What describes the process of sedimentation in water treatment?

Sedimentation in water treatment refers to the process where solid particles suspended in water settle out of the water column due to gravity. This process is an essential step in the treatment of water, particularly in the clarification phase before further purification.

During sedimentation, water containing sediment is held in a tank or basin, allowing the heavier particles—such as silt, clay, and debris—to gradually sink to the bottom. This not only helps to improve water clarity but also reduces the load on subsequent treatment processes, such as filtration and disinfection. Efficient sedimentation can significantly enhance the effectiveness of the entire water treatment system by ensuring that cleaner water flows to the next stages, ultimately contributing to safe drinking water.

The other options describe different processes in water treatment but do not pertain to the sedimentation process. For instance, filtration involves passing water through physical barriers to remove impurities, while chemical treatment with chlorine is aimed at disinfecting water. The use of ultraviolet light is another disinfection method that eliminates pathogens but does not involve sediment settling.