Define the term "total dissolved solids" (TDS).

The term "total dissolved solids" (TDS) refers to the sum of all inorganic and organic substances present in a liquid. This includes various types of ions and molecules that can dissolve in water, such as salts, minerals, and organic matter. TDS is a crucial indicator of water quality, as high levels may affect the palatability, usability, and safety of the water for both humans and aquatic life.

Understanding TDS is essential for water operators because it impacts the physical and chemical properties of water, including its electrical conductivity, corrosion potential, and aesthetic qualities. Monitoring TDS helps ensure that water remains within acceptable standards for drinking water and other uses.