A study by an international team of scientists, led by the Universities of Birmingham and Southampton, has shown that strategic planting of trees on floodplains could reduce the height of flooding in towns downstream by up to 20 percent, according to research published in the journal Earth Surface Processes and Landforms.
Researchers studied a whole river catchment in the New Forest over an area of 100 square kilometres, upstream of the town of Brockenhurst. They wanted to understand how tree planting, river restoration and logjams might affect the ‘peak height’ of a flood in a downstream urban location.
The research was funded by the Environment Agency who is interested in the potential for river restoration techniques to be incorporated into wider flood risk management programs. Using a digital terrain model of the landscape and a hydrological model simulation the scientists found that planting trees on the floodplain and increasing the number of logjams, across 10-15 percent of the total river length could reduce the peak height of a potential flood in the town by 6 per cent once the trees had grown for 25 years.