Hydraulic modeling involves using a computer program to accurately predict the flow characteristics of wastewater through the pipelines of a sanitary sewer system. Weaknesses within the system are located by running simulations of design storm events (typically 5- or 10-year events) through the model to estimate the system’s reaction to increased flows due to inflow and infiltration (I/I). To calibrate the model, engineers use flow data collected from strategic locations within the collection system.