The primary function of a sedimentation basin is to produce settled water with the lowest possible turbidity. Effective sedimentation is closely linked with proper coagulation and flocculation.
Proper sedimentation is necessary for an effective filtration process.
Sedimentation removes settled solids in order to decrease loading on filtration and other treatment processes. Basins designed for efficient sedimentation allow the water to move very slowly through the basin, where velocity and turbulence are low, allowing the solids to settle to the bottom of the basin. A baffle wall at the inlet to the basin slows the water and provides a slow even flow. The accumulation of these solids on the floor of the basin is called sludge. This system consists of plastic scraper boards attached to plastic chain on a continuous loop.