Approval of Schedule 3 in England

February 2023

DEFRA have recently announced the approval of Schedule 3 of Flood and Water Management Act 2010. But what does this mean and what are the implications for developers and designers?

What is the Flood and Water Management Act 2010?

It is a piece of legislation introduced on 8 April 2010 in England and Wales. It was intended to implement recommendations following the review of widespread flooding in 2007. The Act was also a response to the need to develop better resilience to climate change.

The Flood act was implemented, but schedule 3 was only implemented in Wales.

What is schedule 3?

Schedule 3 was included in the Act and it proposed the introduction of SuDS, in order to:

  • Reduce damage from flooding.
  • Improve water quality.
  • Protect and improve the environment.
  • Protect health and safety.
  • Ensure the stability and durability of drainage systems.

What were the key aspects of Schedule 3?

  • The Government shall publish national standards for the implementation of sustainable drainage.
  • Construction work which has drainage implications may not be commenced unless a drainage system for the work has been approved by the approving body.

What’s going to change with the recent approval of Schedule 3 in England?

  • SuDS will be mandatory for all major development from 2024 (date to be confirmed).
  • New National Design Standards will be developed.
  • LLFA approval will be required for the construction of any drainage works.

What are the implications for developers and designers?

  • Developments will need to integrate ‘proper’ SuDS elements such as raingardens, swales, ponds… providing an attenuation tank to limit flows won’t be enough.
  • SuDS will have a significant impact on land intake and the overall feasibility of the development – early engagement with drainage engineers and landscape architect will be required.
  • An agreement with the sewer undertaker won’t allow developers to connect to sewer – compliance with SuDS Standards and final approval from the LLFA will be necessary.
  • Clear SuDS Requirements and design specifications are expected to be published, making it easier for developers and authorities to agree on the proposed solution.
  • Adoption processes are also expected to be smoothed out.


The approval of schedule 3 has been received with enthusiasm by drainage engineers, landscape designers and flood consultants. The publication of National Standards is meant to provide clarity on various aspects of the SuDS implementation process, that previously drag planning applications for longer than expected and often create confusion among the design team. Also, SuDS professionals are confident this a much-needed support in order to engage with developers who are sometimes reluctant to introduce SuDS unless strictly required and are skeptical about the benefits.

Words by Yaré Pérez

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