Flooding is a natural process but climatic changes and the way we manage our landscapes are causing it to become more frequent with increasing devastation to homes, communities and infrastructure. It is predicted that in the U.K. total rainfall will increase in winter with individual storm events becoming more intense. We need to adapt to better manage flood risk; what we have done in the past is unlikely to be sufficient in the future.
Many factors have contribute to increased flood risk in towns and villages. Across large areas soils are compacted and have lost their capacity to store water. Wetlands have been drained and smooth grass fields with few trees allow water to flow quickly into river channels. In many places rivers have been straightened and dredged to move water quickly downstream towards towns and villages. When this huge volume of water reaches a town and is squeezed through walled channels and under bridges it spills out onto its floodplain. Building and development on floodplains leaves the water nowhere to go and so it floods property. We need to slow the speed of water coming off the hills and store more water on natural floodplains.
‘Natural Flood Management’ is the alteration or restoration of landscapes to store water or ‘slow the flow’
of water reaching the river channel.
Natural flood Management techniques are cost-effective, sustainable and deliver lots of other benefits such as cleaning water, storing carbon and increasing wildlife.
See how we can manage our catchments to help reduce the risk of flooding:
So what do we actually do for ‘Natural flood Management’?
Restoring our natural habitats
We can also use natural materials to engineer structures within the landscape that store flood water and slow the flow.
For example, building bunds and ponds with extra capacity can allow water to be stored during flood events then drain away slowly. Leaky dams across water courses or pathways of runoff can slow the flow downstream.
The video below shows examples of these different techniques.
Research and Modelling
The Environment Agency have produced maps identifying the opportunities for a range of Natural Flood Management techniques.
These maps help identify which sub-catchments may be most suitable for NFM interventions and will help us plan and deliver measures to reduce flood risk to local communities.
Mapping was undertaken for the following options:
Detailed information about the current state of scientific understanding on Natural Flood Management can be found here.