The Wildlife Trusts are calling on UK Governments to invest in natural solutions to control flooding
Storms and flooding have caused significant damage across the UK, and climate change is likely to increase the frequency of such extreme weather in the future, costing Governments and taxpayers millions and devastating communities and businesses.
Now is the time for UK Governments to prioritise investment in wilder landscapes to provide the natural solutions so badly needed to help prevent flooding in future
The Wildlife Trusts believe that now is the time for UK Governments to prioritise investment in wilder landscapes which could provide the natural solutions so badly needed to help prevent flooding in future. Habitats such as upland bogs and moors, woodlands, wetlands and species-rich grasslands act as giant sponges, absorbing and holding water and slowing down water run-off into rivers.
There are already some excellent examples of how restored landscapes have made space for water, for example, in upland areas where old drainage ditches have been blocked and overgrazing reduced. This allows vegetation like sphagnum mosses and heather to regenerate, helping to hold water in the hills for longer and reducing peak flows downstream during high rainfall events. Across the UK Wildlife Trusts are working on large-scale habitat restoration schemes which slow down water and reconnect rivers with their floodplains, making space for water. We need these kind of approaches to be significantly extended across the country. This can only happen if investment in flood defence is rebalanced towards these more sustainable solutions.
The source of the problem?
Heavy rain will always occur, but the effects in today's built-up areas are directly related to land-use upstream and our inadequate urban drainage systems. Many of our major river catchments rise in the blanket bog areas of the uplands which, when in good condition, soak up the water and release it slowly, reducing the height, effects and ultimately the cost of flooding to society. But many of these upland blanket bogs are badly damaged and unable to store water.
Across many river catchments soil compaction, caused by intensive grazing and modern farming techniques, mean that the ground is less able to hold water, causing water and soils to run off into rivers and streams. Loss of habitats such as wetlands, peatlands, floodplain meadows, hedgerows and woodlands has also made the countryside less absorbent.
The need for costly and damaging desilting works could be much reduced through better land and soil management
Soil runs off the land into ditches and rivers, and into the sea, where it is washed back up into rivers by the tide. This increases levels of silt in channels and leads to calls for dredging of channels to try and increase their capacity for holding water. The need for costly and damaging desilting works could be much reduced through better land and soil management, and dredging will not prevent flooding of land and communities following very high and prolonged rainfall. Such practices can also shift the flooding problems further downstream.
In January 2014 the Government responded to calls for a “Big Dredge” of rivers on parts of the Somerset Levels. The Wildlife Trusts believe that sensitive desilting at the right scale and in the right places can make a contribution and help keep water moving on the Levels, but it is only one small part of the solution. Extensive dredging also runs the risk of damaging the Level’s wildlife-rich wetlands, which bring visitors and income to local economies. Please see our rural areas flooding page for our proposals for building a more flood resilient future on the Levels.
Inappropriate development, such as that proposed by the Circuit of Wales' motorsport complex in 830 acres of Blaenau Gwent, change the hydrology of large areas, removing peat, culverting rivers and preventing the land from storing water - creating a real danger of further flooding downstream.
Much of the water that causes flooding runs off the hard surfaces of our roads, and areas like car parks, rather than being absorbed by the earth. Drainage systems cannot cope with the volumes of surface run-off and the water quickly inundates homes and businesses. These impacts are all exacerbated where homes and businesses have been built in the natural floodplains of rivers and streams.
Engineered and “hard” flood defences are constructed in an attempt to protect vulnerable communities from flooding, and in some areas they are the only solution. But when a river is cut off from its floodplain by man-made flood defences, its natural spreading room is not available and it ceases to function naturally. Many of our rivers are now disconnected from the land and we have lost large areas of marshlands, reedbeds and wetlands that would help store water and filter out pollutants. Instead, the water keeps going in its artificial channel, straight through any built-up areas. If the rain keeps falling back in the uplands, the river will burst its banks or overtop the flood wall. Building and maintaining of flood defences is expensive, running to hundreds of millions of pounds and it can only do so much.
What we need to do
A renewed impetus is needed to put nature back into the landscape, changing the way we manage the land so that it works to protect communities from flooding. We must act now to protect and extend natural habitats - the kind of woodlands, wet meadows, pastures and wetlands that soak up and store rainwater. We can also mimic these natural processes in urban areas, weaving water-holding habitats into the urban fabric - installing more green roofs on our houses, more permeable surfaces in our towns and cities and more sustainable drainage systems to capture excess water. And along the coast natural habitats can be created that reduce the force of tidal surges elsewhere.
Working with nature will reduce our vulnerability to the impacts of flooding and climate change and increase resilience in the future. It is cost effective and delivers many other benefits: creating niches for wildlife, increasing people's wellbeing and benefiting tourism and local economies.
The Wildlife Trusts believe that the time has now come for a radical re-think on how we manage our rivers and the land that they drain, in both rural and urban areas. Shifting our attitudes and approach to these issues will require leadership at national and local level.
We challenge the Governments of the UK to answer our call for this step change to be made.
Read The Wildlife Trusts' flood action plan from the What needs to happen box.