A sewer network is an interconnected system of underground pipes, manholes, lift stations, and drainage infrastructure designed to collect and convey wastewater and stormwater from residential, commercial, and industrial sources to treatment facilities. Within a GIS environment, sewer networks are modeled as topologically connected linear feature datasets, enabling precise spatial analysis of flow direction, pipe capacity, catchment delineation, and infrastructure condition assessment. Geospatial data layers representing pipe segments, node connectivity, elevation attributes, and asset metadata are integrated into geodatabases, allowing engineers and utility managers to perform network tracing, hydraulic modeling, and failure impact analysis with high accuracy. GIS technology supports the mapping of sewer infrastructure at various scales, facilitating regulatory compliance reporting, capital improvement planning, and emergency response coordination. By leveraging spatial analysis tools such as upstream/downstream tracing, catchment area modeling, and proximity analysis, GIS professionals can identify vulnerabilities, prioritize maintenance schedules, and optimize rehabilitation investments. The result is a data-driven approach to managing critical wastewater infrastructure that improves operational efficiency, reduces environmental risk, and supports long-term urban resilience planning.