What is the purpose of the septic tank in a septic system?

The purpose of the septic tank in a septic system is to treat wastewater by allowing solids to settle. In a septic tank, wastewater from the home enters and undergoes separation. Heavier solids settle to the bottom, forming sludge, while lighter materials, such as grease and oil, float to the top, creating a scum layer. This separation process is crucial because it helps reduce the volume of solids that eventually move into the drain field, allowing for more efficient treatment of wastewater.

The design of the septic system relies heavily on this settling process to ensure that the effluent, or liquid waste that flows from the tank, is relatively clear and contains fewer contaminants before it is discharged into the drain field for further treatment and absorption into the soil. This function is vital for maintaining the integrity and performance of the entire septic system and preventing groundwater contamination.