In groundwater harvesting, what is the main purpose of a sedimentation tank?

The primary function of a sedimentation tank in groundwater harvesting is to filter out impurities from the water. This process involves allowing water to sit in the tank, enabling heavier particles, such as silt, sand, and organic matter, to settle at the bottom due to gravity. The result is a clearer and cleaner water supply ready for further treatment or direct use.

Sedimentation is crucial because removing these impurities not only enhances water quality but also protects subsequent treatment processes and distribution systems from potential damage or inefficiency caused by particulates and contaminants. This aspect of water treatment is essential in ensuring safe and potable water for consumption and other uses.

The alternative options suggest functions that are not aligned with the primary purpose of a sedimentation tank. For instance, storing water for long periods, increasing water pressure, or heating water do not represent the process of sedimentation and its role in purification.