Did you know, the UK collects over 11 billion litres of wastewater every single day? That includes water from the baths, sinks, toilets and washing machines in your home, industrial wastewater and rainwater run-off from roads. It’s a lot to deal with on a daily basis. But without the correct treatment, such wastewater (or sewage) can have a significant adverse effect on both the water environment and public health – which is why it’s so important to get it right.
Adhering to the Urban Waste Water Treatment Directive of 1991, the UK has an incredibly stringent water treatment process. This is designed to remove all organic substances naturally – ensuring that water is clean and safe enough to be returned to our streams and rivers.
5 stages of wastewater treatment
The first step is to ensure wastewater successfully reaches the UK’s sewage works. No matter where it comes from, it has to follow the same route. The sewage is guided through drains and into the sewers – where it is then carried, via underground pipes, to the nearest sewage treatment plant.
Sewage pumping stations, such as those available at JT Pumps, often have a crucial role to play at this stage. For example, if a room falls below the main sewer line (e.g. a basement bathroom or utility room) or connection to the main sewer line is difficult, a sewage pumping station may be required to pump the sewage – against the force of gravity – until it gets to where it needs to be.
2. Preliminary screening
Lots of things get into the sewerage system that shouldn’t be there. For example, it’s not uncommon to find nappies, sanitary pads, incontinence pads, condoms, cleaning and make-up wipes, plastic bags and more – all of which must be removed before sewage treatment can begin. Debris and gravel that has washed in from the roads are also taken out at this stage.
3. Primary settlement
The next step in the sewage treatment process is to separate any suspended solids. This is done by pumping the wastewater into large sedimentation tanks. Particles of solid waste are heavy, and as such, sink to the bottom of the tank. Here they form a layer of sludge that can then be removed.
4. Secondary sewage treatment
Now that all visible debris has been extracted, it’s time to tackle the invisible dirt.
This is done via a two-stage biological treatment. Firstly, wastewater is held in large tanks and air is pumped in to encourage bacterial growth. This is called the ‘activated sludge process’. Subsequently, the water is passed over specialist filter beds. These beds contain billions of ‘waste-eating’ bacteria, which essentially, digest the organic matter and break down waste into harmless substances.
5. Tertiary treatment
This is the final step of the wastewater treatment process. At this point, the water is already very clean – it’s just the last few waste particles that need to be removed before it can be discharged.
The exact tertiary sewage treatment required will depend on the nature and sensitivity of the receiving water. For example, disinfection is typically needed for bathing or shellfish waters. Whilst phosphorous and nitrates (i.e. nutrients present in the sewage) will also need to be removed to protect waters that suffer from eutrophication (i.e. excessive richness of nutrients).
Either way, the process is the same. The wastewater is simply passed through a special tank – called a humus tank – or a reed bed, before it can finally be released into the chosen water body.
Set your wastewater on the right track
If you would like further information on the water treatment process – or need advice on how to improve wastewater management in your home – please feel free to get in touch.
Here at JT Pumps, we have expert knowledge of the UK sewerage system and we’re always happy to answer your questions. What’s more, we have a comprehensive range of sewage pumping stations available to buy – all of which are designed to pump wastewater (horizontally and/or uphill) and ensure it reaches the main sewer line, when gravity cannot be relied upon to do the job.