This basic online course is intended for operators, maintenance personnel and managers of wastewater lagoon treatment facilities. Users will learn about sewage treatment lagoons including types of lagoons, the structural components of lagoons and lagoon systems, the biological stabilization process occurring in lagoons, and will be able to explain the routine inspection and maintenance activities, explain the frequency and use of analytical and performance measurements, recognition and correction of operation issues, and will be able to perform mathematical calculations related to lagoons and become acquainted with the safety issues related to operation and maintenance of lagoon systems.