Where are the sampling point(s) located for required sampling of turbidity in a community water system?

• A. At the water treatment plant entry only
• B. At the point(s) where water enters the distribution system, including all filter effluents
• C. Only at the reservoirs in the distribution system
• D. At the end user tap points in the community

Answer: (B)

The correct choice indicates that turbidity samples must be collected at the points where water enters the distribution system, which includes all filter effluents. This approach is essential because measuring turbidity at these locations provides critical insights about the water quality after treatment processes and before it reaches consumers.

Turbidity, which is a measure of the cloudiness or haziness of water caused by suspended particles, can indicate the effectiveness of filtration and other treatment methods. By sampling at the entry points to the distribution system, water treatment operators can assess whether the treatment process effectively reduced turbidity to acceptable levels. Additionally, monitoring turbidity at all filter effluents ensures that any variations in treatment performance can be identified and addressed quickly.

Sampling only at the water treatment plant entry would not account for any changes in turbidity that might occur as water travels through the distribution system, and measuring at reservoirs or end-user tap points would not provide adequate information about the treatment efficacy directly after filtration. Therefore, sampling at the specified locations ensures comprehensive monitoring of water quality throughout the distribution process.