Last updated 14th October 2020
It will usually cost on average £80-£300 to empty a septic tank, but there are a few factors to consider. Take a look at this cost guide to find out exactly how much eptying a septic tank will cost you.
People living in the city or suburban areas tend to take sewer systems for granted, but if you live in a rural location, then you will realise the importance of septic tanks.
If there are no mains sewer system homes will require a septic tank for baths, toilets, and dishwashers to drain into. These tanks need to be emptied around once a year.
A septic tank emptying contractor will be supplying their own specialist equipment to empty the tank and dispose of the contents safely.
They will usually charge around £80-£300 per emptying depending on the size and time it takes to clean. Subject to the size of the tank, this will usually only need to be done once a year.
The size of the septic tank will determine how long it takes to empty, and this may affect the cost.
Some companies charge per 1000 gallon for emptying while others will have a set price for a specific type of tank.
How large the tank is will have been determined by the needs of the property and the amount of effluent being produced.
The larger the property and household, the larger the septic tank will need to be to cope with the amount of waste being deposited.
Round, bottle-shaped or 'onion' tanks and the cylindrical septic tanks both normally have two chambers.
The average cost to empty one of these more modern tanks is £200.
Older masonry or brick-built septic tanks can sometimes have three chambers.
These types of tank cost on average £230 to empty.
In order to empty the septic tank, there should be clear access for the tanker to get close enough for the vacuum hose to reach the sludge at the bottom of the tank.
Septic tanks should be installed within 30 metres of an access point for emptying so this should not be an issue unless the septic tank has been in situ for a long time and before these guidelines came into existence.
The degree of inversion of the pipe from truck to tank can affect the optimum location for the tanker also, but this would need to be discussed on site.
Any obstacles, such as garden furniture or fence panels, may need to be temporarily removed.
A lack of preparation for the arrival of the emptying tanker such as arranging for a parking permit or not advising of narrow or low access may have an adverse effect on how much you pay for the service.
The location of your property within the UK will have an effect on most services that you pay for in the maintenance of your home and emptying a septic tank is no different.
As it is likely that the reason a septic tank is in place is that there are no accessible mains drains in the vicinity a rural location is to be expected.
Some of these properties may be quite remote and incur extra charges.
In some areas, access to the property itself may be difficult or challenging, for example, narrow lanes or weight restrictions on bridges.
|SEPTIC TANK SIZE||AVERAGE COST||DURATION|
|Extra Large||£300||2-3 hours|
In the below table, you'll find the average cost of emptying septic tanks depending on their size and type:
|VOLUME||GLASS-REINFORCED SEPTIC TANK||BRICK OR MASONRY SEPTIC TANK|
As part of a regular maintenance system for your septic tank, you should monitor what is going into it via your drains.
It can be easy to thoughtlessly discard items down the plughole of your sink or into the toilet, especially if you have been used to the convenience of mains drainage.
Owning a property with a septic tank for waste management takes a bit of getting used to in regard to your mindset and habits.
Not only what you dispose of down the drains but also what cleaning products you use.
For a septic tank bleach is a definite no-no as are any anti-bacterial products such as handwash and wipes.
Getting used to checking the detergents and cleaning agents before you buy them takes a while but is definitely worth doing to avoid creating problems with your septic tank.
The environment inside the septic tank depends on the anaerobic bacteria within it to break down the solid waste as much as possible. Therefore, it is important that you do not add anything to the septic tank that would disrupt this balance.
Some of the products you now need to consider buying for your home may be slightly more expensive than what you used to buy but should be viewed as integral to the health of the property's waste management system.
Keeping the drains clear is important so you may consider jet washing to ensure that there is no build of material to stop the flow of waterwater reaching the septic tank.
The average cost of hiring someone to jet wash your drains will be around £250-£300 per day.
CCTV inspection can be used to carry out a detailed examination of the drains if you suspect there is a serious issue.
This can help to prevent a minor issue escalating and developing into a major and potentially expensive problem.
The average cost of a CCTV inspection of drains is between £100-£300 depending on how detailed the survey is.
