Source: Angling Trust
The Angling Trust is following up the publication of a major report on dredging by the Chartered Institution for Water and Environmental Management this week, reported HERE on FM, by calling on the government to focus on land management, rather than dredging rivers and building yet more flood defences.
Research clearly shows that changes in land use reduce run-off and increase infiltration, which reduces the height of flood peaks, and reduces the amount of sediment washing into rivers.
One recent study by the highly respected Centre for Ecology and Hydrology demonstrates that that planting forests can increase the rate that water soaks into the ground by more than 1000%. Another study by Newcastle University found that construction of low cost, artificial ponds could capture so much water in a catchment in the North East that the flood peak in a town downstream could be reduced by 30%.
These techniques are much more effective, cheaper and more sustainable than dredging and flood defences. What’s more, they allow water to fill up aquifers which keep rivers flowing during the summer months and have numerous environmental benefits because they reduce the quantity of silt, pesticides, slurry, fertilisers and urban pollution being washed into rivers and at the same time create valuable wildlife habitats.
Calls for dredging have come from the farming lobby, but a 2009 Defra report in support of its Soil Strategy for England found that agriculture is responsible for 75% of the sediment in rivers. A Countryside Council for Wales report in 2009 found that 14 tonnes of sediment a year per hectare were being washed off an agricultural catchment in Wales, leading to a quadrupling in the rate that sediment is being deposited in Llangorse lake since the 1970s.
An Environment Agency report in 2010 found that large scale changes in agricultural land management, especially in the uplands have the potential to decrease river flows in the River Calder by 25%. Tackling run-off from farmland would therefore not only reduce flooding, but it would reduce the amount of silt getting into rivers in the first place.
As long ago as 2006, several environmental and angling organisations drew up a Blueprint for Water setting out a wide range of actions that government should take to take an integrated approach to sustainable water management. In spite of repeated reminders over the past 8 years, which have included severe droughts and highly damaging floods, little action has been taken. We hope that the current floods will finally get the government to implement the Blueprint which included measures to reduce the speed and quantity of water running off agricultural land and urban areas.
Mark Lloyd, Chief Executive of the Angling Trust said:
“For too many years farmers have been encouraged to focus on production at the expense of their own soils. Crops like potatoes and maize can have disastrous consequences when grown in the wrong place, because they lead to rapid run-off of water and soil.
In towns, far too many developments are being built without sustainable urban drainage systems in them. As a result, people’s homes and businesses are being flooded and our rivers are being polluted with torrents of sediment and other pollutants.
Widespread dredging of rivers would have made little or no difference to the impact of this year’s floods, but integrated catchment management might well have saved thousands of people from a heap of misery. We need to deal with the causes of flooding, rather than the effects.”
