New national standards for sustainable drainage systems

Standard 1 of the new national standards places a greater emphasis on prioritisation and evidencing the choice of final run-off destination. It strengthens the position that runoff will  be treated as a resource and gives priority for the collection of runoff for non-potable use. Then considering other discharge destinations following the hierarchy. The use of the runoff locations should be used where they are viable in parts of a site, rather than being ruled out across an entire site.

The remaining six standards 2 to 7 state minimum design criteria that all surface water drainage systems should meet. These include the everyday rainfall, management of extreme rainfall and flooding, designing for multi-functional benefits. This includes the management of water quantity and quality, biodiversity benefits and amenity value, and promoting good construction, operation and management practice throughout its lifetime.

Underpinning the standards are eleven principles for the natural approach to managing water, early and integrated design and links with development planning.

The full standards can be found on GOV.UK.