Inflow & Infiltration (I&I) Reduction Program

Inflow and Infiltration – What you need to know.

Inflow and infiltration (I/I) is clear water – such as groundwater and surface water - that enters the wastewater system from sources such as defective sewer service laterals, poor pipe connections, sump pumps, gutters/downspouts, building drains, and aged or broken sewer main and maintenance hole covers. When clear water enters the wastewater system it needs to be treated at a wastewater treatment plant. During rain events, I/I adds significant amounts of clear water to the wastewater system that it was not intended to accommodate or treat.

Inflow is when clear water from illegal connections of sump pumps, downspouts, and foundation drains is channeled directly into sanitary sewer pipes.

Infiltration is when groundwater seeps into sewer pipes via cracks or leaky joints.

Inflow & Infiltration (I&I) Reduction Program 

Over the past several years the City has been working diligently to ensure the City’s sanitary sewer system is free of defects and operating properly. Additionally, the City is working to eliminate unnecessary ground water from entering our sewer system. User sewer rates are impacted due to the I&I expenses related to the maintenance and operation of pump stations, as well as increased potential for system back-ups.


The City has contracted with Northland Lining to televise sewer services in designated areas in the City. The contractor will contact designated homeowners to arrange a time to access into your home where they would inspect the sewer service from your house to the street and conduct the necessary televising to determine if there are any issues with your sanitary sewer service lateral. This entire inspection would take approximately one hour.  If there are any issues with the sanitary sewer service lateral, we would need to reschedule another time for the contractor to make the necessary repairs, or improvements. Contact Public Services @952-442-2615 or if you have any questions on the program.