What is a septic tank?
A septic tank system is basically a mini sewerage treatment facility on the grounds of your house or community building and is installed if the property is not connected to a working sewerage system maintained by the local municipality.
It is a container buried underground and made from plastic or concrete, mainly used for the disposal of sewerage and other waste water, which is stored and treated to become mostly harmless end-products. From there effluent moves into a French drain or soak pit so that it eventually drains away into the ground over time. If you are responsible for a development where a septic tank is being considered, check that the soil is suitable to house this installation.
What does it cost to install?
Depending on your choice of septic tanks, installation prices will vary: plastic septic tanks are watertight and completely resistant to corrosion, weigh much less than concrete or steel septic tanks and this makes them much easier to install. A steel tank can last between 15 or 20 years, whilst a concrete tank can be used for well over 40 years if properly maintained. Savvy Plumbing can make recommendations in this regard.
A contractor or builder will dig the space for the tank and system at the same time when the foundations for the building are being put in, with a minimum distance away of 3m.
What does this mean for you?
- No need to pay the monthly municipal sewerage charges and you can control the installation cost with your choice of system.
- The impact on the environment is far less than those instances where sewerage leaks into the ground or rivers due to lack of maintenance by local authorities.
- There is some maintenance to be done – one portion annually and another every few years.
How does a Septic Tank or French Drain work?
There are various components to the septic tank system, with each one having a specific function:
- Septic tank itself – untreated waste water from building flows into this.
- As a result of gravity, the liquid separates from the solid portions.
- Fat or soap scum in kitchen and bathroom waste water floats to the top.
- Human waste and other heavier solids, drop down to the bottom of the tank and are known as sludge.
- A by-product of the waste is bacteria and this helps all the content in the tank to break down.
- French Drain – once the waste liquid reaches a certain level, it flows into the French drain and thereafter slowly into a land drainage system/drain field/soak pit after some time.
Buying and maintaining a septic tank system
Use this general guide to the size of tank you may need:
No. of people | Ideal Tank Capacity | How often to drain |
1-4 | 1 500 L | Every 5 years |
4-6 | 1 750 L | Every 4 years |
7-8 | 2 000 L | Every 3 years |
8-10 | 2 500 L | Every 2 days |
More than 10 | 6 000 L | Annually |
- Speak to your local plumbing organisation or septic tank specialist to drain your septic tank every two to five years, depending on usage or the number of people in the household.
- It’s a good idea to have the sludge and scum layers measured annually, otherwise you could end up with clogging and leaks.
- It is important to note that you should only flush toilet paper and water down the toilet when you have a septic tank. All other items, including paper towels, sanitary products, condoms, cigarette butts, disposable nappies, food waste and non-biodegradable items must NOT be flushed down the system, but rather thrown out with rubbish. You WILL have problems if you ignore this basic rule!
- Check the wording on your industrial toilet cleaning product to see if it can be used safely – septic tanks are not chemical resistant.
- Make sure that the concrete top of the tank is not damaged or leaking, as liquids from the tank carry disease-causing germs.
If you notice any of the following, call a plumbing specialist right away:
a. Wet spots above the tank or sewerage that is coming to the surface.
b. Gurgling sounds in the plumbing system.
c. Basins, sinks and toilets that are draining away slowly.
Savvy Plumbing is part of the Boksburg-based Savvy Holdings Group, which has been around since 2012. Our experienced management and staff have collectively been in this industry for over twenty-five years, so you can be assured of knowledge, professionalism and technical know-how. Call us today on 087 806 6262 or email info@savvyplumbing.co.za or send us a message for help.