When conducting PDI of a waste water system, when should the flow test be conducted in relation to the flood test?

The flow test should be conducted before the flood test when performing a Pre-Delivery Inspection (PDI) of a wastewater system. This sequencing is essential because the flow test helps to determine the capacity and efficiency of the system under normal operating conditions. Conducting the flow test first allows inspectors to assess whether the system can handle the expected flow without issues such as blockages or inadequate drainage.

By performing the flow test prior to the flood test, you gain valuable data about how the wastewater system behaves under flow conditions. The results from this test can help identify any potential problems that may arise during the flood test, where the system is subjected to increased water levels to evaluate its performance during extreme situations. This orderly approach ensures that the integrity and functionality of the system are verified step-by-step, allowing for proactive measures to address any deficiencies before pushing the system to its limits.

The flood test itself aims to ensure that the system can withstand conditions it may face in the event of heavy rainfall or similar scenarios. Therefore, the initial flow test can guide any necessary remediation before subjects, and the system is further tested with increased water exposure.