How do septic systems work to handle wastewater?

Septic systems work by managing wastewater through a two-part system: the septic tank and the drain field. Wastewater travels from the house into the septic tank, where it separates into three layers: a top scum layer of fats, oils, and grease; a middle layer of partially clarified wastewater, or effluent; and a sludge layer of solids at the bottom. Anaerobic bacteria in the tank break down the solid waste into simpler compounds, although periodic pumping is still needed for non-degradable solids. The effluent then flows into the drain field, which is a system of perforated pipes in gravel trenches. Here, the wastewater undergoes further treatment as it percolates through the gravel and soil layers, the soil acting as a natural filter to trap harmful constituents. The treated water, now significantly cleaner, returns to the groundwater system. Regular maintenance is required to ensure the system remains efficient and functional.