Hydromorphological evolution of a restored river; a case study in the Upper River Eden catchment

River restoration has undergone a shift in approach from structural interventions controlling unwanted erosion to river naturalisation and the “re-meandering” of channels back to an historic planform. This is driven by acknowledgement of rivers as dynamic systems that, through restoring erosional and depositional processes and floodplain connection, can restore channel features. Restoring processes is expected to increase the long-term success of a restoration project. Swindale Beck is an example of such a natural flood management approach, where new active meandering channel was constructed, replacing the original canalised channel. Data acquiring by a small unmanned aerial vehicle (sUAV) facilitated topographical and photogrammetric data (at the centimeter scale), used to characterise habitat, assess sediment and sediment flux within the restored reach. The results show rapid initial response; erosion and deposition at the site show rates in line with levels expected of an active meandering system. Hydraulic modelling and habitat availability (through Froude numbers) determined and compared biotope presence and diversity in the channel pre and post restoration. Results show an increase in the diversity of biotopes present within the restored reach, transitioning from a run dominated river system. Bed shear stress was investigated across the reach to determine levels of entrainment with the majority of the reach subject to bed shear stress above the critical boundary for entrainment, significantly enhancing the post-restoration channels geomorphology, habitat and variability