Welsh Government post-implementation review of Schedule 3 of the Flood and Water Management Act 2010

Flooding, Management & Regulation, Processed Water

After a decade of consideration, Schedule 3 of the Flood and Water Management Act (FWMA) 2010 was commenced in Wales in 2019. We catch up with Arup who led a review of the Welsh Government’s new framework

Schedule 3 provides a framework for approving and implementing sustainable drainage systems (SuDS). It introduces the SuDS approval body (SAB) role for local authorities, and national standards that cover aspects of design, construction, operation and maintenance.

In January 2019 the legislation was implemented in Wales in response to the increasing risks of urban flooding and watercourse pollution experienced in towns and cities – a result of increasing urbanisation, population growth and climate change.

The legislation also more broadly supports Welsh Government’s future generations and environmental commitments. Four-years in and the framework for delivering sustainable drainage has been put to the test.

The review spanned ten-months and included desk-based analysis, large-scale engagement events, questionnaires, and targeted discussions. Feedback captured from over three hundred organisations and individuals informed recommendations.

Whilst focused on Wales, the findings will be of interest to stakeholders in England where implementation is expected in 2024.The review highlighted progress made and gathered evidence to shape things going forward.

The legislation and associated Statutory Standards promote sustainable water management integrated into communities and support nature recovery through favouring green infrastructure solutions. Welsh Government’s objective is to promote the delivery multi-purpose SuDS in new development that will remain effective – and we’re beginning to see the benefits of this across Wales.

Pictured above: Greystone Meadows Undy, Monmouthshire (Image credit Bellway Wales)

The Welsh Government Minister for Climate Change has committed to:

  • Amend the national SuDS standards for Amenity and Biodiversity to align with wider policy objectives
  • Provide options and timescales to increase capacity building and the delivery of further training for SuDS Approval Bodies (SABs)
  • Investigate the practical implications of new standards for the inclusion of SuDS design elements within new and existing highways
  • Investigate and develop the best mechanism for annual data collection and reporting by SABs
    Combine guidance into one clear document, consistent with the legislation and Standards to close gaps, ambiguity and inconsistency
  • Reinvigorate a SuDS advisory group with focus on delivery, sharing lessons learnt and best practice.
  • Scope, cost and procure a national commuted sums approach, possibly to include rates and length of maintenance period, and associated guidance
  • Develop an action programme, detailing short, medium and long-term delivery targets covering wider recommendations.

Other priority short-term recommendations:

  • Introduce standard legal forms
  • Develop a national commuted sums approach
  • Consider the desirability and viability of a service charge approach as a mechanism of funding long-term maintenance of adoptable SuDS assets
  • List scenarios that do not require SAB approval to support a proportionate risk-based approach
  • Develop a consistent pre-application process which includes binding SAB advice

Review recommendations

Unsurprisingly there have been some challenges highlighted through the implementation phase. 17 themes emerged, grouped into four categories, as pictured below.

The Welsh Government is developing an action programme, detailing short, medium, and long-term delivery targets. In this article we summarise some key themes and recommendations. You can see a full copy of the review findings and range of recommendations on the Welsh Government web page.

"Throughout the Review, all stakeholders recognised the positive outcomes Schedule 3 set out to deliver. Issues that have been identified predominantly relate to the delivery process and procedure. It should be recognised that local successes often stem from a collaborative, “yes, if” approach by all parties, underpinned by the legislative framework." - Julie James, Welsh Government Minister for Climate Change

Skills and experience

Resource and skills gaps within the industry are highlighted as significant (including within SAB departments). Not only does this apply to technical design; there is a need for more environmental specialists, landscape architects and inspectors with the knowhow of implementing SuDS. The same applies to those building and maintaining SuDS.

Forming regional SAB partnerships could foster rewarding career pathways whilst balancing resource demands and providing access to specialists. Ongoing training is required within the industry. Combined with pooling resource there should be a focus on developing new talent by promoting SuDS skills through tertiary education with specific course content. These recommendations are a priority for the Welsh Government.


The approach to and acceptance of SuDS in highways is inconsistent across Wales, and for the most part the benefits of SuDS are not maximised in highway settings. This requires improved guidance and standards to maximise wider benefits and that complement Active Travel and other Welsh policy e.g. 20mph default speed limit coming into force in September 2023.

The Welsh Government will investigate the practical implications of updating standards to include SuDS within new and existing highways. This may draw on examples of existing local guidance and reference case studies, and should address the perceived barriers to SuDS in and adjacent to highways.

Governance and performance

Introducing an overseeing organisation would improve consistency and promote good practice. There is also a need for a transparent performance framework, informed by consistent yet proportionate data-gathering from SABs. This exists for the well-established Planning process and has encouraged continual improvement.

Maintenance funding

Funding long-term maintenance of SuDS has been discussion point long before Schedule 3 was commenced. In Wales, the SAB adopts drainage systems that serve more than one property – a commuted sum is the common mechanism for calculating associated costs. The review highlights inconsistencies in the maintenance periods and rates used across Wales, but also that commuted sums can be cost-prohibitive from the outset. Having certainty on maintenance funding when planning a development’s affordability is key for developers. A consistent commuted sum approach is recommended, whilst alternative funding mechanisms are also to be investigated e.g. a service charge or hybrid approach.


Current technical requirements are challenging for some types of development, with a general view that the technical standards are well-suited to typical new housing developments but can be unclear or inappropriate when applied to other types of development like temporary structures. There should be a proportionate risk-based approach to development in-keeping with the intention of the legislation, without inhibiting or disproportionately burdening small development activities or infrastructure improvements. Consideration should be given to ‘deemed to comply’ scenarios and ‘lite’ approaches for some types of development.

Biodiversity and amenity

Improving the environment and creating spaces for people in and around blue-green infrastructure is the direction of travel in Wales. Schedule 3 strengthens a Welsh Government commitment for the use of SuDS that provide wildlife habitat. Evidence obtained through the review demonstrate that this is working and there is a feeling that biodiversity improvements are being delivered when compared to elsewhere.

Pictured above: Live Event engagement response to ‘do you think drainage design is delivering improved biodiversity in your area?’

However, the Biodiversity and Amenity Standards do not currently set thresholds or targets, and instead state that benefits should be ‘maximised’. Whilst every site and solution is unique, feedback is that the requirements are too vague and lead to differing interpretation. Further clarity is recommended which should include aligning the Standards with wider policy objectives e.g. Planning policy in Wales targeting biodiversity net benefit.

Pre-application advice

The review included a more in-depth look at the optional SAB pre-application process. A more consistent approach is needed, perhaps making it mandatory for some types of development, and introducing a consistent charging structure. The pre-application process should be aligned with appropriate stages in the planning process (where applicable).

Feedback showed that undertaking a pre-application phase made the final determination more successful, demonstrating the value of early investment. This is echoed by the experience of Welsh Government’s Ian Titherington in the June edition of The Environment. Facilitating a lower final application fee where a pre-application fee has been paid could encourage the uptake of the service while acknowledging the reduced input for final determination.

Chris Ellis is stormwater and green infrastructure leader at Arup and led the post-implementation review. The team included specialists Dan Tram and Robin Campbell from Arup, and Michelle Russ seconded from Morgan Sindall.

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