What farmers can do to protect their local community from flooding


The topography of Devon and Cornwall means that most farms are built uphill, so floods are less of an issue for many farmers in this part of the world. While we do have a growing number of Members in Somerset, where many rural properties are built on flood plains, Cornish Mutual is generally in the position of insuring the farm at the top of the hill.

Whether or not farmers are at risk of their own property being flooded, they need to consider the impact of their farm on the wider community. At Cornish Mutual we have dealt with claims against farmers when a property near their fields gets washed away. Farms impact on a much wider area and neighbouring properties will be affected by how much water the farm land can hold.

The South West experiences more rain than much of the UK – particularly on the higher grounds of Bodmin Moor, Dartmoor and Exmoor. From mid-October to the end of March much of the region’s land is at full moisture capacity. This is also the time when land is most likely to be compacted, which increases risk of runoff and flooding.

In recent years, a number of studies have shown how land management can increase the risk of flooding. There have also been a number of ideas put forward on how to look after the land differently to reduce that risk, including high profile and controversial proposals to bring back beavers to Devon and Cornwall, to naturally slow down the flow of water.

There is a growing body of evidence that the answer lies – in part at least – in how we look after our soils. Richard Smith has produced a detailed report on soils and natural flood management in Devon and Cornwall for the Environment Agency and partnership organisations. The report highlights the key times when soil compaction can occur on farms. This includes autumn and winter harvesting of crops, such as vegetables, maize and potatoes, and late drilling of crops during the autumn – particularly when the last machinery press compresses the soil. It also highlights the impact of winter slurry and manure spreading, overwintering of livestock and winter hedge cutting and winter ditch clearance.

So, what should farmers do to ensure their soil remains well drained and permeable? The direction of ploughing, whether or not drainage ditches are clear, and adding or removing hedges can all have an impact on our land. A bit of forethought can prevent a lot of harm from flooding.

The report also has the following advice:

  • Where possible, carry out slurry spreading when the soil is dry.
  • Fields used to grow vegetables should ideally be relatively level and have a low risk of runoff.
  • Good soil structure can be achieved and maintained by drilling in suitable soil conditions in the early autumn to ensure good crop cover before the onset of winter.
  • Fields used for out-wintering of stock should be relatively level and access points should be located to avoid channeling runoff.
  • Soils should be loosened after harvest to remove inevitable compaction and reduce the risk of enhanced runoff during winter.
  • Temporary filter fences can be used to slow down runoff and to trap sediment when growing high risk crops.
  • Temporary ditches and single plough furrows can be created to divert runoff from headlands to soakaway areas.
  • Drainage ditches can be blocked with dams to slow down runoff provided water does not block drain outfalls.


By Cornish Mutual Technical Leader Paul Haddrell