The answer to 'how does septic tank work' is that a septic system is an onsite wastewater treatment system that uses a septic tank and a drain field to treat and dispose of household wastewater. The septic tank is a buried, water-tight container that receives wastewater from the home. The tank allows solids to settle to the bottom, where bacteria break them down. The liquid wastewater then flows out of the tank and into the drain field, where it percolates through the soil and is further treated.
The septic tank needs to be regularly pumped and maintained to ensure it continues to function properly. Proper use and care of the septic system is important to prevent expensive repairs or replacement.