How to build a soakaway

Suggested meta description: Want to know more about soakaways? Discover how to build a soakaway and the benefits of doing so with the expert team at OMDI.

What is a soakaway?

Soakaways are a type of groundwater infiltration system optimised to meet a property’s long-term drainage needs.

Dealing with standing surface water, soakaways are an ideal solution for those who want a safe and effective method of excess water disposal.

In this context, it is worth exploring the idea of how to build a soakaway in the UK and identify the benefits of installing this type of surface water drainage system.

Site assessment and planning

Soakaways are located in areas near pavements and gardens and they permit the disposal of rainwater and liquid sewage waste from a property.

On a technical level, soakaways are a hole dug into the ground and filled with coarse stone that permits surface water to percolate back into nearby earth.

When deciding how to build a soakaway, many factors need to be assessed such as the potential size of the soakaway, its distance from nearby buildings, and the quality of the ground to see whether it is appropriate for the installation of a soakaway.

A soakaway system must be designed to be a good distance away from anything that could hinder its function. For example, 34ft away from ditches and 164ft away from water abstraction points.

Furthermore, when exploring how to build a soakaway in the UK, it’s important to consider whether it is for a residential property, how many bedrooms it has, and the porosity of the soil, which informs the size of the drainage field that should be installed.

Choosing the construction method

Prior to building a soakaway, identifying the soil type is also necessary.

Not only that, if you are building a soakaway in the UK, the   dictate the appropriate kind of drainage system for a particular property.

This can be achieved by conducting a percolation test which is carried out by an experienced drainage specialist.

This is one of three mandatory tests for gauging relevant surface water drainage options, and the results indicate whether the soil is permeable and its capacity to regulate the flow of surface water.

A percolation test entails digging 300mm into the ground, underneath the potential invert level of the distribution pipe and left overnight.

The hole is then filled again and monitored to determine how long a specified amount of water takes to seep away.

By conducting this process at least three times in each of the trial holes, an average time is gathered. This can help us gauge the appropriate area size of the soakaway.

Step-by-step soakaway construction process

To build a soakaway, it is important to contact a drainage specialist to determine the precise needs of your property.

This team of experts can conduct a percolation test which should allow you to get the ball rolling when you want build a soakaway in the UK.

When the storage volume is gauged for your property, as well as the appropriate location and the depth of the soakaway, a range of items will need to be ordered including the soakaway crates, geo-textile membrane and slit-trap/pre-filter.

The next step is digging the hole for the soakaway and pipes.

During this stage, enough depth will need to be guaranteed to accommodate a base layer of rock/rubble as well as the soakaway crates and pipes.

An experienced installer such as OMDI will then need to lay the base layer evenly in the bottom of the drainage system hole. It is there the geo-textile membrane will need to be inserted. Then, the soakaway crates will need to be placed into the hole and secured with cable ties or something else that binds them together.

Next, the flow pipe will need to be linked to the soakaway crates guaranteeing the membrane is secured around all parts of the drainage system.

You may also be advised to include a slit trap / pre-filter above the soakaway to ensure longevity and efficiency of your drainage system.

Post-construction inspection and maintenance

The inspection and maintenance of a soakaway is equally as important as learning how to build a soakaway.

If you have arranged for a new drainage system to be installed, it is vital the relevant building regulations for soakaways are adhered to. This will pave the way for the system to be properly maintained post installation.

With our expertise in the water drainage industry, installing soakaways for domestic and commercial properties, OMDI can conduct all the relevant and necessary tests and advise the most effective and suitable system design for your property.

Be sure to contact us today to discuss your requirements with one of our experts.

You can either fill out our contact form or give us a call on 01977 800 418.