Flooding – SuDS It Up

Catastrophic storms used to be infrequent, part of our history, but now it seems that we hear about the results of such events every other year.  Sadly, we are guilty of making the results of these events worse as more people move into cities and towns – in Britain more than 80% of us live in Urban areas.  Our increasingly impermeable grey landscape simply cannot cope with large volumes of water in the same way as the rural green areas.

Tarmac and traditional paving surfaces mobilise water. Instead of soaking into the ground, the water simply runs along these surfaces often gaining in volume. Too often the only answer is directing it to an out-of-date storm water network that is often unmaintained.  Just look at how many drainage grids are blocked up with leaves and silt that has been swept along the road by the very same flood water.

Soak it up with SuDS

The principle of SuDS is simple.  Instead of redirecting rainwater it soaks it up where it lands, cleans it and slows the speed at which it moves.  It mimics the way that our natural habitat would deal with rainfall and has to be the answer for our urban spaces.

While SuDS encourages more green space in urban areas, which in itself is a great thing, we still need hard surfaces to drive, cycle and walk along. The answer is to install permeable paving which is a proven and thoroughly tested solution to managing storm water.  Our Formpave solution for example collects, cleans and stores ground water to significantly reduce the impact of large rainfall events.

It behaves in the same way that your lawn would, but with the added benefit that you can drive your car, van or even lorry across it.

Are you ready for the SuDS train?

This of course is just part of the solution and a good SuDS system will incorporate all sorts of measures pertinent to the local development.  This may include linear wetland adjacent to roads, swale, wetland ponds and other bioretention solutions such as green roofs.

Often you will need to combine multiple SuDS techniques to manage water and when used together such solutions are known as a SuDS train.  More and more engineers, designers, architects and town planners are planning such systems to create more sustainable developments.

More than a tick box

Sadly, until recently SuDS was too often just a tick box exercise and would often be taken out of a specification to either save cost or because people are not trained in how to design and install such systems.

Until we address this shortfall, we will continue to see images of people having to abandon homes and as a society we will have to pick up the cost.

Fortunately, legislation appears to be driving this very real need for action and SuDS could soon become mandatory in England with local authority “SuDS approval bodies (SABS)” checking compliance as they already do in Wales.  In the face of obvious issues in many of our urban landscapes, there is mounting pressure for the government to proceed with this and it will probably enforce the legislation in England by the end of 2023 – so watch this space.

And there is also more than enough resource to help specifiers and installers of such systems. A good place to start is the CIRIA publication, “The SuDS manual (C753”).

There are already too many impermeable urban areas suffering from floods.  Let’s not add to the problem as we continue to develop as a society.  It’s high time we all caught the SuDS train.

If you would like to know more about the role that permeable paving plays in SuDS then sign up to our CPD accredited training session “Formpave Aquaflow SuDS Systems” – https://www.forterra.co.uk/technical/specifier-academy/technical-cpd/