SEPTIC SYSTEM BASICS
In many small communities where there is no access to public sewers the on-site septic system is the best choice for processing household waste. Septic systems are generally simple in design and inexpensive to install and maintain.
The components of a typical septic system are:
The Septic Tank
This is where solids are processed and collected until pumped out. A septic tank may consist of one or two compartments. A two compartment tank consists of a side that holds solids and a liquid effluent holding side. Depending on design the liquid holding tank may contain a pump.
Septic system design varies greatly according to local regulations and customs. Your system may have a distribution box which, true to its name, distributes effluent from the holding tank to the various trenches in the field. A system may only have one trench or a simple “T” fitting going to the drainage trenches.
Drain Field or Leach Field or Drainfield or Absorption Field
No matter what you call it, its function is to absorb effluent and treat it to remove viruses and pathogens before returning the water to the surrounding soil where it is further filtered before reaching the water table. The field is usually constructed of lateral trenches filled with gravel. Drainage lines consisting of perforated pipe are placed on the gravel bed and covered with filter cloth and more gravel before covering with a layer of topsoil.
There are different types and designs of septic systems and almost all of them rely on the ability of the soil to absorb water.