News Flash

Crews are taking advantage of rainy weather, as it provides the best conditions to measure and understand how much stormwater is entering the city’s sewer system – known as inflow and infiltration, or I & I. Because of this, crews are using these rainy days to track and measure how successful the City’s I & I Program has been at reducing I & I.  

Each year, monitoring equipment (i.e. flow monitors) are placed in selected manholes to measure and compare current levels with pre-rehabilitation I & I project levels. Last year’s results showed a 30% reduction in I & I within completed project areas, confirming that recent improvements are working as intended –  reducing the amount of rainwater from entering the sewer system.  These results help plan future projects for construction. 

In addition to system monitoring, several active I & I projects are focused on lateral pipe investigations.  Lateral pipes are the smaller, privately owned sewer lines that carry wastewater from homes and buildings to the main public sewer line.  Two projects (Linn Basin Project 2 and McLoughlin Basin Project 1) are currently conducting lateral investigations to identify sources of inflow from lateral lines in preparation for mainline sewer and private lateral repairs planned for early next year. These proactive efforts will further reduce stormwater entering the system, support long-term system reliability, and prepare the I & I program for continued progress as new projects move forward.