Inflow and Infiltration

Inflow and Infiltration is the term used when groundwater or storm water that should be makes its way into a sanitary sewer, where it does not belong.

Inflow is stormwater that enters the sanitary system through private property connections instead of the storm sewer such as down spouts, sump pumps, or foundation drains that are connected to the homeowner’s sanitary system

Infiltration happens when groundwater enters the sewage system through damage or defects such as holes or cracks in manholes or sewer pipes.

What can you do to prevent I&I?

Ensure your home’s downspout is disconnected from the sanitary sewer system and flowing properly towards the storm sewer
Ensure sewer grates on your street are free from debris such as leaves and garbage to ensure storm water drains properly
Use a rain barrel

The infographic below explains the difference between an incorrect and properly connected downspout.