Sustainable drainage systems (SuDS) on Welsh new developments are now mandatory

New legislation from the Welsh government, which came into effect on January 7, 2019, stipulates that all new developments of more than one dwelling or where the construction area is 100m2 or more should have Sustainable Drainage Systems (SuDS) in place.

From this date onwards, SuDS on a new development must be designed and built in accordance with the Statutory SuDS Standards published by the Welsh Ministers, while SuDS schemes must be approved by the local authority acting in its SAB role, before construction work begins.

Alumasc WMS says it believes water management should be considered from the beginning of the development process and throughout, and that it should positively influence the design and layout of the project or space.

So, how can you implement SuDS in your project when it comes to roofing and water management?

The core aim of SuDS is to manage rainfall in a way as similar to the natural process as possible, making use of surrounding landscape and natural vegetation to control the volume and flow of surface water. The benefits of SuDS can encompass flood risk reduction, enhanced biodiversity, creation of natural habitats for wildlife, contribution to better mental health and much more.

Both Green and Blue Roof systems offer SuDS measures, intended to significantly reduce peak rates of rainwater runoff, especially during heavy rainfall. This is not limited to during the event of a storm. As a general rule in the UK, London and East Anglia receive high intensity rainfall incidents, whereas western aspects of the UK generally receive higher total rainfall. So, its not just Cardiff, officially the UK’s wettest City, but the whole of the UK that would benefit from Green and Blue Roof technology.

Green and blue roofs do this is in different ways but can be used in conjunction with each other. Blackdown Greenroofs, for example, retain rainwater through plant absorption and provide replacement of lost animal habitats through the introduction of natural vegetation, occupying otherwise redundant roof space and providing a great opportunity to create new amenity space for people to use for recreation and increased overall wellbeing—a real benefit in dense urban spaces.