For many, little thought is given to septic tanks. Well, that’s until a problem arises – the toilet won’t flush, there is sewage backing up the drains or there is a foul smell emanating from the outlets – it’s only then that we wonder what has gone wrong and the septic tank becomes notable in our minds.

While we recognise that it is important to maintain and take care of a septic tank, how many people could actually say that they know exactly how a septic tank works or how much one costs? Chances are that the results would be quite low.

For that reason, we’re going to shed some light on the subject – the following is a brief guide outlining how septic tanks work and what they cost.

The main Components of a Septic Tank

A septic tank system is made up of three components – the tank itself, the drain field and the soil. The tank itself can be made of fibreglass or plastic, both of which models are usually globe-shaped. Concrete septic tanks are also available and these are generally constructed in rectangular shapes. The cost of a septic tank will be dependent on the size of the tank being installed. However, in general terms, a standard sized septic tank will come with a price tag of approximately €800.

Step 1 – In the Tank

In the first instance, wastewater enters the septic tank through the pipelines leading from your property. While sitting in the tank, the solids and the liquids that make up the wastewater begin to separate (with the solids sinking to the bottom forming the sludge layer and the lighter particles of waster rising to the top, forming a layer known as scum). The sludge is left behind and eventually begins to build up which is why a septic tank must be emptied every few years.

Step 2 – The Drain Field

The wastewater, now comparatively free of solid waste and known as effluent, then flows into another chamber in the tank. Here, due to pressure in the tank caused by the incoming wastewater in the main tank, the effluent flows out into the drain field through a series of perforated pipes. Once the effluent flows out through the pipes, it then flows through a layer of gravel before it finally reaches the soil.

Step 3 – The Soil

This is the last stage of the septic tank process where the biological organisms in the soil treat the waste ensuring that it permeates down and eventually out of the soil, joining up with the water on the surface. This stage is probably the most important as it ensures that the waste is no longer a health or environmental hazard which is why extensive soil testing is carried out prior to a septic tank installation to ensure that the soil is suitable.

Having some knowledge of the mechanisms of your septic tank could serve you well in the case of problems arising from its malfunction. Your septic tank works hard so make sure that you give it the maintenance and care that it needs to last and function properly.