not simply a minor change in water quality; rather, it is focused on substantial negative alterations that can disrupt the natural balance of water bodies. It's also distinct from a complete blockage of water flow, which pertains to physical obstructions rather than quality degradation. Additionally, while a gradual increase in water temperature can affect aquatic life, it is not inherently defined as pollution unless it leads to detrimental ecological consequences. Therefore, understanding pollution as a serious impairment captures the critical aspects of water quality management and environmental protection.