Below are answers to the most frequently asked questions we get asked about septic systems.
1. Does my septic tank need to be completely buried?
Yes. Septic tanks must be buried.
Apart from this, septic tanks must have an access opening capable of being extended to ground level as well as an inspection opening. This makes it easy to conduct maintenance regularly. Additionally, the access opening must be watertight to prevent water (e.g. groundwater and stormwater) from entering the septic tank.
2. How deep can my septic tank be buried?
Coerco poly septic tanks are not to be buried more than 500 mm beneath ground level surface. This is because Coerco septic tanks are engineered and tested to be buried no more than the said depth.
3. How do I determine the size of my septic tank?
Generally, a smaller household of, say, 3 bedrooms, will need a smaller septic tank compared to a household with 5 bedrooms. Below is a table to help you determine septic tank size (or capacity).
4. What length of leach drain do I need?
The length of your leach drain is determined by the type of soil and the number of bedrooms in your house. Requirements from the Department of Health are outlined in the table below. These requirements can vary depending on individual council stipulations.
5. Should a septic tank and leach drain be trafficable?
Coerco septic tanks aren’t trafficable. However, an engineered cover above the buried tank and an access opening can be installed.
On the other hand, Coerco leach drains can be configured to be trafficable by reinforcing them with more internal panels.
However, the Department of Health does not allow for leach drains to be installed in trafficable areas. Vehicles are too heavy and could damage pipes, not to mention compact the soil and compromise evaporation. Oxygen also helps the soil around the drain field/ leach field to break down waste, but concrete or asphalt only serves to impede oxygen and further reduce waste breakdown by microorganisms in the soil.
Septic tank cover slab.
6. How often should my septic tank be pumped out?
A septic tank may be pumped out every 2 to 5 years. However, this can vary depending on the amount of solid wastes in your tank and the number of people in your household.
For example, a two-person household may require desludging every 8 years.
Apart from this, annual inspection should be done to check for any damage.
If you’re not sure whether your septic tank needs pumping, you can have it inspected by a certified pumper near you and then get advice as to when (or how often) you should get your tank pumped again. You can even record this data on paper to make sure you don’t forget.
7. How do I know that my septic system is failing?
The most common reason for a malfunctioning septic system is a lack of maintenance. For instance, if your septic tank hasn’t been pumped out for many years, it could likely be full of sludge which can clog up the pipes.
See here for signs that a septic system is not working properly.
8. How can I avoid septic system failure?
A properly designed and correctly installed septic system is a must. After installation, regular maintenance is key to ensuring that your septic system lasts a long time.
As a rule of thumb, items that do not decompose easily (this includes food, cotton, plastic, etc.) must not find their way in as they can cause clogging.
9. Who do I call to de-sludge or inspect my septic system?
Only certified pumpers must de-sludge your septic tank and inspect your entire septic system, including the leach drain. Your local health district or health department may be able to provide you with a list of certified pumpers.
10. Do I need additives/chemicals?
The biological material needed to break down waste is already in the waste itself. For as long as your septic system is well-maintained and not misused, there is no need for additives or chemicals.