Septic Tank Cleaning (Desludging)
17 million litres
liquid waste collected
All septic tanks need to be cleaned, emptied or ‘desludged’ by an EPA-accredited Vac Truck business, regularly.
The wastewater (sewage or “blackwater”) that enters your septic system from your home, includes a mix of inorganic and organic substances. Over time, this effluent settles out in the primary septic tank, with the solids settling on the bottom as a layer of sludge, the grease/scum floating to the top, and a central volume of liquid effluent and dissolved solids between these two layers.
Over time, the sludge and scum layers will build up in your system. When these layers reach more than two thirds of the total capacity, your tanks need to be desludged by an accredited liquid waste contractor.
- It may cause blockages on the inlet of your system
- Raw sewage can overflow from the Over Relief Gully (ORG), which is the black grate near the edge of house
- High sludge and scum levels may cause:
- Poor performance of the septic system
- Blockages within the septic system and/or irrigation filters
- Blockages within irrigation areas / trenches, causing costly repairs to the irrigation field
- Bad odours
- Blockages of pumps, causing costly repairs
On average, a family of 3-5 people should have their septic system desludged every three years.
Yes, you can. But we will need to expose the tanks before we can empty them. Additional costs may apply if we need to dig up tank and expose lids.
Harmor Liquid Waste Solutions utilise a number of different sized trucks to cater for site access to all systems/properties, but we need to organise the right truck ahead of time, so please let us know when you call to book this in.
If your system is more than 40 metres from where the truck can park, we will need to bring additional hose, which may incur an additional cost.
It usually takes up to three months for the system to re-establish the good bacteria and start producing clean odourless effluent. During this period, you may experience:
- Strong odours, especially during peak times such as showers and after loads of washing, etc
- Poor quality of treated effluent
- Service reports stating system poor performance
- Avoid or reduce any harsh chemicals being poured down the drain
- Conserve water usage
- Prevent oils and grease from entering your system. Put them in the rubbish bin instead.
- Refill the system with water immediately. The water helps to give your system a head-start by diluting the wastewater that enters your system. Refilling with water will also ensure there is sufficient weight in the system to prevent the unlikely, but possible, situation of your tank/s lifting out of the ground, due to buoyancy from groundwater pressure. This is especially the case during wet weather or in high-water table areas, and especially for plastic tank systems. Be careful to closely monitor whilst refilling the system, don’t forget to turn off the tap. You can refill the system by putting hose through the septic access lid or down the ORG (100mm black grate on the outside of your house)
- Advise Harmor of the date of your desludge so we can update your records for future reference.
Please note: Strong medications can also affect the re-establishment of good bacteria in your septic system. Contact Harmor if you would like more information about this.
There are different types of septic systems which can come in all different shapes and sizes, depending on the property type, size, location and distance to local waterways.
Over the years, ALL septic tanks will gradually build a layer of:
- Solids or ‘sludge’, which settles at the bottom of the septic tank
- ‘Scum’ that floats on top, which typically consists of fats, oils and grease (FOGs)
Therefore, all septic tanks need to be cleaned, emptied or ‘desludged’ by an EPA-accredited Vac Truck business, every few years.
Desludging is one of the most important things you can do to protect and prolong the life of all types of septic systems.
Without regular desludging:
- Your sewer drain could block, which may cause raw sewage to back-up into the house
- Raw sewage may discharge from your Overflow Relief Gully (ORG) in your backyard
- Your system may build high levels of suspended solids, which can block filters, damage pumps, block dispersal (irrigation) fields and clog sand filters
- The quality of the final effluent is significantly reduced
How often do I need to desludge my system?
The frequency of desludging is generally dependent on several factors, including the number of people living in the house. However, the frequency of desludging may increase if excess of the following enters the system:
- Harsh cleaning products such as bleach, chlorine, disinfectants, etc
- Food scraps, fats, oils and grease
- Strong medications such as antibiotics or blood pressure tablets
- Sanitary items
- High levels of grey water
On average, a typical four-bedroom home should have their septic system desludged every three years.
For more information or to obtain a quotation, please contact us on 1800 HARMOR.
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