How Sewage Treatment Plants Work?

How Sewage Treatment Plants Work?

Are you looking for information on sewage treatment plants or are thinking of having a sewage treatment plant installed? Here at CountyClean Group we love to help out as much as possible so have put together this article on everything you need to know!

What is a Sewage Treatment Plant

Well, the clue is in the name but a sewage treatment plant quite simply treats sewage. Working in a similar way to a septic tank but requiring electricity, a sewage treatment plant is more sophisticated and creates an environment that facilitates the growth of bacteria.

The bacteria break down sewage and solids to produce a clean, non-polluting effluent. This effluent can then be discharged (subject to the necessary legal consents required) to a watercourse or soakaway.

Treatment plants can come in a range of sizes to cater for small and large domestic households all the way through to commercial buildings and sites.

How a Sewage Treatment Plant Works

As no sewage treatment plant is exactly the same, we are featuring the WPL Diamond range as an example for this article. As we are experienced sewage treatment plant installers for the WPL Diamond as well as other well-known brands such as; Klargester, Kingspan, Balmoral, Acorn, Allerton and Conder (amongst others upon request), we can carry out the initial install using our groundworks and installations team. Our pump engineers will then commission the plant. We are also able to offer professional advice on project specifications, compliance and guidelines and provide installation, servicing and maintenance.


The WPL Diamond plant is designed to operate automatically with minimal maintenance after it has been commissioned. The WPL Diamond system consists of two treatment chambers in a single tank. The central bio-chamber empties into the bottom of the outer clarifier chamber and located in the centre of the bio-chamber is a circular draft tube.

Air is released at the bottom of the draft tube which causes an upward flow of process liquid. This draws the settled solids from the bottom of the clarifier up through the draft tube where they are discharged at the surface of the bio-chamber.

The draft tube ensures continuous and complete mixing of oxygen with the sewage, allowing for the growth of various aerobic organisms that biologically degrade the wastewater contaminants.

Gravity then causes the aerated solids to settle back to the bottom of the tank where they are drawn back up through the draft tube. As raw sewage enters the aeration chamber it displaces biological solids from the bio-chamber to the clarifier.

This process repeats and the treated effluent will flow slowly up through the clarifier and is then discharged through the dip pipe.

On-going Sewage Treatment Plant Maintenance is Crucial

The WPL Diamond plant requires routine maintenance to ensure continuous and trouble-free operation. At a minimum this should be carried out every 12 months, here at CountyClean Group we can provide this service for customers with our highly skilled and experienced engineers who have all the necessary industry training and certifications. We are also able to carry out routine de-sludging and in the event that a repair needs to be carried out, our fleet of powerful and modern vacuum tankers are on hand to assist.

WPL Diamond pea shingle backfill sewage treatment plant wastewater crop
The discreet WPL Diamond Plant

The WPL Diamond provides customers with a discreet, efficient and cost-effective solution suitable for domestic and commercial properties in all ground conditions where mains drainage is unavailable whilst being environmentally friendly at the same time.

Tank and Sewage Treatment Plant Installation 

If you are considering a sewage treatment plant install, you need to know that the system you are considering suits your needs.

Our fully qualified civil engineering and groundworks teams are able to recommend systems from several manufacturers including WCSEE Group, Klargester Kingspan and Tricel ensuring a perfect fit for your requirements after a thorough site visit.

We will then carry out the full sewage treatment plant install from initial excavation to final commissioning and testing; this ensures that you have peace of mind that you are dealing with one contractor from start to finish whilst ensuring delivery on time and to budget.

How Do I Know if My Treatment Plant is Working Properly?

When you begin to notice problems with your drainage you may have a blockage, build-up of sludge or failing equipment within your sewage treatment plant and will need maintenance, service or repairs to correct the problem.

A foul smell near your property may indicate poor effluent quality from the discharge pipes to the watercourse.

A white algae or sewage fungus is a sure sign there is a maintenance issue and immediate repairs may be necessary. Your sewage waste may also be backing up within the internal and external pipes to and from the house, you may also see damp or boggy ground around your soakaway this could be an indication of a failed outlet.

Finally, we highly recommend avoiding usage of household detergents, bleaches or other chemicals that may upset the biological process.

For more details on how your treatment plant works, please contact us for any questions regarding maintenance, servicing or alternative issues you may have.

If you have any further queries that have not been covered in this article then please do not hesitate to get in contact with us on 01323 741818 or 0800 171 2204. Alternatively, you can leave some details on our contact form or email us at

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