SuDS - Sustainable Drainage Legislation on New Developments Becomes Mandatory in Wales

James has recently completed Sustainable Drainage System training course in London provided by CIRIA. helping to reinforce Castell Bach Engineering Ltd.'s ability to serve Clients with their developments in Wales.

As of 7th January 2019, all new developments in Wales of more than 1 dwelling house, or where the construction area is 100m2 or more, will require Sustainable Drainage Systems (SuDS) for surface water.  (

As of this date, SuDS on new developments must be approved by a Sustainable Drainage Approval Body (SAB), before construction work begins. Each local authority in Wales will have a SAB set up, with each authority rolling out the scheme with immediate effect. (

SuDS aim to manage rainfall in a way similar to natural processes, making use of the landscape and natural vegetation to control the flow and volume of surface water. SuDS help engage with developers and project stakeholders by creating a mindset whereby water is considered as a resource to be managed at source.

Not only is it now a requirement in Wales, but there are many benefits to introducing SuDS to a new development including:

  • flood risk reduction;
  • improved water quality;
  • opportunities for habitat creation;
  • enhanced biodiversity;
  • contribute amenity and aesthetic value to development;
  • potential cost savings (capital and operational).

Castell Bach Engineering Ltd. can support developers, landscape architects and consultancies in meeting the new SuDS requirements by providing assistance throughout the entire project lifecycle from concept drainage schemes through to detailed drainage design and construction completion.  Castell Bach Engineering Ltd. has recently produced Drainage Strategies on a number of different projects supporting Clients through the new SAB process and we look forward supporting existing and new Clients with their future developments.