SuDS in Schools

SuDS stands for Sustainable Drainage System – a nature-based method to slow the flow of water,  preventing localised flooding and improving the quality of water entering our rivers.

SERT designed and installed ten bespoke rain garden planters on school grounds to store rainwater and slow the flow of rain to the drain, reducing localised flooding.

This was part of the SuDS in Suttons’s Schools Project led by the London Borough of Sutton aiming to alleviate flood risk in Hackbridge, Sutton.




  • Pupils learnt about SuDS


  • square metres of roof diverted from drains


  • people engaged with SuDS


  • SuDS planters


SuDS in Schools aims to:

A rain garden

Reduce flood risk by capturing runoff, and slowing the flow of rain to the drain.

One of our planters in bloom

Add amenity benefits to school sites such as planting, seating, wildlife and educational features.

SuDS Assembly

Educate pupils to improve their understanding of water management issues.

Engagement stall

Engage the wider community to gain widespread support for SuDS.

In a natural landscape

Approximately 90% of rainfall infiltrates into the ground where it is stored to be used by plants or soaks deep into the earth to replenish groundwater.  Only 10% of rainfall becomes runoff, flowing into rivers and other water bodies.

Water in a natural landscape © South East Rivers Trust

In an urban landscape

As much as 90% of rainfall enters the drains and only 10% is able to infiltrate into the ground.

Why is this a problem?

The drainage network under our feet has not been built to cope with this volume of water and can easily become overwhelmed, resulting in localised flooding.

Worse still for rivers, this runoff collects all the dirt and chemicals from our roads, flowing straight into a local stream with no treatment.

In some areas with a combined sewer system, rainwater entering the drain causes the Sewage Treatment Works to be overwhelmed, resulting in the discharge of untreated sewage into our rivers.

Water in an urban landscape © South East Rivers Trust

Designing with schools

Schools are busy places so our projects really needed to deliver without causing any disruption. We ensured true benefits to the school, the pupils and staff, and the environment, by involving everyone in the design process.

This included:

  • Staff surveys and meetings
  • Design drop-in sessions
  • Assemblies and lessons
Designing SuDS with pupils © South East Rivers Trust

Innovative planters

SERT installed ten SuDS planters across four sites and a range of materials, connections and features were tested.

Recycled plastic planters and metal water troughs were used to test the structure, different connections and pouring methods were trialed for different site conditions and school needs. Geocelullar crates were successfully used to increase planter storage capacity.

Additional features were added such as wildlife habitats, benches or sensory planting in response to school input.

SuDS planter with seating © South East Rivers Trust

Championing SuDS

While SuDS provide real benefits for the local area, they often go unnoticed or unrecognised.

To champion these innovative and nature-friendly solutions we:

  • Attended local fairs with a demonstration garden planter and child-friendly SuDS kits.
  • Worked with pupils to create a SuDS animation.
  • Installed interpretation near SuDS features.
  • Delivered community workshops to support residents in making their own planters.

Watch the SuDS animation here

Pupils engaged with SuDS © South East Rivers Trust

Want to find out more?

We have developed a number of reports that share our expertise and the learning we gained through the SuDS in School’s Project.

SuDS Education and Engagement Report

SuDS Planter Design Report

SuDS Planter Installation Guide

SuDS Monitoring Report

SuDS Rain Garden Report

For more inspiration on designing SuDS, visit this website.

Bee-friendly rain garden planter © South East Rivers Trust

SuDS at home

Large-scale changes in domestic garden cover can also dramatically increase the pressure on the drainage network.  This means we all have a role to play.

Here are some ideas for making your garden more rainwater friendly.

Install a water butt

Green your garden

Make a rain garden

Build a SuDS planter


A diagram of a rain garden © South East Rivers Trust

Thanks to our supporters

Thames Water
SES Water
London Borough of Sutton
Thames Rivers Trust
Environment Agency logo