Planning developments with drainage impacts

We require detailed information to be submitted with any planning application which has drainage implications. This is because we have to give a detailed assessment of the foul and surface water drainage impacts of developments and uses requiring planning permission, as material considerations when determining planning applications. This includes evaluation of any flooding implications.

What do you need to provide with your planning application?

To help assess the drainage impacts of a development and to avoid any delays in the consultation process with technical bodies such as Natural Resources Wales, Dwr Cymru Welsh Water and the Council’s drainage engineers, we have developed a Drainage Strategy questionnaire which should be submitted with any planning application.

Sustainable Drainage Systems (SuDS) are a mandatory requirement on all new developments involving more than a single dwelling or a construction area more than 100m2. You must apply to the SuDS Approving Body (SAB) for approval on these types of developments.

We recommend that you complete a drainage strategy questionnaire before applying for SuDS approval.

Find out more about SuDS including how to apply for approval.

Drainage Strategy questionnaire

The Drainage Strategy questionnaire deals with foul and surface water drainage matters, and sets out questions you need to answer to confirm the proposed arrangements, and asks for the case to be justified for the choice of systems.

You may need to provide a separate technical Drainage Impact Assessment to support the information in the questionnaire and supporting plans or documents.

Please speak to a specialist drainage consultant if you would like more information on what to provide with your application.

Download the Drainage Strategy questionnaire