Which processes are used to remove particles from surface water?

• A. A series of treatment steps that are redundant in their ability to remove contaminants
• B. A single filtration method
• C. Chemical treatment only
• D. Only sedimentation

Answer: (A)

The processes used to remove particles from surface water typically involve a combination of treatment steps rather than relying on a single method. This integrated approach maximizes the effectiveness of the treatment process by utilizing various mechanisms to target different types of contaminants.

For instance, surface water treatment may begin with coagulation and flocculation, where chemicals are added to aggregate smaller particles into larger flocs that can be more easily removed. This is then often followed by sedimentation, where gravity helps settle out these bigger flocs. Lastly, filtration can further reduce the number of remaining particles, ensuring the water is clear and safe for consumption.

This combination of processes demonstrates redundancy in their ability to remove contaminants: if one method is less effective at capturing certain particles, other methods are in place to ensure overall removal efficiency. This multifaceted approach is essential for maintaining water quality and safety standards.