Inflow is stormwater that enters the sewer system through rain leaders, basement sump pumps or foundation drains illegally connected to the sewer. Together, inflow and infiltration place a burden on collection systems and wastewater treatment facilities.

Jun 20, 2022 · Inflow and Infiltration, commonly referred to as I&I, is excess water flowing into your sanitary sewer system. Inflow is typically a form of stormwater runoff from existing grade that gets into the sewer system, usually from cracks inside the manhole or damage to the manhole chimney, frame, or cover.

Here are six ways to proactively identify inflow and infiltration (I&I), including signs it may be lurking. Each of the tactics below are effective, but the appropriate approach for your efforts depends on the challenges at hand, the state of your infrastructure, the …

Sewerage (or sewage system) is the infrastructure that conveys sewage or surface runoff (stormwater, meltwater, rainwater) using sewers. It encompasses components such as receiving drains, manholes, pumping stations, storm overflows, and screening chambers of the combined sewer or sanitary sewer.

Apr 5, 2025 · Infiltration and inflow (I/I or I&I) is the process of groundwater, or water from sources other than domestic wastewater, entering sanitary sewers. I/I causes dilution in sanitary sewers, which decreases the efficiency of treatment, and may cause sewage volumes to …

Jan 1, 2021 · Stormwater flowing into a municipality’s sewer system through low gully traps, illegal connections, broken pipes, and unsealed manholes can cause overflows, system strains, and interruptions in your sewer operations. This is known as Inflow and Infiltration; aka I&I. Why bother to fix Inflow & Infiltration?

King County is working with our local sewer agencies to reduce and prevent infiltration and inflow (I/I) in our separated sewer system. Our I/I Control Program helps protect the environment by maintaining pipe capacity for what’s it’s meant to convey—sewage—and preventing …

Mar 23, 2025 · Aging sewer systems across the U.S. are facing increasing challenges due to infiltration and inflow (I&I) —two common yet costly problems that burden wastewater infrastructure, lead to environmental contamination, and increase treatment costs.

Inflow occurs when rainwater is misdirected into the sanitary sewer system instead of storm sewers. Examples are: roof leaders, footer drains, sump pumps, manhole covers, and cross connections from storm drains.

Inflow and Infiltration (I&I) are two major challenges facing wastewater systems, causing excessive water to enter the sewer system and creating various operational problems. When left unmanaged, I&I can result in overflows, increased treatment costs, and damage to infrastructure.