Dennis Cantrell, P.E. from HNTB explained the importance of unintended storm water leakage into the separate sanitary sewer system, and how the removal of the stormwater will improve the performance of the sewers in the Northland as part of Kansas City's Overflow Control Plan. Dr. Deb and Dennis explained what engineers mean when they refer to I/I (infiltration and inflow). Infiltration seeps into the sewer system through cracks and poor pipe connections, while inflow comes from roof or basement drains connected to the sewer system.