Curtailment of muddy floods in the Sompting catchment area

The conversion of agricultural land to grassland and other management changes resulted in a drastic reduction of muddy floods, soil erosion and runoff in the Sompting catchment area in the South Downs of the UK. 

Nature-based Intervention:

In 1992, around 100 hectares of agricultural land, mainly located on slopes vulnerable to runoff and erosion, were permanently set aside to revert back into grassland, funded through the EU’s Common Agricultural Policy and an Environmentally Sensitive Area scheme.

Overview of context and outcomes:

Prior to these changes, the area and town of Sompting experienced intense flooding and excessive soil erosion in the 1980s and early 1990s. As a result of the intervention, runoff and continuous down-valley flows were reduced and valley floor flows were prevented from linking up, reportedly reducing flooding. Much less frequent flooding events were observed after the intervention, even in particularly wet years, according to a peer-reviewed study of the area.