GIS-Based Sewer System Inspection and Maintenance

Many cities in the United States are dealing with regulatory enforcement actions for sewer overflows, such as consent orders and consent decrees. These communities must comply with various mapping, monitoring, inspection, and rehabilitation requirements and develop and implement sewer overflow control plans. To comply with the regulatory requirements, the cities are collecting massive amounts of data on the inventory and condition of their sewer system infrastructure. A dilemma that all stakeholders are facing is how to cost effectively manage this data and monitor what has been accomplished versus what still needs to be done. Geographic Information System (GIS) is a cost-effective technology to manage and analyze these datasets. Above and beyond the conventional GIS mapping of inspection data, integration of field inspection data with GIS allows development of a sewer rehabilitation decision support system that can be used to plan the rehabilitation work required to control the sewer overflows. The recent implementations have demonstrated that application of GIS-based approach can result in a 20-30% reduction in project management labor effort over traditional methods. With the help of examples and case studies, this paper will describe a GIS-based sewer system inspection and rehabilitation approach.