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  4. Why Does My Septic System Smell?

Why Does My Septic System Smell?

If you live in an area not connected to the municipal sewer system, you'll need a septic system to manage your household wastewater. There are two methods for residential septic wastewater treatment: the traditional septic tank and the aerated wastewater treatment system. (AWTS) When you rely on a septic system you will be well aware of how important it is to keep it in good condition, health and working order. So if you notice a horrible odour coming from your system regardless of which method you have it is important to identify what is causing the problem. If your septic system is functioning properly and free of issues it will not release any unpleasant odours.

diagram of man pinching nose to block smell

 

Key Differences between Aerated and Traditional Septic Systems

  • Aerated systems use oxygen to accelerate treatment, while septic systems rely on natural processes without air.
  • Aerated systems generally provide more effective treatment, especially in areas with stricter wastewater discharge regulations.
  • Aerated systems require more frequent upkeep than traditional septic systems.

How a Traditional Septic System Works

A traditional septic system uses a septic tank to collect household wastewater and a drain field to treat and filter out all impurities. Any solid waste settles in the tank, while the liquids flow into the drain field for natural filtration through the soil. This method relies on natural anaerobic bacteria which works without oxygen to break down solids in the tank.

Reasons Your Septic Systems Smells

If you notice persistent unpleasant odours, emitting from your septic system, it's important to have your system inspected by a wastewater expert to identify and fix the issue. If left the problem may escalate unaddressed you may need Reasons include:

  • Clogged or Full Septic Tank - When a septic tank becomes too full or clogged, it can't properly process waste, causing odours to escape from vents or drains.
  • Poorly Maintained Tank - Without regular pump outs or maintenance, solids and sludge accumulate, leading to bad smells as they decompose.
  • Inadequate Ventilation - If the vent pipe that allows gases to escape is blocked or malfunctioning, it can cause sewer gases to back up and release into the house.
  • Leaking or Damaged Tank - Cracks or leaks in the septic tank can allow sewage to escape into the soil, leading to foul odours around the system.
  • Clogged Drain field or Absorption Area - When the drain field or absorption area becomes saturated or blocked, sewage can back up, resulting in unpleasant smells around the system.
  • Organic Material Decomposing - The natural breakdown of organic waste in the tank releases gases like hydrogen sulphide, which has a distinct rotten egg odour.
bacteria in wastewater

 

Reasons your Aerated Wastewater Treatment System Smells?

The main causes of a bad smell in an aerated wastewater treatment system are; the health of the system's bacteria, time the wastewater spends in filtration, disposal of foreign solids into a wastewater system, broken seals in pipes and blocked drains.

  • System bacteria health - AWTS sewage systems contain anaerobic bacteria which rely on oxygen to break down and convert organic waste to energy. Oxygen is supplied to the bacteria, through an aeration pump in the system, helping the bacteria grow. If the bacteria population is not large enough the wastewater contaminants will not break down entirely, resulting in unpleasant odours.
  • Exposure to household chemicals - Detergents, drain cleaning agents, grease, oil, fat and toilet paper, can kill the anaerobic bacteria in a sewage system. Also, a lack of oxygen supply can significantly reduce the bacteria population, preventing it from being able to break down septic waste. This in turn produces foul odours
  • Filtration time - The time wastewater remains in the septic system can impact the smell. Sewage waste must remain in the system for a certain amount of time before it is ready to be reused. This allows the bacteria to fully break down the waste matter,and complete the secondary treatment.
  • Broken seals in pipes - If the seal of the pipes leading to the wastewater treatment system is broken, then odours may become noticeable. If the seal of a pipe connected to your wastewater system is broken, then odours from the treatment system will be released into your home.
  • Blocked drains - If a drain connected to your wastewater system is blocked, then it will prevent sewage waste from entering the system. If the waste is left to sit in the pipes with no proper seal, then sewage odours will be emitted.

Resources

https://ecocare.com.au/content/why-does-my-septic-smell

https://www.hunker.com/13429466/how-to-add-good-bacteria-to-a-septic-tank