Sanitary sewer is a specialized skill that involves the installation, repair, and maintenance of underground sewer lines and pipes that carry wastewater from homes, businesses, and public buildings to treatment plants. This requires knowledge of plumbing and electrical systems, as well as experience with heavy equipment, excavation, and trenching. Sanitary sewer workers must also have a thorough understanding of EPA regulations and safety protocols to ensure that they operate in compliance with environmental standards and avoid accidents or injuries on the job.