A septic system is an on-site wastewater treatment system commonly used in areas where centralized sewer systems are not available. It consists of a septic tank and a drain field (also known as leach field or absorption field). Here's how it works:
Septic Tank: Wastewater from toilets, sinks, showers, and laundry flows into the septic tank. Inside the tank, solids settle to the bottom forming sludge, while oils and grease float to the top forming scum. Bacteria break down the organic matter in the sludge and scum.
Effluent: The liquid wastewater, known as effluent, exits the septic tank and flows into the drain field through pipes or perforated distribution boxes.
Drain Field: The drain field consists of a network of perforated pipes buried in trenches filled with gravel or other aggregate. The effluent seeps out of the pipes and is filtered through the soil, where further treatment occurs as it is naturally purified.
Soil Treatment: Soil acts as a natural filter, removing harmful bacteria, viruses, and nutrients from the effluent before it reaches groundwater.
Different Setups:
Septic systems can vary based on factors such as soil type, site conditions, and local regulations. Some common variations include:
Conventional Gravity System: This is the most basic setup where wastewater flows from the house into the septic tank and then into the drain field by gravity. It relies on the natural flow of water.
Pressure Distribution System: In areas with high groundwater or poor soil conditions, a pump may be used to evenly distribute effluent to the drain field.
Mound System: If the soil is too shallow or has poor drainage, a mound system may be used. It involves constructing an above-ground mound of sand or gravel for the drain field.
Advanced Treatment Systems: In environmentally sensitive areas or where conventional systems are not suitable, advanced treatment systems may be used. These systems incorporate additional treatment processes to further purify the wastewater before it is discharged.
