How SuDS in Schools is reducing the risk of surface water flooding

26 June 2026

How installing sustainable drainage in school playgrounds is reducing the risk of surface water flooding and inspiring the next generation of water professionals, by Sophia-Harri Nicholaou, a senior flood risk consultant at WSP

Wastewater treatment is a biological process. While we know that there are certain families of bugs that do certain jobs, we don’t really know which specific microbes are doing what, and where they thrive.

When the skies opened over Westminster in July 2021, the floodwater didn’t creep – it surged. More than 550 homes and businesses were hit, and among them were several schools suddenly engulfed by surface water flooding. Playgrounds vanished under murky water, school grounds were saturated and the rhythm of daily life was thrown off course as staff and pupils grappled with the shock of a once‑in‑a‑generation rainfall event.

These schools stood as stark reminders that even the most ordinary day can be upended in minutes when the drainage network beneath our feet is pushed beyond breaking point. Across London’s dense urban landscape, the challenge of managing surface water flooding is growing – but so is the opportunity to rethink how communities engage with climate resilience.

Four years after that flooding took place, a collaborative project between Westminster City Council (WCC), WSP, FM Conway and Meristem Design sought to ensure that such disruption will never happen again. The project, SuDS in Schools, responded to two interlinked challenges: increasing surface water flood risk in urban environments; and a growing need to build skills, awareness and public understanding around sustainable water management. Using schools as sites for both infrastructure delivery and learning demonstrates how these challenges can be addressed together.

Collaboration at the heart of delivery

In 2025, WCC received funding from the Department for Education (DfE)’s SuDS in Schools grant scheme to install 24 SuDS planters across five primary schools. Each of the project partners contributed specialist expertise, ensuring that technical, educational and operational requirements were aligned from the outset. For my employer, WSP, that meant technical expertise in flood risk modelling, feasibility and design to identify site-specific opportunities for improved drainage performance.

Meristem Design, a local supplier with ambitions to become a leading force in green infrastructure, supplied the SuDS planters. The civil engineering contractor FM Conway, a key partner to WCC, undertook minor drainage improvements such as non-return valve installations and visual manhole inspections where required.

The schools included in the project were chosen due to their high surface water flood risk or historic flooding, predominantly relating to the July 2021 flood event. Early engagement with schools ensured that safeguarding, curriculum priorities and long-term maintenance considerations were fully integrated into design and delivery, while close coordination between consultants and suppliers enabled high quality installation within the constraints of live school environments.

SuDS in Schools in numbers:

• 490 projects funded to date across England
• 309 projects completed
• 181 projects ongoing

Making SuDS visible and multifunctional

A key design principle is visibility. In many urban environments, drainage infrastructure remains hidden below ground, limiting opportunities for public understanding and engagement. This is especially true in inner London boroughs like Westminster, where constrained space forces most systems below ground through the combined sewer system. By contrast, SuDS planters create visibility and accessibility to drainage, fostering the role of SuDS as multifunctional infrastructure rather than single-purpose drainage assets.

Functionally, the planters intercept roof runoff, diverting flows away from traditional gullies and providing source control. Meristem’s SuDS planters manage rainwater runoff by channelling it through layers of vegetation and a specially engineered soil blend. This process allows the water to be gradually absorbed or released, easing pressure on conventional drainage systems and helping to mitigate flooding – the planter holds 94% of the rainfall that goes into it. Plants draw moisture through capillary action, allowing for sustained irrigation and this approach increases attenuation capacity on site – helping to reduce peak flows and ease pressure on the combined sewer network during intense rainfall events.

Learning by doing

Education was embedded as a core project outcome, with WSP leading interactive workshops with more than 150 pupils aged eight to eleven across the five participating schools. The workshops introduced pupils to flood risk management through concepts including the urban water cycle and pathways of rainfall; the causes and impacts of surface water flooding; and climate change and future rainfall uncertainty. The children learned about the functionality of sustainable drainage, why it is critical in dense urban areas, and how effective flood risk management relies on collaboration between engineers, consultants and designers.

For many students, this was their first exposure to engineering as a creative, problem solving profession linked directly to environmental outcomes. The experience not only captured their interest but clearly demonstrated the power of hands‑on learning to inspire a next generation of environmental stewards.

From design to delivery

The 24 SuDS planters were installed during the summer of 2025 while schools were closed, with planting workshops held at the start of term to involve pupils in the final stage of delivery. Working alongside the project’s partners, students learned about plant selection, seasonal change and habitat creation, as well as the importance of routine maintenance and long‑term stewardship. These sessions highlighted that the performance of SuDS relies on ongoing care as much as innovative design and construction, giving students a meaningful role in shaping features that will remain part of their school environment for years to come.

The pupils also designed their own artwork for the SuDS planters, transforming each unit into a vibrant showcase of their ideas about water, nature and resilience. Seeing their drawings brought to life gave the children a powerful sense of ownership – instilling the message that these were not just drainage features installed for them but shaped by them.

Engaging families and communities

Beyond direct educational outcomes, the project has strengthened engagement with the wider school community. Teachers are continuing to use the planters as learning resources across science and geography lessons, embedding water management into everyday teaching. Parents and visitors can also see how SuDS contribute to greener, more resilient neighbourhoods, helping to normalise sustainable drainage as a visible part of the urban environment.

The project has successfully supported WCC’s wider climate adaptation goals as well as helping to deliver their Local Flood Risk Management Strategy. The project has an important role in building public understanding and acceptance of SuDS, which is critical to wider adoption, especially as WCC accelerates SuDS delivery across Westminster.

Scaling success

Building on the success of SuDS in Schools in Westminster, WSP is now working with other lead local flood authorities (LLFAs), including Luton Borough Council and the Royal Borough of Kensington and Chelsea to help deliver similar school projects. These projects continue to place collaboration, education and engagement at their core, demonstrating how local authorities can maximise social value alongside statutory flood risk management responsibilities.

Now is the moment for other LLFAs to follow suit. Every school – regardless of size, site constraints or history of flooding – can realise measurable benefits from implementing SuDS. Even small‑scale interventions contribute meaningfully: every cubic metre of water storage reduces the pressure on already overwhelmed combined sewer systems. With around 3,500 schools in London and over 29,000 across the UK, the potential for widescale impact is enormous. Beyond reducing flood risk, SuDS deliver wider benefits: improving water quality, enhancing biodiversity, moderating temperatures, creating greener learning spaces, and offering powerful learning opportunities.

Inspiring young people to understand surface water flood risk – and to see themselves as potential future engineers, designers or environmental professionals – may prove just as valuable as the infrastructure itself. In this way, the SuDS in Schools project is helping to grow the climate-ready workforce of the future, one school and one planter at a time.

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This article appeared in the Summer print edition of The Environment. Become a member of CIWEM today to gain access to the quarterly magazine, as well as digital access via MyCIWEM. Non-members can also access the monthly The Environment digital newsletter.

Sophia-Harri Nicholaou is a senior flood risk consultant at WSP