What are sustainable drainage systems? They're not just a necessity — they can also protect your home as well as improve its kerb appeal, say the experts

Whether you have noticed water pooling on your driveway, regularly have a waterlogged garden come the rainier seasons or are in the process of re-landscaping your home, you really should be thinking about improving the drainage on your property.

You may well have noticed a push towards sustainable drainage methods if you have been researching driveway materials, or are building an extension, with many local councils now keen to push homeowners towards solutions that reduce the risk of surface water escaping onto roads and pavements.

While many people still view sustainable drainage systems as the reserve of public spaces, increasingly, homeowners are getting on board with these methods, implementing them into their own home design, recognising not only the immediate benefits but also the wider positive impact incorporating even just elements of these designs can have. These are the options most worth considering.

What is a sustainable drainage system?

Sustainable drainage systems – also known as SuDS – are basically designed to mimic natural drainage as much as possible with the aim of reducing surface water and, subsequently, pressure on the existing sewer infrastructure. That said, many will also work to improve drainage in a garden and add something visually to your outdoor spaces too.

'Our towns and cities are at risk of flooding. In built-up areas, surface water collects quickly and can overflow drains. To put it plainly, the places we live just aren’t as ‘spongy’ as we’d like,' explains Adam Boucher, Network Operations Lead at Severn Trent. 'SuDS are Sustainable Drainage Systems. They work by diverting surface water away from sewers, slowing it down and helping our drains to cope. The great thing about SuDS is that they combine some of the latest water drainage technology with Mother Nature.'

While many sustainable drainage systems are designed for use within urban developments and commercial spaces, there are a whole host of ways homeowners can introduce them into their own homes too. By doing this, not only are they helping the wider surroundings, but can also enjoy other benefits.

Permeable paving

It might be that you are looking to refresh your driveway ideas, or that you are constructing a new drive completely from scratch – whichever it is, this is one area that sustainable drainage will often be a requirement.

'A lot of local councils now push Sustainable Drainage Systems, so they’re keen on permeable block paving, gravel and set-ups where water is stored and allowed to soak away slowly rather than racing into the drains or flooding the road,' explains Jack Hamer, managing director at Silvermere Landscapes. 'Nine times out of 10 on a typical domestic driveway in Surrey we will be designing the falls and drainage so that all the surface water stays within the plot. We will either ensure it either soaks away or runs into a suitable drain that’s allowed to take it.'

Using permeable materials also means that planning permission for a driveway won't usually be required, as well as ensuring the area doesn't end up full of puddles during periods of heavy rainfall.

Jack Hamer

Jack is managing director of Silvermere Landscapes, a Surrey based landscaping firm known for designing and building high end outdoor spaces. With a background in both hard and soft landscaping Jack has a strong eye for detail and a practical approach that keeps projects looking good and performing well for years. He oversees everything from concept and design through to construction and planting and is regularly asked for expert insight on garden design materials drainage and creating landscapes that balance style with function.

Shop permeable driveway materials

Soakaways

Another simple sustainable drainage option for homeowners is a soakaway, a method of taking excess rainwater away safely and prevent flooding, both on driveways as well as in gardens.

'Soakaways are considered a form of Sustainable Drainage System (SuDS), which are encouraged under both national and local planning policies,' explains David Iddon director at DTS Property. 'A soakaway is a subsurface drainage system that allows rainwater and surface runoff to percolate back into the ground, helping to prevent flooding and overloading the local drainage system. It’s typically a gravel-filled pit or modular crate system connected to a drainage pipe that collects water from roofs, patios, or driveways.'

There are kits readily available for homeowners which contain everything needed to install a soakaway on a DIY basis and, once in place, they are barely visible so won't ruin the kerb appeal of a property.

David Iddon

David founded DTS property in 2018 and the team is now made up of skilled and trusted builders, alongside a reliable network of tradesmen, that deliver building projects for local clients in and around Milton Keynes, Buckinghamshire, Bedfordshire and Northamptonshire.

Rainwater harvesting systems

While this might sound complicated, rainwater harvesting can be as simple as incorporating a water butt into the design of your home. By simply connecting a water butt to the guttering in order to capture rainwater run-off from a roof, you are preventing it from pooling on the ground – plus you can then use it to water your garden in a dry spell.

Other, more complex solutions, collect rainwater before directing it to a filtration system and, finally, into a storage tank. From here, depending on the type of system you have opted for, the water can be used for household tasks such as washing clothes and flushing toilets.

If you want the water to be suitable for washing and drinking, a far more elaborate system will be required.

Rain gardens

Another commonly used method of public spaces that translates beautifully into residential settings is the rain garden. This is a great way to reduce water logging, avoid the need for a soakaway and can also help attract wildlife to your garden.

'Rain gardens use plants and soil to retain and slow the flow of rainwater from surrounding hard surfaces,' explains Adam Boucher. 'They also help cool urban areas in the summer, so even when it’s not raining, they make a positive difference. '

According to the RHS, rain gardens are suitable for any garden which is relatively well-drained and that has a minimum slope of 10%.

These are basically shallow dips created in the ground ready to receive water run-off from hard surfaces and roofs. They can be planted with species that enjoy a good soaking such as flood proof plants and collect rainwater, allowing it to slowly disperse.

Do you have to have sustainable drainage?

At present you do not have to incorporate SuDS into your home, although if you are creating a new driveway over 5m2 in size and won't be using permeable materials, you will need to ensure water drains away to a suitable permeable area such as a French drain or soakaway.

Additionally, if you are building an extension, you will need to make sure you understand the building regulations surrounding dealing with excess surface water.

'When you add extra roof area or paving as part of your extension, it increases the amount of impermeable surface on your property,' explains David Iddon. 'This means more rainwater runs off rather than soaking into the ground naturally. UK Building Regulations require this additional surface water to be managed appropriately to avoid contributing to local flooding.'

This might mean incorporating a soakaway into your design, although this won't always be suitable, particularly if your property sits on heavy clay soil. Having a percolation test carried out during the planning stages will help determine the best solution for you.

What are the pros and cons of sustainable drainage?

There are many benefits for homeowners who implement sustainable drainage systems into their home – so don't just view them as boring requirements.

Pros of SuDS

• Helps reduce pooling and flooding on driveways and patios.
• Reduces the risk of a garden becoming waterlogged.
• Some systems will attract wildlife into your garden.
• Rainwater harvesting systems can cut your water bills.

Cons of SuDS

There are not many downsides to sustainable drainage, save for the fact that they do come at a cost. That said, driveway materials such as gravel and permeable block paving are not much more expensive than non-permeable materials such as tarmac.

FAQs

Are sustainable drainage systems expensive?

They don't have to be. Simple methods such as installing a water butt are very affordable. Likewise, one of the most permeable driveway materials around – gravel – also happens to be one of the lowest cost.

If you want to incorporate a soakaway, its size, location and who you choose to install it will play a part in its final cost. Expect to pay from £800 up to £2,500 for materials and labour.

Good drainage is so important when it comes to preventing damage to your home, but there are lots of other ways of floodproofing a house to consider too for a multi-faceted approach.