Which issue causes the greatest volume of infiltration into the wastewater collection system?

Which issue causes the greatest volume of infiltration into the wastewater collection system?

• A. Residential sump pump discharges tied into the sanitary sewer
• B. Faulty house sewers
• C. Faulty joints in trunk sewers
• D. Crushed sections of sewer lines

Answer: (C)

The issue that causes the greatest volume of infiltration into the wastewater collection system is faulty joints in trunk sewers. This is because trunk sewers are the main conduits that transport wastewater from various areas to treatment facilities. When the joints between sections of these large pipes become damaged or faulty, they create openings through which groundwater can seep into the sewer system. This infiltration can significantly increase the flow of water through the sewer system, especially during periods of heavy rainfall or when the water table rises. The additional water from infiltration can overload the treatment facilities and lead to various operational challenges, such as reduced treatment efficiency, the need for increased capacity, or even the risk of sewer overflows. While other options like residential sump pumps discharging into the sanitary sewer, faulty house sewers, and crushed sections of sewer lines can contribute to infiltration or inflow, they typically do not produce the same volume as the infiltration occurring through faulty joints in trunk sewers, which are larger and often under higher pressure, enhancing the potential for significant groundwater intrusion.

The issue that causes the greatest volume of infiltration into the wastewater collection system is faulty joints in trunk sewers. This is because trunk sewers are the main conduits that transport wastewater from various areas to treatment facilities. When the joints between sections of these large pipes become damaged or faulty, they create openings through which groundwater can seep into the sewer system.

This infiltration can significantly increase the flow of water through the sewer system, especially during periods of heavy rainfall or when the water table rises. The additional water from infiltration can overload the treatment facilities and lead to various operational challenges, such as reduced treatment efficiency, the need for increased capacity, or even the risk of sewer overflows.

While other options like residential sump pumps discharging into the sanitary sewer, faulty house sewers, and crushed sections of sewer lines can contribute to infiltration or inflow, they typically do not produce the same volume as the infiltration occurring through faulty joints in trunk sewers, which are larger and often under higher pressure, enhancing the potential for significant groundwater intrusion.