Stormwater ingress to a city’s sewer system through low gully traps, illegal connections, broken pipes or unsealed manholes is known as Inflow and Infiltration (I&I). This can cause overflows, system strains and interruptions.
What is Inflow & Infiltration? Inflow: Stormwater that enters the wastewater network directly through gully traps, roofs or illegal connections. Infiltration: Stormwater or groundwater that enters the wastewater network through cracked pipes and leaky or faulty manholes.