Natural Flood Management
Historically flood management typically involved a combination of dredging and straightening watercourses, alongside hard–engineered defence structures to protect properties from flood water and flooding events. Flooding events are now becoming more frequent and severe, and the cost of constructing and maintaining this traditional flood management approach is significant. Traditional approaches can also be carbon intensive and can negatively impact river processes and biodiversity.
We are now seeing a move to nature-based solutions to manage flooding; slowing the flow of water in headwaters through small scale interventions and allowing floodplains to function naturally. The Working with Natural Processes (WWNP) approach provides multiple benefits – including increased biodiversity, water quality and water resources management – helping protect communities and assets from the risks associated with flooding in an holistic and sustainable way.
Expected Increase in Flooding
In all, around 5.2 million properties in England, or one in six properties, are at risk of flooding and it is estimated that annual flood damage costs are in the region of £1.1 billion. The cost of building and maintaining flood defence assets is significant and can often have negative environmental outcomes. With the frequency and magnitude of flooding expected to increase because of climate change, the pressures on flood defence budgets will continue to grow.
Natural Flood Management (NFM) can take many forms and has been happening under different guises for several years. Many methods have been trialled and studied, and FiveRivers is able to apply this knowledge and experience to your project. Guided by CIRIA best practice (The natural flood management manual (C802F)) our experts can deliver effective catchment modelling and studies to implement and deliver effective NFM interventions. Depending on the project, we can either design and install interventions or promote ownership through the involvement of local landowners and interest groups.
Interventions include installation of leaky wood structures, floodplain restoration, offline storage creation, cross-slope / catchment and riparian woodland creation, soil and land management and the restoration of degraded headwater peatbogs and wetlands. Each catchment requires a bespoke approach, and that’s where FiveRivers key skills can be utilised.