What is meant by infiltration in the wastewater collection system?

Infiltration in the context of a wastewater collection system refers specifically to groundwater entering the sewer system through various openings, such as holes, cracks, or other structural failures in the pipes or manholes. This process can lead to increased flow within the sewer system, which may overwhelm the capacity of treatment facilities, increase operational costs, and potentially lead to environmental issues such as overflows or untreated discharges.

Understanding the significance of infiltration is crucial for managing a wastewater system effectively. It helps in identifying and addressing vulnerabilities in the infrastructure to minimize unnecessary inflow of groundwater, which can dilute wastewater and lead to inefficiencies in treatment processes. This makes monitoring and maintenance critical aspects of wastewater management practices.

The other concepts are related to water flow in the system, but they describe different phenomena. Surface runoff typically refers to water from precipitation flowing over the ground rather than entering through the sewer system. Treated water released back into the environment indicates the final stage of wastewater treatment, not the entry of extraneous water into the system. Excess water from customer use relates to the volume of wastewater generated by users, which is different from infiltration, as it does not involve the unintentional addition of groundwater into the collection system.