What is the function of a gravel layer in a drain field?

The function of a gravel layer in a drain field is essential for the effective operation of an on-site sewage facility. Primarily, the gravel layer provides stability, promotes drainage, and supports the distribution of effluent.

When wastewater is discharged into the drain field, the gravel facilitates the movement of liquids through the soil. It creates an aerated space that allows effluent to spread evenly across the drain field, preventing pooling and oversaturation in specific areas. This even distribution is crucial for promoting the natural breakdown of pollutants by microbial action in the surrounding soil.

Additionally, the gravel aids in maintaining the structural integrity of the drain field by supporting the weight of the system and preventing soil compaction that could hinder water flow. By ensuring proper drainage and promoting aerobic conditions, the gravel layer plays a vital role in the overall efficiency and longevity of the on-site sewage treatment system.

In contrast, while options like enhancing aesthetic appeal or reducing installation costs may be secondary considerations, they do not represent the primary function of the gravel layer within the context of sewage treatment, which emphasizes functionality and efficiency in wastewater management.