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SuDS Approval Body (SAB)

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All new developments of more than 1 house or where the construction area is of 100m2 or more require sustainable drainage to manage on-site surface water. Surface water drainage systems must be designed and built in accordance with mandatory standards for sustainable drainage published by Welsh Ministers.

These systems must be approved by the local authority acting in its SuDS Approving Body (SAB) role before construction work begins. The SAB will have a duty to adopt compliant systems so long as it is built and functions in accordance with the approved proposals, including any SAB conditions of approval.


Schedule 3 of the Flood and Water Management Act (FWMA) 2010 requires surface water drainage for new developments to comply with mandatory National Standards for sustainable drainage (SuDS).

Schedule 3 to the FWMA 2010 also places a duty on local authorities as SuDS Approving Body to approve, adopt and maintain systems compliant with section 17 of the Schedule. For further information on the legislation, please see Schedule 3 of the Flood & Water Management Act 2010. You should also refer to CIRIA 753: The SuDs Manual.

What is a SAB?

The SAB is a statutory function delivered by the local authority to ensure that drainage proposals for all new developments of more than 1 house or where the construction area is 100m2 are designed and built in accordance with the national standards for sustainable drainage published by Welsh Ministers.

The SAB is established to:

  • evaluate and approve drainage applications for new developments where construction work has drainage implications, and
  • adopt and maintain sustainable surface water drainage systems according to Section 17 of Schedule 3 (FWMA)
  • the SAB also has powers of inspection and enforcement
  • and uses discretionary powers to offer non-statutory pre-application advice

What does it mean for my development?

Whether you are a developer, an agent or an individual seeking planning permission for a development, if your development is of more than 1 house or of 100m2 or more of construction area you must also seek SAB approval alongside planning approval. You will not be allowed to start construction until the 2 permissions are granted.

Existing sites and developments with planning permission granted or deemed to be granted (whether or not subject to any conditions as to a reserved matter) or for which a valid application has been received but not determined by 7 January 2019, will not be required to apply for SAB approval.

However, SAB approval will still be required if the planning permission was granted subject to a condition as to a reserved matter and an application for approval of the reserved matter is not made before 7 January 2020.

Some exemptions will apply:

  • construction work which does not require planning permission is excepted from the requirement for SAB approval, the exception does not apply where the construction covers an area of 100 m2 or more
  • whether or not planning permission is required, construction work involving the construction of a single dwelling house, or other type of construction, which covers an area of land of less than 100m2, is excepted from the requirement for approval

SAB approval

SAB pre-application merged with LPA pre-application process

The SAB will offer a chargeable pre-application service to discuss in detail your site’s drainage and what needs to be submitted with your application. This service will be offered with the planning pre-application advice should you wish to receive it. This will ensure suitability of proposed SuDs design in line with national standards and adequate site layout. This service will be valuable to developers to help limit delays and reduce costs in the long term.

Full-applications must be submitted to the SAB for validation and must be accompanied by:

  • a plan specifying the construction area and the extent of the drainage system,
  • information on how the construction work will comply with the SuDS Standards;
  • information requested in the application form checklist
  • the appropriate application fee.

The SAB will have 7 weeks to determine applications other than those requiring an Environmental Impact Assessment, in which case it has 12 weeks.

All submissions will need to be made to the relevant SAB.

Contact the SAB

SuDS Approval Body (SAB)
(01639) 686850 (01639) 686850 voice +441639686850

Further information