Abstract
Muddy flooding is the result of sediment-laden runoff leaving arable fields and damaging property,
transport infrastructure, freshwater systems and giving rise to reservoir sedimentation. It is often,
but not always, associated with heavy rain. We describe a muddy flood event in west Wales in
January 2024 with runoff from a bare post-harvest maize field with poor soil structure. Milford
Association soils are not usually associated with erosion but heavy rainfall was implicated in this
case. Management of maize needs to include post-harvest crop cover or chisel ploughing to
remove surface compaction to ensure the soil is more resilient to heavy rainfall, and grass buffer
strips to attenuate runoff. Climate change is already increasing the frequency of high-intensity
storms and management of vulnerable crops such as maize will have to adapt to this change. In
high-risk locations it may be better not to grow vulnerable crops in the first place.