Modelling soil dewatering and recharge for cost-effective and climate resilient infrastructure

About the Project

Supervisory Team: Tiina Roose and Siul Ruiz

Soil is one of the most complex and important self-assembling organo-mineral composites in the world. All human food supply, ecosystem and infrastructure services depend on soil. Movements of water into, within and out of soil are especially important.

In geotechnical infrastructure, it is essential to understand the processes involved in detail, both for controlling groundwater levels and pore pressures during construction, and for potentially managing soil water content to mitigate extreme cycles of seasonal wetting and drying caused by climate change.

There are particular issues that require a better understanding of soil water entry and exit processes, including:

• the depressurisation of relatively low permeability soils, particularly those comprising grains of mixed mineralogy and typical size. What is the effect of applying a vacuum at the soil / well boundary, in terms of additional depressurisation in the soil? How is this distributed within the soil? How would partial or zonal desaturation affect the behaviour?
• the recharge of soils and waste landfills, where clogging of the soil pores by impurities or the movement of fine particles can be an issue
• combining the above points, what is the feasibility of controlled water abstraction or injection to mitigate vegetation / climate induced seasonal changes in water content that lead to major shrink/ swell issues with clay embankments in particular. How would this be affected by zones of preferential flow and / or air entry?

In this project we will develop new mathematical models of soil wetting (water injection) and dewetting (water abstraction) that will enable:

• development of new understandings of what in particular influences air entry and water exit effects into and from fully saturated soils
• investigation of the microscale processes the influence soil wetting, and how these may be modified on the pore scale
• taking into account the role plants play in these processes
• assessment of the feasibility of engineered mitigation of the effects of climate induced water cycles on the wetting and dewetting of volume-sensitive soils

Entry Requirements

You must have a UK 2:1 honours degree, or its international equivalent, in numerate subject of engineering, physics, chemistry or mathematics.

Closing date: 30 September 2026. Applications will be considered in the order that they are received, the position will be considered filled when a suitable candidate has been identified.

Funding: This project is funded by a Wolfson Fellowship supporting studentships funded by the university.

For more information, please visit our postgraduate research funding pages.

How To Apply

Apply online: Search for a Postgraduate Programme of Study (soton.ac.uk)

You need to:

• choose programme type (Research), 2026/27, Faculty of Engineering and Physical Sciences
• select Full time or Part time
• search for programme PhD Engineering & the Environment (7175)
• add name of the supervisor in section 2 of the application

Applications should include:

• your CV (resumé)
• 2 academic references
• degree transcripts and certificates to date
• English language qualification (if applicable)

For further information please contact: feps-pgr-apply@soton.ac.uk