LEESU, École nationale des ponts et chaussées, Institut polytechnique de Paris

Leesu (https://www.leesu.fr/) develops interdisciplinary research on water in the city. Its objective, in line with the challenge of making cities sustainable and resilient to global changes, is to gain a better understanding of water and contaminants flows and fate in urban environments, and to develop innovative concepts for water and soil management. The research is based on in situ and/or controlled laboratory observations, and their interpretation in order to produce quantitative and predictive models. Leesu coordinates since 1994 the OPUR observatory of urban hydrology, a long-term research project and a means for structuring scientific expertise in the Paris metropolitan area.

Homepage: https://ecoledesponts.fr/

Research Context:

Urban water systems face growing pressures from increasing population density, rapid urbanisation, and the impacts of climate change (Flörke et al., 2018). Expanding impervious surfaces, aging infrastructure, and increasingly unpredictable weather patterns make urban areas particularly vulnerable to water- related challenges, such as flooding, water quality degradation, and water scarcity. The current segmented management of surface and underground aquatic environments, drinking water, wastewater, and stormwater is insufficient to address the combined challenges of securing water supplies, enhancing resilience to extreme climatic events, and preserving aquatic ecosystems in the city of tomorrow. The complex interrelationships within urban water systems necessitate a more comprehensive approach, an integrated urban water management (Bach et al., 2014), to manage interactions between various urban water system components and achieve greater water circularity in cities.

Some of the proposed decentralised urban water infrastructures (e.g., at-source stormwater management (Tunqui Neira et al., 2023), decentralised wastewater and grey water reuse; and the mobilisation of alternative resources) have already undergone technical assessment. However, these evaluations are typically limited to project-scale analyses and segmented by specific issues. These solutions have yet to be evaluated on a city-wide scale. Their coherence, complementarity, potential competition, and integration with existing systems still require further analysis to assess their contribution to a new paradigm of urban water management.

Aim and objectives of the PhD thesis

This PhD thesis aims to assess the interactions and impacts of decentralised urban water infrastructures

at the city scale under global change, using an integrated urban water system modelling approach. Objective 1) Identify and characterise decentralised urban water infrastructures that address current challenges in urban water systems.

Objective 2) Develop scenarios for the deployment of decentralised urban water infrastructures in the Paris region.

Objective 3) Further develop WSIMOD (Water Systems Integrated Modelling, Dobson et al., 2023) to assess the interactions and impacts of deploying decentralised urban water infrastructures at the city scale.

Objective 4) Apply the model developed in Objective 3 to a case study in the Paris region to evaluate the interactions of the decentralised urban water infrastructures identified in Objective 1 under the deployment scenarios developed in Objective 2.

Capacity / Candidate Profile:

The ideal candidate should have a strong background in environmental or urban hydrology, water resources management, or related disciplines. Skills in numerical modelling, Geographic Information Systems (GIS), and programming (Python, R, or MATLAB) are highly desirable. Experience with integrated water management, or sustainability assessment will be an advantage. The candidate should also have strong analytical and communication skills, enabling them to interpret complex datasets and present results to both academic and non-academic audiences. Motivation to work in an interdisciplinary environment and interest in addressing global change challenges in urban water systems are essential.

Supervision:

The successful candidate will be supervised by Pr Ghassan Chebbo (Research Director, Director of LEESU; ghassan.chebbo@enpc.fr), Pr Maire-Christine Gromaire (Research Director, marie-christine.gromaire@enpc.fr), and Dr Yangzi Qiu (Researcher, yangzi.qiu@enpc.fr). The PhD will be conducted at the LEESU Laboratory (Laboratoire Eau, Environnement et Systèmes Urbains) at the École Nationale des Ponts et Chaussées, Institut Polytechnique de Paris.

Interested applicants are invited to send their CV and Personal Statement to ghassan.chebbo@enpc.fr; marie-christine.gromaire@enpc.fr; yangzi.qiu@enpc.fr.

Please use the following subject line in your email: “2026 PhD Apply – YourName” .