What is the recommended action before cleaning sewers?

Notifying downstream treatment plants and pump stations is crucial prior to cleaning sewers as it helps manage and prepare for any potential surge in flow or changes in water quality. When cleaning occurs, there may be an influx of debris, sediments, or other materials that could cause issues if not anticipated by downstream facilities. By alerting these facilities, operators can take necessary preventive measures, such as adjusting flow rates, ensuring that treatment processes are prepared for possible changes, or even temporarily diverting flows if necessary. This action ensures that there is a coordinated approach to maintaining system integrity and preventing possible overflows or disruptions downstream.

In the context of preparing for sewer cleaning, while gathering equipment and inspecting for blockages are essential proactive steps, they do not address the immediate need to prepare downstream facilities, which can help prevent operational issues during and after cleaning. Closing upstream valves might be necessary in specific circumstances, but ideally, this action should only be taken if there's a clear plan to manage the flow and impacts on the overall system, which is why notifying downstream facilities is more immediately critical.