The line in Finding Nemo, ‘All drains lead to the ocean,’ is quite a famous quote, but is it accurate?

To answer the question, “What happens after you flush?” we need to look at the different types of waste that leave our properties through the drains, what treatment that waste goes through, and where it ends up.

‘Wastewater’ means any water that leaves your house via your drains. This could be from washing your clothes, flushing your loo, or draining the sink. Many people think that all sewage is human excrement, but actually all wastewater is referred to as sewage.

Where Does Wastewater Go?

Whether it comes from a domestic or commercial property, all wastewater travels the same route through the sewer pipes.

First, it’s flushed into the sewer system. The pipes from your home or business connect to a larger pipe on the street, which then join up with even bigger pipes. Some of these can be enormous, even as big as buses!

These large sewer pipes are the ones which transport the wastewater from your house all the way to the treatment plant.

Why Does Sewage Need to be Treated?

In the distant past, sewage was thrown onto the streets. This obviously caused some pretty serious health issues, and pollution levels were out of control.

The modern sewer network means that sewage today is sent to a treatment plant. Nemo is correct; all drains really do lead to the ocean, but they don’t lead straight there. Before reaching the sea, the sewage must be thoroughly treated to avoid posing a risk to both human and aquatic life.

How is Sewage Treated?

The wastewater that leaves your home or business passes through a variety of treatment methods before it enters the rivers and oceans. The stages between flushing your loo and the water entering the sea are outlined below.

  • First, You Flush the Toilet

All the sewage flows into the sewer pipes under your house, which joins larger pipes before making its way to the nearest treatment plant.

  • The Pre-Treatment Stage

This is essentially a big sieve. Any items that shouldn’t have been flushed down the drain in the first place will be removed here. That’s wet wipes, sanitary items and other debris.

  • Primary Stage of Sewage Treatment

The sewage then passes through a series of filters, separating the liquid and the sludge, so that solid leftovers can be taken to landfill.

  • The Second Stage of Sewage Treatment

Next, bad smells and bacteria are removed from the water through a process called aeration. This is where oxygen helps to break down the bacteria and organic matter.

  • The Final Treatment Stage

Further aeration takes place, followed by reducing nitrogen and phosphorus. Different treatment plants use different methods. Some also use a UV light and chlorination treatment to remove any bacteria that remains. This makes the sewage clean and ready for release back into the rivers and seas. It is only released once it has met the Environment Agency’s quality standards regulations.

Eventually, this water will evaporate to form clouds, fall back down as rain and potentially find its way back into the waterworks. Then it will be treated again, before coming out of your kitchen tap and starting the process all over again!

If you’re having any trouble with your drains and your wastewater is not leaving your home as it should, get in touch with us and we’ll pay you a visit.