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Why do septic tanks smell?

If you have a septic tank on your property, you will know that they are great when they are working at 100%. However, when they are working at less than perfect, they need prompt attention, especially when they are smelling less than pretty.

Septic Tank Smell

This is why we have put together some information about why septic tanks smell and what you can do to fix it, as well as prevent further issues. Get in contact with us if you need more help.

Should your septic tank smell?

No! If your septic tank has an unpleasant smell coming from it regularly, there is something that you need to investigate. If the septic tank is working as it should, you should not be able to smell it the majority of the time. This may seem a little contradictory, considering the type of matter that is contained in your septic tank, but it’s true!

Other signs that commonly accompany a septic tank’s odour are:

  • Other fixtures around your home may be running slower than normal.
  • There may be liquid waste that has flowed over near the disconnector trap.
  • There are areas above the septic tank that are noticeably wet.
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Why do septic tanks smell?

There is a range of reasons why a septic tank can smell, including:

  • The septic tank is full or overflowing and requires pumping out.
  • The bacteria in the septic tank are not balanced.
  • A clogged drain may have caused a dry drain, which can cause gases to seep in.
  • The septic tank lid may not be sealed correctly, or the lid may have a hole.
  • The septic tank vent is covered.
  • The septic tank was not installed properly.
  • Unwanted items have made their way into the septic tank.

There are other reasons too, however, the above are the most common options that occur in residential septic tank systems.

What should you do if your septic tank smells?

The first step is to figure out what is causing your septic tank to smell and where the smell is coming from. Is it coming from the tank itself, the ground around it or outside in general? Once you have located the problem, try the following. If you are still having issues, call your local septic experts.

  • Pump out your septic tank: This is the most common course of action and assists a lot of the time. The awful smell that comes from a septic tank can mean the tank is simply too full, so pumping it out can ensure the odour disappears.
  • Clean the bottom of your septic tank: As your septic tank collects matter, a ‘crust’ forms and separates the sewage from the air (which is known as a scum blanket). This helps with the overall process however, over time, scum also collects on the bottom of the tank. This can cause bad smells, so always ensure the sludge at the bottom of your tank is cleaned when necessary.
  • Watch what you place down the drain: Some chemicals and other products can cause your septic tank to give off a bad smell, such as grease, antibiotics, paints and transmission fluid. So always ensure you are placing septic tank-friendly matter down the drain at all times to avoid nasty odours.
  • Check for a missing or blocked vent: If a septic vent is blocked, which can occur when homes are renovated or remodelled, this can cause a bad odour. Additionally, the bad smell can be caused by no vent at all which needs to be addressed ASAP. To figure out if a missing septic vent is a problem, the bad smell will usually occur after you’ve finished in the shower.
  • Check the location of your septic tank: Septic tanks are not suited for every location and, if they have been installed above the water table, ongoing problems will happen. Speak to a professional about this!
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What can you do to stop your septic tank from smelling?

There are a few things you can do to try and prevent your septic tank from putting out bad odours:

  • Use natural products when you are cleaning your toilet or products that are recommended by your local septic tank professional.
  • Do not allow foreign objects to make their way into the tank, including toys, nappies and sanitary products, as these can cause blockages.
  • Do not flush ‘flushable’ wipes or other ‘biodegradable’ wipe options, as they do not break down quickly enough for your septic tank process and can cause blockages.
  • Repair leaking and/or broken toilets as soon as possible.

Maintenance tips for your septic tank

If you have a septic tank, try a few of the below tips and tricks to help keep your septic tank working at 100% all year round:

  • Become familiar with your septic system, including how it sounds and smells when it is running normally. This allows you to identify problems quicker if they arise and hopefully avoid serious issues before they occur.
  • Avoid overloading your tank wherever possible.
  • Ensure the lid of your septic tank is properly fastened at all times.
  • Do not cover your septic tank with anything that will get in the way of access, such as dirt, concrete or mulch. You need to ensure you have full access to your tank at all times, but it is protected from others.
  • Finally, call your local professional or service agent if you are having any problems. They will be able to help you assess the situation and decide on the best course of action. Or give us a call and we can help!
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If you would like some more information about septic tanks, or you would like to speak to our team regarding having a septic tank installed, give Express Wastewater a call at 1300 722 517 and we can discuss your needs.

 

Resources:

Australian Government - Department of Health (The septic tank): https://www1.health.gov.au/internet/publications/publishing.nsf/Content/ohp-enhealth-manual-atsi-cnt-l~ohp-enhealth-manual-atsi-cnt-l-ch2~ohp-enhealth-manual-atsi-cnt-l-ch2.9

Government of Western Australia - Department of Health (Understanding Septic Tank Systems): https://www.healthywa.wa.gov.au/Articles/U_Z/Understanding-Septic-Tank-Systems

NSW Government (The Easy Septic Guide): https://www.olg.nsw.gov.au/sites/default/files/Easy-septic-guide.pdf

Wikipedia (Septic Tank): https://en.wikipedia.org/wiki/Septic_tank

South Australian Government (Maintenance of septic tank systems): https://www.sahealth.sa.gov.au/wps/wcm/connect/91200f04-89a8-4aaa-87d9-554f42dd793d/ph-factsheet-septic-tank-system.pdf?MOD=AJPERES&CACHEID=ROOTWORKSPACE-91200f04-89a8-4aaa-87d9-554f42dd793d-mMFZiuj

Noosa Council (On-Site Waste Water Facilities): https://www.noosa.qld.gov.au/downloads/file/1482/on-site-waste-water-facility-guidelines

Plumbing and Drainage Act (QLD): https://www.legislation.qld.gov.au/view/pdf/inforce/current/act-2018-017