The Soil Conservation Service (SCS) Runoff Curve Number method has been successfully applied to the Pickering Beck catchment at Pickering in North Yorkshire to assess the impact of land use change on flood flows. While limited-scale woodland creation (3% of the catchment) was predicted to have a small effect on the range of peak flows studied (<1% to 4% reduction), in line with previous model applications in the catchment, the conversion of the 25% cover of existing woodland to improved grassland produced a large increase in peak flow, up to 41% for a 1 in 100-year event. These numbers need to be treated with particular caution since the SCS method remains to be validated for UK conditions, however, they support growing evidence that woodland creation and management could have a significant role to play in flood risk management. The SCS method provides a potentially powerful tool for evaluating the impact of land-use change and management on flood runoff, as well as for identifying areas where such measures could be most effective.
curve number method, flooding, land-use change, natural flood management, rainfall-runoff modelling
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