Individual costs of cleaning a large septic tank - Total Cost: £200
The septic tank emptying cost charged by most waste management companies is based on the volume of the septic tanks, whether that is in gallons or litres.
It can also be based on the kind of septic tank being emptied such as the modern polyethylene or the tradition masonry tanks, and the amount of time and effort required to empty it.
The average cost to empty a septic tank will include the cost of labour.
The extent of the labour cost will be dependent on the size of the tank, the location of the property and the ease of access for the machinery.
The tank operator is responsible for driving the vehicle, operating the machinery, including the vacuum that removes the sludge from the tank and taking it to a sewage treatment facility.
To ensure that the septic tank functions properly and breaks down the waste entering it, a good bacterial balance is essential.
Harsh chemicals such as bleach should never be put into the septic tank as they will destroy the anaerobic bacteria as will anti-bacterial soaps and liquids.
Dishwasher tablets can contain phosphates which are harmful to the beneficial bacteria in the tank so low or no phosphate detergents are best.
Using detergents with low phosphate will help to maintain the good bacterial levels in the tank to aid decomposition of the solid matter and prevent the drainage field being overloaded with suspended solids.
This should mean that the environment inside the septic tank is optimum for breaking down the solid matter, and this should mean that the sludge will not build up quickly.
In turn, this means that emptying will need to be done less often and will reduce the maintenance cost of the septic tank.
The length of time taken to empty a septic tank will be determined by a number of things; the volume of the tank, i.e. the amount of waste it holds, the access to the tank from the highway and also the experience of the tank operator.
On average it should take no more than a couple of hours to empty an average-sized septic tank.
A large tank will take longer to empty than a smaller one due to the amount of waste involved, but some smaller tanks may have become blocked or overfilled and therefore take some time to empty.
An experienced tank operator will have knowledge of different types of tank and will be confident in driving and operating the machinery on the tanker.
This should mean that the operation is carried out quickly and efficiently. If the operator is new or relatively inexperienced, then the process may be a little slower.
They may not be as familiar with the equipment or as confident in manoeuvring the vehicle as more veteran operators.
As long as the tank emptying is carried out properly and you are not expected to pay for a slightly longer operation, then it should not present a problem.
Good access for the tanker is important to avoid delays and giving clear instruction to the waste management company will hopefully avoid an unsuitable vehicle being despatched to empty your tank only to find it is too big or wide for the road or too heavy for a weight-restricted bridge.
In order to get the vacuum tanker close enough to the septic tank, proper access will be necessary.
By being prepared in advance and removing any obstacles, you can ensure that there is no time lost in trying to manoeuvre the vehicle or causing a delay while obstructions are removed.
No preparation for access to the site of the tank, meaning the contractor is left to wait while the householder clears a path to the septic tank site may mean you pay more.
Some waste removal contractors may not wait if they have other clients booked, and it may be necessary to re-book.
This could cost a lot as the contractor may charge for a failed visit, and you then need to pay for a second booking.
If it comes to light that there is an issue with the tank itself perhaps that it has not been emptied in a very long time or there is material in the tank that should not be there, then the emptying process may take longer than normal.
Items such as sanitary products or cat litter are often flushed down the drains and cause serious blockages.
These items will not biodegrade and will fill up the septic tank much quicker, resulting in more frequent emptying being needed.
Here are some factors that can affect the overall cost of emptying a septic tanks:
In terms of the cost to empty a septic tank, the size of your tank has a major effect as you would imagine. The bigger the septic tank, the more work to empty it out and flush the solids.
But when choosing a tank, you need to remember that it is not serving just the toilet and bathroom water, but also water from washing machines, sinks and dishwashers too - so you need a tank with adequate capacity.
Smaller septic tanks are cheaper to install as they can often be above ground so no excavation costs.
The tank itself is cheaper to buy, but smaller tanks will also require emptying more often, which can be expensive over the tank's lifetime.
Larger tanks cost more to buy and install as they are usually underground but are cheaper over the long term.
The other benefit of a large septic tank is that a soak-away can be used for some of the waste-water to be filtered out, so the tank can be emptied even less often.
