What is a Drainfield?

Conventional Systems, as shown in this picture, is where liquid wastewater from the middle third of the septic tank exits the tank and is spread evenly throughout the drainfield.  Once in the drainfield, the wastewater percolates into the soil, which reclaims the water for future reuse by naturally removing harmful bacteria and some nutrients.

A properly sized drainfield is in the upper soil profile which is a friendly environment for the aerobic bacteria that treat our wastewater.  Additionally, there is an unsaturated zone of separation from the drainfield to the seasonal high-water table.  It has been established that when we percolate wastewater through unsaturated soil, we can discharge the treated wastewater into the groundwater which either recharges our groundwater aquifers or eventually discharges into our streams and lakes after proper treatment.

septic system and drainfield