Project Highlights:

  •  Managing Scotland’s rivers is hindered by a critical data gap associated with a lack of grain-size data at bar to catchment scales.
  • Novel Small Unmanned Aircraft Systems (sUAS, or drones) facilitate data collection at the ‘sweet spot’ of high resolution and wide spatial coverage.
  • The project will develop and apply an image-based ‘sediments toolkit’ to assist with understanding geomorphic response to hydrological events and promote effective river management with wide applicability.


Flood intensity is increasing in the UK and many rivers are becoming more mobile, particularly Scotland's flashy and sediment laden systems. Our understanding of how river systems respond to flood events comes principally from morphological measurements, and neglects the critical role played by the nature of the bed material in controlling the entrainment and mobility of sediment, channel conveyance during floods, and the ability to support ecologically and economically important fauna & flora.

The Scottish Environmental Protection Agency (SEPA; CASE partner) have identified the lack of grain-size data at bar to catchment scales as a critical data gap, limiting their ability to predict future patterns of channel erosion/deposition and to model flood risk. Obtaining such data is therefore a key priority, but its availability is limited – principally because it is expensive and time-consuming to collect.

Recent technological developments – particularly in small Unmanned Aircraft Systems (sUAS or “drones”) and structure-from-motion photogrammetry – provide the opportunity to obtain data in the ‘sweet spot’ of high resolution and wide spatial coverage. This project aims to exploit these developments to create and apply an image-based 'sediments toolkit' for the characterisation of river bed sediments at local to catchment scales to improve the management of river sediments and modelling of flood risk.

The project is driven by the need of SEPA for information to help them better manage Scotland's rivers. However, the toolkit will be applicable to river research and management problems in the rest of the UK, and beyond. An example benefit will be improvements in the implementation of the Water Framework Directive. This requires assessment of the hydromorphological and ecological quality of water bodies, for which sediment characterisation is essential. Rivers below ‘good’ status require restoration at the catchment scale, making data collection at this scale critical. Returning rivers to more sustainable, flood-resilient morphologies is a key restoration approach. This must be process-based, which requires understanding of sediment characteristics at local and at catchment scales. Mapping grain size across larger scales will therefore facilitate the design and monitoring of management schemes.

This work will build upon the expertise of Dr Graham in image analysis for sediment characterisation and Dr Wackrow in digital photogrammetry with sUAS-derived imagery. The supervisors at SEPA will bring detailed knowledge of the challenges associated with managing Scotland’s rivers, and the data required to meet these challenges.

Aerial image of Derry Burn, Cairngorm Mountains, collected with a small Unmanned Aircraft (image approx. 50 m across). The project will use similar images to map sediment size at local to catchment scales.


The project will build on published methods of grain-size measurement from images, and new image-analysis developments (such as structure-from-motion). Using the ability of sUAS to obtain data over a wide range of spatial scales and resolutions, we will identify the most appropriate datasets and methods for a wide range of applications and combine these into a software 'sediments toolkit' with associated documentation and guidance.

The toolkit will be tested on the River Dee, Aberdeenshire, where the 2015/16 floods caused significant damage and SEPA has an urgent need to integrate information on sediment properties into the management strategy. It will be used to identify

potential zones of sediment supply, erosion and deposition. Management strategies will be designed to reduce flood risk, mitigate threats to infrastructure and maintain hydromorphological integrity.

We also explore applications in other environments – such as gravelly beaches – where grain size is of fundamental importance for understanding adjustment to floods and storms.

Training and Skills

CENTA students are required to complete 45 days training throughout their PhD including a 10 day placement. In the first year, students will be trained as a single cohort on environmental science, research methods and core skills. Throughout the PhD, training will progress from core skills sets to master classes specific to CENTA research themes.

Civil Aviation Authority (CAA) approved training will be provided in the use of sUAS for commercial operations. Specialist training in sediment characterisation using digital image analysis, structure-from-motion photogrammetry and appropriate software packages will be provided by the supervisors. The project is likely to involve the use of a variety of programming languages and environments (including Matlab, Python, R and Ruby on Rails), and support will be provided to enable the student to acquire and develop the required programming skills.


Year 1: A significant part of this year will be spent reviewing existing literature, learning key skills and refining the project aims. Time will be spent on field data collection and on placement with SEPA.

Year 2: The majority of the toolkit development work is likely to be done in this year.

Year 3: This year will be spent applying the toolkit to the key problems identified in association with SEPA. This will be facilitated by a period on placement with SEPA. There will also be an opportunity to apply the toolkit in a beach environment via a placement with the Environment Agency.

Partners and collaboration (including CASE)

This project is a CASE partnership. The involvement of the Scottish Environmental Protection Agency (CASE partner) is central to this project. The student will spend two periods shadowing Drs Helen Reid and Roberto Martinez from the Hydromorphology Team in Stirling, gaining insights into the role and importance of hydromophology in managing Scotland’s rivers. They will be involved in designing and evaluating restoration projects and in catchment-scale planning initiatives. They will also have an opportunity to undertake placements at the Environment Agency under the supervision of Dr John Phillips.

Further Details

For further information, or to discuss the project, please contact Dr David Graham (D.J.Graham@lboro.ac.uk). For enquiries about the application process, please contact Susan Clarke, Department of Geography, Loughborough University (S.N.Clarke@lboro.ac.uk). Please quote CENTA when completing the application form: http://www.lboro.ac.uk/study/apply/research/.