Sewage treatment plants are a regular sight for households and businesses across the UK.
They serve a vital purpose for properties not connected to the mains sewage, helping to remove contaminants from sewage, producing clean water that is safe to discharge into the local environment.
In this piece we will explore how they work and various functions depending on size, plus the differentiation compared to septic tanks.
The Sewage Treatment Plant process explained
Wastewater is flushed out of the building, where it will flow into the primary chamber of the sewage treatment plant.
Gravity will act to separate the solids from the liquids.
The solids will settle at the bottom of the tank, and are removed.
The liquid will flow into a secondary chamber.
In this secondary chamber, bacteria will begin to break down the sewage. This takes place under aerated conditions.
Once the sewage has broken down, the treated wastewater will flow into a third and final chamber where the bacteria will settle towards the bottom and be removed, leaving the clean water to flow out.
You can learn more about the specifics of the process by reading Water UK’s explanation.
Differences between Domestic, Commercial and Industrial sized Treatment Plants
There are multiple stages to a sewage treatment plant that converts raw sewage into treated water safe enough for drinking and washing in.
The main differences between treatment plants is whether the effluent is treated to be safe for discharge into the water network, or treated through a chlorine contact tank and a dual media filter that will ensure the water is safe enough for human consumption.
Many different manufacturing suppliers develop these advanced waste management systems, and you can read about four of the very best by clicking here.
What happens to the Effluent from a Sewage Treatment Plant?
Effluent is the name given to the treated water that flows out of a sewage treatment plant. There are two options for what happens to this effluent.
- Either rerouted back into the mains sewer system
- Discharged safely into the local environment
If the latter is chosen, it is especially important to work closely with a professional installer who will ensure that the discharge is not to the detriment of the nearby soil or water network.
If the treated water is returned to the mains sewer network, it will end up being treated to a specified quality safe to discharge as drinking and bath water.
What are the benefits of sewage treatment plants?
Sewage treatment plants help to prevent water pollution from sewage for properties that are not connected to the mains sewage. They can be installed in challenging or compact sites, ideal for remote properties that might be limited on space.
Sewage treatment plants are considered more environmentally friendly than septic tanks, as they treat wastewater more thoroughly and efficiently.
They also do not release ammonia as septic tanks do, which is harmful to the local wildlife and environment. Sewage treatment plants can also discharge treated wastewater into local watercourses such as rivers and streams, while septic tanks cannot.
Sewage contains bacteria that break down with oxygen in the water, which can limit the amount of oxygen available for the fish and aquatic life, leading to potentially fatal consequences as a result.
Another key benefit of a sewage treatment plant over a septic tank is the significantly reduced size requirements for the soakaway drainage field.
Sewage Treatment Plants vs Septic Tanks
Whilst the two serve a roughly similar process of collecting wastewater from properties not connected to the mains, there are a number of differences between sewage treatment plants and septic tanks.
Septic tanks produce a waste product that is a pollutant, and must be dispersed to a soak-away where a natural aerobic process will take place in the soil. Treatment plants produce a clean, non-polluting effluent that is sent to a watercourse.
Another major difference is that septic tanks are more straightforward in their operation, they do not require electricity or regular servicing. You can read about how septic tanks work, here.
A treatment plant often requires electricity to operate, as well as regular servicing.
Both a septic tank and treatment plant will require regular emptying to remain fully operational – read our recommended guidance on septic tank emptying.
Servicing of a Sewage Treatment Plant
Similar to a car, a sewage treatment plant will require regular servicing to remain fully operational.
Without regular servicing and maintenance, it runs the risk of failing to properly process the wastewater, which could become a major environmental issue. Similarly, regular emptying of your treatment plant will ensure it does not overflow or become clogged up. The last thing you would want is the wastewater to start coming back to its original source; your bathroom or kitchen!
Here at Peachy Services, we are experts in the installation, maintenance and emptying of all types of domestic and commercial waste disposal systems. We’re based in Crawley, West Sussex and cover most of the South of England. If you have any questions or need anything to do with sewage treatment plants, septic tanks or cesspits, let us know how we can help.
