Hydraulic Model Methodology for Evaluating Sewer Rehabilitation Projects

Sewer rehabilitation is an industry standard practice to reduce excessive infiltration and inflow (I/I) and to improve the performance of sanitary sewer collection systems. By implementing different rehabilitation methods, the general assumption is that the occurrences of sanitary sewer overflows (SSO) and excessive loads at pump stations and treatment facilities, will be reduced and adequate capacity provided for the design life of the rehabilitation project. Conventional methods for evaluating sewer rehabilitation projects use flow meter data at the major trunk lines or at treatment plants to determine the changes in I/I values between a pre-and post- rehabilitated system. This study demonstrates the methodology in using a dynamic hydraulic model (Model) to evaluate and analyze the changes in I/I due to the sewer rehabilitation projects within a sanitary sewer system.