Exfiltration in sewer systems refers to water that does what?

Exfiltration in sewer systems refers to water that does what?

• A. Leaves the sewer into the surrounding ground
• B. Enters the sewer from groundwater
• C. Flows within the sewer pipe only
• D. Evaporates before treatment

Answer: (A)

Exfiltration means wastewater leaking out of the sewer into the surrounding ground. This happens when pipes or joints are cracked or degraded, allowing liquid to escape the sewer and migrate into soil or groundwater. It’s the opposite of infiltration, which is groundwater entering the sewer through cracks or leaks. So leaving the sewer into the surrounding ground is the correct description. The other scenarios don’t fit exfiltration: water entering from groundwater is infiltration, flow inside the pipe is just normal conveyance, and evaporation is loss to air, not into the surrounding ground.

Exfiltration means wastewater leaking out of the sewer into the surrounding ground. This happens when pipes or joints are cracked or degraded, allowing liquid to escape the sewer and migrate into soil or groundwater. It’s the opposite of infiltration, which is groundwater entering the sewer through cracks or leaks. So leaving the sewer into the surrounding ground is the correct description. The other scenarios don’t fit exfiltration: water entering from groundwater is infiltration, flow inside the pipe is just normal conveyance, and evaporation is loss to air, not into the surrounding ground.