How often are surface supplies sampled for chemical analysis?

In the context of water supply management, particularly for surface water sources, the standard practice for chemical analysis sampling is typically once a year. This frequency strikes a balance between ensuring that the water supply's chemical characteristics are monitored effectively while also managing resources and laboratory workload.

Sampling once annually allows for sufficient data collection to identify any changes or trends in water quality due to seasonal variations or other environmental factors. This timeline is supported by guidelines set forth by regulatory authorities, which emphasize the importance of consistent monitoring without overwhelming treatment facilities and laboratories with excessive sampling demands.

Other sampling frequencies might seem appropriate, but they either do not align with standard practices or may be too infrequent to adequately assess potential chemical changes in the water supply.