What is a septic system and how does it work?

What Is A Septic System?

A septic system is an underground wastewater treatment structure, used in rural areas without centralized sewer systems. It consists of a septic tank and a drain field.

The Septic Tank

The septic tank is a watertight container that holds wastewater from the household. Wastewater flows into the tank where solids settle at the bottom, forming sludge, while oils and grease float to the top as scum. The tank’s design allows the middle layer of liquid (effluent) to flow out into the drain field, while the sludge and scum remain in the tank. Bacteria in the tank partially decompose the solid waste.

The Drain Field

The drain field, or leach field, is a shallow, covered excavation made in unsaturated soil. The effluent from the septic tank is released into the drain field through a network of perforated pipes. The soil in the drain field filters and purifies the effluent as it percolates through the soil layers, removing harmful bacteria, viruses, and nutrients. Cleaned water eventually percolates into groundwater or evaporates.

Maintenance

Regular maintenance is crucial for the longevity and proper functioning of a septic system. This includes periodic inspection, pumping of the septic tank to remove accumulated sludge and scum, and avoiding overloading the system with excessive water or harmful chemicals.

Environmental Impact

A well-maintained septic system can effectively treat wastewater for many years. However, if not properly maintained, it can fail, leading to groundwater contamination and health hazards.