Infiltration occurs when groundwater seeps into sewer pipes through cracks, leaky pipe

joints and/or deteriorated manholes. Inflow is stormwater that enters the sewer system

through rain leaders, basement sump pumps or foundation drains illegally connected to

the sewer. The impact on treatment and maintenance costs is substantial, and many

wastewater crews prioritize identifying and mitigating sources of inflow and infiltration

(I&I) in their systems.

Take this quiz to test yourself on how much you know about inflow and infiltration. Then

challenge your co-workers to see who will rise as the I&I expert.