Project overview
The River Wandle is one of just 200 chalk streams in the world—globally rare habitats known for their clear, fast-flowing waters and rich biodiversity.
At Culvers Avenue, however, this stretch of river is under pressure. Historic modification, pollution and surrounding development have reduced water quality and limited the habitats wildlife depends on.
The South East Rivers Trust is working with local communities to restore a 350m stretch of the Wandle’s western channel. By reintroducing natural processes and improving habitat diversity, this project will support healthier wildlife populations while creating a better river for people to enjoy.
The River Wandle at Culvers Avenue © South East Rivers Trust
The challenge
This section of the river has become over-wide, causing water to slow down. This allows sediment to build up and smother the gravel riverbed—an essential habitat for fish spawning and aquatic insects.
Dense tree cover also blocks light from reaching the river and its banks, limiting the growth of plants that provide food and shelter for wildlife.
At the same time, the channel has become uniform in shape, lacking the natural sequence of shallow riffles and deeper pools that a healthy river needs.
Local residents have already taken positive action by introducing woody material to improve flow in places. This project builds on that momentum to deliver a more comprehensive, long-term restoration.
Overhanging trees along the River Wandle © South East Rivers Trust
What we’re doing
We are restoring natural river processes to improve water flow, habitat diversity and ecological health.
Riffle and pool creation
We will reshape the riverbed to create a natural pattern of shallow riffles and deeper pools. These features provide vital spawning areas for fish and support a wide range of aquatic species.
Tree management
Selective tree works will allow more light to reach the river and its banks. This encourages the growth of native vegetation, which provides food, shelter and stability for wildlife.
In-channel wood structures
Using wood sourced from the site, we will install flow deflectors within the channel. These features help increase flow velocity, keeping gravels clean and improving conditions for fish and invertebrates.
Flood risk assurance
Independent modelling by Thomas Mackay Ltd has confirmed that these works will not increase flood risk to nearby properties.
Introducing woody materials to slow down the flow of the river © South East Rivers Trust
Project impact
By restoring natural river processes, this project will:
- Improve water flow and reduce sediment build-up
- Create healthier habitats for fish, invertebrates and plants
- Support biodiversity in one of the world’s rarest river types
- Build resilience to future environmental pressures
- Enhance a local green space for the community
Working with the community
Local people are central to this project. We’re creating opportunities for residents, volunteers and partners to get involved—from public consultations to hands-on restoration days.
This collaborative approach ensures the river reflects the needs of both wildlife and the community, while building long-term stewardship of this important local environment.
Get involved
From volunteering and citizen science to community events, discover how you can help improve rivers like the Wandle and make a difference for nature and people.
