What is the purpose of sedimentation in water treatment?

The purpose of sedimentation in water treatment is to remove suspended solids from water. During the sedimentation process, water is allowed to sit in a large tank known as a sedimentation basin or clarifier, where the denser particles settle to the bottom due to gravity. This settling action effectively reduces the concentration of suspended solids in the water, which is crucial for improving water clarity and quality.

This process is often a key step that precedes filtration and disinfection, as removing solids can enhance the effectiveness of those subsequent treatment methods. By reducing the solid load, sedimentation not only improves water quality but also helps protect equipment and prolong the lifespan of filtration systems.

The other options provided—killing bacteria, increasing water flow, and adjusting pH levels—do not directly relate to the role of sedimentation. These functions typically involve different water treatment processes such as disinfection for bacteria, pumps and engineering design for water flow, and chemical dosing for pH adjustment.