What do absorption trenches do in a septic system?

Absorption trenches play a crucial role in a septic system by allowing effluent to be absorbed and treated by the surrounding soil. This process is vital for the proper functioning of the septic system, as it facilitates the natural filtration of wastewater. When effluent is discharged into the absorption trench, it seeps into the soil, where the microorganisms present break down harmful pathogens and organic matter. This treatment helps protect groundwater and prevents pollution.

The design of absorption trenches typically includes gravel or sand media that aids in distributing the effluent evenly. The soil acts as a natural filter, and its properties are critical in determining how effectively the effluent is treated. Therefore, this answer accurately describes the primary function of absorption trenches within the septic system.