SuDS general design guidance

National Planning Policy requires Local Planning Authorities to ensure that flood risk is not increased due to development. To ensure that developments are adequately drained, we expect surface water drainage to be designed in accordance with The SuDS Manual C753 by CIRIA and the National Standards for Sustainable Drainage Systems (SuDS) - NSfS.

It is expected that all surface water drainage designs submitted to support new planning applications comply with the NSfS. Where the scale and layout of a development have been decided by a full or reserved matters planning application prior to 19 June 2025, we will expect the design to attempt to meet the requirements of the NSfS. However, where this is demonstrated not to be possible, a departure from the standards may be suggested.

Our consultations and checklists are designed to align with the NSfS as they are the most recently published national guidance. We recognise that there are some areas where the publication of these standards represents a change in expectation, however, many of the standards broadly reflect the guidance of The SuDS Manual.

These pages aim to offer clarity and pre-empt questions relating to the interpretation of these two sets of guidance. We do not intend to replicate these documents; all designers are directed to refer to them as their primary source material for design guidance.

Page last updated

26 November 2025