Apply for this PhD here https://applyto.newcastle.ac.uk/ using application studentship code FLOOD241. Please contact Caspar Hewett (caspar.hewett@newcastle.ac.uk) if you have any questions about the application process.
Management interventions aiming to modify the catchment runoff response to rainfall inputs are pervasive across the UK, with the majority seeking to either: a) modify exchange between atmospheric and surface water stores; b) modify the runoff processes by disconnecting surface flow pathways; c) reconnecting rivers with floodplains to enhance temporary storage; or d) slowing the flow once water has entered channel networks (e.g. leaky dams). However, relatively little attention has been given to the relative contribution of subsurface flow pathways to the flood response. In some instances, these contributions can be both rapid and significant in response to rainfall inputs (e.g. Deasy et al., 2009). Many rural areas are drained by a dense network of drainage pipes that were installed (typically post WWII) to enhance drainage, and improve agricultural productivity. Disconnection of these pathways may have a significant effect on runoff response in catchments where infiltration-excess overland flow is rare. By understanding the significance of these networks’ contribution, and monitoring of targeted disconnections, this project will assess the potential for this type of intervention to contribute to the suite of measures that are currently available to land managers within countryside stewardship.
Monitoring subsurface movement of water is a challenging task, which is why we know so little about its dynamic contribution to catchment response. This project will adopt a range of remote sensing techniques to map subsurface drainage networks. Specifically, we will use multispectral and thermal cameras, and ground penetrating radar all mounted from uncrewed aerial systems (UASs). This will enable high resolution mapping of networks to be identified (Allred et al., 2004; 2020). We will identify the outflows of these pipes and monitor the water flux discharging into the adjacent Beck to determine their relative contribution to the flow discharge. Complementing the subsurface monitoring, we will identify the occurrence and magnitude of overland (sheet) flow contributions through application of image velocimetry techniques on video sequences acquired from fixed cameras and UASs. Together, these techniques will provide insight into the routing of flows to headwater streams, and we will identify their relative contributions and potential for modifications to alter rainfall-runoff dynamics.
Allred, BJ., Fausey, NR., Peters, L Jr., Chen, C., Daniels, JJ., Youn, H. (2004) Detection of buried agricultural drainage pipe with geophysical methods. Applied Engineering in Agriculture. 20(3): 307-318.
Allred, BJ., Martinez, L., Fessehazion, M.K., Rouse, G., Williamson, T.N., Wishart, D., Koganti, T., Freeland, R., Eash, N., Batschelet, A. and Featheringill, R., 2020. Overall results and key findings on the use of UAV visible-color, multispectral, and thermal infrared imagery to map agricultural drainage pipes. Agricultural Water Management, 232, p.106036.
Deasy, C., Brazier, RE., Heathwaite, AL., Hodgkinson, R. (2009), Pathways of runoff and sediment transfer in small agricultural catchments. Hydrol. Process., 23: 1349-1358. https://doi.org/10.1002/hyp.7257
