Septic Tanks
Septic tanks first came into popularity during the 1800's in large country houses where the gentry found the smells from old style ‘privvies’ becoming unacceptable and were looking for more comfort at home.
Today, there are several laws governing the use of such tanks in order to prevent health or environmental problems from occurring. If you are unsure of the construction, design, or treatment standards of your tank or are considering replacing or installing one for the first time, contact your local government office to check that your system complies with the law.
As the owner or occupier of a property with a septic tank system, you have a legal responsibility to ensure that it functions properly. By following the ‘Do’s and Don’ts’ given below, you can ensure that you are getting the best from your system and minimise any potential problems. All active ingredients in soap and detergents are biodegradable by law and are safe for Septic Tanks in normal use. Please note that it is a legal requirement for a dishwasher or washing machine to be connected to a Foul Sewer or Septic Tank, not a surface drain. Because it is underground and out of sight, it is easy to forget about, or ignore, your septic tank. An improperly used or ill-maintained tank can pollute both surface and drinking water and lead to many problems. Below are some basic facts and tips to help you look after your tank.
All septic tanks must be installed to Local Authority standards and inspected by qualified personnel, regularly. Local Authorities can provide guidance on how frequently these inspections should be carried out.
How a Septic Tank Works
Septic tanks receive raw sewage from a property, which then separates into solids and liquids. The liquids (known as effluence) flow out, usually to a land drainage system.
Some of the solids float to the top of the tank where they form scum, including detergents, cooking fats, and other non-decomposable materials. The heavier solids remain at the bottom of the tank, where anaerobic bacteria (which doesn’t need oxygen to survive) produce methane and hydrogen sulphide and decompose them into a sludge layer. Inorganic materials such as plastic film, which neither floats nor decomposes should not be flushed down the toilet as it will only serve to block the pipes of the tank. The tank should be cleaned every 1 – 3 years, depending on its size and the amount of solids which enter it. The effluent emptied from the tank still contains a large amount of pollutants and therefore needs further treatment at a sewage plant.
The size of a septic tank will depend on the number of occupants of the property and the rate of water flow on the land. Consideration should be given to future possible expansion so that the tank does not become overloaded in later years. Before installing a septic tank system, check with your local government office as you will undoubtedly require permission for such an installation and it will be necessary to ensure the chosen site is suitable.
Do’s and Don’ts of Septic Tanks
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Warning
NEVER ENTER A SEPTIC TANK AS TOXIC GASES ARE PRODUCED BY THE NATURAL TREATMENT PROCESS. ENSURE ALL MAIN SEPTIC TANK COVERS ARE KEPT LOCKED AT ALL TIMES.

