Water and Waste- Water Treatment plant and system operators manage a system of machines, often using control boards to transfer or treat water. Waste- Water Treatment operators’ control, monitor and maintain the equipment and treatment processes in wastewater (sewage) treatment plants. They remove or neutralise the chemicals, solid materials and organisms in waste-water, so the water is not polluted when it is returned to the environment. These operators run the equipment and control the processes that clean and treat the water.