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How does Underground Drainage work?

When it comes to understanding how your Underground Drainage works, why not let Total Pipeline Systems talk you through the basics?

What is Underground Drainage?

An Underground Drainage system is used to discharge surface, foul and grey water. Surface water refers to rainwater and stormwater where foul water is the water discharged from toilets and grey water is the waste from baths, sinks, washing machines and dishwashers.

The most common Underground Drainage Pipes that we supply are the 110mm pipes and 160mm pipes, however, we can provide you with all that you possibly need to enhance the functionality of your Underground Drainage system.

Regardless of whether you’re looking for products for your domestic system or your commercial system, you can count on Total Pipes to stock it!

How does the Drainage System work?

Underground Drainage is simple when you know how it all works. Wastewater is discharged from the sanitary appliances that you have in your home, so anything from the toilet and bath, where it will eventually transfer through large vertical pipes. It’s through these pipes that the wastewater will reach the main Underground Drainage System.

Depending on the age of your property, the number of Underground Drainage Pipes will vary. Modern homes tend to have one pipe which is called a Soil Stack, whilst older homes have separate pipes to separate soil and wastewater.

Where does the water go?

The water that is discharged can go in one of two directions, it either:

  1. Runs straight into the main sewer, cesspit or septic tank


  1. Flows to the main drainage stack which leads directly into the underground drain or trapped gully

If the latter, a metal or plastic grid or gully is fitted to the drain to prevent the build-up of debris. The grid essentially eliminates the chances of the Underground Drainage Pipes becoming blocked with leaves and other debris.

What about Rainwater Drainage?

A heavy downpour is likely to overwhelm the system- hence why water from guttering is drained separately. Downpipes are often used to discharge rainwater over a grid or open gully that is connected to an underground drain pipe.

After this, water can either run into a storm drain that’s installed beneath the road or it can be piped into a soakaway in your garden to percolate back into the soil.

Who is held responsible for the Underground Drainage system?

Put simply, you are liable for your Underground Drainage. As the homeowner, Underground Drainage Pipes are your responsibility, until they reach the main sewer, therefore, you will need to fix any blockages or damages that occur, at your own expense!

Modifications of the system come under the stringent Building Regulations which are enforced by the local council and not the water company. If you’re thinking of modifying your Underground Drainage System, you need to make sure that they meet the Building Regulations, so be sure to discuss your requirements in detail with the building control officer.

How to cut and join Underground Drainage Pipes?

The Underground Drainage Pipes are easy to cut with a fine-toothed saw. The end of the pipes are chamfered and you need to carefully remove dirt and grit. When joining the pipes, make sure that they are square to the fitting and pushed fully into the socket, in doing so, withdraw 10mm of the pipe to give for expansion and ground movement.

There are strict rules surrounding the installation of new Underground Drainage Pipes and the modification of systems, hence why it’s always better to check with the Building Control Department to ensure that your plans are feasible and legal!

Choosing Supplies from Total Pipes

Here at Total Pipes, we have an extensive range of drain pipes available, including the popular 110mm drainage pipes and the 160mm drainage pipes. Although we specialise in supplying drainage pipes, we also provide a wide range of pipe fittings and drainage gullies and gully traps, essentially making us your one-stop shop for your Underground Drainage supplies!

Our UPVC pipes and pipe fittings for Underground Drainage systems are made to meet EN1401 standards and are suitable for various land and surface water drainage applications.

The team at Total Pipes take pride in the products that we deliver, so if you cannot find exactly what you’re looking for, don’t hesitate to contact our sales team and discuss your specific requirements in more detail, we will be more than willing to provide you with any advice or support that you require.

Call us on 01282 222077 to find out more today!