How does a Septic System work?

A septic system is installed to treat and recycle wastewater from houses and businesses when there is not a connection to a public sewage treatment works. The system collects, stores, treats, neutralizes, and stabilizes all sewage that occurs on the property.

The term “septic” refers to the anaerobic bacterial environment that develops in the tank which decomposes or mineralizes the waste discharged into the tank.


Septic System Parts:

Sewer Line with clean out: When the plumbing is installed in a house or business, all pipes lead into one pipe that exitsSeptic system, house sewer pipe, Bio-Gard the house and connects to the septic tank. This pipe has a cleanout (vertical pipe with removable lid) installed in it for easy servicing of the pipe.


Septic System, Bio-GardTank: A septic tank generally consists of one tank (can be more than one tank) between 1,000 and 2,000 gallons in size. The tank is connected to a sewer line from the house, and the effluent (exiting treated water) drains or is pumped into the drain field. Inside the tank(s), the sewage settles into three layers: the sludge on the bottom of the tank, the effluent in the middle, and the scum layer on top. The tank is typically sub-divided into compartments that allow for settling of solids and filtration of the effluent before releasing to the drain field.


Septic Tank Riser, Bio-GardTank Riser: Added to the top of the openings on septic tanks to bring opening to grade (level with surrounding ground). This allows for easy service of the tank and prevents the tank from completely being covered with soil and vegetation.


Drain field, leach lines, septic system, Bio-GardDrain Field: Also known as the leach field, its purpose is to remove contaminants and impurities from the liquid that emerges from the septic tank. Older system drain fields are 4 inch perforated pipe surrounded by small rock buried below the soil freeze line of the area. The stones and soil act as filter removing nutrients and microbes from the effluent.


Distribution box: Is a box, typically concrete, that is connected to the exiting pipe from the septic tank. The purpose of Distribution Box, Septic System, Bio-Gardthe box is to evenly distribute effluent to each of the lateral pipes in the drain field. The number of lateral pipes in the D-Box are dependent upon the size of the needed to treat the home or business.


Gravity Filter, Septic System, Bio-GardFilter:  Installed inside the tank, either in the exit “T” valve, or attached to the pump that moves effluent to the drain field. The purpose of the filter is to prevent sewage sludge particles from leaving the tank with the effluent and contaminating or clogging the drain field.