In recent years, people have been in favour of a more integrated approach to flood risk management across the catchment, with a call to move away from focusing solely on large scale structural flood defences in urban areas. This integrated approach aims to incorporate land management, development and resilience across a catchment from the tops of the hills down to the coast.
Starting at the top of the catchment, in the uplands where rivers begin to take shape from small streams, natural flood management is a hot topic. Whether it’s called ‘Slow the Flow’, upland management or natural flood management, the principle is the same; to use and manage the landscape in ways which slow the flow of water through the upland catchment, reducing peaks in river levels downstream.
Natural flood management is seen as a long term solution, with the majority of benefits realised in 10-20 years in most cases. Therefore, it is just one part of the jigsaw of a catchment management plan, and as we move down the catchment other aspects of integrated flood management fit into place. Agricultural land in the upper to mid section of the catchment can be valuable, therefore working with land owners through incentive schemes, such as the countryside stewardship scheme, can prove to be mutually beneficial in undertaking flood risk management activities, either through contour cultivation to reduce and slow down surface run off from fields or allowing areas of land in the flood plain to flood.
As we move down the catchment, it is here where the urban landscape and hard surfaces dominate and less water can be naturally absorbed by the land. Rainfall runs off these surfaces much more quickly resulting in drainage and rivers becoming overwhelmed. Therefore, sustainable urban drainage systems (SuDS) have become a major talking point, particularly in new developments. SuDS offer a natural approach to managing drainage systems, aiming to reduce peak flows and excess surface water in urban areas using techniques such as green roofs, permeable paving and swales. Therefore while larger more traditional flood defence schemes, including flood walls, still have their place in integrated flood management plan. Where appropriate we should encourage the incorporation of SuDS, natural flood management and other approaches into our flood management strategies, as we cannot simply continue to try and build our way out of the problem.
The final piece of the ‘jigsaw’ is resilience, as although physical flood defence projects whether natural or traditional are important in reducing flood risk. Communities must be aware that we will never be able to stop all flooding and therefore people must become as flood resilient and prepared as possible. This can be as simple as ensuring you are signed up to receive flood warnings, having a household flood plan in place or installing property level protection, using resilience measures such as a sump and pump system to reduce damage and speed up recovery. Communities working together to develop flood action groups and community schemes can also be a great way to improve community resilience.
Put simply, the idea is to slow the flow above the community, improving the ability of rivers and floodplains to manage floodwater and allowing communities downstream more time to prepare. Where water flows through the community, we need to ensure the flow is undisturbed and that water is kept in channel where possible. Through preventing blockages at pinch points, such as bridges, by dredging where appropriate, and controlling flow paths of surface water through communities to allow water back into the river channel. With multiple flood risk management techniques working together to reduce flood risk across the catchment, a collaborative approach produces benefits for all the parties that are involved.