As long as septic tanks are emptied regularly and have been installed properly in the first place, they are largely problem-free.
The size of the tank will have an impact on the cost of emptying it with the larger tanks costing between £250-£300.
The two most prevalent types of septic tank in the UK are cylindrical and round or 'onion' shaped.
They are constructed from glass-reinforced plastic or polyethylene or in the case of older septic tanks from masonry or brick.
The older types of septic tank have either two or three chambers which facilitate the filtering process of the waste and are usually rectangular in shape.
All septic tanks, new and old need the addition of a drainage field for the wastewater to percolate through to the soil.
The location of the property in the UK will have an effect on the septic tank emptying cost, although few properties in London will require this service due to the prevalence of mains drainage.
However, in the south-east of the country, there are still rural properties which have septic tanks, and the cost to empty septic tanks in this part of the UK may be higher due to the higher cost of living.
Many properties which rely on septic tanks for household waste management are located in rural areas.
This can be a challenge for access in some instances with narrow lanes, remote locations, and off-road sites.
As a general rule, a septic tank should be emptied every twelve months, but this does depend on the size of the tank and the number of people living in a property.
For more people in a small to medium household, then annual emptying is advisable whereas fewer people in a large property may mean this can be done every 2 years.
There will be signs if a septic tank is full and struggling to cope with the waste being deposited.
Toilets will be slower to flush, drains may take longer to empty, or you may notice a bad smell coming from the area of the septic tank or drainage field.
All of these signs point to a waste system that is struggling, and this needs to be addressed quickly to avoid or mitigate damage to the tank or the drainage field.
If left unchecked then the damage could be irreparable, and the drainage field could become unusable, and if you have no other ground to locate a new drainage field too, this will present you with a significant problem to fix.
Most contractors will need to drive a tanker onto your property so they will need unobstructed access between the septic tank and the parking area.
The de-sludging or emptying service offered to customers with septic tanks usually includes the removal and treatment of around 1000 gallons of sludge.
As part of the emptying process, the tank is also normally 'backwashed' to remove any solid waste.
This emptying service can be done as a one-off or more often as part of a regular maintenance contract.
Emptying a septic tank is not something that can be done as a DIY job. Due to the nature of the work and the waste involved, it is strictly regulated and must conform to the law on pollution and water safety.
Only a licenced waste disposal contractor is permitted to empty a septic tank, and it is illegal to allow anyone else to do this. The waste has to be removed to a waste treatment plant and properly sterilised and discharged.
Make sure access to the site is adequate and without obstruction. Informing the waste contractor of any restrictions on access is necessary to avoid being charged for a failed visit.
If there are narrow country lanes or difficult terrain to be negotiated, it is important to let them know in advance so that the appropriate vehicle can be delegated to the job.
Some companies have mini tankers for tight spaces, and others have towable tankers that can be pulled by a 4x4 vehicle for tricky ground.
However if you don't let them know in advance, your waste contractor could turn up in a large, multi-ton truck and if it cannot gain entry to the site, then you may be charged for a failed visit and pay for a different vehicle to attend your property.
Older septic tanks were normally brick-built rectangular receptacles with two or three chambers to filter the waste.
These days septic tanks are made from glass reinforced plastic or polyethylene and can be either rectangular, cylindrical, or round 'onion' shaped.
Cylindrical tanks are designed for shallow installation, which means that it is not necessary to excavate a large hole to insert them.
They normally consist of two chambers with an inspection/access hatch above ground for each chamber.
Cost of cylindrical septic tanks: the average cost of a 2800 litre cylindrical septic tank is £950.
Round septic tanks are sometimes referred to as 'onion' tanks due to their bulbous shape and extended neck to the access hatch.
The flow inside this type of tank is upward as opposed to lateral in a cylindrical tank.
Cost of round septic tanks: the average cost of a 2800 litre round septic tank is approximately £600.
Glass-reinforced plastic is a light but strong material which has largely replaced concrete in septic tank construction.
It is watertight and chemically resistant, making it ideal for this purpose.
