The working principle of the Effluent Treatment plant(ETP) is undertaken to be one of the most effective principles used in an Effluent Treatment plant(ETP) where a large amount of human-friendly chemicals is used that are applied to the water to make it free from all the factors that might be harmful to humans and aquatic life. This is an important part of ETP that can be highlighted that helps to highlight that the working principles vary in several ways, furthermore, with the service of the ETP plant.