A sewer is an underground system designed to transport wastewater and stormwater away from homes and buildings. It helps prevent flooding and keeps communities clean by directing waste to treatment facilities. Sewers are typically made of pipes that connect to various drainage systems. There are different types of sewers, including sanitary sewers, which carry sewage from toilets and sinks, and storm sewers, which handle rainwater runoff. Proper maintenance of sewers is essential to avoid blockages and overflows, ensuring that they function effectively and protect public health and the environment.