Longevity of NBS: Analysing Longer-Term River & Floodplain Restoration Case Studies in the UK - PhD via FindAPhD

University of Southampton

Southampton, UK 🇬🇧

About the Project

Landscape change and climate change over the Anthropocene have resulted in increased risk to river and floodplain ecosystems and to catchment stakeholders through increased flood and drought impacts Conventional methods of engineering are unsustainable as longer-term solutions in most instances; thus novel Natural based solutions (NBS) are promoted as potential alternatives. Many NBS methods are available that rely on natural processes to improve sponge functioning in catchments. These methods include restoration of wetlands and reconnection of floodplains to provide more room for streams and river flood volumes. However, the effectiveness of many of these implemented measures across different scales (reach to catchment) is not properly monitored and evaluated; as a result, it is difficult to determine whether they have improved sponge functioning over time, or how sustainable these approaches have been in terms of needing further intervention. This PhD project will specifically address the research questions; 1) what is the evidence for the effectiveness of river and floodplain restoration of sponge measures to the overall reduction and delay in flood peaks and volumes during wet seasons as well as the improvement of base flows and ground water levels during dry seasons? and; 2) do river floodplain sponge measures contribute wider ecosystem benefits (e.g. organic matter and sediment retention, biodiversity gains). The research will contribute to a wider EU funded project SPONGESCAPES affording the candidates and opportunity to interact with a broader international team of scientists.

Long term monitoring of Nature based river and floodplain solutions are rare. This PhD project is novel in having access to up to 40 years of pre and post restoration data across different aspects of the river and floodplain ecosystems at the three sites (New Forest, Cole and Evenlode catchments). The methodology will involve collaboration with the wider SpongeScapes team to define best practice approaches. Case study methods will include collating and analysis of existing data, including data quality control and cleaning, statistical analysis of river discharge, rainfall and evaporation time series, suspended sediment and large wood timeseries, and potentially repeat ecological surveys (invertebrates and macrophytes). Repeat field-based data capture will form part of the methods to update datasets (potentially, repeat topographic survey and flow monitoring, large wood loading, suspended sediments, ecological data) and modelling of data – e.g. hydraulic performance of restored reaches). Metrics to define NBS/NFM effectiveness will be developed and evaluated for the three case studies. 

Training in data capture and analysis will be available alongside field data capture and laboratory analysis where appropriate. The candidate will benefit from world class field and data analysis facilities at the University of Southampton UK and CEH Wallingford. The candidate will join an ECR/PhD group within the wider EU SpongeScapes Project, and will have the benefits of interacting with the wider project team of international scientists. Technical support for field an lab analysis I available through the project for the Evenlode catchments. All Postgraduates will be enrolled in the Graduate training program which involves skills development in scientific writing, project management etc.

Funding Notes

This PhD is co-funded by EU Horizon SpongeScapes and the School of Geography and Environmental Science, University of Southampton.
The funding is for 3.5 years and comprises a stipend at UKRI rate and home tuition fees. An RTSG of £1000 is also included.


Sear, D.A., Millington, C., Kitts, D.R. & Jeffries, R. Logjam controls on channel:floodplain interactions in wooded catchments and their role in the formation of multi-channel patterns, Geomorphology, 2010,116, 3-4, 305-319.
Dixon, S. J., Sear, D. A., Odoni, N. A., Sykes, T., and Lane, S. N. The effects of river restoration on catchment scale flood risk and flood hydrology. Earth Surf. Process. Landforms, 2016, 41: 997–1008. doi: 10.1002/esp.3919.
Robotham J, Old G, Rameshwaran P, Sear D, Gasca-Tucker D, Bishop J, Old J, McKnight D Sediment and nutrient retention in ponds on an agricultural stream: evaluating effectiveness for diffuse pollution mitigation. Water; 2021, 13(12):1640.





IHE Delft Institute for Water Education - MSc in Water and Sustainable Development