Schedule 3 – why we can’t afford to wait for legislation to catch its tail

31 January 2025

Why this could be a pivotal year for water and drainage management legislation and how the sector can prepare for what lies ahead

The UK government is seriously ramping up efforts to reform the water industry, focusing on enhanced environmental protections and increasing regulatory oversight. After years of delays and confusion around the implementation of Schedule 3 of the Flood and Water Management Act 2010, developers are naturally considering how (or even if) this legislation will eventually influence and guide their projects.

Despite promises to enforce the mandatory adoption of sustainable drainage schemes (SuDS) by 2024 through Schedule 3, regulations remain stalled, raising concerns among environmental groups and industry stakeholders about the government’s commitment to sustainable water management.

Whether we see the act come into force in 2025 or not, the spotlight on the role of SuDS has changed planning for good and brought sustainable drainage to the forefront.

Drowning in delays

Schedule 3, which requires all developments to include SuDS for planning approval to be granted, was first postponed in 2014. For the last decade, leaders from across the built environment have been calling for its implementation and in 2024 hopes were initially high for its implementation in April 2025.

While that was not to be the case, promisingly the UK government has made clear its commitment to reforming the water industry. By placing a stronger emphasis on environmental protection and regulatory oversight, ministers have signalled their dedication to driving change within the sector. As part of this broader agenda, the government remains firmly committed to requiring standardised SuDS in new developments, with a final decision on the way forward expected in the coming months.

The role of SuDS

This winter the UK has already faced a number of extreme weather events that have threatened people's homes and caused significant surface water flooding. While SuDS won't mitigate the impact of once-in-a-generation weather events, they do play a role in lessening the impact of surface water flooding and helping communities adapt to changing weather patterns.

Flash floods are hard to predict, but climate experts have calculated that the number and severity of flooding is set to spike further – due in part to the rise of sudden, heavy rainstorms triggered by climate change. Coupled with the impact of urbanisation and a growing population, the unpredictable weather puts severe pressure on traditional drainage systems, many of which date back to the Victorian era. The enactment of Schedule 3 is long overdue and necessary to address these challenges effectively.

SuDS are designed to manage water runoff from properties and developments, addressing surface water floods by slowing the flow of water and allowing pollutants to be naturally filtered through permeable surfaces, wetlands and grassed areas. This approach offers long-term, sustainable and efficient water management, essential for our changing environment.

Getting ahead while remaining compliant

It’s clear that across the industry – everyone from trade bodies to people working on site – there is a strong desire for the introduction of Schedule 3. While uncertainty around the long-awaited implementation date remains, this does give the industry a chance to get ahead.

To avoid future issues, developers should actively seek to educate themselves on the systems currently available, rather than rest on their laurels and wait for a framework for the approval and adoption of SuDS. This will allow them to adapt confidently once the legislation is introduced.

If Schedule 3 is finally implemented, developers will not only be required to include SuDS in new developments but will be required to ensure that designs are approved before construction begins. Approval will be managed by a SuDS approving body (SAB), with all designs required to meet national standards focused on water quality, biodiversity and flood prevention.

Credit: Wavin

This requirement will impact design, costs and approval timelines. Developers will need to incorporate features like permeable paving, green roofs and rainwater harvesting systems into their designs. The approval process may also be lengthened, as SABs assess compliance with national standards. Although incorporating SuDS may come with initial perceived negativity around areas such as initial cost increases, the long-term savings on drainage infrastructure and maintenance may offset these.

However, impending legislation requirements will differ between projects, so developers should get ahead and ensure they’re clued up on which system is right for the size and nature of the projects they deliver. Local authorities will also require sufficient evidence that proposed developments will meet the current building standard when making the necessary applications for planning approval. This will involve cost considerations around SuDS designs and fees for ongoing inspection while the development is in progress.

Collaborate for success

Legislation changes can feel overwhelming – particularly those of this magnitude. However, when it comes to Schedule 3, developers needn’t bury their heads in the sand. Collaboration is key, and by working in partnership with specialists, developers can learn how best to combine sustainable blue and green systems with existing grey infrastructure to deliver optimum results.

By adopting a proactive approach, developers can turn Schedule 3 compliance from a regulatory hurdle into an opportunity to lead in sustainable development.

For more information about SuDS, visit https://wavin.com/en-gb/solutions/stormwater   

Author: Martin Lambley, global product manager for urban climate resilience at Wavin