Does Adding Substances to Your Sewage System Really Work?

Poured Down Loo


You may have heard of these additives that suppliers claim provide an effective alternative to getting your septic tank emptied regularly. But what a lot of you may be wondering is whether they really work, or whether they actually are a sustainable alternative to getting your septic tank emptied annually.


The additives in question are said to provide biological treatment for digesting organic waste. The producers behind the substances claim that they are made up of completely organic product and will not counteract the necessary bacteria already in your septic tank. They are said to reduce the need for repeated tank clear outs and soak-away repairs or replacements, naturally restore and maintain sewage systems, unclog drainage systems and remove odours.

To utilise them, it would require you to pour the liquid down your toilet at regular intervals. These intervals must be met otherwise this will lessen their effectiveness.


Researchers have stated that, for septic tanks, there’s really no need to add bacteria.  This is because, in the UK, the moderate climate means that the rate of anaerobic digestion is very slow, meaning that sewage systems, such as septic tanks, function more as a sedimentation tank than a bio-digester. What this means is that physical processes are much more important than biological ones, so there is no need to try to optimise the biological processes with additives. A healthy sewage system should already have all the micro-organisms it needs, and therefore you may be doing more harm than good by adding these substances to your sewage system in its long-term life-cycle.

Scientists advise that maintaining a healthy sewage system can be achieved by monitoring water usage and ensuring that it is emptied regularly in accordance with the rate at which it is filling up.


The Environment Agency states that you should have your septic tank or sewage treatment plant emptied every twelve months regardless of whether it is full or not. Therefore, with the cost of these additives at around £30-£50 a year, you will still need to arrange for annual sewage clearances to be made at an additional charge.

Finally, for the additives to take effect, it requires monthly maintenance work on your part, remembering to add them in order to ensure optimal effectiveness. Is it worth the hassle?

What do you think? Do additives really work? Leave your comments below.

Keep Your Sewage System in Tip-top Condition

Septic Tank (ThoughtBubble)


Ultimately, maintaining your sewage system will save you money in the long run. In accordance with manufacturers’ recommendations, regular maintenance and repair work should be undertaken and may cost roughly between £200 and £300 annually, whereas replacing a damaged system can incur a one off cost up to £14,000.


Look – check for pooling of wastewater or muddy ground surrounding your sewage system. Also, check for your sink and toilet backing up.

Smell – check for odours of sewage or a ‘rotten egg’ smell around your system or even in your basement or cellar.


Be water conscious – the volume of water your tank can hold will determine how often you need to empty it. If your tank holds less than 1000 gallons it will fill up faster and require servicing more regularly, therefore monitoring your water usage can greatly improve your systems working capacity.

Protect your tank – try not to put anything heavy on the ground over or around your tank or soak-away such as a shed, parked car, above ground pool or hot tub. This can compromise the effectiveness of the soak-away.

Only flush biodegradable products – ideally only toilet paper and waste water should be flushed down your toilet; try not to flush anything non-biodegradable or chemicals. Flushing solids down your toilet can clog the tank and soak-away and chemicals can kill bacteria that help break down solids.

Finally… Consult the Experts! – SepticTanksAndCesspits offer a comprehensive maintenance & repair service, providing inspections and pump repairs in order to ensure your sewage system is running smoothly.

New Plans to Deregulate Domestic Sewage Systems

Blog Septic Tank

Over the last few months the Department for Environment, Food and Rural Affairs (DEFRA) have been consulting on making changes to the regulations on domestic sewage systems in England. DEFRA has set out a clear objective of extending its risk-based approach to permitting. It represents a new focus on environmental permitting that will only be required in or near designated sensitive areas such as national and local nature reserves or sites of protected species and habitats.

What Does This Mean?

It means that the regulations surrounding discharges from domestic sewage systems will no longer be in place. However, although discharges such as these will not require permits, they would still be subject to general binding rules specifying that the system must be properly installed and maintained.  [MORE ON OUR MAINTENANCE & REPAIR SERVICE]

The term ‘domestic sewage systems’ is used loosely and also refers to schools, restaurants, takeaways, nursing homes and holiday parks that are off-mains drainage. It does not, however, include industrial discharges, estates or larger commercial businesses.

DEFRA estimates that these changes will affect around 400,000 sites.

How will it Affect You?

If you or your business has a septic tank or small sewage treatment plant that only produces small volumes of discharge, whilst you are responsible for ensuring the system continues to undergo regular maintenance checks, you will no longer be obliged to keep maintenance records or notify the Environment Agency if your system stops working.

The changes will officially take effect as of January 2015.

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)

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