Through Water Resource Modelling, this project studied in depth all the underground reservoir which supplies drinking water to most of the population of Montpellier, to ensure sufficient water supplies and anticipate the impacts of a changing climate.
Title of Project: Impact of global changes on the supply of drinking water to the Montpellier Urban Community
City, Country: Montpellier, France
French partner submitting the project description: Geology and Mining Research Institute (BRGM)
Project Owner: Montpellier Urban Community
French Partners : UMR Hydrosciences, G-EAU, TETIS, Biotope, CERFACS
Financiers : Rhone Mediterranean Corsica Water Agency, Herault General Council, Montpellier Urban Community
Dates of project: 2011-2014
The Lez Spring supplies drinking water to the 340,000 residents of the Montpellier Urban Community in southern France. This very large reservoir of groundwater is subject to climate change, which should result in a decrease in the quantity of water even as the population is projected to grow over the coming years. It is therefore essential to anticipate the impacts of a changing climate and changes in water demand on water levels in the reservoir and flow rates in the Lez River.
Involving Hydrosciences UMR G-EAU, TETIS, Biotope company and CERFACS Toulouse, this project coordinated by BRGM for the Agglomeration of Montpellier studied in depth all the underground reservoir which supplies drinking water to most of the population of Montpellier.
It aims to better understand the structure and functioning of this important hydrogeological groundwater resources using field approaches and modeling, addressing a wide range of issues :
- understand the underground environment from a geological and hydrogeological perspective,
- assess the quantity, quality and vulnerability of water resource,
- characterize the impacts of climate change,
- better measure the risk of flooding.
- produce an inventory of the underground biodiversity of the aquifer.
Geological and hydrogeological model of the Lez area. © BRGM
The results of modeling make it possible to determine a sustainable level of water withdrawal for the future - incorporating seasonality into withdrawal strategies - and to propose alternative resource management strategies than those currently used; increasing withdrawals would make it possible to supply at least 390,000 inhabitants by 2030 without jeopardizing aquatic ecosystems.
The simulation of different types of scenarios also opens up discussions sufficiently early to enable changes to be made to regulatory aspects relating to withdrawal, such as declarations of public utility for the exploitation of resources.
Strengths of project
This comprehensive local study, ranging from the assessment stage to recommendations, addresses multi-use issues and highlights links between socio-economic and climatic factors.
The findings of this operational study provide water operators of the city of Montpellier with information on the future of water resources.
More information (link to project webpage)