What is the final step in removing suspended matter from water?

The final step in removing suspended matter from water is filtration. This process involves passing the water through a filter medium, which can vary from sand and gravel to advanced membrane technology. During filtration, suspended particles that have not settled during previous treatment stages, such as coagulation and clarification, are trapped in the filter material, resulting in clearer water.

Coagulation is an earlier stage where chemicals are added to the water to help bind smaller particles together into larger aggregates, which then can be removed more easily. Clarification comes after coagulation and involves allowing these aggregates to settle out of the water column. However, while both coagulation and clarification are crucial steps in the water treatment process, they do not complete the removal of all suspended matter; filtration is essential for this final stage.

Disinfection, on the other hand, is a different process that typically follows filtration. This step involves killing or inactivating harmful microorganisms in the water, ensuring that it is safe for consumption. Therefore, while disinfection is critical in the overall treatment process, it does not specifically address the removal of suspended solids, which is the focus of this question.