The Evolution of an Inspection Program: How the Washington Suburban Sanitary Commission's Trunk Sewer Program Has Evolved and Expanded Over a Decade

In 2005, WSSC Water entered into a Consent Decree with the United States Environmental Protection Agency (EPA), Maryland Department of the Environment (MDE) and Citizen groups in response to Sanitary Sewer Overviews (SSOs) in WSSC Water’s wastewater collection system. Among the requirements of the Consent Decree was the development of a dedicated Trunk Sewer Program, focused on the inspection, condition assessment and evaluation of WSSC Water’s sanitary sewers (15-inches and larger in diameter), appurtenances and stream crossings. This paper will serve to provide a high-level overview of the history of WSSC Water’s Trunk Sewer Program and regulatory requirements, and will discuss the Program’s evolution over the past 12 years, including the expansion of the Program’s scope and key technologies that have been implemented to support WSSC Water’s efforts to most effectively manage their trunk sewer assets, meet (and exceed) the requirements of the Consent Decree, and support the overarching goal of WSSC Water to provide best in class utility services to their customers.