Buyers guide for soakaways

What is a Soakaway?

Due to the increase of heavy rainfall throughout the UK (, it has become extremely common for surface water to evolve in certain areas.

If an increased level of pooling and unwanted surface water is noticed, or water building up around exterior walls, it is suggested that investing in a soakaway can resolve this.

A soakaway is a type of underground drainage system that aims to manage surface water on a property. It allows it to seep into the ground rather than discharge it into a watercourse or sewer. The modified plastic crates (Attenuation Crates) are fitted into holes in the ground that that you must dig out.

Attenuation functions by gathering extra rainwater and enabling it to seep back into the ground when your home’s main drainage system is overworked. The system is easy to install and over the life span need very little maintenance. They are one of the most environmentally beneficial methods for dealing with excess surface water. This is because of how simple they are to use and how they encourage healthy garden turf.

More detail surrounding a Soakaway unit…

A soakaway is a sizable hole excavated in the grounds of a property to catch and hold rainwater or surface water before releasing it gradually into the surrounding soil. It is generally built five to ten metres away from a building. It uses a permeable membrane to regulate water flow into the ground so as not to overflow the soil and cause waterlogging.

A property’s drainage system directs rainwater to the soakaway and as the downpour gets heavier, water starts to fill the hole. The filling component makes sure that the water percolates back into the ground at a reasonable rate.

The Installation Process:

You can construct a soakaway by yourself but there are a few considerations to consider before you start.

Contact the planning office in your area:

Check local planning laws before assessing the soil or the land. Especially if you’re planning to include the soakaway in an addition or extension to your property. Installing a soakaway is not possible in some locations because they are protected or close to a watercourse. You can carry out your plan after you receive confirmation that a soakaway is permitted.

Soil Percolation Test:

To estimate your soil’s rate of absorption, it is advisable to start by doing a soil percolation test. If the soil is excessively soft, it will hold onto the water instead of releasing it, eventually rendering the soakaway worthless.

Checking the Installation:

After determining whether a soakaway is practical, you can search the area for cables and pipes. Be careful about any type of electrical wire, gas mains, water mains, and even street lighting cables. Harming any of these when building your soakaway could prove to be very expensive.

Where should I install the soakaway:

Always check your local authority’s building laws before constructing a soakaway. Before you start the installation, it is vital to be aware of any local requirements as some rules specify where surface water must be collected and treated.

We advise building a soakaway at least five metres away from your residence. Do this once you are confident it complies with building codes. Remember that the longer the pipes must be to reach your soakaway from your property, which could increase the likelihood of blockages over time and raise the cost of construction. This could be worth the extra expense if you want to maintain your soakaway at the bottom of the garden where you can build a patio or deck.

What materials will you need?

Invest in silt traps, geotextile membranes, and soakaway crates to make installation as simple as feasible. These will not only make installation easier, but you’ll also notice that the longevity of your soakaway will increase.

Attenuation crates: 

Attenuation crates are useful for regulating the amount of surface water, especially in flood-prone locations. A system that reroutes water at a more convenient flow rate can be built using crates, waterproof geotextile, and piping. By encasing attenuation crates in permeable geotextiles, surface water stagnation is reduced by water slowly leaking into the surrounding soil. Soakaway crates are modular and can be stacked on top of one another and positioned next to one another. This means you may design a system that fits your spaces’ needs.

Geotextile membrane: 

High permeability fabrics called geotextile membranes (geotextiles) can keep undesirable contaminants out of drainage systems. Geotextiles that are non-woven work best for filtration or drainage and are simple to install. Simply wrap the geotextile cloth over each side of your soakaway crate and secure with staples or durable tape.

Silt Traps: 

By including a silt trap, you can increase the drainage pipe’s effectiveness and durability. It lessens the likelihood of blockages, flooding, and damage by preventing debris and silt from amassing inside the drainpipe. The crates are easy to maintain and are accessiable when needed. Overall this will increase the lifespan of the soakaway system.

How to select and install your attenuation crates:

The process of installing an attenuation is quite simple. The first steps would be to select the appropriate type and correct quantity of attenuation crates. If you don’t install the correct system for the level of rainwater, the attenuation create will become overwhelmed. This will result and in water backing up into the piping system over time.

Choosing the correct attenuation crates:

Since attenuation boxes are modular, you can tell how much water they can contain by looking at their technical specs. How much water you need to be able to keep in the attenuation crates will depend on cretain factors. These include: the results of your percolation test, the amount of room you have, the severity of any waterlogging issues, and the size of your accessible space.

Once you have calculated the volume of water expected, you can choose which attenuation create to purchase and how many you will need. Below are the different attenuation creates supplied by Polycon Water Management:

Installing an attenuation crate:

  • Excavate the area that will hold your soakaway crates to the proper size to start the installation process.

  • Create a trench to accommodate the drainage pipes that will transport surface water or rains to the soakaway.

  • Make sure there is enough permeable membrane to cover the top of the modular crates and to extend up the sides of the crate trench.

  • To prevent debris and silt from clogging the soakaway over time and making it ineffective, we advise installing a silt trap.

  • You must remove part of the membrane in order for the pipe to fit correctly where it needs to go. Look for the pipe entry point. In ideal circumstances, the membrane will flash the pipe.

  • A part of the membrane must be removed in order for the pipe to fit snugly. Look for the pipe entry point. In ideal circumstances, the membrane will flash the pipe.

How to tell if your attenuation crate is blocked:

One of the most evident signs of a blockage is waterlogging in the ground next to the soakaway. It may be difficult to determine what has blocked the soakaway because it is underground. Usually, one of these four explanations applies:

  • An accumulation of sediment and silt in the system.
  • Compacted Soil
  • Root intrusion from the nearby tree
  • System error, due to collapsing. 

The best method for avoiding clogs is to install your soakaway correctly. Although it may seem inconvenient, taking extra time and care during installation will wind up saving you time and money in the long run. Installing extras including silt traps, will reduce the amount of silt entering the system and therefore decrease the likelihood of blockages. This is another factor to think about when installing the attention create. 

If you’re apprehensive about installing a soakaway, you can hire experts to handle the task. A trustworthy contractor or business should be able to install a residential or commercial soakaway. They should be able to suggest how many crates you’ll need for the job. Getting the installation stage right will prepare you for the future due to the longevity of the crates.

To unblock your attenuation:

Unblocking your attention create is dependent on what is creating the obstruction. You can sometimes do it and other times you can’t. In the event that your soakaway does become clogged, it could be necessary to hire a professional.

High-pressure water jets can occasionally clear a build-up of silt and leaves in the piping. Although this approach only works in around 50% of situations, it is still advisable to be realistic about the result.  

The only solution in such cases is to replace any damaged sections of the pipe that have collapsed or been pierced by tree roots. If you were confident in your ability to install the soakaway system, you might think about performing this task on your own.

Before updating your soakaway system, make sure your building’s insurance coverage is up to date. If it isn’t, it is likely that you will have to cover any costs of repairing or replacing certain components,. For any more information surrounding our attention creates or any other method of storm water management, do not hesitate to get in touch. To do so you can call us on 0151 422 9747 or alternatively email us at

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