Sewage and effluent (wastewater) from homes contain parasites and microorganisms that cause diseases and environmental damage. The safe disposal of such effluent should be a priority for shrewd homeowners. Septic tank systems facilitate treatment and disposal of sewage and effluent in homes which are connected to a sewer system. Here are some fundamentals about septic tanks that homeowners must know. Approvals Since a septic tank installation project is sensitive, you must apply to a relevant agency such as your local authority or public health office.