Wetlands aren't just great for wildlife and people to enjoy, they also serve an essential purpose as part of nature’s flood defence system.
Climate change is likely to mean more frequent and intense flooding for the UK. WWT has been working to develop a more sustainable and efficient way to manage flooding using our wetlands.
Flooding has always been a threat to our island life but over recent years we have seen more devastating effects from it than ever before. Traditionally hard flood defences been used to manage flooding but it is now widely recognised that these defences alone are not enough.
What is natural flood management?
In recent years, there has been increased attention given to softer approaches that offer more sustainable ways of managing flood risk. Natural flood management (NFM) is an approach that uses opportunities in the landscape to hold back and slow down the flow of water before it reaches properties and businesses.
It encompasses low-cost techniques such as:
Woody debris dams
Off-line water storage
Improved soil management
Tree and hedge planting
These flood management techniques work with and restore natural processes to reduce flood risk at a catchment scale. It can also complement and extend the lifetime of traditional defences and provides benefits to wildlife and people through the creation of healthy, nature-rich wetlands and water-friendly land management practices.
What we are doing
By developing several examples of NFM across the UK WWT are working hard to showcase the effectiveness of such an approach to flood defence and bring relief to communities threatened by the devastating effects of flooding.
The short, steep-sided catchments of the Cotswold escarpment are particularly prone to flash-flooding, and parts of Gloucestershire have suffered extensively in recent years, particularly in 2007. As a result, NFM has being adopted as a means of managing flood risk in a number of catchments. WWT is supporting this work by undertaking a programme of research to provide some much-needed evidence on the effectiveness of NFM and the multiple additional benefits this approach provides.
The Twyver NFM project, managed by Gloucester City Council and delivered by Gloucestershire Wildlife Trust, aims to reduce flows and increase attenuation and reduce sedimentation in the upper Twyver catchment, whilst creating habitat and providing amenity benefit. NFM measures will range from land and soil management to in-stream structures and off-line storage.
Through the Two Valleys – Slow the Flow project, residents living in the catchments of the Monksilver and Doniford streams in Northwest Somerset will benefit from new measures to protect them from flooding, using natural methods such as planting hedgerows and creating wetlands.
Since 2014, Stroud District Council have been working with local communities, landowners, farmers and partner organisations to install a range of NFM measures in the River Frome catchment. Over 300 measures, of which 190 are woody debris structures have been installed along 19km of watercourse, affecting water flows in approximately 21 per cent of the catchment.
Monitoring work is being developed in partnership with Stroud District Council, Gloucester Wildlife Trust and the University of Gloucestershire and the Environment Agency.