Cost of glass-reinforced plastic septic tanks: the average cost of a 3800-litre glass-reinforced plastic septic tank is £1100.
Concrete is a very versatile and widely used material in all types of construction and septic tanks are no exception and were among some of the very first septic tanks installed in the UK.
Although it may be possible to buy a bespoke pre-cast concrete septic tank, the most common concrete domestic sewage management systems are now waste treatment plants. These are more environmentally friendly as they produce much cleaner waste.
This is reflected in the price although they do have a longer service life than an average septic tank.
The average cost of a pre-cast concrete treatment plant is around £5000.
Septic tanks use an inlet pipe that comes from the property into the tank and an outlet pipe that runs into a drainage field.
A drainage field is a network of perforated or slotted pipes which allow the wastewater to percolate slowly into the ground without causing pollution.
This process further filters the wastewater removing more bacteria and solid elements from it.
The septic tank separates out the waste into 'scum', 'separated waste-water' and 'sludge'.
It is the separated wastewater which runs into the soak-away system; the more solid yucky stuff stays in the tank, which is why septic tanks need to be emptied out on a regular basis.
If you do not empty your septic tank regularly, then toilets will start taking longer to flush, and you may even get smelly waste backing up to your home.
The wrong kind of waste can then get into the soak-away system and begin pooling above ground; this creates an awful smell and can even pollute local water sources.
At least once a year you should have your septic tank emptied if only to maintain the system in good working order.
Large tanks may not fill up, but it is good practice to empty them regularly to ensure that the tank is working effectively.
A small, crowded property with a septic tank will put pressure on the system, and the tank may need to be emptied on a more frequent basis, e.g. every six months.
This can happen if you have put an extension on a property with a septic tank without replacing the tank to allow for the added usage.
The size of the septic tank will dictate how much waste it can hold, but the rate at which it fills will be determined by the number of people in the household.
Obviously, the more people in the house, the more waste will be produced; therefore, the septic tank will need to be emptied more often.
An allowance of 180 litres per person per day is used to calculate the size of the septic tank that a property would require so this represents the capacity of the tank in relation to how frequently it needs to be emptied based on the occupancy of the property.
The responsibility for a septic tank on your property and the waste it contains is explained in the General Binding Rules. Changes from January 1st, 2020 relate to the disposal of waste into a watercourse.
As of that date, any septic tank that discharges into a ditch, stream or river will need to be replaced with a waste treatment system or the waste must be diverted to a drainage field.
A property that has a septic tank discharging into a watercourse cannot be sold without the upgrade to a waste treatment system or the addition of a drainage field. This is the sole responsibility of the owner and at their cost.
The Environment Agency is responsible for the regulation of septic tanks and can impose fines if they are not compliant and pose a potential pollution threat.
The fine for failing to comply with these regulations and potentially polluting a water source can be up to £100,000.
The size of the septic tank servicing your property and the number of people living there will determine how often the tank needs to be emptied.
However, it will need to be emptied or 'de-sludged' at some point, and you will need to hire a professional waste disposal specialist to carry this out. It is not possible to do it yourself or pay a non-licensed person to do it for you as this would be breaking the law.
The average cost to hire a waste management company to empty your septic tank is approximately £200.
Regional variations may apply, and there are slight differences between prices for emptying a glass-reinforced plastic septic tank and a brick or masonry built one.
Only registered waste disposal contractors are licensed to carry out the emptying of a septic tank.
The waste must be taken to a sewage treatment works where it is treated and sterilised before being discharged.
Ensure that any company that you hire to empty your septic tank holds the correct licence to do so.
It is a good idea to use a company that has been established for some time so that you know that they are reputable and will have experienced staff.
All waste carriers should have the appropriate insurance as it is a high-risk industry with the potential for injury and pollution.
You should ask any waste management contractor you are hiring to empty your septic tank for proof of their liability cover.
A waste management company will need an environmental permit to carry out their activities; you can ask for evidence if you are unsure.
This link is a register of licenced waste carriers. Only those contractors who have the correct licencing will be on this register, so it is possible to either find a suitable company or to check that the company you are using is on the register.