I & I Projects

Infiltration & Inflow Projects

As part of the City’s continuing efforts to reduce the amount of Infiltration and Inflow (I&I) into the City’s sanitary sewer system, a number of projects will be under construction throughout the city. These project range from large Capital Improvements to small repair and maintenance projects. 

What is I & I?

I & I stands for Infiltration & Inflow. Infiltration is groundwater that enters the sewer system through leaks in the manholes, sewer mains and sewer laterals. Inflow is storm water that enters the sewer system through surface drains and downspouts that are connected to sewer lines. I&I can contribute significantly to the cost of operation and capacity of the City’s water reclamation facility. These projects are a proactive approach to fixing deteriorated infrastructure prior to failure. This effort to reduce I&I began in the late 1990’s and is a key component to the City’s Treatment and Collections System Master Plan.

What to expect if an I & I project comes to your neighborhood

Construction will take place in the streets or resident’s back or side yards depending on the location of the sanitary system. Residents will be notified before work begins. For any work outside of the City right-of-way, the contractor will work with the resident regarding access, pets, or any other concerns.  Construction may require short-term interruption of service (typically just a few hours) for connection of the private lateral to the improved wastewater system. Some of the work requires accessing private property to reconnect or redirect the private sewer laterals.

What to expect after construction 

Following construction, each of the private sewer laterals in the project area will be evaluated. This process typically will take a few months. The private sewer laterals which fail inspection will receive a Notice of Defect letter from the City directing the property owner to replace or repair their private sewer lateral. Private sewer laterals can fail for a variety of reasons, or combination of reasons that range from type of material to defects in the pipe such as breaks, holes, roots and other imperfections that allow unwanted inflow and infiltration to enter the sewer system. If you receive a Notice of Defect letter, you may qualify for a reimbursement through the City’s Sewer Lateral Program. 

For more information regarding the City of McMinnville’s Sanitary                                                                                             Sewer Lateral Program view the document below.