Septic systems, or more accurately ‘Household sewerage treatment facilities’ are a source of mystery and bemusement to many householders.
What do I need to do with it? What can and can’t I put down the drain? How often do I need to get it pumped out? These are the types of questions we get asked frequently.

The mechanics of a septic system are usually fairly simple and very efficient. With proper care and maintenance a septic system will last for many years, and really they’re nothing to be scared of!

So this week we’ll try to give you an understanding of how the thing actually works, and give you some useful hints and tips of how to take good care of it in the next post

  1. Understanding how septic systems work

Your septic system has two major parts: a septic tank and a soil absorption system
Friendly bacteria in the tank decompose the ‘Fresh Produce’, this is the first stage of treatment and breaks the solids down to a liquid for transfer to the drain field for final treatment. The bacteria are not 100% efficient and the tank will need to be pumped out periodically to maintain efficient operation, this is usually at 3-5 year intervals depending on usage.
The Septic Tank
septic tankWastewater from toilets, showers, sinks and laundry flow through a sewer drain to an underground septic tank.

The relatively clear layer of wastewater that is left after the bacteria in the tank have done their job is called effluent. Effluent flows from the septic tank outlet to the soil absorption system where most of the treatment process occurs.


The Soil Absorption System


septic trenchThe soil absorption system, also known as the disposal field or ‘rubble trench’ usually consists of gravel-filled trenches containing perforated plastic pipe. This underground section of the system is connected the septic tank outlet pipe. Effluent moves through the pipes and is dispersed evenly amongst the rubble or gravel for final treatment. These pipes should be cleaned and inspected yearly by a professional contractor to ensure that the perforations don’t clog up.

Another type of bacteria live in on the surface of the gravel and rocks, these are the little guys that consume harmful microorganisms as the water trickles down through the layers gravel. Once the water hits the bottom of the drain field the soil particles filter out small suspended solids and organic matter, and the now treated effluent continues its downward journey through the soil layers.

Caring for your septic system

Taking proper care of your septic is an ongoing process, with care and correct maintenance your system should last for many years. They are a simple and efficient way to dispose of the amount of wastewater that the typical household generates

We will go into more detail on the Do’s & Dont’s of living with a septic system but understanding how they work is useful knowledge for any rural or semi-rural homeowner

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