Why does my septic system smell?
Causes of septic odours in AWTS sewage systems
Aerated wastewater treatment systems are an effective way of treating effluent to a secondary standard, which enables homeowners to reuse it for irrigation. Like for any sewage system, it is important to identify signs that indicate that there may be something wrong with the system, like emitting bad odours. There are many different reasons why your AWTS septic system is producing a foul smell, which is why it is important to understand these causes so that the problem can be fixed.
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. Each of these causes will be explained further below.
System bacteria health
AWTS sewage systems contain anaerobic bacteria which use oxygen to break down and convert organic waste to energy. Oxygen is supplied to the bacteria, through an aeration pump in the system, which helps the bacteria grow. If the bacteria population is not large enough, then the wastewater contaminants will not break down entirely, resulting in a terrible odour.
Exposure to household chemicals and waste products, such as; 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 in the effluent.
Filtration time
The time wastewater remains in the septic system can impact the smell of the effluent. In order for the treatment process to be effective, the sewage waste must remain in the system for a certain amount of time before it is ready to be reused. This period of time in the aerated system will allow for the bacteria to fully break down the waste matter, and complete the secondary treatment. If a home has a large quantity of wastewater entering the system in a short period of time, then the effluent will not be treated for long enough for it to be suitable for irrigation use, causing it to emit a foul odour.
Broken seals in pipes
If the seal of the pipes leading to the wastewater treatment system is broken, then odours may become noticeable. The shape of ‘u’ and ‘s’ bend pipes allow a segment of water to be trapped in the curve, providing the pipe with a water seal, which allows wastewater to flow through the pipes while eliminating the presence of any disgusting odours. 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.
What to do if you notice a bad odour coming from your sewage system?
To remove odours from blockages, use a natural solvent like baking soda and vinegar. This should remove the blockage and odour, while also not killing any of the good bacteria in the sewage system. Ensure that your anaerobic pump is working effectively so that the bacteria can continue to thrive. Although these methods can be done yourself at home, they will not always be effective at removing the odour from your sewage plant, so it is often best to contact a qualified professional.
Your local and professional sewage treatment plant service
Does your aerated sewage system smell bad? If you are looking for a specialist service for your home sewage treatment plant, then get in touch with Express Wastewater. We have a team of licensed professionals who have experience with a wide variety of treatment plants and are happy to offer you our services. To discuss a sewage treatment system for your home, call us at 1300 722 517 or complete our sewage system booking request form today.
Resources
https://www.waternsw.com.au/water-quality/catchment/living/wastewater/systems/awts
https://ecocare.com.au/content/why-does-my-septic-smell
https://www.hunker.com/13429466/how-to-add-good-bacteria-to-a-septic-tank