The Climate Resilient Otter Catchment (CROC)

Reducing flood risk and improving catchment resilience

The Climate Resilient Otter Catchment (CROC)

Reducing flood risk and improving catchment resilience

Project title: The Climate Resilient Otter Catchment (CROC)

Funded by: Environment Agency

Location: River Otter Catchment, East Devon

Dates: September 2024 – August 2027

Project partners: Environment Agency (Exeter Office), University of Exeter and Clinton Devon Estates

University of Plymouth staff: Dr Paul Lunt (PI), Dr Rupert Goddard, Professor Will Blake

The Climate Resilient Otter Catchment (CROC) is an exciting new partnership project funded by the Environment Agency as part of its £25 million Natural Flood Management applied research programme. The research project aims to improve understanding of how different Natural Flood Management (NFM) measures reduce flood risk and improve catchment resilience.

Working in the River Otter catchment in East Devon, researchers are investigating how soil properties, land management, and landscape conditions influence water infiltration, runoff generation, and sediment transport. The findings will help identify the most effective NFM interventions and provide evidence to support future investment in nature-based approaches to flood management.

The project builds on the University of Plymouth's successful collaborations with the Environment Agency and Devon County Council through the Devon Resilience Innovation Project (DRIP), extending previous research into practical solutions for climate resilience.

The project will address five key questions:

How effective are soil-based Natural Flood Management measures, including land cover, soil type and soil condition, at reducing runoff and flood risk at both plot and catchment scales?
How long can the benefits of improved soil management be sustained under future climate change scenarios, based on soil infiltration performance and changing rainfall patterns?
What proportion of sediment in the catchment originates from riverbank erosion compared with agricultural runoff, using geochemical fingerprinting and X-ray fluorescence analysis?
How does the flood-management performance of protected heathland soils compare with that of neighbouring agricultural land within the catchment?
How can measurements of soil hydraulic performance be scaled from field plots to catchment-scale flood modelling?

Climate change is increasing the frequency and intensity of extreme rainfall events across the UK. In South West England, annual rainfall has increased by approximately 30% over the past century, while future storm intensities could reach up to 74 mm per hour under high greenhouse gas emission scenarios by the end of the 21st century. Understanding how healthy soils and well-managed landscapes can reduce flood risk is therefore critical for building resilient communities and catchments.

Dr Paul Lunt
Associate Professor in Environmental Science

The lower River Otter valley has experienced 24 flood events since 2008, many of which are linked to sediment-laden runoff from cultivated land. These events have caused damage to homes, transport infrastructure, farmland and drainage systems, highlighting the increasing vulnerability of rural catchments to extreme weather events.

As climate change drives more intense rainfall, there is an urgent need to understand how natural processes and land management can help reduce flood risk while delivering wider environmental benefits.

The CROC project will investigate the soil and hydrological processes responsible for surface runoff and flooding. By examining how soil condition, land use and management practices influence water movement through the landscape, the research will provide evidence for sustainable land management approaches that enhance natural flood resilience.

The results will support decision-makers, landowners and environmental managers in implementing cost-effective Natural Flood Management solutions that reduce flood risk while improving soil health and ecosystem resilience.

Smith and Boardman 2025