Interim non-statutory standards for sustainable drainage (SuDS) in Wales - designing, constructing, operating and maintaining surface water drainage systems

The SuDS approach to surface water drainage provides an alternative to conventional piped drainage. It typically uses combinations of installations such as permeable paving soakaways green roofs swales and ponds and can be used effectively in both rural and urban areas to support new development.

This approach can slow down the flow of water contributing to a reduction in flood risk and protecting water quality. Reduced runoff to sewers provides additional capacity without expensive engineering work whilst more natural systems improve water quality and  the environment.

It is vital that adoption and management arrangements for SuDS infrastructure and all drainage elements are agreed with the local authority or sewerage undertaker at the planning stage to ensure that SuDS infrastructure is properly maintained and functions effectively for its design life.

The Flood and Water Management Act 2010 (Schedule 3) which has not been commenced requires new developments to include SuDS features that comply with national standards. The Welsh Government proposes to publish interim national standards on an advisory basis until such time as it determines the most effective way of embedding SuDS principles in new developments in the longer term.

This will enable designers property developers local authorities and other interested parties to both demonstrate that they have taken account of the Welsh Government’s planning advice on Development and Flood Risk and to pilot the standards so that if necessary they can be revised before being placed on a statutory footing.