Wastewater Collection · Problems and Repairs
What Is Inflow and Infiltration (I&I)?
Infiltration and inflow add water that the sanitary system was not meant to carry.
Infiltration is groundwater entering through defects such as cracked pipe, bad joints, leaking manholes, or faulty connections. Inflow is water entering more directly from sources such as roof drains, area drains, sump pumps, or open manhole covers. The two are often called I and I. Wet-weather flow trends, night flow, smoke testing, dye testing, CCTV, and manhole inspection help crews find likely sources. Extra water uses pipe, pump, and treatment capacity. It can increase run time, energy use, backups, and overflow risk. Not every rise during rain has one cause; many small defects across a basin can add up. Operators collect clear location and weather data so repair programs can focus on the areas with the greatest effect.
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Introduction to Wastewater Collection Systems
This page comes from the free course. It follows wastewater from the building drain through sewers and lift stations to treatment, one step at a time, with short knowledge checks and a certificate of completion.
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