What is the price of a septic tank?

Thinking about a septic tank for your property, but not sure about the cost? You aren't alone.

Deciding on the correct septic tank to suit your needs can be difficult, as there is a range of factors to consider (most of which affect the price!). That is why we have put together a price information guide to help those in budgeting for their new or upgraded septic tank. If you would like any further information, give Express Wastewater a call at 1300 722 517 and we would be happy to assist further.

Septic tank pricing

It is worth stating from the start that, when it comes to septic tanks, one size does not fit all! No one particular system will fill all your needs, so that is why it is super important to take a look at all the relevant features and speak to an expert.

At Express Wastewater, we pride ourselves on matching the right system with the right person that can save up to and over $15,000.

To help choose the best system for your needs, it is a great option to book a design meeting with an industry professional, so a soil test can be taken. This is used to work out what is the best system for you and your property, including poly or concrete trenches or a treatment plant.

Below is a sample of some of the main styles of systems and why to choose one over the other.

Old-style septic tanks and trenches

Septic tanks and trenches have been around longer than any other treatment option in Australia, with the effluent being broken down in the septic tank to a liquid and then soaking into the ground through a series of trenches. This can be done by gravity or pumped up to the trenches and is generally the cheapest and easiest long-term option to dispose of effluent (especially in a gravity-based system!).

• Why choose this option? You can save money on servicing - $320 per year and power $300 per year - and the cost and hassle of costly breakdowns. Savings are estimated at approximately $1,000 per year.
• Limitations of this option – Reliant on permeable soil, water table, distance to creeks, dams bore etc. and depth of soil over an impermeable barrier.

Approximate cost range

Breakdown of running costs

• Pump out of septic tank every 5-10 years, depending on usage and size of the septic tank. Cost of $200 - $400 ($40 per year).
• Power to run pump (pumped only). Cost of $30 - $40 per year (estimate depending on usage).
• Pump will last on average 5 years - replacement estimated cost is around $600 and installation costs will depend on the type and size of pump used (pumped only). Cost is estimated at $120 per year.

Aerated wastewater treatment plant

The aerated wastewater treatment plant, otherwise known as a Biocycle system or a HSTP, uses an air blower to promote the growth of aerated bacteria that cleans the water within the system. It is then disinfected and will, in time, get to a point where it can be safely irrigated. This method of treating effluent is probably the most versatile option and is generally fairly cost-effective when it comes to installation costs.

• Why choose this option? Versatility, reuse water, generally low install cost.
• Limitations of this option – Needs power, a mechanical part that may break down.

Approximate cost range

• Install cost surface - Indicative - $11,000 to $15,000
• Install cost subsurface - Indicative - $13,000 to $16,000
• Running costs - Gravity - Approximately $1000 per year over a 15 year period‍

Breakdown of running costs

• Servicing $300 - $320 per year (Express Wastewater offer your first year free!).
• Pump out is required every 5-10 years because of the larger quantity of water to be pumped out. This, therefore, means a service agent is required onsite and water fill is also needed - approximately $900.
• Power to run pump and aerator - $300.
• Pump and aerator will last on average 5 years each. Replacement and installation is generally around $600 but will depend on the type and size of the pump used.
• If the system floods and needs pumping, this costs $240 per year.

Sand filter

The sand filter wastewater system comes in a variety of shapes and sizes, suiting a range of homes and workplaces. The basic principle is using bacteria living in the sand to passively clean the water. Depending on the brand of system, the water will either filter through the sand and then soak into the ground like trenches or filter through the sand and then collect into a second tank which can then be irrigated.

• Why choose this option? You will save money on servicing, depending on the system. Savings range between $70 and $320.
• Limitations of this option –  Sand filter options that don’t need servicing are reliant on permeable soil and water table (although there are options around this). The sand filter can also block up through improper use and there is a high install cost.

Approximate cost range

Breakdown of running costs

• Pump out of septic tank every 5-10 years, depending on usage and size of septic tank. Cost of $200 - $400 ($40 per year).
• Power to run pump (pumped only) is around $30 - $40 per year (estimate only as depends on usage).
• Pump will last on average 5 years - replacement estimated cost is around $600 and installation costs will depend on the type and size of pump used (pumped only). Cost is estimated at $120 per year.
• Servicing if required is generally between $170 and $250 per year.

If you would like some further help in relation to septic tanks, give Express Wastewater a call at 1300 722 517 and we would be happy to assist in every way we can.