Septic Tank and Cesspit Emptying Costs

The true cost of maintaining your sewage system.

You can find a lot of information surrounding the cost of maintaining and emptying septic tanks or cesspits; especially on the internet. If you are thinking of buying or moving to a property which is off-mains drainage, you will naturally be keen to understand the types of sewage systems out there and the costs involved in emptying and maintaining them. In this article, we will hopefully dispel some of the myths and help set your mind at ease.

We’ll start with an overview of the most common sewage systems in use.

In the past, there was really only ever one option for off-mains sewerage – a cesspit. A cesspit is simply a sealed holding tank for household wastewater and requires emptying at regular intervals, dependent upon the size of the tank and the number of people living at the property. A cesspit or cesspool is not designed to treat the wastewater and sewage in any way – it simply stores the waste.

The next option is a septic tank. A septic tank normally comprises of two chambers.

As sewage and wastewater enter the first chamber, any solids are ‘encouraged’ to settle at the bottom where they will be decomposed by the septic bacteria through anaerobic digestion. A crust will also form on the surface; ensuring the perfect environment for the bacteria to survive. Meanwhile, the liquors will flow into the secondary chamber, where smaller suspended particles are again encouraged to settle before the liquors finally exit the tank through to the soak away system and into the surrounding environment where any residual impurities are trapped and eliminated in the soil.

Of course, any discharge into the local environment is subject to a ‘consent to discharge’ issued by the Environment Agency. Septic Tanks do not require full emptying, however, they do need to be regularly ‘de-sludged’. This process involves removing the solids or sludge from the system but ensuring that enough bacteria-laden water remains for the system to continue to operate effectively.

Finally, we have the Sewage Treatment Plant. The sewage treatment plant process is similar to the way that a septic tank works but mechanical components help break down liquid waste to produce a much cleaner, more environmentally friendly effluent.

Wastewater and sewage are fed into the primary settlement tank where solids and liquids separate and the liquor flows into the ‘biozone’ chamber. In this chamber, a pump aerates the waste and encourages good bacteria to digest the organic matter; breaking it down and purifying it.

As it leaves the final chamber, (known as the humus chamber), the effluent is typically 95% clean and ready for discharge into local watercourses, ditches or land drainage systems; again, subject to consent from the Environment Agency.

As well as a regular emptying cycle, (normally at least once a year), a sewage treatment plant needs to regularly serviced and maintained, in accordance with the manufacturer’s recommendations, in order to keep the mechanical components in perfect working order.

Approximate Costs

As well as the size or volume of your system and the number of occupants in your household, clearance costs will vary from region to region and is often dependent upon the disposal rates charged by your local water authority. The costs below are for guide purposes only

Cesspit: (widely considered to be the most expensive sewage system to maintain)

Emptying Frequency:                      8 – 10 times per year, (often more frequently).

Average cost per empty:

1000 Gallons / 4500 Litres:            £110 – £130

2000 Gallons / 9000 Litres:            £170 – £200

3000 Gallons / 13500 Litres:          £220 – £260

4000 Gallons / 18000 Litres:          £280 – £320

Septic Tank: (generally considered the cheapest sewage system to maintain)

De-sludging Frequency:                 1 – 2 times per year.

Average cost per clearance:

1000 Gallons / 4500 Litres:            £110 – £130

2000 Gallons / 9000 Litres:            £170 – £200

3000 Gallons / 13500 Litres:          £220 – £260

4000 Gallons / 18000 Litres:          £280 – £320

Sewage Treatment Plant:

Maintenance frequency:              1 – 2 times per year.

Maintenance cost per visit:         £120 – £200

De-sludging Frequency:               1-2 times per year.

Average cost per clearance:

1000 Gallons / 4500 Litres:            £110 – £130

2000 Gallons / 9000 Litres:            £170 – £200

3000 Gallons / 13500 Litres:          £220 – £260

4000 Gallons / 18000 Litres:          £280 – £320

Electricity per year, (to run):          £150 – £250 (depends upon efficiency of STP and electricity rates)

Hello world!

Hello and welcome to the Septic Tanks and Cesspits blog!

Whether you’re new to the world of off-mains drainage and have recently moved into a property with a cesspit, or if you have lived with the joys of pump stations and sewage treatment plants for many years, our new online sewage clearance booking site is the place for you.

Simply enter your postcode to get an instant quote and, if the price is right, book one of our tankers to come and empty your sewage system.

You will find our prices are extremely competitive and our service is second to none.

Thanks for reading and we hope to be of service very soon.


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